Hydrological and hydrogeological effects of an open repository in Forsmark. Final MIKE SHE flow modelling results for the Environmental Impact Assessment

Energy Technology Data Exchange (ETDEWEB)

Maartensson, Erik; Gustafsson, Lars-Goeran (DHI Sverige AB (Sweden))

2010-07-15

This report presents methodology and modelling results concerning a deep-rock repository for spent nuclear fuel in Forsmark. Specifically, the modelling tools MIKE SHE, MIKE 11 and MOUSE are used to quantify the groundwater inflow to the repository and associated hydrological and hydrogeological effects during the construction and operation phases. The modelling results presented in the report provide input to the Environmental Impact Assessment (EIA) that will be part of a permit application according to the Environmental Code. Based on an existing MIKE SHE model for Forsmark, the first step of the modelling process was to implement an updated hydrogeological model of the bedrock and to increase the vertical and horizontal extents of the model domain. Other model updates involve the vegetation classification, and implementation of SFR (final repository for short-lived radioactive waste) and the subsurface drainage system at the nearby nuclear power plant. The updated model was calibrated using measured data on groundwater levels in the Quaternary deposits and the bedrock, water levels in lakes, and stream discharges. The calibrated model was then used for simulation of undisturbed conditions (i.e. without the repository) as a reference for modelling results obtained for disturbed conditions (with the repository). The modelling results for undisturbed conditions that are presented in the report closely resemble those of the final MIKE SHE site descriptive modelling (SDM-Site Forsmark). The repository layout was implemented as pipe links (segments) in the modelling tool MOUSE, and the implemented layout was used for the modelling of disturbed conditions. The study uses an updated and verified MIKE SHE-MOUSE coupling routine that is specifically adapted for calculation of groundwater inflow to grouted rock tunnels. The vertical shafts of the repository are implemented in the form of MIKE SHE grid cells with atmospheric pressure. Modelling results for disturbed

Forsmark site investigation. Interpretation of topographic lineaments 2002

International Nuclear Information System (INIS)

Isaksson, Hans

2003-04-01

SKB performs site investigations for localization of a deep repository for high level radioactive waste. The site investigations are performed in two municipalities; Oesthammar and Oskarshamn. The Forsmark investigation area is situated in Oesthammar, close to the Forsmark nuclear power plant. The purpose of interpretation of lineaments from topographic data is to identify linear features (lineaments), which may correspond to deformation zones in the bedrock. The data will be combined with interpretations of lineaments from airborne geophysical data in order to produce an integrated lineament interpretation for the Forsmark area. This integrated interpretation will be combined with geological data in order to establish a bedrock geological map of the Forsmark area. The area for the lineament interpretation is the same as that selected for the bedrock mapping activities during 2002, i.e. the land area around Forsmark

The influence of bedrock hydrogeology on catchment-scale nitrate fate and transport in fractured aquifers

Energy Technology Data Exchange (ETDEWEB)

Orr, Alison [Arup, 50 Ringsend Road, Dublin 4 (Ireland); School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom); Nitsche, Janka [RPS, West Pier Business Campus, Dun Laoghaire, Co. Dublin (Ireland); School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom); Archbold, Marie [School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom); Environmental Protection Agency, Richview, Clonskeagh Road, Dublin 14 (Ireland); Deakin, Jenny [Environmental Protection Agency, Richview, Clonskeagh Road, Dublin 14 (Ireland); Department of Civil, Structural and Environmental Engineering, Trinity College Dublin (Ireland); Ofterdinger, Ulrich; Flynn, Raymond [School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom)

2016-11-01

Characterising catchment scale biogeochemical processes controlling nitrate fate in groundwater constitutes a fundamental consideration when applying programmes of measures to reduce risks posed by diffuse agricultural pollutants to water quality. Combining hydrochemical analyses with nitrate isotopic data and physical hydrogeological measurements permitted characterisation of biogeochemical processes influencing nitrogen fate and transport in the groundwater in two fractured bedrock aquifers with contrasting hydrogeology but comparable nutrient loads. Hydrochemical and isotopic analyses of groundwater samples collected from moderately fractured, diffusely karstified limestone indicated nitrification controlled dissolved nitrogen fate and delivery to aquatic receptors. By contrast nitrate concentrations in groundwater were considerably lower in a low transmissivity highly lithified sandstone and pyrite-bearing shale unit with patchy subsoil cover. Geophysical and hydrochemical investigations showed shallower intervals contained hydraulically active fractures where denitrification was reflected through lower nitrogen levels and an isotopic enrichment ratio of 1.7 between δ{sup 15}N and δ{sup 18}O. Study findings highlight the influence of bedrock hydrogeological conditions on aqueous nitrogen mobility. Investigation results demonstrate that bedrock conditions need to be considered when implementing catchment management plans to reduce the impact of agricultural practices on the quality of groundwater and baseflow in receiving rivers. Nitrate isotopic signatures in the groundwater of a freely draining catchment underlain by a karstified aquifer and a poorly draining aquifer with a low transmissivity aquifer. - Graphical abstract: Contrasting nitrate isotope signatures of groundwater in a free draining catchment underlain by a karstified aquifer and a poorly drained catchment underlain by a low transmissivity aquifer. - Highlights: • Comparison of N fate and

Bedrock Hydrogeology-Groundwater flow modelling. Site investigation SFR

International Nuclear Information System (INIS)

Oehman, Johan; Follin, Sven; Oden, Magnus

2013-05-01

The hydrogeological model developed for the SFR extension project (PSU) consists of 40 geologically modelled deformation zones (DZ) and 8 sub-horizontal structural-hydraulic features, called SBAstructures, not defined in the geological model. However, some of the SBA-structures coincide with what is defined as unresolved possible deformation zones (Unresolved PDZ) in the geological modelling. In addition, the hydrogeological model consists of a stochastic discrete fracture network (DFN) model intended for the less fractured rock mass volumes (fracture domains) between the zones and the SBA-structures, and a stochastic fracture model intended to handle remaining Unresolved PDZs in the geological modelling not modelled as SBA-structures in the hydrogeological modelling. The four structural components of the bedrock in the hydrogeological model, i.e. DZ, SBA, Unresolved PDZ and DFN, are assigned hydraulic properties in the hydrogeological model based on the transmissivities interpreted from single-hole hydraulic tests. The main objective of the present work is to present the characteristics of the hydrogeological model with regard to the needs of the forthcoming safety assessment SR-PSU. In concrete words, simulated data are compared with measured data, i.e. hydraulic heads in boreholes and tunnel inflow to the existing repository (SFR). The calculations suggest that the available data for flow model calibration cannot be used to motivate a substantial adjustment of the initial hydraulic parameterisation (assignment of hydraulic properties) of the hydrogeological model. It is suggested that uncertainties in the hydrogeological model are studied in the safety assessment SR-PSU by means of a large number of calculation cases. These should address hydraulic heterogeneity of deterministic structures (DZ and SBA) and realisations of stochastic fractures/fracture networks (Unresolved PDZ and DFN) within the entire SFR Regional model domain

Bedrock Hydrogeology - Groundwater flow modelling. Site investigation SFR

Energy Technology Data Exchange (ETDEWEB)

Oehman, Johan [Geosigma AB, Uppsala (Sweden); Follin, Sven [SF GeoLogic AB, Taeby (Sweden); Oden, Magnus [SKB, Stockholm (Sweden)

2013-05-15

The hydrogeological model developed for the SFR extension project (PSU) consists of 40 geologically modelled deformation zones (DZ) and 8 sub-horizontal structural-hydraulic features, called SBAstructures, not defined in the geological model. However, some of the SBA-structures coincide with what is defined as unresolved possible deformation zones (Unresolved PDZ) in the geological modelling. In addition, the hydrogeological model consists of a stochastic discrete fracture network (DFN) model intended for the less fractured rock mass volumes (fracture domains) between the zones and the SBA-structures, and a stochastic fracture model intended to handle remaining Unresolved PDZs in the geological modelling not modelled as SBA-structures in the hydrogeological modelling. The four structural components of the bedrock in the hydrogeological model, i.e. DZ, SBA, Unresolved PDZ and DFN, are assigned hydraulic properties in the hydrogeological model based on the transmissivities interpreted from single-hole hydraulic tests. The main objective of the present work is to present the characteristics of the hydrogeological model with regard to the needs of the forthcoming safety assessment SR-PSU. In concrete words, simulated data are compared with measured data, i.e. hydraulic heads in boreholes and tunnel inflow to the existing repository (SFR). The calculations suggest that the available data for flow model calibration cannot be used to motivate a substantial adjustment of the initial hydraulic parameterisation (assignment of hydraulic properties) of the hydrogeological model. It is suggested that uncertainties in the hydrogeological model are studied in the safety assessment SR-PSU by means of a large number of calculation cases. These should address hydraulic heterogeneity of deterministic structures (DZ and SBA) and realisations of stochastic fractures/fracture networks (Unresolved PDZ and DFN) within the entire SFR Regional model domain.

Final disposal Forsmark, Simpevarp and Laxemar. Inflow of ground water and influence on hydrogeologic and hydrologic conditions; Slutfoervar Forsmark, Simpevarp och Laxemar. Inlaeckage av grundvatten samt paaverkan paa hydrogeologiska och hydrologiska foerhaallanden

Energy Technology Data Exchange (ETDEWEB)

Werner, Kent [Golder Associates AB, Stockholm (Sweden)

2006-10-15

Laxemar, the results show that also the deep parts of the repository yield an inflow and cause a lowering of the groundwater table. Hence, it is more difficult to decouple the deep and the near surface parts of the repository at these locations. A repository at Simpevarp causes a larger inflow but a smaller area of influence, compared to a repository at Laxemar. This difference is most likely due to that Simpevarp is located by the sea, whereas Laxemar is located further inland. However, there are differences in terms of how grouting is simulated in the DarcyTools modelling of the locations, which makes the comparison difficult. A simple estimate, based on the net recharge (annual mean) at each site shows that the model calculated inflow to a repository at Forsmark corresponds to an area of influence from c 1 km{sup 2} (hydraulic conductivity in the grouted zone K{sub inj} 10{sup -7} m/s) to c 0.3 km{sup 2} (K{sub inj} = 10{sup -9} m/s). For a repository at Simpevarp, the inflow corresponds an area of influence from c 36 km{sup 2} (skin factor = 0.1) to c 1.5 km{sup 2} (skin factor = 0.001); in the Simpevarp modelling, a 'skin factor' was utilized to simulate the grouting. For a repository at Laxemar, a similar comparison provides an area of influence from c 11 km{sup 2} (K{sub inj} = 10{sup -7} m/s) to c 6.5 km{sup 2} (K{sub inj} = 10{sup -9} m/s). Since the modelling results are preliminary, they principally express differences between the locations in terms of their hydrogeological and hydrological characteristics. The results are yet too preliminary to demonstrate the effects of a repository on its surroundings in absolute terms. Examples of uncertainties in the modelling include the representation of the bedrock in the 'bedrock models', providing the basis for the modelling; this particularly applies to the upper parts of the bedrock. Moreover, the interaction between Quaternary deposits and bedrock is identified as an important factor for the

The influence of bedrock hydrogeology on catchment-scale nitrate fate and transport in fractured aquifers.

Science.gov (United States)

Orr, Alison; Nitsche, Janka; Archbold, Marie; Deakin, Jenny; Ofterdinger, Ulrich; Flynn, Raymond

2016-11-01

Characterising catchment scale biogeochemical processes controlling nitrate fate in groundwater constitutes a fundamental consideration when applying programmes of measures to reduce risks posed by diffuse agricultural pollutants to water quality. Combining hydrochemical analyses with nitrate isotopic data and physical hydrogeological measurements permitted characterisation of biogeochemical processes influencing nitrogen fate and transport in the groundwater in two fractured bedrock aquifers with contrasting hydrogeology but comparable nutrient loads. Hydrochemical and isotopic analyses of groundwater samples collected from moderately fractured, diffusely karstified limestone indicated nitrification controlled dissolved nitrogen fate and delivery to aquatic receptors. By contrast nitrate concentrations in groundwater were considerably lower in a low transmissivity highly lithified sandstone and pyrite-bearing shale unit with patchy subsoil cover. Geophysical and hydrochemical investigations showed shallower intervals contained hydraulically active fractures where denitrification was reflected through lower nitrogen levels and an isotopic enrichment ratio of 1.7 between δ(15)N and δ(18)O. Study findings highlight the influence of bedrock hydrogeological conditions on aqueous nitrogen mobility. Investigation results demonstrate that bedrock conditions need to be considered when implementing catchment management plans to reduce the impact of agricultural practices on the quality of groundwater and baseflow in receiving rivers. Nitrate isotopic signatures in the groundwater of a freely draining catchment underlain by a karstified aquifer and a poorly draining aquifer with a low transmissivity aquifer. Copyright © 2016 Elsevier B.V. All rights reserved.

Regional hydrogeological simulations for Forsmark - numerical modelling using DarcyTools. Preliminary site description Forsmark area version 1.2

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-12-15

A numerical model is developed on a regional-scale (hundreds of square kilometres) to study the zone of influence for variable-density groundwater flow that affects the Forsmark area. Transport calculations are performed by particle tracking from a local-scale release area (a few square kilometres) to test the sensitivity to different hydrogeological uncertainties and the need for far-field realism. The main objectives of the regional flow modelling were to achieve the following: I. Palaeo-hydrogeological understanding: An improved understanding of the palaeohydrogeological conditions is necessary in order to gain credibility for the site descriptive model in general and the hydrogeological description in particular. This requires modelling of the groundwater flow from the last glaciation up to present-day with comparisons against measured TDS and other hydro-geochemical measures. II. Simulation of flow paths: The simulation and visualisation of flow paths from a tentative repository area is a means for describing the role of the current understanding of the modelled hydrogeological conditions in the target volume, i.e. the conditions of primary interest for Safety Assessment. Of particular interest here is demonstration of the need for detailed far-field realism in the numerical simulations. The motivation for a particular model size (and resolution) and set of boundary conditions for a realistic description of the recharge and discharge connected to the flow at repository depth is an essential part of the groundwater flow path simulations. The numerical modelling was performed by two separate modelling teams, the ConnectFlow Team and the DarcyTools Team. The work presented in this report was based on the computer code DarcyTools developed by Computer-aided Fluid Engineering. DarcyTools is a kind of equivalent porous media (EPM) flow code specifically designed to treat flow and salt transport in sparsely fractured crystalline rock intersected by transmissive

Regional hydrogeological simulations for Forsmark - numerical modelling using DarcyTools. Preliminary site description Forsmark area version 1.2

International Nuclear Information System (INIS)

Follin, Sven; Stigsson, Martin; Svensson, Urban

2005-12-01

A numerical model is developed on a regional-scale (hundreds of square kilometres) to study the zone of influence for variable-density groundwater flow that affects the Forsmark area. Transport calculations are performed by particle tracking from a local-scale release area (a few square kilometres) to test the sensitivity to different hydrogeological uncertainties and the need for far-field realism. The main objectives of the regional flow modelling were to achieve the following: I. Palaeo-hydrogeological understanding: An improved understanding of the palaeohydrogeological conditions is necessary in order to gain credibility for the site descriptive model in general and the hydrogeological description in particular. This requires modelling of the groundwater flow from the last glaciation up to present-day with comparisons against measured TDS and other hydro-geochemical measures. II. Simulation of flow paths: The simulation and visualisation of flow paths from a tentative repository area is a means for describing the role of the current understanding of the modelled hydrogeological conditions in the target volume, i.e. the conditions of primary interest for Safety Assessment. Of particular interest here is demonstration of the need for detailed far-field realism in the numerical simulations. The motivation for a particular model size (and resolution) and set of boundary conditions for a realistic description of the recharge and discharge connected to the flow at repository depth is an essential part of the groundwater flow path simulations. The numerical modelling was performed by two separate modelling teams, the ConnectFlow Team and the DarcyTools Team. The work presented in this report was based on the computer code DarcyTools developed by Computer-aided Fluid Engineering. DarcyTools is a kind of equivalent porous media (EPM) flow code specifically designed to treat flow and salt transport in sparsely fractured crystalline rock intersected by transmissive

Site description of the SFR area at Forsmark at completion of the site investigation phase. SDM-PSU Forsmark

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-05-15

The site descriptive model (SDM) presented in this report is an integrated model for bedrock geology, rock mechanics, bedrock hydrogeology and bedrock hydrogeochemistry of the site investigated in the SFR extension project (PSU). A description of the surface system is also included in the report. However, the surface system is not integrated with the other disciplines as new data regarding the surface system will not be available until after the completion of SDM-PSU. It is noted that SDM-PSU does not include all disciplines handled in SDM-Site Forsmark (SKB 2008b), the focus is to produce a site description that meets the needs of the SFR extension project. The overall objective of the SFR extension project is to have the application for the extension ready by 2013. This report presents an integrated site model incorporating the historic data acquired from the investigations for and construction of the existing SFR facility (1980-1986), as well as from the recent investigations for the planned extension of SFR (2008-2009). It also provides a summary of the abundant underlying data and the discipline-specific models that support the integrated site model. The description relies heavily on background reports concerning detailed data analyses and modelling in the different disciplines. It is noteworthy that the investigations conducted during the SFR extension project were guided by the choice of site prior to the investigations, which was based on the experience gained during the construction of the existing SFR facility.

Site description of the SFR area at Forsmark at completion of the site investigation phase. SDM-PSU Forsmark

International Nuclear Information System (INIS)

2013-05-01

The site descriptive model (SDM) presented in this report is an integrated model for bedrock geology, rock mechanics, bedrock hydrogeology and bedrock hydrogeochemistry of the site investigated in the SFR extension project (PSU). A description of the surface system is also included in the report. However, the surface system is not integrated with the other disciplines as new data regarding the surface system will not be available until after the completion of SDM-PSU. It is noted that SDM-PSU does not include all disciplines handled in SDM-Site Forsmark (SKB 2008b), the focus is to produce a site description that meets the needs of the SFR extension project. The overall objective of the SFR extension project is to have the application for the extension ready by 2013. This report presents an integrated site model incorporating the historic data acquired from the investigations for and construction of the existing SFR facility (1980-1986), as well as from the recent investigations for the planned extension of SFR (2008-2009). It also provides a summary of the abundant underlying data and the discipline-specific models that support the integrated site model. The description relies heavily on background reports concerning detailed data analyses and modelling in the different disciplines. It is noteworthy that the investigations conducted during the SFR extension project were guided by the choice of site prior to the investigations, which was based on the experience gained during the construction of the existing SFR facility

Site description of Forsmark at completion of the site investigation phase. SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

2008-12-15

The Swedish Nuclear Fuel and Waste Management Co., SKB, has undertaken site characterisation in two different areas, Forsmark and Laxemar-Simpevarp, in order to identify a suitable location for a geological repository of spent nuclear fuel according to the KBS-3 method. The site investigations have been conducted in campaigns, punctuated by data freezes. After each data freeze, the site data have been analysed and modelling has been carried out with the overall purpose to develop a site descriptive model (SDM). The site descriptive model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It is also essential for safety assessment, since the model is the only source for site-specific input. Another important use of the site descriptive model is in the environmental impact assessment. An SDM is an integrated model for geology, thermal properties, rock mechanics, hydrogeology, hydrogeochemistry, bedrock transport properties and a description of the surface system. The site descriptive model compiled in the current report, SDM-Site, presents an integrated understanding of the Forsmark area at the completion of the surface-based investigations, which were conducted at Forsmark during the period 2002 to 2007. It also provides a summary of the abundant underlying data and the discipline-specific models that support the site understanding. The description relies heavily on background reports that address, in particular, details in data analyses and modelling in the different disciplines. The Forsmark area is located in northern Uppland within the municipality of Oesthammar, about 120 km north of Stockholm. The candidate area for site investigation is located along the shoreline of Oeregrundsgrepen, within the north-western part of a major tectonic lens that formed between 1.87 and 1.85 billion years ago during the Svecokarelian orogeny. The candidate area is approximately 6 km long and 2 km wide. The

Site description of Forsmark at completion of the site investigation phase. SDM-Site Forsmark

International Nuclear Information System (INIS)

2008-12-01

The Swedish Nuclear Fuel and Waste Management Co., SKB, has undertaken site characterisation in two different areas, Forsmark and Laxemar-Simpevarp, in order to identify a suitable location for a geological repository of spent nuclear fuel according to the KBS-3 method. The site investigations have been conducted in campaigns, punctuated by data freezes. After each data freeze, the site data have been analysed and modelling has been carried out with the overall purpose to develop a site descriptive model (SDM). The site descriptive model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It is also essential for safety assessment, since the model is the only source for site-specific input. Another important use of the site descriptive model is in the environmental impact assessment. An SDM is an integrated model for geology, thermal properties, rock mechanics, hydrogeology, hydrogeochemistry, bedrock transport properties and a description of the surface system. The site descriptive model compiled in the current report, SDM-Site, presents an integrated understanding of the Forsmark area at the completion of the surface-based investigations, which were conducted at Forsmark during the period 2002 to 2007. It also provides a summary of the abundant underlying data and the discipline-specific models that support the site understanding. The description relies heavily on background reports that address, in particular, details in data analyses and modelling in the different disciplines. The Forsmark area is located in northern Uppland within the municipality of Oesthammar, about 120 km north of Stockholm. The candidate area for site investigation is located along the shoreline of Oeregrundsgrepen, within the north-western part of a major tectonic lens that formed between 1.87 and 1.85 billion years ago during the Svecokarelian orogeny. The candidate area is approximately 6 km long and 2 km wide. The

Hydrogeological bedrock inferred from electrical resistivity model in Taichung Basin, Taiwan

Science.gov (United States)

Chiang, C. W.; Chang, P. Y.; Chang, L. C.

2015-12-01

The four-year project of the study of groundwater hydrogeology and recharge model was indicated by Central Geological Survey, MOEA, Taiwan (R.O.C.) to evaluate recharge groundwater areas in Taiwan where included Taipei, Taichung Basins, Lanyang and Chianan Plains. The groundwater recharge models of Lanyang Plain and Taipei Basin have successfully been estimated in two years ago (2013-2014). The third year of the project integrates with geophysical, geochemistry, and hydrogeology models to estimate the groundwater recharge model in Taichung Basin region. Taichung Basin is mainly covered by Pre-Pleistocene of thick gravel, sandy and muddy sediment rocks within a joint alluvial fan, whereas the depth of the hydrological bedrock remains uncertain. Two electrical resistivity geophysical tools were carried out utilizing direct current resistivity and audio-magnetotelluric (AMT) explorations, which could ideally provide the depth resolutions from shallow to depth for evaluating the groundwater resources. The study has carried out 21 AMT stations in the southern Taichung Basin in order to delineate hydrological bedrock in the region. All the AMT stations were deployed about 24 hours and processed with remote reference technique to reduce culture noises. The quality of most stations shows acceptable in the area which two stations were excluded due to near-field source effect in the southwestern basin. The best depth resolution is identified in 500 meters for the model. The preliminary result shows that the depths of the bedrock gradually changes from southern ~20 m toward to ~400 m in central, and eastern ~20 m to 180 m in the western basin inferred from the AMT model. The investigation shows that AMT method could be a useful geophysical tool to enhance the groundwater recharge model estimation without dense loggings in the region.

Reflection seismic studies in the Forsmark area - stage 1

Energy Technology Data Exchange (ETDEWEB)

Juhlin, Christopher; Bergman Bjoern; Palm, Hans [Uppsala Univ. (Sweden). Dept. of Earth Sciences

2002-10-01

Reflection seismic data were acquired in the Spring of 2002 in the Forsmark area, located about 70 km northeast of Uppsala, Sweden. The Forsmark area has been targeted by SKB as a possible storage site for high level radioactive waste. About 16 km of high resolution seismic data were acquired along five separate profiles varying in length from 2 to 5 km. Non-final source and receiver spacing was 10 m with 100 active channels when recording data from a dynamite source (15-75 g). The profiles were located within a relatively undeformed lens of bedrock that trends in the NW-SE direction. The lens is surrounded by highly deformed rock on all sides. In conjunction with the reflection component of the study, all shots were also recorded on up to eleven 3-component fixed Orion seismographs. These recordings provided long offset data from which a velocity model of the uppermost 400 m of bedrock could be derived. Results from the study show that the bedrock has been well imaged down to depths of at least 3 km. The upper 1000 m of bedrock is much more reflective in the southeastern portion of the lens compared to the northwestern part close to the Forsmark reactors. This is interpreted as the bedrock being more homogeneous in the northwest. However, a major reflective zone (the A1 reflector) is interpreted to dip to the S-SE below this homogeneous bedrock. In the southeastern portion of the lens the orientation of the reflectors is well determined where the profiles cross one another. The general strike of the major reflectors is NE-SW with dips of 20-35 degrees to the southeast.

Hydrogeochemical evaluation. Preliminary site description Forsmark area - version 1.2

International Nuclear Information System (INIS)

Laaksoharju, Marcus

2005-03-01

Siting studies for SKB's programme of deep geological disposal of nuclear fuel waste currently involves the investigation of two locations, Forsmark and Laxemar-Simpevarp, on the eastern coast of Sweden to determine their geological, hydrogeochemical and hydrogeological characteristics. Present work completed has resulted in Model version 1.2 which represents the second evaluation of the available Forsmark groundwater analytical data collected up to June, 2004. The Hydrochemical Analytical Group (HAG) had access to data where a total of 1,131 water samples had been collected from the surface and sub-surface environment; 252 samples were collected from drilled boreholes. The deepest fracture groundwater samples with sufficient analytical data reflected depths down to 1 km. Most of the waters sampled (66%) lacked crucial analytical information that restricted the evaluation. Model version 1.2 focuses on geochemical and mixing processes affecting the groundwater composition in the uppermost part of the bedrock, down to repository levels, and eventually extending to 1,000 m depth. The complex groundwater evolution and patterns at Forsmark are a result of many factors such as: a) the present-day topography and proximity to the Baltic Sea, b) past changes in hydrogeology related to glaciation/deglaciation, land uplift and repeated marine/lake water regressions/ transgressions, and c) organic or inorganic alteration of the groundwater composition caused by microbial processes or water/rock interactions. The sampled groundwaters reflect to various degrees processes relating to modern or ancient water/rock interactions and mixing. The groundwater flow regimes at Forsmark are considered local and extend down to depths of around 600 m depending on hydraulic conditions. Close to the Baltic Sea coastline where topographical variation is even less, groundwater flow penetration to depth will subsequently be less marked and such areas will tend to be characterised by groundwater

Hydrogeochemical evaluation. Preliminary site description Forsmark area - version 1.2

Energy Technology Data Exchange (ETDEWEB)

Laaksoharju, Marcus (ed.) [Geopoint AB, Stockholm (Sweden)

2005-03-15

Siting studies for SKB's programme of deep geological disposal of nuclear fuel waste currently involves the investigation of two locations, Forsmark and Laxemar-Simpevarp, on the eastern coast of Sweden to determine their geological, hydrogeochemical and hydrogeological characteristics. Present work completed has resulted in Model version 1.2 which represents the second evaluation of the available Forsmark groundwater analytical data collected up to June, 2004. The Hydrochemical Analytical Group (HAG) had access to data where a total of 1,131 water samples had been collected from the surface and sub-surface environment; 252 samples were collected from drilled boreholes. The deepest fracture groundwater samples with sufficient analytical data reflected depths down to 1 km. Most of the waters sampled (66%) lacked crucial analytical information that restricted the evaluation. Model version 1.2 focuses on geochemical and mixing processes affecting the groundwater composition in the uppermost part of the bedrock, down to repository levels, and eventually extending to 1,000 m depth. The complex groundwater evolution and patterns at Forsmark are a result of many factors such as: a) the present-day topography and proximity to the Baltic Sea, b) past changes in hydrogeology related to glaciation/deglaciation, land uplift and repeated marine/lake water regressions/ transgressions, and c) organic or inorganic alteration of the groundwater composition caused by microbial processes or water/rock interactions. The sampled groundwaters reflect to various degrees processes relating to modern or ancient water/rock interactions and mixing. The groundwater flow regimes at Forsmark are considered local and extend down to depths of around 600 m depending on hydraulic conditions. Close to the Baltic Sea coastline where topographical variation is even less, groundwater flow penetration to depth will subsequently be less marked and such areas will tend to be characterised by

Updated strategy and test of new concepts for groundwater flow modelling in Forsmark in preparation of site descriptive modelling stage 2.2

Energy Technology Data Exchange (ETDEWEB)

Follin, Sven [SF GeoLogic AB (Sweden); Johansson, Per-Olof [Artesia Grundvattenkonsult AB (Sweden); Leven, Jakob [Geosigma AB (Sweden); Hartley, Lee; Holton, David; McCarthy, Rachel; Roberts, David [Serco Assurance (United Kingdom)

2007-01-15

As part of the preliminary Site Descriptive Modelling (SDM version 1.2) for the Initial Site Investigation (ISI) stage at Forsmark, Simpevarp and Laxemar, a methodology was developed for constructing hydrogeological models of the crystalline bedrock. The methodology achieved reasonable success given the restricted amounts and types of data available at the time. Notwithstanding, several issues of concern have surfaced following the reviews of the preliminary site descriptions of the three sites. Possible solutions to parts of the problems have been discussed internally for a longer time and an integrated view and strategy forward has been formulated. The 'new strategy' is not a complete shift in methodology, however, but a refocusing on and clarification of the key aspects that the hydrogeological SDM needs to accomplish. In broad terms the basic principle of the 'new strategy' suggested is to develop an overall conceptual model that first establishes the major flowing deformation zones, and then gradually approaches determination of the hydraulic properties of the bedrock outside these zones in the potential repository volume. On each scale, the focus of the description should be on features/structures of significance on that scale. Clearly, a detailed (although statistical) description of the repository and canister deposition hole scale is the end goal, but this approach (which also is more the traditional approach in hydrogeology) is judged to provide a much better motivated overall geometrical description. Furthermore, the 'new strategy' puts more emphasis on field testing (e.g. interference tests) and data analyses and less on numerical simulation and calibration. That is, before extensive (and costly) simulations and model calibrations are made it needs to be clearly understood what could be the potential gains of carrying them out. This report presents the conceptual model development for Forsmark in preparation of the site

Site descriptive modelling Forsmark, stage 2.2. A fracture domain concept as a basis for the statistical modelling of fractures and minor deformation zones, and interdisciplinary coordination

Energy Technology Data Exchange (ETDEWEB)

Olofsson, Isabelle; Simeonov, Assen [Swedish Nuclear Fuel and Waste Manageme nt Co., Stockholm (Sweden); Stephens, Michael [Geological Survey of Sweden (SGU), U ppsala (Sweden); Follin, Sven [SF GeoLogic AB, Taeby (Sweden); Nilsson, Ann-Chatrin [G eosigma AB, Uppsala (Sweden); Roeshoff, Kennert; Lindberg, Ulrika; Lanaro, Flavio [Bergbygg konsult AB, Haesselby (Sweden); Fredriksson, Anders; Persson, Lars [Golder Associat es AB (Sweden)

2007-04-15

The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterization at two different locations, Forsmark and Simpevarp/Laxemar, with the objective of siting a final waste repository at depth for spent nuclear fuel. The programme is built upon the development of site descriptive models after each data freeze. This report describes the first attempt to define fracture domains for the Forsmark site modelling in stage 2.2. Already during model version 1.2 at Forsmark, significant spatial variability in the fracture pattern was observed. The variability appeared to be so significant that it provoked the need for a subdivision of the model volume for the treatment of geological and hydrogeological data into sub-volumes. Subsequent analyses of data collected up to data freeze 2.1 led to a better understanding of the site and a concept for the definition of fracture domains based on geological characteristics matured. The main objectives of this report are to identify and describe fracture domains at the site on the basis of geological data and to compile hydrogeological, hydrogeochemical and rock mechanics data within each fracture domain and address the implications of this integration activity. On the basis of borehole data, six fracture domains (FFM01-FFM06) have been recognized inside and immediately around the candidate volume. Three of these domains (FFM01, FFM02 and FFM06) lie inside the target volume for a potential repository in the northwestern part of the candidate area, and need to be addressed in the geological DFN modelling work. The hydrogeological data support the subdivision of the bedrock into fracture domains FFM01, FFM02 and FFM03. Few or no data are available for the other three domains. The hydrogeochemical data also support the subdivision into fracture domains FFM01 and FFM02. Since few data are available from the bedrock between deformation zones inside FFM03, there is little information on the hydrogeochemical

Hydrogeochemical evaluation of the Forsmark site, model version 1.1

Energy Technology Data Exchange (ETDEWEB)

Laaksoharju, Marcus (ed.) [GeoPoint AB, Sollentuna (Sweden); Gimeno, Maria; Auque, Luis; Gomez, Javier [Univ. of Zaragoza (Spain). Dept. of Earth Sciences; Smellie, John [Conterra AB, Uppsala (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden); Gurban, Ioana [3D-Terra, Montreal (Canada)

2004-01-01

Siting studies for SKB's programme of deep geological disposal of nuclear fuel waste currently involves the investigation of two locations, Forsmark and Simpevarp, on the eastern coast of Sweden to determine their geological, geochemical and hydrogeological characteristics. Present work completed has resulted in model version 1.1 which represents the first evaluation of the available Forsmark groundwater analytical data collected up to May 1, 2003 (i.e. the first 'data freeze'). The HAG group had access to a total of 456 water samples collected mostly from the surface and sub-surface environment (e.g. soil pipes in the overburden, streams and lakes); only a few samples were collected from drilled boreholes. The deepest samples reflected depths down to 200 m. Furthermore, most of the waters sampled (74%) lacked crucial analytical information that restricted the evaluation. Consequently, model version 1.1 focussed on the processes taking place in the uppermost part of the bedrock rather than at repository levels. The complex groundwater evolution and patterns at Forsmark are a result of many factors such as: a) the flat topography and closeness to the Baltic Sea resulting in relative small hydrogeological driving forces which can preserve old water types from being flushed out, b) the changes in hydrogeology related to glaciation/deglaciation and land uplift, c) repeated marine/lake water regressions/transgressions, and d) organic or inorganic alteration of the groundwater caused by microbial processes or water/rock interactions. The sampled groundwaters reflect to various degrees modern or ancient water/rock interactions and mixing processes. Based on the general geochemical character and the apparent age two major water types occur in Forsmark: fresh-meteoric waters with a bicarbonate imprint and low residence times (tritium values above detection limit), and brackish-marine waters with Cl contents up to 6,000 mg/L and longer residence times (tritium

Quantitative assessment of radionuclide retention in the near-surface system at Forsmark. Development of a reactive transport model using Forsmark 1.2 data

International Nuclear Information System (INIS)

Grandia, Fidel; Sena, Clara; Arcos, David; Molinero, Jorge; Duro, Lara; Bruno, Jordi

2007-12-01

The main objective of this work is to assess the migration behaviour of selected long-lived radionuclides through the near-surface system of Forsmark, with special focus on the evaluation of the capacity of the Quaternary deposits and sediments for radionuclide retention. The work reported here is based on data and information from Forsmark Site Descriptive Model version 1.2. From the geological point of view, the near-surface systems in the Forsmark area consist of Quaternary deposits and sediments that overlay the granitic bedrock. Glacial till is the more abundant outcropping Quaternary deposit and the remainder is made of clayey deposits. These types of near-surface sediments show distinctive hydraulic and geochemical features. The main reactive mineral in the till deposits, for the time horizons considered in this work, is calcium carbonate together with minor amounts of clay minerals (e.g. illite). The till deposits forms aquifers with relatively high hydraulic conductivities. In contrast, glacial and post-glacial clays are basically composed of illite with low to very low amounts of calcium carbonate, and containing organic matter-rich layers (gyttja), which can promote reducing conditions in the porewaters. All these clays exhibits relatively low hydraulic conductivity values. Five radionuclides have been selected for conceptualization and qualitative evaluation of retention process: U as an actinide, Se as a redox-sensitive radionuclide, Cs as a monovalent cation, Sr as a divalent cation, and I as an anion radionuclide. Overall, radionuclide retention capacity in the surface systems at Forsmark can be provided by sorption on charged surfaces of clays and oxyhydroxides, co-precipitation with sulphates, sulphides, oxyhydroxides and carbonates, and sorption on organic matter. Two-dimensional coupled hydrogeological and reactive solute transport models have been developed to simulate the geochemical behaviour of U, Cs and Sr. These three radionuclides have

Forsmark site investigation. Searching for evidence of late- or postglacial faulting in the Forsmark region. Results from 2002-2004

Energy Technology Data Exchange (ETDEWEB)

Lagerbaeck, Robert; Sundh, Martin; Svedlund, Jan-Olov; Johansson, Helena [Geological Survey of Sweden, Uppsala (Sweden)

2005-10-15

that strong currents were responsible for significant erosion of the bed of the ancient sea. Together with sliding, this erosion resulted in extensive redistribution of sediments and in a substantial levelling of the terrain. The discovery of apparently freshly fractured bedrock within the candidate area at Forsmark raised the question of the origin and significance of the features. The spatial and temporal relationships between this fracturing, still more intensely disrupted bedrock exposures and an extreme abundance of glacially transported boulders in the vicinities suggest that a phase of greatly intensified fracturing and quarrying occurred during a late stage of deglaciation. Field evidence clearly indicates that in parts of the investigation area the surficial bedrock, previously protruding bedrock knobs included, were disrupted and transformed into sheets of boulders.

Forsmark site investigation. Searching for evidence of late- or postglacial faulting in the Forsmark region. Results from 2002-2004

International Nuclear Information System (INIS)

Lagerbaeck, Robert; Sundh, Martin; Svedlund, Jan-Olov; Johansson, Helena

2005-10-01

currents were responsible for significant erosion of the bed of the ancient sea. Together with sliding, this erosion resulted in extensive redistribution of sediments and in a substantial levelling of the terrain. The discovery of apparently freshly fractured bedrock within the candidate area at Forsmark raised the question of the origin and significance of the features. The spatial and temporal relationships between this fracturing, still more intensely disrupted bedrock exposures and an extreme abundance of glacially transported boulders in the vicinities suggest that a phase of greatly intensified fracturing and quarrying occurred during a late stage of deglaciation. Field evidence clearly indicates that in parts of the investigation area the surficial bedrock, previously protruding bedrock knobs included, were disrupted and transformed into sheets of boulders

Quantitative assessment of radionuclide retention in the near-surface system at Forsmark. Development of a reactive transport model using Forsmark 1.2 data

Energy Technology Data Exchange (ETDEWEB)

Grandia, Fidel; Sena, Clara; Arcos, David; Molinero, Jorge; Duro, Lara; Bruno, Jordi (Amphos XXI Consulting S.L., Barcelona (Spain))

2007-12-15

The main objective of this work is to assess the migration behaviour of selected long-lived radionuclides through the near-surface system of Forsmark, with special focus on the evaluation of the capacity of the Quaternary deposits and sediments for radionuclide retention. The work reported here is based on data and information from Forsmark Site Descriptive Model version 1.2. From the geological point of view, the near-surface systems in the Forsmark area consist of Quaternary deposits and sediments that overlay the granitic bedrock. Glacial till is the more abundant outcropping Quaternary deposit and the remainder is made of clayey deposits. These types of near-surface sediments show distinctive hydraulic and geochemical features. The main reactive mineral in the till deposits, for the time horizons considered in this work, is calcium carbonate together with minor amounts of clay minerals (e.g. illite). The till deposits forms aquifers with relatively high hydraulic conductivities. In contrast, glacial and post-glacial clays are basically composed of illite with low to very low amounts of calcium carbonate, and containing organic matter-rich layers (gyttja), which can promote reducing conditions in the porewaters. All these clays exhibits relatively low hydraulic conductivity values. Five radionuclides have been selected for conceptualization and qualitative evaluation of retention process: U as an actinide, Se as a redox-sensitive radionuclide, Cs as a monovalent cation, Sr as a divalent cation, and I as an anion radionuclide. Overall, radionuclide retention capacity in the surface systems at Forsmark can be provided by sorption on charged surfaces of clays and oxyhydroxides, co-precipitation with sulphates, sulphides, oxyhydroxides and carbonates, and sorption on organic matter. Two-dimensional coupled hydrogeological and reactive solute transport models have been developed to simulate the geochemical behaviour of U, Cs and Sr. These three radionuclides have

Comparison of site descriptive models for Olkiluoto, Finland and Forsmark, Sweden

Energy Technology Data Exchange (ETDEWEB)

Geier, J.; Bath, A.; Stephansson, O.; Luukkonen, A.

2012-08-15

The proposed high-level radioactive waste repository sites at Olkiluoto and Forsmark share broadly similar geologic histories and regional settings. Despite differences in lithology, rock strength and patterns of brittle deformation, the sites show similarities in terms of hydrogeochemistry and hydrogeology. These similarities reflect a dominating influence of saline and brackish water intrusion during inundation by the postglacial Littorina Sea and Baltic Sea, followed by exposure to meteoric waters following postglacial uplift and transition to a Baltic coastal setting. Both sites also contain deep bedrock saline groundwater, though this is more evident at Olkiluoto than at Forsmark. A comparative study of site descriptive models for the two sites identifies the following key differences that could potentially impact safety of a repository: (1) Redox controls, buffering and biogeochemistry at proposed repository depths; (2) Salinity gradients at and below proposed repository depths; (3) Methane concentrations at and below proposed repository depths; (4) Depths to which glacial water and Littorina water penetrated; (5) Cation hydrogeochemistry and water-rock reaction; (6) Pore water compositions in rock matrix; (7) Rock fabric, secondary minerals and alteration with respect to radionuclide retention; (8) Brittle deformation fabric differences on multiple scales that affect vertical hydraulic conductivity; (9) Differences in apparent frequency of encountering water-conducting networks at proposed repository depths; (10) Shallow bedrock hydraulic properties; (11) Unique intrusive or dissolution features; (12) Connectivity of site-scale models to regional-scale features; (13) Mesoproterozoic rocks in vicinity and possibilities for human-intrusion scenarios; (14) Rock stresses and bedrock strength and deformability at proposed repository depths; (15) Thermal anisotropy. These differences are all potentially significant to safety functions, but none are so severe that

Groundwater flow modelling of periods with temperate climate conditions - Forsmark

Energy Technology Data Exchange (ETDEWEB)

Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Swan, David (Serco Technical Consulting Services (United Kingdom)); Marsic, Niko (Kemakta Konsult AB (Sweden)); Follin, Sven (SF GeoLogic AB (Sweden))

2010-11-15

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different climate conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Forsmark site during temperate conditions; i.e. from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 12,000 AD. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a hydrogeological base case (reference case conceptualisation) and then in an examination of various areas of uncertainty within the current understanding by a series of model variants. The hydrogeological base case models at three different scales, 'repository', 'site' and 'regional', make use of continuous porous medium (CPM), equivalent continuous porous medium (ECPM) and discrete fracture network (DFN) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

Hydraulic effects of unsealed boreholes. Numerical groundwater flow modelling of the Forsmark and Laxemar sites

International Nuclear Information System (INIS)

Bockgaard, Niclas

2011-06-01

The objective of the work was to investigate hydraulic effects of open and poorly sealed boreholes on groundwater flow conditions through simulations using a numerical groundwater model. Specifically, the boreholes KFM07A, KFM09A, and KFM09B in Forsmark and the boreholes KLX04, KLX06, and KLX10 in Laxemar were studied. The criteria for the selection of these boreholes were that the boreholes should represent typical conditions of the site, the borehole length should exceed 500 m, and that several major fractured zones should be intersected. The boreholes KFM07A and KLX06, respectively, were selected as reference boreholes for more detailed studies of different sealing schemes. The model setup of the Forsmark model followed the Forsmark 2.2 regional-scale conceptual hydrogeological model. The model domain was approximately 15 km (north-south) x 10 km (west- east) x 1.2 km (depth). The 131 deformation zones and three layers of superficial horizontal sheet joint were modelled deterministically. A stochastic discrete fracture network (DFN) representing fractures and minor deformation zones were also generated between the deterministic deformation zones inside central model volume. The side lengths of the square fractures were from 1,000 m down to 10 m. In order to resolve the details of flow in to and out from the borehole, a more detailed DFN was generated in a zone around the borehole KFM07A, where fractures down to a side length of 0.5 m were considered. The model setup of the Laxemar model followed the SDM-Site Laxemar (Laxemar 2.3) regional scale conceptual hydrogeological model. The model domain was approximately 12 km (north-south) x 20 km (west-east) x 2.1 km (depth). A number of 71 deformation zones were modelled deterministically, and one realization of a stochastic DFN, the so-called hydrogeological DFN model base case, was imported to the model. Similar to the Forsmark case, a more detailed DFN was also generated around the reference borehole KLX06. The

Hydraulic effects of unsealed boreholes. Numerical groundwater flow modelling of the Forsmark and Laxemar sites

Energy Technology Data Exchange (ETDEWEB)

Bockgaard, Niclas [Golder Associates AB, Stockholm (Sweden)

2011-06-15

The objective of the work was to investigate hydraulic effects of open and poorly sealed boreholes on groundwater flow conditions through simulations using a numerical groundwater model. Specifically, the boreholes KFM07A, KFM09A, and KFM09B in Forsmark and the boreholes KLX04, KLX06, and KLX10 in Laxemar were studied. The criteria for the selection of these boreholes were that the boreholes should represent typical conditions of the site, the borehole length should exceed 500 m, and that several major fractured zones should be intersected. The boreholes KFM07A and KLX06, respectively, were selected as reference boreholes for more detailed studies of different sealing schemes. The model setup of the Forsmark model followed the Forsmark 2.2 regional-scale conceptual hydrogeological model. The model domain was approximately 15 km (north-south) x 10 km (west- east) x 1.2 km (depth). The 131 deformation zones and three layers of superficial horizontal sheet joint were modelled deterministically. A stochastic discrete fracture network (DFN) representing fractures and minor deformation zones were also generated between the deterministic deformation zones inside central model volume. The side lengths of the square fractures were from 1,000 m down to 10 m. In order to resolve the details of flow in to and out from the borehole, a more detailed DFN was generated in a zone around the borehole KFM07A, where fractures down to a side length of 0.5 m were considered. The model setup of the Laxemar model followed the SDM-Site Laxemar (Laxemar 2.3) regional scale conceptual hydrogeological model. The model domain was approximately 12 km (north-south) x 20 km (west-east) x 2.1 km (depth). A number of 71 deformation zones were modelled deterministically, and one realization of a stochastic DFN, the so-called hydrogeological DFN model base case, was imported to the model. Similar to the Forsmark case, a more detailed DFN was also generated around the reference borehole KLX06. The

Surface system Forsmark. Site descriptive modelling SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Lindborg, Tobias [ed.

2008-12-15

SKB has undertaken site characterization of two different areas, Forsmark and Laxemar-Simpevarp, in order to find a suitable location for a geological repository for spent nuclear fuel. This report focuses on the site descriptive modelling of the surface system at Forsmark. The characterization of the surface system at the site was primarily made by identifying and describing important properties in different parts of the surface system, properties concerning e.g. hydrology and climate, Quaternary deposits and soils, hydrochemistry, vegetation, ecosystem functions, but also current and historical land use. The report presents available input data, methodology for data evaluation and modelling, and resulting models for each of the different disciplines. Results from the modelling of the surface system are also integrated with results from modelling of the deep bedrock system. The Forsmark site is located within the municipality of Oesthammar, about 120 km north of Stockholm. The investigated area is located along the shoreline of Oeregrundsgrepen, a funnel-shaped bay of the Baltic Sea. The area is characterized by small-scale topographic variations and is almost entirely located at altitudes lower than 20 metres above sea level. The Quaternary deposits in the area are dominated by till, characterized by a rich content of calcite which was transported by the glacier ice to the area from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. As a result, the surface waters and shallow groundwater at Forsmark are characterized by high pH values and high concentrations of certain major constituents, especially calcium and bicarbonate. The annual precipitation and runoff are 560 and 150 mm, respectively. The lakes are small and shallow, with mean and maximum depths ranging from approximately 0.1 to 1 m and 0.4 to 2 m. Sea water flows into the most low-lying lakes during events giving rise to very high sea levels. Wetlands are frequent and cover 25 to 35

Oskarshamn site investigation. Bedrock geology - overview and excursion guide

Energy Technology Data Exchange (ETDEWEB)

Wahlgren, Carl-Henric (Geological Survey of Sweden, Uppsala (Sweden))

2010-09-15

Bearing in mind the significance of the bedrock data from the ground surface for the geological 3D modelling work, SKB decided to present excursion guides that serve in the demonstration of the bedrock geology at the ground surface in both the Forsmark and Laxemar-Simpevarp (this guide) areas. An excursion guide is also available for the Olkiluoto area in south-western Finland, which has been selected for the construction of a repository for the disposal of highly radioactive, spent nuclear fuel. The current excursion guide presents the bedrock geology and describes in detail the character of the bedrock at eight representative outcrops or outcrop areas at the ground surface in the site investigation area at Laxemar-Simpevarp and at one locality north of this area, i.e. at a total of nine localities

Oskarshamn site investigation. Bedrock geology - overview and excursion guide

International Nuclear Information System (INIS)

Wahlgren, Carl-Henric

2010-09-01

Bearing in mind the significance of the bedrock data from the ground surface for the geological 3D modelling work, SKB decided to present excursion guides that serve in the demonstration of the bedrock geology at the ground surface in both the Forsmark and Laxemar-Simpevarp (this guide) areas. An excursion guide is also available for the Olkiluoto area in south-western Finland, which has been selected for the construction of a repository for the disposal of highly radioactive, spent nuclear fuel. The current excursion guide presents the bedrock geology and describes in detail the character of the bedrock at eight representative outcrops or outcrop areas at the ground surface in the site investigation area at Laxemar-Simpevarp and at one locality north of this area, i.e. at a total of nine localities

Recharge and discharge of near-surface groundwater in Forsmark. Comparison of classification methods

International Nuclear Information System (INIS)

Werner, Kent; Johansson, Per-Olof; Brydsten, Lars; Bosson, Emma; Berglund, Sten

2007-03-01

This report presents and compares data and models for identification of near-surface groundwater recharge and discharge (RD) areas in Forsmark. The general principles of groundwater recharge and discharge are demonstrated and applied to interpret hydrological and hydrogeological observations made in the Forsmark area. 'Continuous' RD classification methods considered in the study include topographical modelling, map overlays, and hydrological-hydrogeological flow modelling. 'Discrete' (point) methods include field-based and hydrochemistry-based RD classifications of groundwater monitoring well locations. The topographical RD modelling uses the digital elevation model as the only input. The map overlays use background maps of Quaternary deposits, soils, and ground- and field layers of the vegetation/land use map. Further, the hydrological-hydrogeological modelling is performed using the MIKE SHE-MIKE 11 software packages, taking into account e.g. topography, meteorology, hydrogeology, and geometry of watercourses and lakes. The best between-model agreement is found for the topography-based model and the MIKE SHE-MIKE 11 model. The agreement between the topographical model and the map overlays is less good. The agreement between the map overlays on the one hand, and the MIKE SHE and field-based RD classifications on the other, is thought to be less good, as inferred from the comparison made with the topography-based model. However, much improvement of the map overlays can likely be obtained, e.g. by using 'weights' and calibration (such exercises were outside the scope of the present study). For field-classified 'recharge wells', there is a good agreement to the hydrochemistry-based (Piper plot) well classification, but less good for the field-classified 'discharge wells'. In addition, the concentration of the age-dating parameter tritium shows low variability among recharge wells, but a large spread among discharge wells. The usefulness of hydrochemistry-based RD

Rock Mechanics Forsmark. Site descriptive modelling Forsmark stage 2.2

Energy Technology Data Exchange (ETDEWEB)

Glamheden, Rune; Fredriksson, Anders (Golder Associates AB (SE)); Roeshoff, Kennert; Karlsson, Johan (Berg Bygg Konsult AB (SE)); Hakami, Hossein (Itasca Geomekanik AB (SE)); Christiansson, Rolf (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE))

2007-12-15

The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterisation at two different locations, Forsmark and Laxemar/Simpevarp, with the objective of siting a geological repository for spent nuclear fuel. The characterisation of a site is an integrated work carried out by several disciplines including geology, rock mechanics, thermal properties, hydrogeology, hydrogeochemistry and surface systems. This report presents the rock mechanics model of the Forsmark site up to stage 2.2. The scope of work has included compilation and analysis of primary data of intact rock and fractures, estimation of the rock mass mechanical properties and estimation of the in situ state of stress at the Forsmark site. The laboratory results on intact rock and fractures in the target volume demonstrate a good quality rock mass that is strong, stiff and relatively homogeneous. The homogeneity is also supported by the lithological and the hydrogeological models. The properties of the rock mass have been initially estimated by two separate modelling approaches, one empirical and one theoretical. An overall final estimate of the rock mass properties were achieved by integrating the results from the two models via a process termed 'Harmonization'. Both the tensile tests, carried out perpendicular and parallel to the foliation, and the theoretical analyses of the rock mass properties in directions parallel and perpendicular to the major principal stress, result in parameter values almost independent of direction. This indicates that the rock mass in the target volume is isotropic. The rock mass quality in the target volume appears to be of high and uniform quality. Those portions with reduced rock mass quality that do exist are mainly related to sections with increased fracture frequency. Such sections are associated with deformation zones according to the geological description. The results of adjacent rock domains and fracture domains of the target

Forsmark - site descriptive model version 0

International Nuclear Information System (INIS)

2002-10-01

biosphere, is sufficiently advanced for some initial modelling exercises. The available information on the geosphere in the Forsmark regional model area is quite extensive, at least locally (especially SFR). In order to develop and test the modelling procedures, this information has been collected and transformed into appropriate formats under four separate headings: Geology, Rock mechanics, Hydrogeology, and Hydrogeochemistry. In the areas of rock engineering, hydrogeology and hydrogeochemistry, modelling activities were mainly confined to parametrisation exercises, using presently available data from the Forsmark regional model area to put limits on, for instance, the in situ stress field, the mechanical properties of the rock mass, the hydraulic properties of the fracture zones and rock mass between them, and the hydrogeochemical evolution. The site descriptive model, version 0, is intended as the basic platform and natural starting point for all groups involved in the site investigations at Forsmark, especially for the regional model area. The main results of the present project were to focus attention on the strengths and weaknesses in the available data coverage and data storage and processing systems, and to provide a basis for developing and testing ways of transforming diverse types of geoscientific information into a form appropriate for modelling. At the same time, the project provided concrete guidelines for the planning of the initial site investigations at Forsmark

Forsmark site investigation. A deformation analysis of the Forsmark GPS monitoring network from 2005 to 2009

Energy Technology Data Exchange (ETDEWEB)

Gustafson, Lars; Ljungberg, Annika (Caliterra AB (Sweden))

2010-10-15

The objective of the study is to identify possible movements in the bedrock within and outside the candidate area at Forsmark. Seven physically stable stations were built in the Forsmark area in the autumn of 2005. Stations were established within a ten-kilometer radius. The stations were placed in three different areas separated by regional deformation zones: NE of the Singoe zone, within the candidate area, and SW of the Forsmark zone. Data have been collected in eighteen campaigns, each with a duration of about five days, from November 2005 to December 2009. Stations consist of a stainless steel rod fixed in the bedrock on which the GPS antenna mounts. Each station has dedicated GPS equipment only used at the specific site. Sets consist of a GPS receiver collecting raw GPS data and a choke ring antenna linked to the receiver using a coaxial cable. The receivers and antennas are dual frequency high precision geodetic grade. During each campaign the GPS receiver saves a reading every second for the duration of the five days campaign. The antennas remain mounted on the stations during the entire project, whereas all other equipment is in place at the station only during the campaigns. The measurements were related to the SWEPOS network stations Lovoe, Uppsala and Maartsbo that are defined as stations with stable fundaments by the National Land Survey of Sweden (Lantmaeteriet). This report deals with altogether 18 campaigns. The first 13 campaigns were performed during the period November 2005 to August 2008. However, the number of campaigns has been extended by adding a fourth year to the project. Optimization of the data processing depends on the properties of the entire data set comprising a period of four years. We divided the data into periods of 24 hours with each period processed as a separate session in the Bernese post processing software, after which we analyzed the residuals to conclude that data are of the expected quality. The entire data set from four

Forsmark - site descriptive model version 0

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-10-01

biosphere, is sufficiently advanced for some initial modelling exercises. The available information on the geosphere in the Forsmark regional model area is quite extensive, at least locally (especially SFR). In order to develop and test the modelling procedures, this information has been collected and transformed into appropriate formats under four separate headings: Geology, Rock mechanics, Hydrogeology, and Hydrogeochemistry. In the areas of rock engineering, hydrogeology and hydrogeochemistry, modelling activities were mainly confined to parametrisation exercises, using presently available data from the Forsmark regional model area to put limits on, for instance, the in situ stress field, the mechanical properties of the rock mass, the hydraulic properties of the fracture zones and rock mass between them, and the hydrogeochemical evolution. (abstract truncated)

Surface system Forsmark. Site descriptive modelling SDM-Site Forsmark

International Nuclear Information System (INIS)

Lindborg, Tobias

2008-12-01

SKB has undertaken site characterization of two different areas, Forsmark and Laxemar-Simpevarp, in order to find a suitable location for a geological repository for spent nuclear fuel. This report focuses on the site descriptive modelling of the surface system at Forsmark. The characterization of the surface system at the site was primarily made by identifying and describing important properties in different parts of the surface system, properties concerning e.g. hydrology and climate, Quaternary deposits and soils, hydrochemistry, vegetation, ecosystem functions, but also current and historical land use. The report presents available input data, methodology for data evaluation and modelling, and resulting models for each of the different disciplines. Results from the modelling of the surface system are also integrated with results from modelling of the deep bedrock system. The Forsmark site is located within the municipality of Oesthammar, about 120 km north of Stockholm. The investigated area is located along the shoreline of Oeregrundsgrepen, a funnel-shaped bay of the Baltic Sea. The area is characterized by small-scale topographic variations and is almost entirely located at altitudes lower than 20 metres above sea level. The Quaternary deposits in the area are dominated by till, characterized by a rich content of calcite which was transported by the glacier ice to the area from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. As a result, the surface waters and shallow groundwater at Forsmark are characterized by high pH values and high concentrations of certain major constituents, especially calcium and bicarbonate. The annual precipitation and runoff are 560 and 150 mm, respectively. The lakes are small and shallow, with mean and maximum depths ranging from approximately 0.1 to 1 m and 0.4 to 2 m. Sea water flows into the most low-lying lakes during events giving rise to very high sea levels. Wetlands are frequent and cover 25 to 35

Recharge and discharge of near-surface groundwater in Forsmark. Comparison of classification methods

Energy Technology Data Exchange (ETDEWEB)

Werner, Kent [Golder Associates AB, Uppsala (Sweden); Johansson, Per-Olof [Artesia Grundvattenkonsult AB, Taeby (Sweden); Brydsten, Lars [Umeaa University, Dept. of Ecology and Environmental Science (Sweden); Bosson, Emma; Berglund, Sten [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

2007-03-15

This report presents and compares data and models for identification of near-surface groundwater recharge and discharge (RD) areas in Forsmark. The general principles of groundwater recharge and discharge are demonstrated and applied to interpret hydrological and hydrogeological observations made in the Forsmark area. 'Continuous' RD classification methods considered in the study include topographical modelling, map overlays, and hydrological-hydrogeological flow modelling. 'Discrete' (point) methods include field-based and hydrochemistry-based RD classifications of groundwater monitoring well locations. The topographical RD modelling uses the digital elevation model as the only input. The map overlays use background maps of Quaternary deposits, soils, and ground- and field layers of the vegetation/land use map. Further, the hydrological-hydrogeological modelling is performed using the MIKE SHE-MIKE 11 software packages, taking into account e.g. topography, meteorology, hydrogeology, and geometry of watercourses and lakes. The best between-model agreement is found for the topography-based model and the MIKE SHE-MIKE 11 model. The agreement between the topographical model and the map overlays is less good. The agreement between the map overlays on the one hand, and the MIKE SHE and field-based RD classifications on the other, is thought to be less good, as inferred from the comparison made with the topography-based model. However, much improvement of the map overlays can likely be obtained, e.g. by using 'weights' and calibration (such exercises were outside the scope of the present study). For field-classified 'recharge wells', there is a good agreement to the hydrochemistry-based (Piper plot) well classification, but less good for the field-classified 'discharge wells'. In addition, the concentration of the age-dating parameter tritium shows low variability among recharge wells, but a large spread among discharge

A coupled regolith-lake development model applied to the Forsmark site

Energy Technology Data Exchange (ETDEWEB)

Brydsten, Lars; Stroemgren, Maarten (Umeaa Univ., Umeaa (Sweden))

2010-11-15

The Quaternary geology at the Forsmark site has been characterized using both a map of Quaternary deposits and a regolith depth model (RDM) that show the stratigraphy and thickness of different deposits. Regolith refers to all the unconsolidated deposits overlying the bedrock. The surface geology and regolith depth are important parameters for hydrogeological and geochemical modelling and for the overall understanding of the area. The safety assessment analysis should focus on processes involved during a period of 120,000 years, which includes a full glacial cycle; however, the investigations within the site description model do not cover the temporal change of the regolith, a limitation that does not fulfil the requirements for the safety assessment. To this end, this study constructs a model that can predict the surface geology, stratigraphy, and thickness of different strata at any time during a glacial cycle and applies this model to the Forsmark site. The Weichselian ice sheet covered the study area until around 9500 BC. The deglaciation revealed a marine landscape with bedrock, till and glacial clay. For the safety assessment, the most important unconsolidated strata are clay or silt: these small grains can bind nuclear elements more easily than coarser sediment particles. Thick layers of clay can be found where post-glacial clay settled on top of glacial clay, especially where the middle-aged erosion of postglacial clay is missing and where there is an uninterrupted sequence of accumulation of finegrained particles. Such areas could be found in deep marine basins that later become lakes when raised into a supra-marine position. The coupled regolith-lake development model (RLDM) predicts the course of events described above during an interglacial, especially the dynamics of the clay and silt particles. The RLDM is divided into two modules: a marine module that predicts the sediment dynamics caused by wind waves and a lake module that predicts the lake infill

A coupled regolith-lake development model applied to the Forsmark site

International Nuclear Information System (INIS)

Brydsten, Lars; Stroemgren, Maarten

2010-11-01

The Quaternary geology at the Forsmark site has been characterized using both a map of Quaternary deposits and a regolith depth model (RDM) that show the stratigraphy and thickness of different deposits. Regolith refers to all the unconsolidated deposits overlying the bedrock. The surface geology and regolith depth are important parameters for hydrogeological and geochemical modelling and for the overall understanding of the area. The safety assessment analysis should focus on processes involved during a period of 120,000 years, which includes a full glacial cycle; however, the investigations within the site description model do not cover the temporal change of the regolith, a limitation that does not fulfil the requirements for the safety assessment. To this end, this study constructs a model that can predict the surface geology, stratigraphy, and thickness of different strata at any time during a glacial cycle and applies this model to the Forsmark site. The Weichselian ice sheet covered the study area until around 9500 BC. The deglaciation revealed a marine landscape with bedrock, till and glacial clay. For the safety assessment, the most important unconsolidated strata are clay or silt: these small grains can bind nuclear elements more easily than coarser sediment particles. Thick layers of clay can be found where post-glacial clay settled on top of glacial clay, especially where the middle-aged erosion of postglacial clay is missing and where there is an uninterrupted sequence of accumulation of finegrained particles. Such areas could be found in deep marine basins that later become lakes when raised into a supra-marine position. The coupled regolith-lake development model (RLDM) predicts the course of events described above during an interglacial, especially the dynamics of the clay and silt particles. The RLDM is divided into two modules: a marine module that predicts the sediment dynamics caused by wind waves and a lake module that predicts the lake infill

Results from Marine geological investigations outside Forsmark

Energy Technology Data Exchange (ETDEWEB)

Nyberg, Johan; Elhammer, Anders; Sohlenius, Gustav; Kjellin, Bernt; Nordgren, Paer (Geological Survey of Sweden (Sweden))

2011-08-15

A detailed marine geological survey was conducted in a 10 km2 large area outside Forsmark comprising hydro acoustic, 100 m spacing between survey lines, and groundtruthing. These data, together with reanalyzed survey data retrieved in 2002 from the same area, were used to produce maps of seabed and underlying bedrock surface morphology as well as horizontal and vertical extension of sediments. An esker is discovered running approximately in a north northwesterly-south southeasterly direction in the area, which may be causing submarine groundwater discharge. Pockmarks, which are caused by sediment gas of thermogenic and/or microbial origin, are detected in the area. In addition to the original commissioned survey, bedrock surface and seabed morphology as well as horizontal and vertical extension of sediments in a larger adjacent area were reanalyzed and produced from survey lines retrieved during a commission by SKB in 2002 and during SGUs regular mapping program in 2002, 2008 and 2009

Results from Marine geological investigations outside Forsmark

International Nuclear Information System (INIS)

Nyberg, Johan; Elhammer, Anders; Sohlenius, Gustav; Kjellin, Bernt; Nordgren, Paer

2011-08-01

A detailed marine geological survey was conducted in a 10 km 2 large area outside Forsmark comprising hydro acoustic, 100 m spacing between survey lines, and groundtruthing. These data, together with reanalyzed survey data retrieved in 2002 from the same area, were used to produce maps of seabed and underlying bedrock surface morphology as well as horizontal and vertical extension of sediments. An esker is discovered running approximately in a north northwesterly-south southeasterly direction in the area, which may be causing submarine groundwater discharge. Pockmarks, which are caused by sediment gas of thermogenic and/or microbial origin, are detected in the area. In addition to the original commissioned survey, bedrock surface and seabed morphology as well as horizontal and vertical extension of sediments in a larger adjacent area were reanalyzed and produced from survey lines retrieved during a commission by SKB in 2002 and during SGUs regular mapping program in 2002, 2008 and 2009

Numerical modelling of solute transport at Forsmark with MIKE SHE. Site descriptive modelling SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Gustafsson, Lars-Goeran; Sassner, Mona (DHI Sverige AB, Stockholm (Sweden)); Bosson, Emma (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden))

2008-12-15

The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site investigations at two different locations in Sweden, referred to as the Forsmark and Laxemar areas, with the objective of siting a final repository for high-level radioactive waste. Data from the site investigations are used in a variety of modelling activities. This report presents model development and results of numerical transport modelling based on the numerical flow modelling of surface water and near-surface groundwater at the Forsmark site. The numerical modelling was performed using the modelling tool MIKE SHE and is based on the site data and conceptual model of the Forsmark areas. This report presents solute transport applications based on both particle tracking simulations and advection-dispersion calculations. The MIKE SHE model is the basis for the transport modelling presented in this report. Simulation cases relevant for the transport from a deep geological repository have been studied, but also the pattern of near surface recharge and discharge areas. When the main part of the modelling work presented in this report was carried out, the flow modelling of the Forsmark site was not finalised. Thus, the focus of this work is to describe the sensitivity to different transport parameters, and not to point out specific areas as discharge areas from a future repository (this is to be done later, within the framework of the safety assessment). In the last chapter, however, results based on simulations with the re-calibrated MIKE SHE flow model are presented. The results from the MIKE SHE water movement calculations were used by cycling the calculated transient flow field for a selected one-year period as many times as needed to achieve the desired simulation period. The solute source was located either in the bedrock or on top of the model. In total, 15 different transport simulation cases were studied. Five of the simulations were particle tracking simulations, whereas the rest

Hydrological and hydro-geological effects on wetlands and forest areas from the repository at Forsmark. Results from modelling with MIKE SHE; Hydrologiska och hydrogeologiska effekter paa vaatmarker och skogsomraaden av slutfoervarsanlaeggningen i Forsmark. Resultat fraan modellering med MIKE SHE

Energy Technology Data Exchange (ETDEWEB)

Maartensson, Erik; Gustafsson, Lars-Goeran; Gustafsson, Ann-Marie; Aneljung, Maria; Sabel, Ulrika (DHI Sverige AB, Goeteborg (Sweden))

2010-06-15

This report provides background material for investigations and associated impact assessments concerning water operations in terms of withdrawal of groundwater from the final repository for spent nuclear fuel at Forsmark. The report presents detailed modelling results in the form of supplementary sensitivity analyses and detailed hydrological and hydrogeological analyses of specific nature objects in Forsmark. The sensitivity analyses aim to investigate the sensitivity of the modelling results to i) the meteorological conditions, ii) impervious surfaces and iii) the model description of the present SFR (final repository for short-lived radioactive waste). A number of simulation cases aim to study cumulative effects of groundwater withdrawal from an extended SFR. The simulations are evaluated with respect to the groundwater table drawdown and head changes in the bedrock. The report analyses the hydrogeological and hydrological conditions for a number of selected wetland objects and forest objects. The selection of objects aims to cover different types of valuable nature objects at different geographical locations in relation to the influence area of the groundwater table drawdown. The analysis comprises groundwater levels at all nature objects, whereas wetlands with particularly high nature values have been studied in detail with respect to surface water levels, the need for water supply and object-specific water balances. These studies have been performed for different meteorological conditions in the form of a type (2006) and a statistically normal, dry and wet year, respectively, with a return period of 100 years for the dry- and wet years. All simulations for disturbed conditions with a fully open repository are done with a hydraulic conductivity of K{sub inj} = 10-7 or 10-8 m/s in the grouted zone. The results show that time-dependent precipitation and snow melt have large influence on the temporal variations of the depth to the groundwater table for

Forsmark Bedrock mapping. Stage 1 (2002) - Outcrop data including fracture data

International Nuclear Information System (INIS)

Stephens, M.B.; Bergman, T.; Andersson, J.; Hermansson, T.; Wahlgren, C.H.; Albrecht, L.; Mikko, H.

2003-02-01

Infra-red aerial photographs over the study area, taken at a height of 2700 m, were interpreted in order to locate either the position of outcrops where the bedrock is exposed at the Earth's surface or sites where the bedrock lies beneath a thin (< 50 cm) cover of Quaternary deposits. These data were critical for the planning and execution of the field activities. It was aimed to map all the outcrops in the mainland part of the study area during stage 1 of the project. These data will be integrated with both bedrock analytical data and the interpretations obtained from the study of airborne geophysical data in order to produce a bedrock map over the study area. In order to gain some information on the regional variation in the frequency and orientation of fractures over the candidate area, a documentation of the position and strike and dip of fractures longer than 100 cm was carried out at 44 outcrops. This work will also help in the selection of outcrops where detailed fracture analysis will be carried out during a later stage of the site investigation programme. Field work associated with stage 1 of the project initiated in the candidate area during June 2002. Field activities then continued in the coastal area to the northeast, in the area north of 6700000 N to the northwest of the candidate area and in the inland area to the southwest. Field activities ceased during September 2002. Both descriptive and numerical data from the 1054 observation points have been included in an outcrop database. Primarily on account of the complexity of the outcrops visited and, as a consequence, the longer time required for the field activities, a large part of the area south of road 76 was not mapped during 2002

Forsmark Bedrock mapping. Stage 1 (2002) - Outcrop data including fracture data

Energy Technology Data Exchange (ETDEWEB)

Stephens, M.B.; Bergman, T.; Andersson, J.; Hermansson, T.; Wahlgren, C.H.; Albrecht, L.; Mikko, H. [Geological Survey of Sweden, Uppsala (Sweden)

2003-02-01

Infra-red aerial photographs over the study area, taken at a height of 2700 m, were interpreted in order to locate either the position of outcrops where the bedrock is exposed at the Earth's surface or sites where the bedrock lies beneath a thin (< 50 cm) cover of Quaternary deposits. These data were critical for the planning and execution of the field activities. It was aimed to map all the outcrops in the mainland part of the study area during stage 1 of the project. These data will be integrated with both bedrock analytical data and the interpretations obtained from the study of airborne geophysical data in order to produce a bedrock map over the study area. In order to gain some information on the regional variation in the frequency and orientation of fractures over the candidate area, a documentation of the position and strike and dip of fractures longer than 100 cm was carried out at 44 outcrops. This work will also help in the selection of outcrops where detailed fracture analysis will be carried out during a later stage of the site investigation programme. Field work associated with stage 1 of the project initiated in the candidate area during June 2002. Field activities then continued in the coastal area to the northeast, in the area north of 6700000 N to the northwest of the candidate area and in the inland area to the southwest. Field activities ceased during September 2002. Both descriptive and numerical data from the 1054 observation points have been included in an outcrop database. Primarily on account of the complexity of the outcrops visited and, as a consequence, the longer time required for the field activities, a large part of the area south of road 76 was not mapped during 2002.

Geology - Background complementary studies. Forsmark modelling stage 2.2

Energy Technology Data Exchange (ETDEWEB)

Stephens, Michael B. [Geological Survey of Sweden, Uppsala (Sweden); Skagius, Kristina [Kemakta Konsult AB, Stockholm (Sweden)] (eds.)

2007-09-15

borehole (VSP) reflection seismic data along profiles 2 and 5, Forsmark, Sweden. Christopher Juhlin. 3. Correlation of 2D surface seismic, vertical seismic profile (VSP), and geological and sonic data in boreholes KFM01A and KFM02A, Forsmark: Background analysis. Nicoleta Enescu and Calin Cosma. 4. Refraction seismic data and bedrock velocity distribution at Forsmark. Johan Nissen. 5. Correlation between refraction seismic data, low magnetic lineaments and deformation zones (model stage 2.2). Hans Isaksson. 6. Interpretation of tomography inversion models for seismic refraction data along profile LFM001017 in Forsmark. Haakan Mattsson. 7. Correlation of oriented radar reflectors with geological features in boreholes at Forsmark. Seje Carlsten.

Geology - Background complementary studies. Forsmark modelling stage 2.2

International Nuclear Information System (INIS)

Stephens, Michael B.; Skagius, Kristina

2007-09-01

borehole (VSP) reflection seismic data along profiles 2 and 5, Forsmark, Sweden. Christopher Juhlin. 3. Correlation of 2D surface seismic, vertical seismic profile (VSP), and geological and sonic data in boreholes KFM01A and KFM02A, Forsmark: Background analysis. Nicoleta Enescu and Calin Cosma. 4. Refraction seismic data and bedrock velocity distribution at Forsmark. Johan Nissen. 5. Correlation between refraction seismic data, low magnetic lineaments and deformation zones (model stage 2.2). Hans Isaksson. 6. Interpretation of tomography inversion models for seismic refraction data along profile LFM001017 in Forsmark. Haakan Mattsson. 7. Correlation of oriented radar reflectors with geological features in boreholes at Forsmark. Seje Carlsten

Numerical modelling of solute transport at Forsmark with MIKE SHE. Site descriptive modelling SDM-Site Forsmark

International Nuclear Information System (INIS)

Gustafsson, Lars-Goeran; Sassner, Mona; Bosson, Emma

2008-12-01

The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site investigations at two different locations in Sweden, referred to as the Forsmark and Laxemar areas, with the objective of siting a final repository for high-level radioactive waste. Data from the site investigations are used in a variety of modelling activities. This report presents model development and results of numerical transport modelling based on the numerical flow modelling of surface water and near-surface groundwater at the Forsmark site. The numerical modelling was performed using the modelling tool MIKE SHE and is based on the site data and conceptual model of the Forsmark areas. This report presents solute transport applications based on both particle tracking simulations and advection-dispersion calculations. The MIKE SHE model is the basis for the transport modelling presented in this report. Simulation cases relevant for the transport from a deep geological repository have been studied, but also the pattern of near surface recharge and discharge areas. When the main part of the modelling work presented in this report was carried out, the flow modelling of the Forsmark site was not finalised. Thus, the focus of this work is to describe the sensitivity to different transport parameters, and not to point out specific areas as discharge areas from a future repository (this is to be done later, within the framework of the safety assessment). In the last chapter, however, results based on simulations with the re-calibrated MIKE SHE flow model are presented. The results from the MIKE SHE water movement calculations were used by cycling the calculated transient flow field for a selected one-year period as many times as needed to achieve the desired simulation period. The solute source was located either in the bedrock or on top of the model. In total, 15 different transport simulation cases were studied. Five of the simulations were particle tracking simulations, whereas the rest

District heating from Forsmark

International Nuclear Information System (INIS)

1980-11-01

The district heating system of Greater Stockholm must be based on other energy sources than oil. Two alternatives are assessed, namely heat from Forsmark or a coal fueled plant in the region of Stockholm. Forsmark 3 can produce both electricity and heat from the year 1988 on. The capacity can be increased by coal fueled blocks. For low electricity use, 115 TWh in the year 1990, the Forsmark alternative will be profitable. The alternative will be profitable. The alternative with a fossile fuelled plant will be profitable when planning for high consumption of electricity, 125 TWh. The Forsmark alternative means high investments and the introduction of new techniques. (G.B.)

Hydrogeological structure model of the Olkiluoto Site. Update in 2010

International Nuclear Information System (INIS)

Vaittinen, T.; Ahokas, H.; Nummela, J.; Paulamaeki, S.

2011-09-01

As part of the programme for the final disposal of spent nuclear fuel, a hydrogeological structure model containing the hydraulically significant zones on Olkiluoto Island has been compiled. The structure model describes the deterministic site scale zones that dominate the groundwater flow. The main objective of the study is to provide the geometry and the hydrogeological properties related to the groundwater flow for the zones and the sparsely fractured bedrock to be used in the numerical modelling of groundwater flow and geochemical transport and thereby in the safety assessment. Also, these zones should be taken into account in the repository layout and in the construction of the disposal facility and they have a long-term impact on the evolution of the site and the safety of the disposal repository. The previous hydrogeological model was compiled in 2008 and this updated version is based on data available at the end of May 2010. The updating was based on new hydrogeological observations and a systematic approach covering all drillholes to assess measured fracture transmissivities typical of the site-scale hydrogeological zones. New data consisted of head observations and interpreted pressure and flow responses caused by field activities. Essential background data for the modelling included the ductile deformation model and the site scale brittle deformation zones modelled in the geological model version 2.0. The GSM combine both geological and geophysical investigation data on the site. As a result of the modelling campaign, hydrogeological zones HZ001, HZ008, HZ19A, HZ19B, HZ19C, HZ20A, HZ20B, HZ21, HZ21B, HZ039, HZ099, OL-BFZ100, and HZ146 were included in the structure model. Compared with the previous model, zone HZ004 was replaced with zone HZ146 and zone HZ039 was introduced for the first time. Alternative zone HZ21B was included in the basic model. For the modelled zones, both the zone intersections, describing the fractures with dominating groundwater

Hydrochemistry in surface water and shallow groundwater. Site descriptive modelling SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Troejbom, Mats (Mopelikan, Norrtaelje (SE)); Soederbaeck, Bjoern (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Johansson, Per-Olof (Artesia Grundvattenkonsult AB, Taeby (SE))

2007-10-15

With a mathematical/statistical approach, a large number of visualisations and models reflect the hydrochemistry in the Forsmark area, with the intention to give an understanding of important processes and factors that affect the hydrochemistry in the surface systems. In order to widen the perspective, all data from the Forsmark 2.2 stage including observations from different levels of the bedrock, as well as hydrological measurements and characterisations of the Quaternary deposits, have been included in the analyses. The purpose of this report is to give a general understanding of the site and to explain observed overall patterns as well as anomalies, and, ultimately, to present a conceptual model that explains the present hydrochemistry in the surface system in the light of the past. The report may also function as a basis for further evaluation and testing of scenarios, and may be regarded as an intermediate step between raw data compilations from the vast SICADA database and specialised expert models. The flat topography and the recent withdrawal of the Baltic Sea due to the isostatic land-uplift are two important factors determining the hydrochemistry in the Forsmark area. Marine remnants in the Quaternary deposits, as well as modern sea water intrusions, are therefore strongly influencing the hydrochemistry, especially in areas at low altitude close to the coast. Large-scale marine gradients in the surface system are consistent with the conceptual model that describes the hydrochemical evolution in a paleo-hydrologic perspective. The Forsmark area is covered by glacial remnants, mostly in the form of a till layer, which was deposited during the Weichselian glaciation and deglaciation. When the ice cover retreated about 11,000 years ago, these deposits were exposed on the sea floor. This till layer is characterized by a rich content of calcite, originating from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. The dissolution of this

Hydrochemistry in surface water and shallow groundwater. Site descriptive modelling SDM-Site Forsmark

International Nuclear Information System (INIS)

Troejbom, Mats; Soederbaeck, Bjoern; Johansson, Per-Olof

2007-10-01

With a mathematical/statistical approach, a large number of visualisations and models reflect the hydrochemistry in the Forsmark area, with the intention to give an understanding of important processes and factors that affect the hydrochemistry in the surface systems. In order to widen the perspective, all data from the Forsmark 2.2 stage including observations from different levels of the bedrock, as well as hydrological measurements and characterisations of the Quaternary deposits, have been included in the analyses. The purpose of this report is to give a general understanding of the site and to explain observed overall patterns as well as anomalies, and, ultimately, to present a conceptual model that explains the present hydrochemistry in the surface system in the light of the past. The report may also function as a basis for further evaluation and testing of scenarios, and may be regarded as an intermediate step between raw data compilations from the vast SICADA database and specialised expert models. The flat topography and the recent withdrawal of the Baltic Sea due to the isostatic land-uplift are two important factors determining the hydrochemistry in the Forsmark area. Marine remnants in the Quaternary deposits, as well as modern sea water intrusions, are therefore strongly influencing the hydrochemistry, especially in areas at low altitude close to the coast. Large-scale marine gradients in the surface system are consistent with the conceptual model that describes the hydrochemical evolution in a paleo-hydrologic perspective. The Forsmark area is covered by glacial remnants, mostly in the form of a till layer, which was deposited during the Weichselian glaciation and deglaciation. When the ice cover retreated about 11,000 years ago, these deposits were exposed on the sea floor. This till layer is characterized by a rich content of calcite, originating from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. The dissolution of this

Soils and site types in the Forsmark area

International Nuclear Information System (INIS)

Lundin, Lars; Lode, Elve; Stendahl, Johan; Melkerud, Per-Arne; Bjoerkvald, Louise; Thorstensson, Anna

2004-01-01

Investigations to give prerequisites for long-term storage of nuclear waste are made by the Swedish Nuclear Fuel and Waste Management Company (SKB AB). Ecosystem functions are crucial in this management. The range of the scope is wide including bedrock, regolith, hydrosphere and biosphere. The interface between deep geological formations and surface systems is then considered very important. This would be the top of the regolith, where soils are developed. Special attention has been paid to these layers with fairly comprehensive investigations. Field investigations were made for one of the candidate areas, the Forsmark area, in 2002 by the Department of Forest Soils, Swedish University of Agricultural Sciences. In these ecosystem functions, the upper part of the regolith is one crucial component and the focus in the investigations was on the upper metre of the soil. Variables determined include vegetation, hydrology, soil parent material, textural composition, soil type and physical and chemical properties of relevant soil layers. Methods used in the investigation coincide with those of the Swedish Forest Soil Inventory, which provide possibilities to compare properties in the Forsmark area with those of total Sweden and regions of the country. Soil properties were determined thoroughly on eight site types in two replicates to provide statistical significance. However, this meant that the investigation did not have a total spatial coverage. Instead, the spatial distribution of soils in the area was determined from a GIS based on the inventory made and information on vegetation types, distribution of Quaternary deposits and a hydrological index. From this GIS, distributions were compared with other parts of the country. The geographical location of the Forsmark area (N 60 deg 22 min; E 18 deg 13 min) is on the northeast coast of central Sweden bordering to the Bothnian Sea. The area is low-lying, reaching only up to 15 m above the sea, which means that the soils are

Hydrogeological and geochemical investigations of elevated arsenic (As) abundances in groundwater in Ireland

International Nuclear Information System (INIS)

Gilligan, M.; Feely, M.; Morrison, L.; Henry, T.; Higgins, T.M.; Zhang, C.

2009-01-01

Full text: This study will use hydrogeology, geochemistry and chemical speciation studies to investigate the presence of elevated arsenic (As) abundances in groundwater in Ireland. Comparative studies of groundwater, bedrock and mineral chemistry will be linked to hydrogeology, GIS and statistical studies. This approach will facilitate characterization of the temporal and spatial distribution of As as a function of groundwater and bedrock geology using the pressures, pathways and receptors approach. Arsenic speciation studies will determine As toxicity, bioavailability and potential for migration in this environment thus addressing human health issues. (author)

Forsmark site investigation. Investigation of marine and lacustrine sediment in lakes. Field data 2003

Energy Technology Data Exchange (ETDEWEB)

Hedenstroem, Anna [SGU, Uppsala (Sweden)

2003-04-01

The aim of this activity is to describe the aerial and stratigraphical distribution of marine and lacustrine sediment i.e. sediment overlaying the glacial till and/or bedrock surface, in lakes in the Forsmark area. The investigation is carried out within areas where mapping of unconsolidated Quaternary deposits is presently carried out. Since small and shallow lakes cover a large part of the region, this work will give important information on the distribution and stratigraphy of sedimentary deposits not included in the regular mapping of unconsolidated Quaternary deposits within the site investigation programme. Samples were also collected for laboratory analyses of grain size distribution, mineralogical composition as well as the total content of C, N and S and calcium carbonate. The analyses will be carried out on selected samples of representative sedimentary units in order to characterise the chemical and physical properties of the unconsolidated deposits. The analytical data will be useful for the hydrogeological modelling and for models of the Quaternary evolution of the area. The mineralogical analyses of clay may provide information on the origin of the clay particles. One stratigraphic sequence from Lake Eckarfjaerden will be stored for later analyses, e.g. pollen analysis. This report includes field data from spring 2003. Together, the field data and the forthcoming results from the laboratory analyses will form the basis for construction of stratigraphical profiles to be presented in a following report in the fall 2003.

Forsmark site investigation. Investigation of marine and lacustrine sediment in lakes. Field data 2003

International Nuclear Information System (INIS)

Hedenstroem, Anna

2003-04-01

The aim of this activity is to describe the aerial and stratigraphical distribution of marine and lacustrine sediment i.e. sediment overlaying the glacial till and/or bedrock surface, in lakes in the Forsmark area. The investigation is carried out within areas where mapping of unconsolidated Quaternary deposits is presently carried out. Since small and shallow lakes cover a large part of the region, this work will give important information on the distribution and stratigraphy of sedimentary deposits not included in the regular mapping of unconsolidated Quaternary deposits within the site investigation programme. Samples were also collected for laboratory analyses of grain size distribution, mineralogical composition as well as the total content of C, N and S and calcium carbonate. The analyses will be carried out on selected samples of representative sedimentary units in order to characterise the chemical and physical properties of the unconsolidated deposits. The analytical data will be useful for the hydrogeological modelling and for models of the Quaternary evolution of the area. The mineralogical analyses of clay may provide information on the origin of the clay particles. One stratigraphic sequence from Lake Eckarfjaerden will be stored for later analyses, e.g. pollen analysis. This report includes field data from spring 2003. Together, the field data and the forthcoming results from the laboratory analyses will form the basis for construction of stratigraphical profiles to be presented in a following report in the fall 2003

Groundwater flow modelling of periods with periglacial and glacial climate conditions - Forsmark

International Nuclear Information System (INIS)

Vidstrand, Patrik; Follin, Sven; Zugec, Nada

2010-12-01

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The groundwater flow modelling study reported here comprises a coupled thermal-hydraulic-chemical (T-H-C) analysis of periods with periglacial and glacial climate conditions. Hydraulic-mechanical (H-M) issues are also handled but no coupled flow modelling is done. The objective of the report is to provide bounding hydrogeological estimates at different stages during glaciation and deglaciation of a glacial cycle for subsequent use in safety assessment applications within SKB's project SR-Site. Three cases with different climate conditions are analysed here: (i) Temperate case, (ii) Glacial case without permafrost, and (iii) Glacial case with permafrost. The glacial periods are transient and encompass approximately 19,000 years. The simulation results comprise residual fluid pressures, Darcy fluxes, and water salinities, as well as advective transport performance measures obtained by particle tracking such as flow path lengths, travel times and flow-related transport resistances. The modelling is accompanied by a sensitivity study that addresses the impact of the following matters: the direction of the ice sheet advance, the speed of the ice sheet margin, the bedrock hydraulic and transport properties, the temperature at the ice-subsurface interface close to the ice sheet margin, and the initial hydrochemical conditions

Groundwater flow modelling of periods with periglacial and glacial climate conditions - Forsmark

Energy Technology Data Exchange (ETDEWEB)

Vidstrand, Patrik (TerraSolve AB, Floda (Sweden)); Follin, Sven (SF GeoLogic AB, Taeby (Sweden)); Zugec, Nada (Bergab, Stockholm (Sweden))

2010-12-15

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The groundwater flow modelling study reported here comprises a coupled thermal-hydraulic-chemical (T-H-C) analysis of periods with periglacial and glacial climate conditions. Hydraulic-mechanical (H-M) issues are also handled but no coupled flow modelling is done. The objective of the report is to provide bounding hydrogeological estimates at different stages during glaciation and deglaciation of a glacial cycle for subsequent use in safety assessment applications within SKB's project SR-Site. Three cases with different climate conditions are analysed here: (i) Temperate case, (ii) Glacial case without permafrost, and (iii) Glacial case with permafrost. The glacial periods are transient and encompass approximately 19,000 years. The simulation results comprise residual fluid pressures, Darcy fluxes, and water salinities, as well as advective transport performance measures obtained by particle tracking such as flow path lengths, travel times and flow-related transport resistances. The modelling is accompanied by a sensitivity study that addresses the impact of the following matters: the direction of the ice sheet advance, the speed of the ice sheet margin, the bedrock hydraulic and transport properties, the temperature at the ice-subsurface interface close to the ice sheet margin, and the initial hydrochemical conditions.

Modelling of present and future hydrology and solute transport at Forsmark. SR-Site Biosphere

Energy Technology Data Exchange (ETDEWEB)

Bosson, Emma (Swedish Nuclear Fuel and Waste Management Co., Stocholm (Sweden)); Sassner, Mona; Sabel, Ulrika; Gustafsson, Lars-Goeran (DHI Sverige AB (Sweden))

2010-10-15

the south-eastern part. Till is the dominating type of QD. The QD are often shallow; the mean depth is approximately 5 m and the maximum depth observed on land is 16 m. Most of the lakes are underlain by fine-grained sediments. Bedrock outcrops are frequent but constitute only 5% of the area. Granitic rock is dominating bedrock of the area. The main changes between the SDM-Site MIKE SHE model and the present SR-Site MIKE SHE model are the size of the model area and the grid resolution, which both are larger in the SR-Site version, and the updated description of the geometry and hydraulic properties of the bedrock. Also, the uppermost part of the QD-profile has been taken into consideration when describing the hydraulic properties in the unsaturated zone compartment of the MIKE SHE model. In previous model versions the distribution of the QD has been the same in both the saturated and unsaturated zone description. In the present version the information from the QD-mapping regarding the upper 0.5 m has been included in the description of the unsaturated zone. The hydrology under different future conditions with regard to shoreline positions and climate conditions has been simulated. Three different shorelines were studied, corresponding to 2000 AD, 5000 AD and 10,000 AD, and three different climates, temperate (i.e. the present climate), wet (i.e. temperate with increased precipitation), and periglacial (cold climate with permafrost). No full-scale sensitivity analysis of the different model parameters was carried out, but a quality check and calibration of the model was made by comparing model results to measured data. Based on the calibrated model describing present conditions at the Forsmark site the different cases were defined for simulating future shorelines and climates. A simulation case describing present conditions, i.e. the present climate and the 2000 AD shoreline, was compared to measured data from the site. To obtain an acceptable response when modelling a

Modelling of present and future hydrology and solute transport at Forsmark. SR-Site Biosphere

International Nuclear Information System (INIS)

Bosson, Emma; Sassner, Mona; Sabel, Ulrika; Gustafsson, Lars-Goeran

2010-10-01

the south-eastern part. Till is the dominating type of QD. The QD are often shallow; the mean depth is approximately 5 m and the maximum depth observed on land is 16 m. Most of the lakes are underlain by fine-grained sediments. Bedrock outcrops are frequent but constitute only 5% of the area. Granitic rock is dominating bedrock of the area. The main changes between the SDM-Site MIKE SHE model and the present SR-Site MIKE SHE model are the size of the model area and the grid resolution, which both are larger in the SR-Site version, and the updated description of the geometry and hydraulic properties of the bedrock. Also, the uppermost part of the QD-profile has been taken into consideration when describing the hydraulic properties in the unsaturated zone compartment of the MIKE SHE model. In previous model versions the distribution of the QD has been the same in both the saturated and unsaturated zone description. In the present version the information from the QD-mapping regarding the upper 0.5 m has been included in the description of the unsaturated zone. The hydrology under different future conditions with regard to shoreline positions and climate conditions has been simulated. Three different shorelines were studied, corresponding to 2000 AD, 5000 AD and 10,000 AD, and three different climates, temperate (i.e. the present climate), wet (i.e. temperate with increased precipitation), and periglacial (cold climate with permafrost). No full-scale sensitivity analysis of the different model parameters was carried out, but a quality check and calibration of the model was made by comparing model results to measured data. Based on the calibrated model describing present conditions at the Forsmark site the different cases were defined for simulating future shorelines and climates. A simulation case describing present conditions, i.e. the present climate and the 2000 AD shoreline, was compared to measured data from the site. To obtain an acceptable response when modelling a

Work at Forsmark since ASSET 1996

Energy Technology Data Exchange (ETDEWEB)

Loewenhielm, G; Andersson, O [Forsmark Kraftgrupp AB, Oesthammar (Sweden)

1997-10-01

The following directions of work at Forsmark since ASSET 1996 are briefly described: peer review follow-up; work related to peer review, Forsmark 2 mini-ASSET; MTO(man-technology-organization)-analysis method, concept development, combination of MTO and ASSET methods; Forsmark INES manual.

Radon as a groundwater tracer in Forsmark and Laxemar

Energy Technology Data Exchange (ETDEWEB)

Grolander, Sara

2009-10-15

Radon concentrations were measured in different water types in Forsmark and Laxemar during the site investigation and within this study. From these measurements it can be concluded that large differences between surface water, near surface groundwater and deep groundwater can be found in both Laxemar and Forsmark. The differences in radon concentrations between different water types are used in this study to detect interactions between surface water, near surface water and deep groundwater. From the radon measurements it can also be concluded that radon concentration in deep groundwater varies largely with depth. These variations with depth are probably caused by groundwater flow in conductive fracture zones in the bedrock. The focus of this study has been the radon concentration of near surface groundwater and the interaction between near surface groundwater and deep groundwater. Radon measurements have been done using the RAD-7 radon detector within this study. It could be concluded that RAD-7 is a good technique for radon measurements and also easy to use in field. The radon concentrations measured in near surface groundwater in Laxemar within this study were low and homogenous. The variation in radon concentration has been analyses and compared to other parameters. Since the hypothesis of this study has been that there are differences in radon concentrations between recharging and discharging groundwater, the most important parameter to consider is the recharge/discharge field classification of the wells. No correlation between the recharge/discharge classifications of wells and the radon concentrations were found. The lack of correlation between groundwater flow patterns and radon concentration means that it is not possible to detect flow patterns in near surface groundwater using radon as a tracer in the Laxemar area. The lack of correlation can be caused by the fact that there are just a few wells located in areas classified as recharge area. It can also be

Description of surface systems. Preliminary site description. Forsmark area Version 1.2

Energy Technology Data Exchange (ETDEWEB)

Lindborg, Tobias [ed.

2005-06-01

Swedish Nuclear Fuel and Waste Management Co (SKB) started site investigations for a deep repository for spent nuclear fuel in 2002 at two different sites in Sweden, Forsmark and Oskarshamn. The investigations should provide necessary information for a license application aimed at starting underground exploration. For this reason, ecosystem data need to be interpreted and assessed into site descriptive models, which in turn are used for safety assessment studies and for environmental impact assessment. Descriptions of the surface system are also needed for further planning of the site investigations. This report describes the surface ecosystems of the Forsmark site (e.g. hydrology, Quaternary deposits, chemistry, vegetation, animals and the human land use). The ecosystem description is an integration of the site and its regional setting, covering the current state of the biosphere as well as the ongoing natural processes affecting the longterm development. Improving the descriptions is important during both the initial and the complete site investigation phase. Before starting of the initial phase in Forsmark, version 0 of the site descriptive model was developed. The results of the initial site investigation phase is compiled into a preliminary site description of Forsmark (version 1.2) in June 2005. This report provides the major input and background to the biosphere description, in the 1.2 version of the Forsmark site description. The basis for this interim version is quality-assured field data from the Forsmark sub area and regional area, available in the SKB SICADA, and GIS data bases as of July 31th 2004 as well as version 1.1 of the Site Descriptive Model. To achieve an ecosystem site description there is a need to develop discipline-specific models by interpreting and analysing primary data. The different discipline-specific models are then integrated into a system describing interactions and flows and stocks of matter between and within functional units in

Description of surface systems. Preliminary site description. Forsmark area Version 1.2

International Nuclear Information System (INIS)

Lindborg, Tobias

2005-06-01

Swedish Nuclear Fuel and Waste Management Co (SKB) started site investigations for a deep repository for spent nuclear fuel in 2002 at two different sites in Sweden, Forsmark and Oskarshamn. The investigations should provide necessary information for a license application aimed at starting underground exploration. For this reason, ecosystem data need to be interpreted and assessed into site descriptive models, which in turn are used for safety assessment studies and for environmental impact assessment. Descriptions of the surface system are also needed for further planning of the site investigations. This report describes the surface ecosystems of the Forsmark site (e.g. hydrology, Quaternary deposits, chemistry, vegetation, animals and the human land use). The ecosystem description is an integration of the site and its regional setting, covering the current state of the biosphere as well as the ongoing natural processes affecting the longterm development. Improving the descriptions is important during both the initial and the complete site investigation phase. Before starting of the initial phase in Forsmark, version 0 of the site descriptive model was developed. The results of the initial site investigation phase is compiled into a preliminary site description of Forsmark (version 1.2) in June 2005. This report provides the major input and background to the biosphere description, in the 1.2 version of the Forsmark site description. The basis for this interim version is quality-assured field data from the Forsmark sub area and regional area, available in the SKB SICADA, and GIS data bases as of July 31th 2004 as well as version 1.1 of the Site Descriptive Model. To achieve an ecosystem site description there is a need to develop discipline-specific models by interpreting and analysing primary data. The different discipline-specific models are then integrated into a system describing interactions and flows and stocks of matter between and within functional units in

Hydrogeology of the Owego-Apalachin Elementary School Geothermal Fields, Tioga County, New York

Science.gov (United States)

Williams, John H.; Kappel, William M.

2015-12-22

The hydrogeology of the Owego-Apalachin Elementary School geothermal fields, which penetrate saline water and methane in fractured upper Devonian age bedrock in the Owego Creek valley, south-central New York, was characterized through the analysis of drilling and geophysical logs, water-level monitoring data, and specific-depth water samples. Hydrogeologic insights gained during the study proved beneficial for the design of the geothermal drilling program and protection of the overlying aquifer during construction, and may be useful for the development of future geothermal fields and other energy-related activities, such as drilling for oil and natural gas in similar fractured-bedrock settings.

Monitoring Forsmark. Moose age composition, reproduction and antler development in Forsmark; Monitoring Forsmark. Aelgstammens aalderssammansaettning reproduktion och hornutveckling i Forsmark

Energy Technology Data Exchange (ETDEWEB)

Cederlund, Goeran; Broman, Emil (Svensk Naturfoervaltning AB (Sweden))

2011-05-15

The moose (Alces alces) is an important game species in Forsmark, as well as in Sweden in general. Hunting on moose is subject to strict local regulations and restrictions within a management program. Such restrictions will have considerable effects on demography. This has led to a moose population in Forsmark with biased sex ratio with fewer adult males than females and a generally low average age. High hunting pressure on males has caused a low survival rate and the chance to survive more than five years is just a few percent. Restrictions in hunting pressure on females have caused a generally higher survival rate and a higher average age compared to males. Sex differences in body mass are normal compared to other populations in southern Sweden. Mean body mass of culled calves is an important measure of quality of the population, since it reflects the available food resources in the management area. Body mass among calves in Forsmark is generally low, indicating a deteriorated food resource due to either ambient population density and/or hampered food production in the forest. The average reproduction rate is normal compared to other populations in this part of Sweden. However, one year old females (yearlings) have a fairly low production of eggs per female (ovulation rate). As the yearlings constitute a considerable part of the population in Forsmark, their lowered ovulation rate will affect the rate of recruitment of calves to the local population. The moose population seems to have been subject to considerable variation in density during the last decade, which is probably a joint effect of changes in demography (hunting), changes in food resources due to forestry management and by food competition from other browsers in the area. Local managers believe that the population has reached such a low level (although not verified by surveys) that the number of moose has to be increased. It is vital to stress the importance of keeping up collection of data from the

Encapsulation plant at Forsmark

International Nuclear Information System (INIS)

Nystroem, Anders

2007-08-01

SKB has already carried out a preliminary study of an encapsulation plant detached from Clab (Central interim storage for spent fuels). This stand-alone encapsulation plant was named FRINK and its assumed siting was the above-ground portion of the final repository, irrespective of the repository's location. The report previously presented was produced in cooperation with BNFL Engineering Ltd in Manchester and the fuel reception technical solution was examined by Gesellschaft fuer Nuklear-Service mbH (GNS) in Hannover and by Societe Generale pour les Techniques Nouvelles (SGN) in Paris. This report is an update of the earlier preliminary study report and is based on the assumption that the encapsulation plant and also the final repository will be sited in the Forsmark area. SKB's main alternative for siting the encapsulation plant is next to Clab. Planning of this facility is ongoing and technical solutions from the planning work have been incorporated in this report. An encapsulation plant placed in proximity to any final repository in Forsmark forms part of the alternative presentation in the application for permission to construct and operate an installation at Clab. The main technical difference between the planned encapsulation plant at Clab and an encapsulation plant at a final repository at Forsmark is how the fuel is managed and prepared before actual encapsulation. Fuel reception at the encapsulation plant in Forsmark would be dry, i.e. there would be no water-filled pools at the facility. Clab is used for verificatory fuel measurements, sorting and drying of the fuel before transport to Forsmark. This means that Clab will require a measure of rebuilding and supplementary equipment. In purely technical terms, the prospects for building an encapsulation plant sited at Forsmark are good. A description of the advantages and drawbacks of siting the encapsulation plant at Clab as opposed to any final repository at Forsmark is presented in a separate report

Encapsulation plant at Forsmark

Energy Technology Data Exchange (ETDEWEB)

Nystroem, Anders

2007-08-15

SKB has already carried out a preliminary study of an encapsulation plant detached from Clab (Central interim storage for spent fuels). This stand-alone encapsulation plant was named FRINK and its assumed siting was the above-ground portion of the final repository, irrespective of the repository's location. The report previously presented was produced in cooperation with BNFL Engineering Ltd in Manchester and the fuel reception technical solution was examined by Gesellschaft fuer Nuklear-Service mbH (GNS) in Hannover and by Societe Generale pour les Techniques Nouvelles (SGN) in Paris. This report is an update of the earlier preliminary study report and is based on the assumption that the encapsulation plant and also the final repository will be sited in the Forsmark area. SKB's main alternative for siting the encapsulation plant is next to Clab. Planning of this facility is ongoing and technical solutions from the planning work have been incorporated in this report. An encapsulation plant placed in proximity to any final repository in Forsmark forms part of the alternative presentation in the application for permission to construct and operate an installation at Clab. The main technical difference between the planned encapsulation plant at Clab and an encapsulation plant at a final repository at Forsmark is how the fuel is managed and prepared before actual encapsulation. Fuel reception at the encapsulation plant in Forsmark would be dry, i.e. there would be no water-filled pools at the facility. Clab is used for verificatory fuel measurements, sorting and drying of the fuel before transport to Forsmark. This means that Clab will require a measure of rebuilding and supplementary equipment. In purely technical terms, the prospects for building an encapsulation plant sited at Forsmark are good. A description of the advantages and drawbacks of siting the encapsulation plant at Clab as opposed to any final repository at Forsmark is presented in a separate

Bedrock geology Forsmark. Modelling stage 2.3. Implications for and verification of the deterministic geological models based on complementary data

Energy Technology Data Exchange (ETDEWEB)

Stephens, Michael B. (Geological Survey of Sweden, Uppsala (Sweden)); Simeonov, Assen (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Isaksson, Hans (GeoVista AB, Luleaa (Sweden))

2008-12-15

The Swedish Nuclear Fuel and Waste Management Company is in the process of completing site descriptive modelling at two locations in Sweden, with the objective to site a deep geological repository for spent nuclear fuel. At Forsmark, the results of the stage 2.2 geological modelling formed the input for downstream users. Since complementary ground and borehole geological and geophysical data, acquired after model stage 2.2, were not planned to be included in the deterministic rock domain, fracture domain and deformation zone models supplied to the users, it was deemed necessary to evaluate the implications of these stage 2.3 data for the stage 2.2 deterministic geological models and, if possible, to make use of these data to verify the models. This report presents the results of the analysis of the complementary stage 2.3 geological and geophysical data. Model verification from borehole data has been implemented in the form of a prediction-outcome test. The stage 2.3 geological and geophysical data at Forsmark mostly provide information on the bedrock outside the target volume. Additional high-resolution ground magnetic data and the data from the boreholes KFM02B, KFM11A, KFM12A and HFM33 to HFM37 can be included in this category. Other data complement older information of identical character, both inside and outside this volume. These include the character and kinematics of deformation zones and fracture mineralogy. In general terms, it can be stated that all these new data either confirm the geological modelling work completed during stage 2.2 or are in good agreement with the data that were used in this work. In particular, although the new high-resolution ground magnetic data modify slightly the position and trace length of some stage 2.2 deformation zones at the ground surface, no new or modified deformation zones with a trace length longer than 3,000 m at the ground surface have emerged. It is also apparent that the revision of fracture orientation data

Bedrock geology Forsmark. Modelling stage 2.3. Implications for and verification of the deterministic geological models based on complementary data

International Nuclear Information System (INIS)

Stephens, Michael B.; Simeonov, Assen; Isaksson, Hans

2008-12-01

The Swedish Nuclear Fuel and Waste Management Company is in the process of completing site descriptive modelling at two locations in Sweden, with the objective to site a deep geological repository for spent nuclear fuel. At Forsmark, the results of the stage 2.2 geological modelling formed the input for downstream users. Since complementary ground and borehole geological and geophysical data, acquired after model stage 2.2, were not planned to be included in the deterministic rock domain, fracture domain and deformation zone models supplied to the users, it was deemed necessary to evaluate the implications of these stage 2.3 data for the stage 2.2 deterministic geological models and, if possible, to make use of these data to verify the models. This report presents the results of the analysis of the complementary stage 2.3 geological and geophysical data. Model verification from borehole data has been implemented in the form of a prediction-outcome test. The stage 2.3 geological and geophysical data at Forsmark mostly provide information on the bedrock outside the target volume. Additional high-resolution ground magnetic data and the data from the boreholes KFM02B, KFM11A, KFM12A and HFM33 to HFM37 can be included in this category. Other data complement older information of identical character, both inside and outside this volume. These include the character and kinematics of deformation zones and fracture mineralogy. In general terms, it can be stated that all these new data either confirm the geological modelling work completed during stage 2.2 or are in good agreement with the data that were used in this work. In particular, although the new high-resolution ground magnetic data modify slightly the position and trace length of some stage 2.2 deformation zones at the ground surface, no new or modified deformation zones with a trace length longer than 3,000 m at the ground surface have emerged. It is also apparent that the revision of fracture orientation data

Soils and site types in the Forsmark area

Energy Technology Data Exchange (ETDEWEB)

Lundin, Lars; Lode, Elve; Stendahl, Johan; Melkerud, Per-Arne; Bjoerkvald, Louise; Thorstensson, Anna [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Soils

2004-01-01

Investigations to give prerequisites for long-term storage of nuclear waste are made by the Swedish Nuclear Fuel and Waste Management Company (SKB AB). Ecosystem functions are crucial in this management. The range of the scope is wide including bedrock, regolith, hydrosphere and biosphere. The interface between deep geological formations and surface systems is then considered very important. This would be the top of the regolith, where soils are developed. Special attention has been paid to these layers with fairly comprehensive investigations. Field investigations were made for one of the candidate areas, the Forsmark area, in 2002 by the Department of Forest Soils, Swedish University of Agricultural Sciences. In these ecosystem functions, the upper part of the regolith is one crucial component and the focus in the investigations was on the upper metre of the soil. Variables determined include vegetation, hydrology, soil parent material, textural composition, soil type and physical and chemical properties of relevant soil layers. Methods used in the investigation coincide with those of the Swedish Forest Soil Inventory, which provide possibilities to compare properties in the Forsmark area with those of total Sweden and regions of the country. Soil properties were determined thoroughly on eight site types in two replicates to provide statistical significance. However, this meant that the investigation did not have a total spatial coverage. Instead, the spatial distribution of soils in the area was determined from a GIS based on the inventory made and information on vegetation types, distribution of Quaternary deposits and a hydrological index. From this GIS, distributions were compared with other parts of the country. The geographical location of the Forsmark area (N 60 deg 22 min; E 18 deg 13 min) is on the northeast coast of central Sweden bordering to the Bothnian Sea. The area is low-lying, reaching only up to 15 m above the sea, which means that the soils are

Modelling of soil depth and lake sediments. An application of the GeoEditor at the Forsmark site

International Nuclear Information System (INIS)

Vikstroem, Maria

2005-02-01

This report aims at describing the modelled soil depth according to three layers with different hydrogeological properties at the Forsmark site, based on available data from boreholes, observation points, seismic data and radar profiles. For the lakes in the area, the sediment has been modelled according to six layers of the most common deposits in the area. The peat layer at Stenroesmossen has also been visualized. The program used in the modelling of soil depths is the GeoEditor, which is an ArcView3.3-extension. The input data used in the model consist of 1,532 points based on seismic measurements, 31 profiles of interpreted ground penetrating radar data, 119 boreholes and 472 observation points. The western and south eastern part of the area has a low data density. In the southern parts the data density with respect to estimated bedrock elevation is low. Observation points in this area are generally not very deep and do not describe the actual bedrock elevation. They do, however, describe the minimum soil depth at each location. A detailed topographical DEM, bathymetry and map of Quaternary deposits were also used. The model is based on a three-layer-principle where each layer is assumed to have similar hydrological characteristics. The uppermost layer, Z1, is characterized by the impact from surface processes, roots and biological activity. The bottom layer, Z3, is characterized by contact with the bedrock. The middle layer, Z2, is assumed to have different hydraulic qualities than Z1 and Z3. The lake sediments have been modelled according to six classes of typical deposits. The modelled soil depths show a relatively high bedrock elevation and thus small total soil depth in the major part of the area. The median soil depth has been calculated to 1.9 m, based on model results in areas with higher data density. The maximum modelled soil depth is about 13 m, just north of Lake Stocksjoen. Generally, the sediment layers in the lakes of the area consists of a

Execution programme for the initial site investigations at Forsmark

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-05-01

In the feasibility studies that were completed in 2001, eight sites were identified as potentially suitable for hosting a repository. All the identified sites meet the safety requirements with respect to bedrock conditions that could be checked at that time. The feasibility studies have revealed good potential when it comes to the technical and environmental aspects as well. Based on an integrated evaluation SKB proposed to start site investigations with test drillings at three sites; Forsmark, Simpevarp and Tierp. Site investigations have started at Forsmark and Simpevarp. The municipal council of Tierp voted no to a site investigation in April 2002. The site investigations are divided into two main phases; initial and complete investigations. Initial site investigations are performed to identify the site within a specified area that is deemed to be most suitable for a deep repository and to determine whether the feasibility study's judgement of the suitability of the area holds up in the light of borehole data from repository depth. The initial site investigations are expected to take 1.5-2 years. If the assessment shows that the site has good potential to host a repository, complete site investigations will follow for an expected duration of 3.5-4 years. The purpose of the complete site investigations is to gather all information required to select one of the sites as the main alternative and to apply for a permit for construction of the deep repository at that site. A general programme in which the results from feasibility studies are summarized, the candidate sites presented and the framework of programme for the site investigation phase presented has been published. The general programme, and main references to the programme, specifies which data are required in order to design the repository and carry out a safety assessment, how the investigations should be carried out in order to provide these data, criteria with which the site must comply, as well as

Execution programme for the initial site investigations at Forsmark

International Nuclear Information System (INIS)

2002-05-01

In the feasibility studies that were completed in 2001, eight sites were identified as potentially suitable for hosting a repository. All the identified sites meet the safety requirements with respect to bedrock conditions that could be checked at that time. The feasibility studies have revealed good potential when it comes to the technical and environmental aspects as well. Based on an integrated evaluation SKB proposed to start site investigations with test drillings at three sites; Forsmark, Simpevarp and Tierp. Site investigations have started at Forsmark and Simpevarp. The municipal council of Tierp voted no to a site investigation in April 2002. The site investigations are divided into two main phases; initial and complete investigations. Initial site investigations are performed to identify the site within a specified area that is deemed to be most suitable for a deep repository and to determine whether the feasibility study's judgement of the suitability of the area holds up in the light of borehole data from repository depth. The initial site investigations are expected to take 1.5-2 years. If the assessment shows that the site has good potential to host a repository, complete site investigations will follow for an expected duration of 3.5-4 years. The purpose of the complete site investigations is to gather all information required to select one of the sites as the main alternative and to apply for a permit for construction of the deep repository at that site. A general programme in which the results from feasibility studies are summarized, the candidate sites presented and the framework of programme for the site investigation phase presented has been published. The general programme, and main references to the programme, specifies which data are required in order to design the repository and carry out a safety assessment, how the investigations should be carried out in order to provide these data, criteria with which the site must comply, as well as

Hydrogeology - AQUIFER_SYSTEMS_BEDROCK_IDNR_IN: Bedrock Aquifer Systems of Indiana (Indiana Department of Natural Resources, 1:500,000, Polygon Shapefile)

Data.gov (United States)

NSGIC State | GIS Inventory — AQUIFER_SYSTEMS_BEDROCK_IDNR_IN is a polygon shapefile that shows bedrock aquifer systems of the State of Indiana. The source scale of the map depicting the aquifers...

The suitability of Finnish bedrock to the final disposal of high-level radioactive waste

International Nuclear Information System (INIS)

Vuorela, P.; Hakkarainen, V.

1982-12-01

A regional investigation of the suitability of Finnish bedrock to the final disposal of high-level radioactive waste is described. International geological criteria are applied to Finnish bedrock conditions. The main bedrock units are classified into different areas as concerning to recommendations for further site selection investigations. The Pre-Cambrian crystalline rocks are generally of tight and strong composition and a major problem from the standpoint of waste disposal is fracturing. On the other hand, fractures are quite unevenly distributed in Finland and the bedrock seems to consist of stabile blocks surrounded by fracture zones. Crustal movements between the different bedrock blocks are in Finland at most only tenths of millimeters a year, and the movements are concentrated in the fracture zones. The fracture pattern also controls the hydrogeological system of the bedrock as the main groundwater flow occurs along the fractures. The fracturing thus has an influence on the stability as well as the hydrogeological conditions of the bedrock. The regional recommendations for further site selection studies are based on geological criteria, such as fracturing, seismisity and economic resources. Other criteria, such as topography and erosion, are less significant in comparison. A number of different criteria are likely to prove significant later in more detailed local site investigation studies. The most favorable regions for more detailed investigations contain the granitic rocks of Central Finland and some of them are also to be found in northern and eastern parts of the country. Almost none of the main bedrock units can be classified as completely unsuitable for site selection investigations. Massifs large enough for the final disposal of high-level radioactive waste can be found through detailed surveys in most parts of Finland because of the heterogeneity of the bedrock

Bedrock geology of snyderville basin: Structural geology techniques applied to understanding the hydrogeology of a rapidly developing region, Summit County, Utah

Science.gov (United States)

Keighley, K.E.; Yonkee, W.A.; Ashland, F.X.; Evans, J.P.

1997-01-01

The availability of ground water is a problem for many communities throughout the west. As these communities continue to experience growth, the initial allocation of ground water supplies proves inadequate and may force restrictions on existing, and future, development plans. Much of this new growth relies on ground water supplies extracted from fractured bedrock aquifers. An example of a community faced with this problem is western Summit County, near Park City, Utah, This area has experienced significant water shortages coupled with a 50% growth rate in the past 10-15 years. Recent housing development rests directly on complexly deformed Triassic to Jurassic sedimentary rocks in the hanging wall of the Mount Raymond-Absaroka thrust system. The primary fractured bedrock aquifers are the Nugget Sandstone, and limestones in the Thaynes and Twin Creek Formations. Ground water production and management strategies can be improved if the geometry of the structures and the flow properties of the fractured and folded bedrock can be established. We characterize the structures that may influence ground water flow at two sites: the Pinebrook and Summit Park subdivisions, which demonstrate abrupt changes (less than 1 mi/1.6 km) within the hydrogeologic systems. Geologic mapping at scales of 1:4500 (Pinebrook) and 1:9600 (Summit Park), scanline fracture mapping at the outcrop scale, geologic cross sections, water well data, and structural analysis, provides a clearer picture of the hydrogeologic setting of the aquifers in this region, and has been used to successfully site wells. In the Pinebrook area, the dominate map-scale structures of the area is the Twomile Canyon anticline, a faulted box-like to conical anticline. Widely variable bedding orientations suggest that the fold is segmented and is non-cylindrical and conical on the western limb with a fold axis that plunges to the northwest and also to the southeast, and forms a box-type fold between the middle and eastern

Quantifying in situ stress magnitudes and orientations for Forsmark. Forsmark stage 2.2

International Nuclear Information System (INIS)

Martin, C. Derek

2007-11-01

Stephansson et al. concluded that in the Fennoscandia shield: (1) there is a large horizontal stress component in the uppermost 1,000 m of bedrock, and (2) the maximum and minimum horizontal stresses exceed the vertical stress assuming the vertical stress is estimated from the weight of the overburden. Several stress campaigns involving both overcoring and hydraulic fracturing, including the hydraulic testing of pre-existing fractures (HTPF), have been carried out at Forsmark to establish the in situ stress state. The results from the initial campaigns were summarised by Sjoeberg et al. which formed the bases for the stresses provided in the Site Descriptive Model version 1.2. Since then additional stress measurement campaigns have been completed. The results from these stress measurement campaigns support the conclusions from Stephansson et al. In addition to these in situ stress measurements the following additional studies were undertaken to aid in assessing the stress state at Forsmark. 1. A detailed televiewer survey of approximately 6,900 m of borehole walls to depths of 1,000 m was carried out to assess borehole wall damage, i.e. borehole breakouts. 2. Evaluation of nonlinear strains in laboratory samples to depths of approximately 800 m to assess if stress magnitudes were sufficient to create stress-induced microcracking. 3. Assessment of the magnitudes required to cause core disking and survey of core disking observed at Forsmark. The magnitudes and orientations from the stress measurement campaigns were analysed to establish the most likely stress magnitudes and orientations for Design Step D2 within the Target Area of the Complete Site Investigations. The maximum and minimum horizontal stress components are essentially the same as the maximum and intermediate principal stresses, σ1 and σ2, respectively. The minimum principal stress (σ3) is synonymous with the vertical stress. The most likely range in values to be used in the design is also shown. The

Quantifying in situ stress magnitudes and orientations for Forsmark. Forsmark stage 2.2

Energy Technology Data Exchange (ETDEWEB)

Martin, C. Derek (Univ. of Alberta (Canada))

2007-11-15

Stephansson et al. concluded that in the Fennoscandia shield: (1) there is a large horizontal stress component in the uppermost 1,000 m of bedrock, and (2) the maximum and minimum horizontal stresses exceed the vertical stress assuming the vertical stress is estimated from the weight of the overburden. Several stress campaigns involving both overcoring and hydraulic fracturing, including the hydraulic testing of pre-existing fractures (HTPF), have been carried out at Forsmark to establish the in situ stress state. The results from the initial campaigns were summarised by Sjoeberg et al. which formed the bases for the stresses provided in the Site Descriptive Model version 1.2. Since then additional stress measurement campaigns have been completed. The results from these stress measurement campaigns support the conclusions from Stephansson et al. In addition to these in situ stress measurements the following additional studies were undertaken to aid in assessing the stress state at Forsmark. 1. A detailed televiewer survey of approximately 6,900 m of borehole walls to depths of 1,000 m was carried out to assess borehole wall damage, i.e. borehole breakouts. 2. Evaluation of nonlinear strains in laboratory samples to depths of approximately 800 m to assess if stress magnitudes were sufficient to create stress-induced microcracking. 3. Assessment of the magnitudes required to cause core disking and survey of core disking observed at Forsmark. The magnitudes and orientations from the stress measurement campaigns were analysed to establish the most likely stress magnitudes and orientations for Design Step D2 within the Target Area of the Complete Site Investigations. The maximum and minimum horizontal stress components are essentially the same as the maximum and intermediate principal stresses, sigma1 and sigma2, respectively. The minimum principal stress (sigma3) is synonymous with the vertical stress. The most likely range in values to be used in the design is also

Radon as a groundwater tracer in Forsmark and Laxemar

International Nuclear Information System (INIS)

Grolander, Sara

2009-10-01

Radon concentrations were measured in different water types in Forsmark and Laxemar during the site investigation and within this study. From these measurements it can be concluded that large differences between surface water, near surface groundwater and deep groundwater can be found in both Laxemar and Forsmark. The differences in radon concentrations between different water types are used in this study to detect interactions between surface water, near surface water and deep groundwater. From the radon measurements it can also be concluded that radon concentration in deep groundwater varies largely with depth. These variations with depth are probably caused by groundwater flow in conductive fracture zones in the bedrock. The focus of this study has been the radon concentration of near surface groundwater and the interaction between near surface groundwater and deep groundwater. Radon measurements have been done using the RAD-7 radon detector within this study. It could be concluded that RAD-7 is a good technique for radon measurements and also easy to use in field. The radon concentrations measured in near surface groundwater in Laxemar within this study were low and homogenous. The variation in radon concentration has been analyses and compared to other parameters. Since the hypothesis of this study has been that there are differences in radon concentrations between recharging and discharging groundwater, the most important parameter to consider is the recharge/discharge field classification of the wells. No correlation between the recharge/discharge classifications of wells and the radon concentrations were found. The lack of correlation between groundwater flow patterns and radon concentration means that it is not possible to detect flow patterns in near surface groundwater using radon as a tracer in the Laxemar area. The lack of correlation can be caused by the fact that there are just a few wells located in areas classified as recharge area. It can also be

Human population and activities in Forsmark. Site description

Energy Technology Data Exchange (ETDEWEB)

Miliander, Sofia; Punakivi, Mari; Kylaekorpi, Lasse; Rydgren, Bernt [SwedPower AB, Stockholm (Sweden)

2004-12-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is in the process of selecting a safe and environmentally acceptable location for a deep repository of radioactive waste. Two alternative locations are under investigation. These are Forsmark, Oesthammars kommun (kommun = municipality) and Simpevarp/Laxemar, Oskarshamns kommun. SKB has expressed the importance of describing the humans and their activities in these areas and therefore has this synthesis concerning the human population in Forsmark been produced.The description is a statistical synthesis, mainly based upon statistical data from SCB (Statistics Sweden) that has been collected, processed and analysed. The statistical data has not been verified through site inspections and interviews. When using statistical data, it is advisable to note that the data becomes more unreliable if the areas are small, with small populations.The data in this description is essential for future evaluations of the impact on the environment and its human population (Environmental Impact Assessments). The data is also important when modelling the potential flows of radio nuclides and calculating the risk of exposure in future safety assessments.The actual area for the study is in this report called 'the Forsmark area', an area of 19.5 km{sup 2} near Forsmark nuclear power plant. The land use in the Forsmark area differs notably from the land use in Uppsala laen (laen = county). Only 0.04% of the total area is developed (built-up) compared to 4.9% in Uppsala laen and only 4% is agricultural land compared to 25% in the county. Furthermore, there are far more forest, wetlands and water areas in the Forsmark area. The forest area represents as much as 72.5% of the total area.The Forsmark area is uninhabited, and its surroundings are very sparsely populated. In 2002, the population density in Forsmark was 1.8 inhabitants per square kilometre, which was 24 times lower than in Uppsala laen. The population density in the

Human population and activities in Forsmark. Site description

International Nuclear Information System (INIS)

Miliander, Sofia; Punakivi, Mari; Kylaekorpi, Lasse; Rydgren, Bernt

2004-12-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is in the process of selecting a safe and environmentally acceptable location for a deep repository of radioactive waste. Two alternative locations are under investigation. These are Forsmark, Oesthammars kommun (kommun = municipality) and Simpevarp/Laxemar, Oskarshamns kommun. SKB has expressed the importance of describing the humans and their activities in these areas and therefore has this synthesis concerning the human population in Forsmark been produced.The description is a statistical synthesis, mainly based upon statistical data from SCB (Statistics Sweden) that has been collected, processed and analysed. The statistical data has not been verified through site inspections and interviews. When using statistical data, it is advisable to note that the data becomes more unreliable if the areas are small, with small populations.The data in this description is essential for future evaluations of the impact on the environment and its human population (Environmental Impact Assessments). The data is also important when modelling the potential flows of radio nuclides and calculating the risk of exposure in future safety assessments.The actual area for the study is in this report called 'the Forsmark area', an area of 19.5 km 2 near Forsmark nuclear power plant. The land use in the Forsmark area differs notably from the land use in Uppsala laen (laen = county). Only 0.04% of the total area is developed (built-up) compared to 4.9% in Uppsala laen and only 4% is agricultural land compared to 25% in the county. Furthermore, there are far more forest, wetlands and water areas in the Forsmark area. The forest area represents as much as 72.5% of the total area.The Forsmark area is uninhabited, and its surroundings are very sparsely populated. In 2002, the population density in Forsmark was 1.8 inhabitants per square kilometre, which was 24 times lower than in Uppsala laen. The population density in the parish has been

Water Activities in Forsmark (Part I). Removal of groundwater from final repository for spent fuel; Vattenverksamhet i Forsmark (del I). Bortledande av grundvatten fraan slutfoervarsanlaeggningen foer anvaent kaernbraensle

Energy Technology Data Exchange (ETDEWEB)

Werner, Kent [EmpTec (Sweden); Hamren, Ulrika; Collinder, Per [Ekologigruppen AB (Sweden)

2010-12-15

The construction, operation and decommissioning of the repository for spent nuclear fuel in Forsmark are associated with a number of measures that constitute water operations according to Chapter 11 in the Environmental Code. This report is an appendix to the Environmental Impact Assessment (EIA) and describes water operations in the form of groundwater diversion from the repository (the report is also included in the permit application according to the Nuclear Activities Act). The main objective of the report is to describe hydrogeological and hydrological effects and the consequences that may arise in the surroundings of the repository due to the groundwater diversion. Moreover, the report presents prevention measures to reduce the effects of the groundwater diversion and mitigation measures that aim at its consequences

Displacement along extensive deformation zones at the two SKB sites: Forsmark and Laxemar

International Nuclear Information System (INIS)

Beckholmen, Monica; Tiren, Sven A.

2010-12-01

The Fennoscandian shield, a part of the East European Craton, is distinguished by the exposed bedrock which is mainly composed of Precambrian metamorphic and igneous rocks. Large parts of the ground surface closely coincides with a late Precambrian denudation surface; the sub-Cambrian peneplain. Palaeozoic and younger sediments were deposited on the peneplain but these sediments have been removed from most areas that now form the mainland of Sweden and Finland and there are just a few remnants left. In the Baltic Sea, located in large-scale depressions on the boundary of in the Fennoscandian Shield/ in the East European Craton/, the Precambrian bedrock is still in large parts covered by Palaeozoic sediments. The Palaeozoic sedimentary rocks, as they are well bedded, may form a memory of the late Palaeozoic and younger tectonic events in the underlying basement rocks. Such data are used here to complement the structural observations made at sites located on the mainland, giving information on displacement along faults. Significant for the Baltic Sea are faults oriented in N-S that appear as segments, displaced relative to each other. Other structures are oriented in E-W, NE-SW and NW-SE. The SKB Forsmark site is located in a relatively flat coastal area within the sub-Cambrian peneplain. The sea area at the Forsmark site has a more accentuated relief than what is found on the mainland, for example, a furrow along the western side of the N-S oriented island Graesoe northeast of Forsmark (below 30m b.s.l. and locally more than 50m lower than Graesoe) and the deep between Aaland and Sweden (301m b.s.l.) about 100km east-southeast of Forsmark. In the Forsmark-site area two sets of structures interfere: a WNWESE trending set with relatively straight faults along the north coast of Uppland and a NNW-SSE to N-S trending set, slightly curved, along the (north)east coast of Uppland. The Forsmark site is located in an elevated WNW trending lath-shaped rock block outlined by

Displacement along extensive deformation zones at the two SKB sites: Forsmark and Laxemar

Energy Technology Data Exchange (ETDEWEB)

Beckholmen, Monica; Tiren, Sven A. (GEOSIGMA AB (Sweden))

2010-12-15

The Fennoscandian shield, a part of the East European Craton, is distinguished by the exposed bedrock which is mainly composed of Precambrian metamorphic and igneous rocks. Large parts of the ground surface closely coincides with a late Precambrian denudation surface; the sub-Cambrian peneplain. Palaeozoic and younger sediments were deposited on the peneplain but these sediments have been removed from most areas that now form the mainland of Sweden and Finland and there are just a few remnants left. In the Baltic Sea, located in large-scale depressions on the boundary of in the Fennoscandian Shield/ in the East European Craton/, the Precambrian bedrock is still in large parts covered by Palaeozoic sediments. The Palaeozoic sedimentary rocks, as they are well bedded, may form a memory of the late Palaeozoic and younger tectonic events in the underlying basement rocks. Such data are used here to complement the structural observations made at sites located on the mainland, giving information on displacement along faults. Significant for the Baltic Sea are faults oriented in N-S that appear as segments, displaced relative to each other. Other structures are oriented in E-W, NE-SW and NW-SE. The SKB Forsmark site is located in a relatively flat coastal area within the sub-Cambrian peneplain. The sea area at the Forsmark site has a more accentuated relief than what is found on the mainland, for example, a furrow along the western side of the N-S oriented island Graesoe northeast of Forsmark (below 30m b.s.l. and locally more than 50m lower than Graesoe) and the deep between Aaland and Sweden (301m b.s.l.) about 100km east-southeast of Forsmark. In the Forsmark-site area two sets of structures interfere: a WNWESE trending set with relatively straight faults along the north coast of Uppland and a NNW-SSE to N-S trending set, slightly curved, along the (north)east coast of Uppland. The Forsmark site is located in an elevated WNW trending lath-shaped rock block outlined by

Evaluation of the state of stress at the Forsmark site. Preliminary site investigation Forsmark area - version 1.2

Energy Technology Data Exchange (ETDEWEB)

Sjoeberg, Jonny; Lindfors, Ulf; Perman, Fredrik; Ask, Daniel [SwedPower AB, Stockholm (Sweden)

2005-09-15

horizontal stress was found in gneissic rock. Aside from this, clear correlations between rock type and measured stresses were also lacking, as well as confirmatory evidence of a low-stress environment in the superficial, more fractured bedrock. Assessment of a representative stress state for the Forsmark site was based on different subsets of the total data set of stress measurements. Linear stress profiles were assumed for the horizontal and vertical stress components, with each stress profile being representative of the conditions within the tectonic lens. These stress profiles define the lower and upper limit of the stress state based on the data considered reliable for each stress component. The resulting stress profiles are: Maximum horizontal stress ({sigma}H) applicable for 230-450 m vertical depth (z): Lower limit: {sigma}H = 0.085z (MPa), Upper limit: {sigma}H = 13+0.095z (MPa), Alternative upper limit: {sigma}H 29+0.050z (MPa). Orientation: 140 deg (clockwise from North). Minimum horizontal stress ({sigma}h) applicable for 0-1,000 m vertical depth (z): Lower limit: {sigma}h = 0.022z (MPa), Upper limit: {sigma}h 5.5+0.0265z (MPa). Vertical stress ({sigma}v) applicable for 0-800 m vertical depth (z): {sigma}v = 0.0265z (MPa). Future measurements and activities should be planned to address the gaps indicated by the present data set. It is recommended that new overcoring measurements are conducted, starting already at approximately 100 m depth below the ground surface, and continued as deep as possible - until the method is no longer applicable (extensive core damage and/or core discing inhibiting correct installation and/or overcoring of the measurement probe). Furthermore, any observations on core discing should be logged in detail to provide confirmatory evidence of stress magnitudes. If core discing of solid core is observed, pilot hole drilling with subsequent overcoring (without installation of the measurement probe) should be considered to induce ring discing

Evaluation of the state of stress at the Forsmark site. Preliminary site investigation Forsmark area - version 1.2

International Nuclear Information System (INIS)

Sjoeberg, Jonny; Lindfors, Ulf; Perman, Fredrik; Ask, Daniel

2005-09-01

gneissic rock. Aside from this, clear correlations between rock type and measured stresses were also lacking, as well as confirmatory evidence of a low-stress environment in the superficial, more fractured bedrock. Assessment of a representative stress state for the Forsmark site was based on different subsets of the total data set of stress measurements. Linear stress profiles were assumed for the horizontal and vertical stress components, with each stress profile being representative of the conditions within the tectonic lens. These stress profiles define the lower and upper limit of the stress state based on the data considered reliable for each stress component. The resulting stress profiles are: Maximum horizontal stress (σH) applicable for 230-450 m vertical depth (z): Lower limit: σH = 0.085z (MPa), Upper limit: σH = 13+0.095z (MPa), Alternative upper limit: σH 29+0.050z (MPa). Orientation: 140 deg (clockwise from North). Minimum horizontal stress (σh) applicable for 0-1,000 m vertical depth (z): Lower limit: σh = 0.022z (MPa), Upper limit: σh 5.5+0.0265z (MPa). Vertical stress (σv) applicable for 0-800 m vertical depth (z): σv = 0.0265z (MPa). Future measurements and activities should be planned to address the gaps indicated by the present data set. It is recommended that new overcoring measurements are conducted, starting already at approximately 100 m depth below the ground surface, and continued as deep as possible - until the method is no longer applicable (extensive core damage and/or core discing inhibiting correct installation and/or overcoring of the measurement probe). Furthermore, any observations on core discing should be logged in detail to provide confirmatory evidence of stress magnitudes. If core discing of solid core is observed, pilot hole drilling with subsequent overcoring (without installation of the measurement probe) should be considered to induce ring discing of a hollow core. Having two observations of different core geometries can

SFR site investigation. Bedrock Hydrogeochemistry

International Nuclear Information System (INIS)

Nilsson, Ann-Chatrin; Tullborg, Eva-Lena; Smellie, John; Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F.; Sandstroem, Bjoern; Pedersen, Karsten

2011-11-01

There are plans that the final repository for low and intermediate level radioactive waste, SFR, located about 150 km north of Stockholm, will be extended. Geoscientific studies to define and characterise a suitable bedrock volume for the extended repository have been carried out from 2007 to 2011, and have included the drilling and evaluation of seven new core drilled and four percussion boreholes. These new data, together with existing data extending back to 1985, have been interpreted and modelled in order to provide the necessary information for safety assessment and repository design. This report presents the final hydrogeochemical site description for the SFR site, and will constitute a background report for the integrated site description (the SFR Site Descriptive Model version 1.0) together with corresponding reports from the geological and hydrogeological disciplines. Most of the hydrogeochemical data from the field investigations consist of major ions and isotopes together with sporadic gas, microbe and measured redox data. Despite the close proximity of the Forsmark site, few data from this source are of relevance because of the shallow nature of the SFR site, the fact that SFR is located beneath the Baltic Sea and also the drawdown/upconing impacts of its construction on the hydrogeochemistry. This artificially imposed dynamic flow system is naturally more prevalent along major deformation fracture zones of higher transmissivity, whilst lower transmissive fractures together with the less transmissive bedrock masses between major deformation zones, still retain some evidence of the natural groundwater mixing patterns established prior to the SFR construction. The groundwaters in the SFR dataset cover a depth down to -250 m.a.s.l. with single sampling locations at -300 and -400 m.a.s.l. and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the δ 18 O values show a wide variation (-15.5 to -7.5 per mille V

SFR site investigation. Bedrock Hydrogeochemistry

Energy Technology Data Exchange (ETDEWEB)

Nilsson, Ann-Chatrin [Geosigma AB, Uppsala (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden); Smellie, John [Conterra AB, Uppsala (Sweden); Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F. [Univ. of Zaragoza, Zaragoza (Spain); Sandstroem, Bjoern [WSP Sverige AB, Goeteborg (Sweden); Pedersen, Karsten [Micans AB, Moelnlycke (Sweden)

2011-11-15

There are plans that the final repository for low and intermediate level radioactive waste, SFR, located about 150 km north of Stockholm, will be extended. Geoscientific studies to define and characterise a suitable bedrock volume for the extended repository have been carried out from 2007 to 2011, and have included the drilling and evaluation of seven new core drilled and four percussion boreholes. These new data, together with existing data extending back to 1985, have been interpreted and modelled in order to provide the necessary information for safety assessment and repository design. This report presents the final hydrogeochemical site description for the SFR site, and will constitute a background report for the integrated site description (the SFR Site Descriptive Model version 1.0) together with corresponding reports from the geological and hydrogeological disciplines. Most of the hydrogeochemical data from the field investigations consist of major ions and isotopes together with sporadic gas, microbe and measured redox data. Despite the close proximity of the Forsmark site, few data from this source are of relevance because of the shallow nature of the SFR site, the fact that SFR is located beneath the Baltic Sea and also the drawdown/upconing impacts of its construction on the hydrogeochemistry. This artificially imposed dynamic flow system is naturally more prevalent along major deformation fracture zones of higher transmissivity, whilst lower transmissive fractures together with the less transmissive bedrock masses between major deformation zones, still retain some evidence of the natural groundwater mixing patterns established prior to the SFR construction. The groundwaters in the SFR dataset cover a depth down to -250 m.a.s.l. with single sampling locations at -300 and -400 m.a.s.l. and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the {delta}{sup 18}O values show a wide variation (-15.5 to -7.5 per mille V

Hydrogeologic framework of the middle San Pedro watershed, southeastern Arizona

Science.gov (United States)

Dickinson, Jesse; Kennedy, Jeffrey R.; Pool, D.R.; Cordova, Jeffrey T.; Parker, John T.; Macy, J.P.; Thomas, Blakemore

2010-01-01

Water managers in rural Arizona are under increasing pressure to provide sustainable supplies of water despite rapid population growth and demands for environmental protection. This report describes the results of a study of the hydrogeologic framework of the middle San Pedro watershed. The components of this report include: (1) a description of the geologic setting and depositional history of basin fill sediments that form the primary aquifer system, (2) updated bedrock altitudes underlying basin fill sediments calculated using a subsurface density model of gravity data, (3) delineation of hydrogeologic units in the basin fill using lithologic descriptions in driller's logs and models of airborne electrical resistivity data, (4) a digital three-dimensional (3D) hydrogeologic framework model (HFM) that represents spatial extents and thicknesses of the hydrogeologic units (HGUs), and (5) description of the hydrologic properties of the HGUs. The lithologic interpretations based on geophysical data and unit thickness and extent of the HGUs included in the HFM define potential configurations of hydraulic zones and parameters that can be incorporated in groundwater-flow models. The hydrogeologic framework comprises permeable and impermeable stratigraphic units: (1) bedrock, (2) sedimentary rocks predating basin-and-range deformation, (3) lower basin fill, (4) upper basin fill, and (5) stream alluvium. The bedrock unit includes Proterozoic to Cretaceous crystalline rocks, sedimentary rocks, and limestone that are relatively impermeable and poor aquifers, except for saturated portions of limestone. The pre-basin-and-range sediments underlie the lower basin fill but are relatively impermeable owing to cementation. However, they may be an important water-bearing unit where fractured. Alluvium of the lower basin fill, the main water-bearing unit, was deposited in the structural trough between the uplifted ridges of bedrock and (or) pre-basin-and-range sediments. Alluvium of

Monitoring Forsmark. Moose age composition, reproduction and antler development in Forsmark

International Nuclear Information System (INIS)

Cederlund, Goeran; Broman, Emil

2011-05-01

The moose (Alces alces) is an important game species in Forsmark, as well as in Sweden in general. Hunting on moose is subject to strict local regulations and restrictions within a management program. Such restrictions will have considerable effects on demography. This has led to a moose population in Forsmark with biased sex ratio with fewer adult males than females and a generally low average age. High hunting pressure on males has caused a low survival rate and the chance to survive more than five years is just a few percent. Restrictions in hunting pressure on females have caused a generally higher survival rate and a higher average age compared to males. Sex differences in body mass are normal compared to other populations in southern Sweden. Mean body mass of culled calves is an important measure of quality of the population, since it reflects the available food resources in the management area. Body mass among calves in Forsmark is generally low, indicating a deteriorated food resource due to either ambient population density and/or hampered food production in the forest. The average reproduction rate is normal compared to other populations in this part of Sweden. However, one year old females (yearlings) have a fairly low production of eggs per female (ovulation rate). As the yearlings constitute a considerable part of the population in Forsmark, their lowered ovulation rate will affect the rate of recruitment of calves to the local population. The moose population seems to have been subject to considerable variation in density during the last decade, which is probably a joint effect of changes in demography (hunting), changes in food resources due to forestry management and by food competition from other browsers in the area. Local managers believe that the population has reached such a low level (although not verified by surveys) that the number of moose has to be increased. It is vital to stress the importance of keeping up collection of data from the

Assessment of site-scale hydrogeological modelling possibilities in crystalline hard rock for safety appraisal

Energy Technology Data Exchange (ETDEWEB)

Geier, J. [Cleanwater Hardrock Consulting, Corvallis, OR (United States); Luukkonen, A.

2012-09-15

This review describes the state-of-the-art in hydrogeological modelling for safety-case studies related to spent-fuel repositories in crystalline hard rock, focusing on issues of relevance for the KBS-3 disposal concept in Nordic environments. The review includes a survey of model capabilities and assumptions regarding groundwater flow processes, geological and excavation-related features, and boundary conditions for temperate, periglacial, and glacial climates. Modelling approaches are compared for research sites including the Stripa mine (Sweden), the Grimsel Test Site (Switzerland), the Whiteshell Underground Research Laboratory (Canada), the Aspo Hard Rock Laboratory and Simpevarp-Laxemar site (Sweden), the Forsmark site (Sweden), the Waste Isolation Pilot Plant site (USA), and Olkiluoto (Finland). Current hydrogeological models allow realistic representations, but are limited by availability of data to constrain their properties. Examples of calibrations of stochastic representations of heterogeneity are still scarce. Integrated models that couple flow and non-reactive transport are now well established, particularly those based on continuum representations. Models that include reactive transport are still mainly in the realm of research tools. Thus far, no single software tool allows fully coupled treatment of all relevant thermal, hydraulic, mechanical, and chemical transport processes in the bedrock, together with climate-related physical processes at the ground surface, and with explicit treatment of bedrock heterogeneity. Hence practical applications require combinations of models based on different simplifications. Key improvements can be expected in treatment of the unsaturated zone, simulation of heterogeneous infiltration at the surface, and hydromechanical coupling. Significant advances have already been made in the amounts and types of data that can be used in site-scale models, including large datasets to define topography and other surface

Background complementary hydrogeochemical studies. SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Kalinowski, Birgitta E. (ed.)

2008-08-15

The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are one of the major driving forces for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, uranium, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise

Fracture mineralogy of the Forsmark site. SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Sandstroem, Bjoern (Dept. of Earth Sciences, Univ. of Goeteborg (Sweden)); Tullborg, Eva-Lena (Terralogica AB, Graabo (Sweden)); Smellie, John (Conterra AB, Luleaa (Sweden)); MacKenzie, Angus B. (SUERC, Scottish Enterprise Technology Park, East Kilbride (United Kingdom)); Suksi, Juhani (Dept. of Chemistry, Univ. of Helsinki, Helsinki (Finland))

2008-08-15

Detailed investigations of the fracture mineralogy and altered wall rock have been carried out as part of the site characterisation programme between 2003 and 2007 at Forsmark. The results have been published in a number of P-reports and in contributions to scientific journals. This report summarises and evaluates the data obtained during the detailed fracture mineralogical studies. The report includes descriptions of the identified fracture minerals and their chemical composition. A sequence of fracture mineralisations has been distinguished and provides information of the low to moderate temperature (brittle) geological and hydrogeological evolution at the site. Special focus has been paid to the chemical and stable isotopic composition of calcite to obtain palaeohydrogeological information. Chemical analyses of bulk fracture filling material have been carried out to identify possible sinks for certain elements and also to reveal the presence of minor phases rich in certain elements which have not been possible to detect by X-ray diffraction (XRD). Statistical analysis of the mineralogy in fractures outside deformation zones (i.e. within fracture domains FFM01, FFM02, FFM03 and FFM06) have been carried out concerning variation of fracture mineral distribution at depth and in different fracture domains. Uranium contents and uranium-series isotopes have been analysed on fracture coating material from hydraulically conductive fractures. Such analyses are also available from the groundwaters and the results are combined in order to reveal recent (< 1 Ma) removal/deposition of uranium in the fracture system. The redox conditions in the fracture system have been evaluated based on mineralogical and chemical indicators as well as Moessbauer analyses

Hydrogeology of Valley-Fill Aquifers and Adjacent Areas in Eastern Chemung County, New York

Science.gov (United States)

Heisig, Paul M.

2015-10-19

The extent, hydrogeologic framework, and potential well yields of valley-fill aquifers within a 151-square-mile area of eastern Chemung County, New York, were investigated, and the upland distribution of till thickness over bedrock was characterized. The hydrogeologic framework of these valleyfill aquifers was interpreted from multiple sources of surficial and subsurface data and an interpretation of the origin of the glacial deposits, particularly during retreat of glacial ice from the region. Potential yields of screened wells are based on the hydrogeologic framework interpretation and existing well-yield data, most of which are from wells finished with open-ended well casing.

Safety-related site characteristics - a relative comparison of the Forsmark reference areas; Saekerhetsrelaterade platsegenskaper - en relativ jaemfoerelse av Forsmark med referensomraaden

Energy Technology Data Exchange (ETDEWEB)

Winberg, Anders (Conterra AB, Uppsala (Sweden))

2010-12-15

SKB has over the years from 2002 to 2008 conducted site investigations in Forsmark and Laxemar, with associated site modeling, design and safety analysis. In mid-2009 Forsmark was selected on the basis of analysis made as site for a future repository for spent nuclear fuel. Based on defined safety-related geoscientific location factors data from Forsmark are compared in relative terms with data from a number of locations in Sweden, previously studied by SKB. The factors compared include: the rock's composition and structures, future climate evolution, rock mechanical conditions, earthquakes, groundwater flow, groundwater composition, delay of solutes, and the ability to characterize and describe the location. Past comparisons of these properties for the selected sites show that none of these sites collectively show any significant benefit over Forsmark site for a repository. This does not preclude that there may be places on the basis of an overall assessment of geoscientific location factors could be equivalent to Forsmark

Forsmark NPP I and C modernization strategy

International Nuclear Information System (INIS)

Hallen, J.; Rydahl, I.; Kloow, L.

2003-01-01

By the year 2000, the Forsmark NPP was halfway through the planned plant life. As early as 1995, Forsmark realized that the old analog I and C equipment would need to be replaced before 2005. At the Forsmark NPP they had strength of a vision of an integrated modernization and a strategy to reach the vision. Without vision and strategy, the plant could end up with a fragmented plant I and C-architecture that is not cost-effective or operable. This paper will address several questions that led to the current modernization program in Forsmark, the more important questions are: What would happen if the modernization would be postponed? Which main requirements were to be achieved by means of the modernization strategy? The goal of a completed plant modernization program is a totally integrated system solution and what factors were considered during the modernization? How to gain acceptance from the operational staff in designing Control Room and Soft Control Displays? What are the important roles for the staff and organization to reach the end goal? What has been the experience to date and what are the lessons learned? Thanks to the long term co-operation between Forsmark and Westinghouse the modernization has been very successful for both parties. (orig.)

Application of the Drilling Impact Study (DIS) to Forsmark groundwaters

International Nuclear Information System (INIS)

Gascoyne, Mel; Gurban, Ioana

2008-01-01

Characterisation of a geological formation as a repository for nuclear fuel waste requires deep drilling into the bedrock to gain an understanding of the geological structure, rock types, groundwater flow and the chemical composition of groundwater and the adjacent rock. The methods of characterisation from a hydrogeochemical point of view, might be affected by the various drilling activities and techniques for determining groundwater composition have been employed so that the composition can be corrected for these activities. SKB has developed and supported the Drilling Impact Study (DIS) project in which a tracer is used as an indicator of contamination to attempt to correct the groundwater composition for dilution or contamination by surface waters. The project began about five years ago with the intention of developing a routine method for determining the extent of contamination of borehole groundwater by drilling water. The main objectives of this work were: 1. Determine the extent of drilling water contamination in permeable zones in a test borehole on the Forsmark site. 2. Correct measured chemical compositions of the groundwaters based on contamination results. 3. Provide a workable methodology for routine correction of groundwater composition. 4. Apply the modified DIS model to suitable borehole zones at the Forsmark site in a systematic fashion 5. Determine uncertainties in DIS modelling. A memorandum was prepared by describing the characteristics of borehole KFM06 and its drilling history. Estimates were made of the amount of drilling water in permeable zones in the borehole and the various approaches to applying results of DIS were described and recommendations made, with an example calculation

Forsmark site investigation. Programme for further investigations of geosphere and biosphere

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-01-01

of the geological and ecological conditions in the area has largely been completed. In order to investigate the bedrock at depth, five deep (1,000 m) and two shallower cored boreholes have been drilled and documented. Drilling of a sixth deep cored borehole is under way. 19 percussion boreholes have been drilled, partly to supply core drilling with flushing water and partly to investigate the bedrock. A comprehensive, preliminary site description (version 1.1) has been published. The work of compiling all information from the initial site investigation is under way and will result in version 1.2 of the site description. The consultation process for a possible deep repository in Forsmark has been established in accordance with the provisions of the Environmental Code. An active information and communication programme has been established for ongoing dialogue with nearby residents, the public, Oesthammar Municipality, neighbouring municipalities and other local stakeholders.

Forsmark site investigation. Programme for further investigations of geosphere and biosphere

International Nuclear Information System (INIS)

2005-01-01

geological and ecological conditions in the area has largely been completed. In order to investigate the bedrock at depth, five deep (1,000 m) and two shallower cored boreholes have been drilled and documented. Drilling of a sixth deep cored borehole is under way. 19 percussion boreholes have been drilled, partly to supply core drilling with flushing water and partly to investigate the bedrock. A comprehensive, preliminary site description (version 1.1) has been published. The work of compiling all information from the initial site investigation is under way and will result in version 1.2 of the site description. The consultation process for a possible deep repository in Forsmark has been established in accordance with the provisions of the Environmental Code. An active information and communication programme has been established for ongoing dialogue with nearby residents, the public, Oesthammar Municipality, neighbouring municipalities and other local stakeholders

Arsenic in groundwater of Licking County, Ohio, 2012—Occurrence and relation to hydrogeology

Science.gov (United States)

Thomas, Mary Ann

2016-02-23

Arsenic concentrations were measured in samples from 168 domestic wells in Licking County, Ohio, to document arsenic concentrations in a wide variety of wells and to identify hydrogeologic factors associated with arsenic concentrations in groundwater. Elevated concentrations of arsenic (greater than 10.0 micrograms per liter [µg/L]) were detected in 12 percent of the wells (about 1 in 8). The maximum arsenic concentration of about 44 µg/L was detected in two wells in the same township.A subset of 102 wells was also sampled for iron, sulfate, manganese, and nitrate, which were used to estimate redox conditions of the groundwater. Elevated arsenic concentrations were detected only in strongly reducing groundwater. Almost 20 percent of the samples with iron concentrations high enough to produce iron staining (greater than 300 µg/L) also had elevated concentrations of arsenic.In groundwater, arsenic primarily occurs as two inorganic species—arsenite and arsenate. Arsenic speciation was determined for a subset of nine samples, and arsenite was the predominant species. Of the two species, arsenite is more difficult to remove from water, and is generally considered to be more toxic to humans.Aquifer and well-construction characteristics were compiled from 99 well logs. Elevated concentrations of arsenic (and iron) were detected in glacial and bedrock aquifers but were more prevalent in glacial aquifers. The reason may be that the glacial deposits typically contain more organic carbon than the Paleozoic bedrock. Organic carbon plays a role in the redox reactions that cause arsenic (and iron) to be released from the aquifer matrix. Arsenic concentrations were not significantly different for different types of bedrock (sandstone, shale, sandstone/shale, or other). However, arsenic concentrations in bedrock wells were correlated with two well-construction characteristics; higher arsenic concentrations in bedrock wells were associated with (1) shorter open intervals and

Synthetic Study on the Geological and Hydrogeological Model around KURT

International Nuclear Information System (INIS)

Park, Kyung Woo; Kim, Kyung Su; Koh, Yong Kwon; Choi, Jong Won

2011-01-01

To characterize the site specific properties of a study area for high-level radioactive waste disposal research in KAERI, the several geological investigations such as surface geological surveys and borehole drillings were carried out since 1997. Especially, KURT (KAERI Underground Research Tunnel) was constructed to understand the further study of geological environments in 2006. As a result, the first geological model of a study area was constructed by using the results of geological investigation. The objective of this research is to construct a hydrogeological model around KURT area on the basis of the geological model. Hydrogeological data which were obtained from in-situ hydraulic tests in the 9 boreholes were estimated to accomplish the objective. And, the hydrogeological properties of the 4 geological elements in the geological model, which were the subsurface weathering zone, the log angle fracture zone, the fracture zones and the bedrock were suggested. The hydrogeological model suggested in this study will be used as input parameters to carry out the groundwater flow modeling as a next step of the site characterization around KURT area

Complementary modelling of radionuclide retention in the near-surface system at Forsmark. Development of a reactive transport model using Forsmark 1.2 data

Energy Technology Data Exchange (ETDEWEB)

Sena, Clara; Grandia, Fidel; Arcos, David; Molinero, Jorge; Duro, Lara (Amphos XXI Consulting S.L., Barcelona (Spain))

2008-10-15

The Swedish Nuclear Fuel and Waste Management Company (SKB) is conducting a comprehensive geoscientific characterization of two alternative sites to allocate a deep geological repository of high level nuclear waste. The Site Characterization Program also includes the near-surface systems, which are expected to constitute the last geological barrier between the repository system and the earth's surface. The evaluation of the retention capacity of the near surface systems is, therefore, very relevant for the site characterization program. From the geological point of view, near-surface systems in the Forsmark area consist of Quaternary deposits that overlay a granitic bedrock. Glacial till is the most abundant outcropping Quaternary deposit (approx75% of surface extension) and the remainder is made up of clayey materials (glacial and post-glacial clays). These types of near-surface sediments show distinctive hydraulic and geochemical features. The main reactive mineral in the till deposits, for the time scale considered in this work, is calcium carbonate (calcite). This mineral is found along with clay minerals (e.g. illite) and Fe(III) hydroxides. In contrast, glacial and post-glacial clays are basically composed of illite with minor amounts of calcium carbonate, and containing organic matter-rich levels (gyttja) which can promote reducing conditions in the system. The assessment of the migration behaviour of selected long-lived radionuclides through the near-surface system of Forsmark was developed in an earlier work, that focused on the evaluation of the capacity of the Quaternary deposits for radionuclide retention. The work reported here is an improvement of the geochemical conceptual and numerical model already presented, based on data available in the Site Descriptive Model v 1.2 (Forsmark). Regarding the geochemical variability of the Quaternary deposits present at Forsmark and its implications on radionuclide mobility through the near-surface systems, a

Discrete-Feature Model Implementation of SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Geier, Joel (Clearwater Hardrock Consulting, Corvallis, OR (United States))

2010-03-15

A discrete-feature model (DFM) was implemented for the Forsmark repository site based on the final site descriptive model from surface based investigations. The discrete-feature conceptual model represents deformation zones, individual fractures, and other water-conducting features around a repository as discrete conductors surrounded by a rock matrix which, in the present study, is treated as impermeable. This approximation is reasonable for sites in crystalline rock which has very low permeability, apart from that which results from macroscopic fracturing. Models are constructed based on the geological and hydrogeological description of the sites and engineering designs. Hydraulic heads and flows through the network of water-conducting features are calculated by the finite-element method, and are used in turn to simulate migration of non-reacting solute by a particle-tracking method, in order to estimate the properties of pathways by which radionuclides could be released to the biosphere. Stochastic simulation is used to evaluate portions of the model that can only be characterized in statistical terms, since many water-conducting features within the model volume cannot be characterized deterministically. Chapter 2 describes the methodology by which discrete features are derived to represent water-conducting features around the hypothetical repository at Forsmark (including both natural features and features that result from the disturbance of excavation), and then assembled to produce a discrete-feature network model for numerical simulation of flow and transport. Chapter 3 describes how site-specific data and repository design are adapted to produce the discrete-feature model. Chapter 4 presents results of the calculations. These include utilization factors for deposition tunnels based on the emplacement criteria that have been set forth by the implementers, flow distributions to the deposition holes, and calculated properties of discharge paths as well as

Discrete-Feature Model Implementation of SDM-Site Forsmark

International Nuclear Information System (INIS)

Geier, Joel

2010-03-01

A discrete-feature model (DFM) was implemented for the Forsmark repository site based on the final site descriptive model from surface based investigations. The discrete-feature conceptual model represents deformation zones, individual fractures, and other water-conducting features around a repository as discrete conductors surrounded by a rock matrix which, in the present study, is treated as impermeable. This approximation is reasonable for sites in crystalline rock which has very low permeability, apart from that which results from macroscopic fracturing. Models are constructed based on the geological and hydrogeological description of the sites and engineering designs. Hydraulic heads and flows through the network of water-conducting features are calculated by the finite-element method, and are used in turn to simulate migration of non-reacting solute by a particle-tracking method, in order to estimate the properties of pathways by which radionuclides could be released to the biosphere. Stochastic simulation is used to evaluate portions of the model that can only be characterized in statistical terms, since many water-conducting features within the model volume cannot be characterized deterministically. Chapter 2 describes the methodology by which discrete features are derived to represent water-conducting features around the hypothetical repository at Forsmark (including both natural features and features that result from the disturbance of excavation), and then assembled to produce a discrete-feature network model for numerical simulation of flow and transport. Chapter 3 describes how site-specific data and repository design are adapted to produce the discrete-feature model. Chapter 4 presents results of the calculations. These include utilization factors for deposition tunnels based on the emplacement criteria that have been set forth by the implementers, flow distributions to the deposition holes, and calculated properties of discharge paths as well as

Validation of the marine vegetation model in Forsmark. SFR-Site Forsmark

International Nuclear Information System (INIS)

Aquilonius, Karin; Qvarfordt, Susanne; Borgiel, Micke

2011-04-01

A regression model implemented in GIS of the marine vegetation in Forsmark were developed by SKB /Aquilonius 2010/ based on field investigations and video surveys /Fredriksson 2005/ and from correlations of field data and physical properties /Carlen et al. 2007/. The marine vegetation model describes distribution and biomasses of the marine vegetation and is used as input data in the dose modeling within the safety assessments performed by the SKB. In this study the predictive performance of the vegetation model in the less examined parts of the marine area in Forsmark is evaluated. In general, the vegetation model works very well in predicting absence of biomass, except for Red algae. In total and for Fucus sp., the model also predicts the observed biomass fairly well. However, for phanerogams, Chara sp., filamentous algae and red algae the vegetation model works less well in predicting biomass

Validation of the marine vegetation model in Forsmark. SFR-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Aquilonius, Karin (Studsvik Nuclear AB (Sweden)); Qvarfordt, Susanne; Borgiel, Micke (Sveriges Vattenekologer AB (Sweden))

2011-04-15

A regression model implemented in GIS of the marine vegetation in Forsmark were developed by SKB /Aquilonius 2010/ based on field investigations and video surveys /Fredriksson 2005/ and from correlations of field data and physical properties /Carlen et al. 2007/. The marine vegetation model describes distribution and biomasses of the marine vegetation and is used as input data in the dose modeling within the safety assessments performed by the SKB. In this study the predictive performance of the vegetation model in the less examined parts of the marine area in Forsmark is evaluated. In general, the vegetation model works very well in predicting absence of biomass, except for Red algae. In total and for Fucus sp., the model also predicts the observed biomass fairly well. However, for phanerogams, Chara sp., filamentous algae and red algae the vegetation model works less well in predicting biomass

Numerical modeling of the hydrogeological effects of ONKALO in 2009

International Nuclear Information System (INIS)

Raemae, T.

2011-10-01

The underground rock characterization facility ONKALO is currently being excavated in the bedrock of the Olkiluoto Island. The construction work of the ONKALO begun in 2004 and the tunnel will remain open for the whole period of the operation of the planned repository for spent nuclear fuel. The open tunnels cause a disturbance on the local groundwater system. The leakage water flowing into the open tunnels withdraw water from the bedrock and locally alter the natural flow routes. One of the possible consequences of the convergent flow towards the ONKALO is that the highly saline deeper groundwater might be drawn towards the ONKALO, this process is called upconing. The purpose of this work is to estimate the possible upconing of the deep saline waters up to the repository level. A numerical flow and transport simulation is conducted with conservative approach to ensure overestimation of the effects of the ONKALO. In this study a 3D model of the hydrogeological system of the Olkiluoto is used as the basis for numerical flow and transport modeling of the saline groundwater movement in the bedrock of Olkiluoto. The numerical modelling is conducted using the commercial Comsol 3.5a code. The modelled geometry of the ONKALO includes the already excavated ONKALO and the extension according to the layout plan used in this work. The ONKALO and the hydrogeological zones are simplified for this study. In addition the used hydrogeological zones are modelled as 3D blocks with constant thickness of 50 meters. With the used boundary conditions upconing occurs even with the lowest leakage values. The influence of the leakage water is small on the maximum TDS-value at the depth near ONKALO. In this work this phenomenon is explained by the increase in the fresh water infiltration rate as the leakage water is increased, since the low density fresh water is transported more easily downwards than the high density saline water transported upwards towards the ONKALO. Further away from

Solute transport in coupled inland-coastal water systems. General conceptualisation and application to Forsmark

International Nuclear Information System (INIS)

Jarsjoe, Jerker; Destouni, Georgia; Persson, Klas; Prieto, Carmen

2007-12-01

diffuse and occurring through SGD, small transient streams and/or coastal wetlands. Regarding transport quantifications, hydrogeochemical characteristics and pollution source loads may generally differ between larger, monitored catchments and smaller unmonitored coastal catchments. Since national hydrological monitoring data systematically exclude smaller, coastal catchments, they may not be representative for conditions in Forsmark (or Laxemar-Simpevarp). This emphasises the importance of extending in time the recently started hydrological and hydrogeochemical data series in the Forsmark and Laxemar-Simpevarp coastal catchment areas, since they are in effect unmonitored from a hydrological viewpoint, due to the lack of extended discharge time series. In the performed initial demonstration analysis of solute transport pathways from deep groundwater to recipients at the surface, we considered the main scenarios: (I) transport in the Quaternary deposits-bedrock interface zone only, and (II) transport in the coupled groundwater-surface water system. Considering mean travel times from each model cell to the coast, and disregarding travel times in the deep bedrock domain itself (which may be added to the here presented values), results show that travel times in scenario (II) were less than 4 years in 90% of the considered model area. Travel times were longer in scenario (I) with values higher than 10 years in 40% of the catchment area. These results are based on the assumption that the pathways do not go through zones of near-stagnant groundwater. If they would do so (and the above assumption is violated), results show that travel times can be considerably longer, for instance exceeding 400 years in half of the model area in scenario (I). Considering possible solute attenuation (caused by e.g. biogeochemical reactions or decay) along the hydrological transport pathways to inland surface waters and to the coast, we estimate solute mass delivery factors, representing the

Preliminary site description Forsmark area - version 1.2

Energy Technology Data Exchange (ETDEWEB)

Skagius, Kristina [ed.

2005-06-01

The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterisation at two different locations, the Forsmark and Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. An integrated component in the characterisation work is the development of a site descriptive model that constitutes a description of the site and its regional setting, covering the current state of the geosphere and the biosphere as well as those ongoing natural processes that affect their long-term evolution. The present report documents the site descriptive modelling activities (version 1.2) for the Forsmark area. The overall objectives of the version 1.2 site descriptive modelling are to produce and document an integrated description of the site and its regional environments based on the site-specific data available from the initial site investigations and to give recommendations on continued investigations. The modelling work is based on primary data, i.e. quality-assured, geoscientific and ecological field data available in the SKB databases SICADA and GIS, available July 31, 2004. The work has been conducted by a project group and associated discipline-specific working groups. The members of the project group represent the disciplines of geology, rock mechanics, thermal properties, hydrogeology, hydrogeochemistry, transport properties and surface ecosystems (including overburden, surface hydrogeochemistry and hydrology). In addition, some group members have specific qualifications of importance in this type of project e.g. expertise in RVS (Rock Visualisation System) modelling, GIS-modelling and in statistical data analysis. The overall strategy to achieve a site description is to develop discipline-specific models by interpretation and analyses of the primary data. The different discipline-specific models are then integrated into a site description. Methodologies for developing the discipline-specific models are documented in

Preliminary site description Forsmark area - version 1.2

International Nuclear Information System (INIS)

Skagius, Kristina

2005-06-01

The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterisation at two different locations, the Forsmark and Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. An integrated component in the characterisation work is the development of a site descriptive model that constitutes a description of the site and its regional setting, covering the current state of the geosphere and the biosphere as well as those ongoing natural processes that affect their long-term evolution. The present report documents the site descriptive modelling activities (version 1.2) for the Forsmark area. The overall objectives of the version 1.2 site descriptive modelling are to produce and document an integrated description of the site and its regional environments based on the site-specific data available from the initial site investigations and to give recommendations on continued investigations. The modelling work is based on primary data, i.e. quality-assured, geoscientific and ecological field data available in the SKB databases SICADA and GIS, available July 31, 2004. The work has been conducted by a project group and associated discipline-specific working groups. The members of the project group represent the disciplines of geology, rock mechanics, thermal properties, hydrogeology, hydrogeochemistry, transport properties and surface ecosystems (including overburden, surface hydrogeochemistry and hydrology). In addition, some group members have specific qualifications of importance in this type of project e.g. expertise in RVS (Rock Visualisation System) modelling, GIS-modelling and in statistical data analysis. The overall strategy to achieve a site description is to develop discipline-specific models by interpretation and analyses of the primary data. The different discipline-specific models are then integrated into a site description. Methodologies for developing the discipline-specific models are documented in

Preliminary site description Forsmark area - version 1.1

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-03-01

, mechanical classification by depth at KFM01A and at outcrops. A first model of thermal properties of the rock has been developed, although still rather immature due to few site-specific data in support of the model. The hydrogeological description is based on the new geological (structure) model and the fracture transmissivity distribution of the DFN model is based on the data from depth (cored borehole KFM01A). The fracture intensity and permeability are very low below 400 m depth. Hydrogeological simulations of the groundwater evolution since the last glaciation have been performed and compared with the hydrogeochemical conceptual model. The conceptual model of the development of post-glacial hydro geochemistry has been updated. Also, the salinity distribution, mixing processes and the major reactions altering the groundwaters have been described down to a depth of 200 m. A first model of the transport properties of the rock has been presented, although still rather immature due to lack of site-specific data in support of the model. For the near-surface, there is additional information regarding the stratigraphic distribution of glacial till and water-laid sediment, with related updates in the description. There is much uncertainty in version 1.1 of the site descriptive model, but the main uncertainties have been identified, some are also quantified and others are left as input to alternative hypotheses. However, since a main reason for uncertainty in version 1.1 is lack of data and poor data density and as much more data are expected in coming data freezes, it has not been judged meaningful to carry the uncertainty quantification or the alternative model generation too far. Advances have been made on some of the important site specific questions that were formulated in planning the execution programme for the Forsmark area. Concerning the shape of the tectonic lens, the understanding of the three dimensional shape of the rock domains in the local model area is now fair

Solute transport in coupled inland-coastal water systems. General conceptualisation and application to Forsmark

Energy Technology Data Exchange (ETDEWEB)

Jarsjoe, Jerker; Destouni, Georgia; Persson, Klas; Prieto, Carmen (Dept. of Physical Geography, Quaternary Geology, Stockholm Univ., Stockholm (Sweden))

2007-12-15

diffuse and occurring through SGD, small transient streams and/or coastal wetlands. Regarding transport quantifications, hydrogeochemical characteristics and pollution source loads may generally differ between larger, monitored catchments and smaller unmonitored coastal catchments. Since national hydrological monitoring data systematically exclude smaller, coastal catchments, they may not be representative for conditions in Forsmark (or Laxemar-Simpevarp). This emphasises the importance of extending in time the recently started hydrological and hydrogeochemical data series in the Forsmark and Laxemar-Simpevarp coastal catchment areas, since they are in effect unmonitored from a hydrological viewpoint, due to the lack of extended discharge time series. In the performed initial demonstration analysis of solute transport pathways from deep groundwater to recipients at the surface, we considered the main scenarios: (I) transport in the Quaternary deposits-bedrock interface zone only, and (II) transport in the coupled groundwater-surface water system. Considering mean travel times from each model cell to the coast, and disregarding travel times in the deep bedrock domain itself (which may be added to the here presented values), results show that travel times in scenario (II) were less than 4 years in 90% of the considered model area. Travel times were longer in scenario (I) with values higher than 10 years in 40% of the catchment area. These results are based on the assumption that the pathways do not go through zones of near-stagnant groundwater. If they would do so (and the above assumption is violated), results show that travel times can be considerably longer, for instance exceeding 400 years in half of the model area in scenario (I). Considering possible solute attenuation (caused by e.g. biogeochemical reactions or decay) along the hydrological transport pathways to inland surface waters and to the coast, we estimate solute mass delivery factors, representing the

Monitoring Forsmark - Bird monitoring in Forsmark 2012

Energy Technology Data Exchange (ETDEWEB)

Green, Martin [Dept of Biology, Lund Univ., Lund (Sweden)

2013-03-15

This report summarizes the monitoring of selected listed (Swedish Red List and/or the EU Birds directive) breeding birds in Forsmark 2002 - 2012. Monitoring of eleven listed species was conducted in the regional model area, including the candidate area in 2012 in the same way as in earlier years. The results from 2012 generally follow patterns recorded in earlier years. 2012 was in general a better bird year compared to 2010 and 2011 and most species (82%) showed increasing or stable numbers from 2011 to 2012. Only two species (18%) decreased in numbers between the last two years. All in all, six species (55 %, black-throated diver, honey buzzard, black grouse, ural owl, wryneck and red-backed shrike) show no significant trends since the start of the bird monitoring (2002/2003/2004 depending on species). During this period three species (27 %, white-tailed eagle, osprey and lesser spotted woodpecker) have increased in numbers while just two (18 %, capercaillie and hazelhen) have decreased. A new pair of black-throated divers was discovered in 2012 and seven resident pairs were registered. Breeding success was very good, the second best during the study period. Population development follows the national pattern, but breeding success seems to be better in Forsmark than in the country as a whole. Honey buzzards and ospreys occurred in good numbers, and breeding success for ospreys was good. No signs of successful breedings of honey buzzards were recorded, but this may mean little as no detailed monitoring of breeding success is made for this species. The white-tailed eagles had their best breeding year since the start of the SKB bird monitoring, meaning that during the last two years local breeding success has been back at the level recorded before the site investigations started. The three grouse species (black grouse, capercaillie and hazelhen) again showed somewhat varying patterns between the last two years as well as in the long run. The black grouse increased

Monitoring Forsmark-Bird monitoring in Forsmark 2012

International Nuclear Information System (INIS)

Green, Martin

2013-03-01

This report summarizes the monitoring of selected listed (Swedish Red List and/or the EU Birds directive) breeding birds in Forsmark 2002 - 2012. Monitoring of eleven listed species was conducted in the regional model area, including the candidate area in 2012 in the same way as in earlier years. The results from 2012 generally follow patterns recorded in earlier years. 2012 was in general a better bird year compared to 2010 and 2011 and most species (82%) showed increasing or stable numbers from 2011 to 2012. Only two species (18%) decreased in numbers between the last two years. All in all, six species (55 %, black-throated diver, honey buzzard, black grouse, ural owl, wryneck and red-backed shrike) show no significant trends since the start of the bird monitoring (2002/2003/2004 depending on species). During this period three species (27 %, white-tailed eagle, osprey and lesser spotted woodpecker) have increased in numbers while just two (18 %, capercaillie and hazelhen) have decreased. A new pair of black-throated divers was discovered in 2012 and seven resident pairs were registered. Breeding success was very good, the second best during the study period. Population development follows the national pattern, but breeding success seems to be better in Forsmark than in the country as a whole. Honey buzzards and ospreys occurred in good numbers, and breeding success for ospreys was good. No signs of successful breedings of honey buzzards were recorded, but this may mean little as no detailed monitoring of breeding success is made for this species. The white-tailed eagles had their best breeding year since the start of the SKB bird monitoring, meaning that during the last two years local breeding success has been back at the level recorded before the site investigations started. The three grouse species (black grouse, capercaillie and hazelhen) again showed somewhat varying patterns between the last two years as well as in the long run. The black grouse increased

Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

2008-08-15

The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are one of the major driving forces for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise

Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

International Nuclear Information System (INIS)

Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia

2008-08-01

The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are one of the major driving forces for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise in

Case studies in organic contaminant hydrogeology

International Nuclear Information System (INIS)

Baker, J.A.

1989-01-01

The effective management of domestic solid waste and hazardous, toxic, and radioactive waste is a major problem in the area of environmental geology and water sciences throughout the world. A series of case studies is presented of organic contaminants from both solid and hazardous waste disposal facilities to provide examples of these problems. The facilities were investigated to determine risks and liabilities before acquisition, to determine the site hydrogeologic conditions for design of appropriate groundwater monitoring plans, and/or to determine the potential for groundwater contamination. The case studies are of disposal facilities located in glacial tills, carbonaceous weathered clay soils, weathered shale, limestone bedrock, dolomite bedrock, and alluvial and sedimentary deposits. The results of these studies and investigations show certain relationships in the distribution of organic pollutants to the different geologic and hydrogeologic characteristics of each facility. In each of the four case studies, all 129 priority pollutants were analyzed in private wells and/or monitoring wells. The 31 volatile organic compounds (VOCs) of the priority pollutant list were the majority of organic compounds detected. When VOCs are found in groundwater impacted by disposal facilities, they are present in groups and tend to be distributed in patterns based on their relative concentrations. It is rare to find only one or two VOCs from facilities where leakage has been detected. The ethylenes and ethanes appear to be more prevalent and mobile than aromatic VOCs. The aromatics are restricted primarily to leachates and wastes and in monitoring wells located adjacent to facilities. 2 refs., 15 figs

Bioturbation in different ecosystems at Forsmark and Oskarshamn

Energy Technology Data Exchange (ETDEWEB)

Persson, Tryggve; Lenoir, Lisette; Taylor, Astrid [Dept. of Ecology and Environmental Research, Swedish University or Agricultural Sciences, Uppsala (Sweden)

2007-01-15

The Swedish Nuclear Fuel and Waste Management Co (SKB) carries out extensive investigations on factors that can affect long-term storage of nuclear waste. Earthworms consume organic soil materials and when doing so they transport and mix mineral soil particles as well as litter and humus materials. Ants do not consume soil materials, but they collect and mix mineral soil particles and litter materials to construct their nests. This process of material displacement by earthworms and ants is called bioturbation and can be a mechanism for the redistribution (vertical and horizontal) of radionuclides within the soil profile. The aim of the present study was to determine the quantitative impact of earthworms and ants on bioturbation of soil in different ecosystems at Forsmark and Oskarshamn. Earthworms were sampled at four 20x20 cm{sup 2} sub-plots at each site and were determined, dried and weighed in the laboratory. Gut passage time and faeces production were determined in a laboratory experiment at constant temperature. Temperature dependence of earthworm growth was studied at 3, 6, 10 and 20 deg C, and it was assumed that defecation mirrored growth as regards temperature dependence. Ant species composition, ant nest density and nest volume were investigated in the field by using pitfall traps and a transect method to enumerate ant nests. Dry weights of ant nests were determined after weighing in the laboratory. Earthworm abundances and biomasses were high in moist/wet alder forests and deciduous woodlands and low in pine and pine/spruce forests at both Forsmark and Oskarshamn. In mesic spruce forests, high estimates of abundance/biomass of earthworms were found at Forsmark but low at Oskarshamn, whereas grazed pastures had high estimates at Oskarshamn and ungrazed abandoned fields had relatively low estimates at Forsmark. High pH at Forsmark and low pH at Oskarshamn as well as high groundwater tables at some of the Forsmark sites can explain the difference between

Bioturbation in different ecosystems at Forsmark and Oskarshamn

International Nuclear Information System (INIS)

Persson, Tryggve; Lenoir, Lisette; Taylor, Astrid

2007-01-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) carries out extensive investigations on factors that can affect long-term storage of nuclear waste. Earthworms consume organic soil materials and when doing so they transport and mix mineral soil particles as well as litter and humus materials. Ants do not consume soil materials, but they collect and mix mineral soil particles and litter materials to construct their nests. This process of material displacement by earthworms and ants is called bioturbation and can be a mechanism for the redistribution (vertical and horizontal) of radionuclides within the soil profile. The aim of the present study was to determine the quantitative impact of earthworms and ants on bioturbation of soil in different ecosystems at Forsmark and Oskarshamn. Earthworms were sampled at four 20x20 cm 2 sub-plots at each site and were determined, dried and weighed in the laboratory. Gut passage time and faeces production were determined in a laboratory experiment at constant temperature. Temperature dependence of earthworm growth was studied at 3, 6, 10 and 20 deg C, and it was assumed that defecation mirrored growth as regards temperature dependence. Ant species composition, ant nest density and nest volume were investigated in the field by using pitfall traps and a transect method to enumerate ant nests. Dry weights of ant nests were determined after weighing in the laboratory. Earthworm abundances and biomasses were high in moist/wet alder forests and deciduous woodlands and low in pine and pine/spruce forests at both Forsmark and Oskarshamn. In mesic spruce forests, high estimates of abundance/biomass of earthworms were found at Forsmark but low at Oskarshamn, whereas grazed pastures had high estimates at Oskarshamn and ungrazed abandoned fields had relatively low estimates at Forsmark. High pH at Forsmark and low pH at Oskarshamn as well as high groundwater tables at some of the Forsmark sites can explain the difference between

Repository for spent nuclear fuel. Plant description layout D - Forsmark; Slutfoervarsanlaeggning foer anvaent kaernbraensle. Anlaeggningsbeskrivning layout D - Forsmark

Energy Technology Data Exchange (ETDEWEB)

2010-07-15

This document describes the final repository for spent nuclear fuel, SFK, which is located at Forsmark, in Oesthammar. The bedrock at the site is part of a so-called tectonic lens, in which the rock composition is relatively homogeneous and less deformed than outside the lens. The bedrock consists mainly of granite with high quartz content and good thermal conductivity. The central parts above ground are grouped in an operations area, located at the Soederviken on the south side of the intake duct for cooling water for nuclear power plant. Operating area is divided into an internal, secured portion, where the canisters of fuel are handled and there are links to the underground part, and a outer part, where the buffer, backfill and sealing used in the repository's barriers are produced. The above-ground part of the plant and also include storage of excavated rock, ventilation stations, and supplies of bentonite. The underground portion consists of a central area and a storage area. Caverns of the central area contain features for the underground operation. It communicates with the internal operating range above ground via a spiral ramp and several shafts. The ramp used to transport capsules of spent fuel and other heavy or bulky transport. The shafts are used to transport rock, buffer, backfill and staff, as well as for ventilation. The largest part of the space below ground is the repository where the canisters with the spent fuel are disposed. The capsules are deposited in vertical holes in the tunnels. When the deposit in a tunnel is complete, the tunnel is re-filled. The two main activities underground is rock work and disposal work, which are conducted separately from each other. Rock works covers all steps required to excavate tunnels and drill deposition holes, as well as to make temporary installations in the tunnels. To the landfill works count, besides the deposit of the capsule, the placement of the bentonite buffer in the deposition hole and

Hydrogeology of the Potsdam Sandstone in northern New York

Science.gov (United States)

Williams, John H.; Reynolds, Richard J.; Franzi, David A.; Romanowicz, Edwin A.; Paillet, Frederick L.

2010-01-01

The Potsdam Sandstone of Cambrian age forms a transboundary aquifer that extends across northern New York and into southern Quebec. The Potsdam Sandstone is a gently dipping sequence of arkose, subarkose, and orthoquartzite that unconformably overlies Precambrian metamorphic bedrock. The Potsdam irregularly grades upward over a thickness of 450 m from a heterogeneous feldspathic and argillaceous rock to a homogeneous, quartz-rich and matrix-poor rock. The hydrogeological framework of the Potsdam Sandstone was investigated through an analysis of records from 1,500 wells and geophysical logs from 40 wells, and through compilation of GIS coverages of bedrock and surficial geology, examination of bedrock cores, and construction of hydrogeological sections. The upper several metres of the sandstone typically is weathered and fractured and, where saturated, readily transmits groundwater. Bedding-related fractures in the sandstone commonly form sub-horizontal flow zones of relatively high transmissivity. The vertical distribution of sub-horizontal flow zones is variable; spacings of less than 10 m are common. Transmissivity of individual flow zones may be more than 100 m2/d but typically is less than 10 m2/d. High angle fractures, including joints and faults, locally provide vertical hydraulic connection between flow zones. Hydraulic head gradients in the aquifer commonly are downward; a laterally extensive series of sub-horizontal flow zones serve as drains for the groundwater flow system. Vertical hydraulic head differences between shallow and deep flow zones range from 1 m to more than 20 m. The maximum head differences are in recharge areas upgradient from the area where the Chateauguay and Chazy Rivers, and their tributaries, have cut into till and bedrock. Till overlies the sandstone in much of the study area; its thickness is generally greatest in the western part, where it may exceed 50 m. A discontinuous belt of bedrock pavements stripped of glacial drift extends

Construction experiences from underground works at Forsmark. Compilation Report

Energy Technology Data Exchange (ETDEWEB)

Carlsson, Anders [Vattenfall Power Consultant AB, Stockholm (Sweden); Christiansson, Rolf [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

2007-02-15

The main objective with this report, the Construction Experience Compilation Report (CECR), is to compile experiences from the underground works carried out at Forsmark, primarily construction experiences from the tunnelling of the two cooling water tunnels of the Forsmark nuclear power units 1, 2 and 3, and from the underground excavations of the undersea repository for low and intermediate reactor waste, SFR. In addition, a brief account is given of the operational experience of the SFR on primarily rock support solutions. The authors of this report have separately participated throughout the entire construction periods of the Forsmark units and the SFR in the capacity of engineering geologists performing geotechnical mapping of the underground excavations and acted as advisors on tunnel support; Anders Carlsson participated in the construction works of the cooling water tunnels and the open cut excavations for Forsmark 1, 2 and 3 (geotechnical mapping) and the Forsmark 3 tunnel (advise on tunnel support). Rolf Christiansson participated in the underground works for the SFR (geotechnical mapping, principal investigator for various measurements and advise on tunnel support and grouting). The report is to a great extent based on earlier published material as presented in the list of references. But it stands to reason that, during the course of the work with this report, unpublished notes, diaries, drawings, photos and personal recollections of the two authors have been utilised in order to obtain such a complete compilation of the construction experiences as possible.

Construction experiences from underground works at Forsmark. Compilation Report

International Nuclear Information System (INIS)

Carlsson, Anders; Christiansson, Rolf

2007-02-01

The main objective with this report, the Construction Experience Compilation Report (CECR), is to compile experiences from the underground works carried out at Forsmark, primarily construction experiences from the tunnelling of the two cooling water tunnels of the Forsmark nuclear power units 1, 2 and 3, and from the underground excavations of the undersea repository for low and intermediate reactor waste, SFR. In addition, a brief account is given of the operational experience of the SFR on primarily rock support solutions. The authors of this report have separately participated throughout the entire construction periods of the Forsmark units and the SFR in the capacity of engineering geologists performing geotechnical mapping of the underground excavations and acted as advisors on tunnel support; Anders Carlsson participated in the construction works of the cooling water tunnels and the open cut excavations for Forsmark 1, 2 and 3 (geotechnical mapping) and the Forsmark 3 tunnel (advise on tunnel support). Rolf Christiansson participated in the underground works for the SFR (geotechnical mapping, principal investigator for various measurements and advise on tunnel support and grouting). The report is to a great extent based on earlier published material as presented in the list of references. But it stands to reason that, during the course of the work with this report, unpublished notes, diaries, drawings, photos and personal recollections of the two authors have been utilised in order to obtain such a complete compilation of the construction experiences as possible

Hydrophysical logging: A new wellbore technology for hydrogeologic and contaminant characterization of aquifers

International Nuclear Information System (INIS)

Pedler, W.H.; Williams, L.L.; Head, C.L.

1992-01-01

In the continuing search for improved groundwater characterization technologies, a new wellbore fluid logging method has recently been developed to provide accurate and cost effective hydrogeologic and contaminant characterization of bedrock aquifers. This new technique, termed hydrophysical logging, provides critical information for contaminated site characterization and water supply studies and, in addition, offers advantages compared to existing industry standards for aquifer characterization. Hydrophysical logging is based on measuring induced electrical conductivity changes in the fluid column of a wellbore by employing advanced downhole water quality instrumentation specifically developed for the dynamic borehole environment. Hydrophysical logging contemporaneously identifies the locations of water bearing intervals, the interval-specific inflow rate during pumping, and in-situ hydrochemistry of the formation waters associated with each producing interval. In addition, by employing a discrete point downhole fluid sampler during hydrophysical logging, this technique provides evaluation of contaminant concentrations and migration of contaminants vertically within the borehole. Recently, hydrophysical logging was applied in a deep bedrock wellbore at an industrial site in New Hampshire contaminated with dense nonaqueous phase liquids (DNAPLs). The results of the hydrophysical logging, conducted as part of a hydrogeologic site investigation and feasibility study, facilitated investigation of the site by providing information which indicated that the contamination had not penetrated into deeper bedrock fractures at concentrations of concern. This information was used to focus the pending Remedial Action Plan and to provide a more cost-effective remedial design

Subsidence analysis Forsmark nuclear power plant - unit 1; Saettningsanalys Forsmarks kaernkraftverk - aggregat 1

Energy Technology Data Exchange (ETDEWEB)

Bono, Nancy; Fredriksson, Anders; Maersk Hansen, Lars (Golder Associates AB (Sweden))

2010-12-15

On behalf of SKB, Golder Associates Ltd carried out a risk analysis of subsidence during Forsmark nuclear power plant in the construction of the final repository for spent nuclear fuel near and below existing reactors. Specifically, the effect of horizontal cracks have been studied.

Safety-related site characteristics - a relative comparison of the Forsmark reference areas

International Nuclear Information System (INIS)

Winberg, Anders

2010-12-01

SKB has over the years from 2002 to 2008 conducted site investigations in Forsmark and Laxemar, with associated site modeling, design and safety analysis. In mid-2009 Forsmark was selected on the basis of analysis made as site for a future repository for spent nuclear fuel. Based on defined safety-related geoscientific location factors data from Forsmark are compared in relative terms with data from a number of locations in Sweden, previously studied by SKB. The factors compared include: the rock's composition and structures, future climate evolution, rock mechanical conditions, earthquakes, groundwater flow, groundwater composition, delay of solutes, and the ability to characterize and describe the location. Past comparisons of these properties for the selected sites show that none of these sites collectively show any significant benefit over Forsmark site for a repository. This does not preclude that there may be places on the basis of an overall assessment of geoscientific location factors could be equivalent to Forsmark

Bedrock geologic map of the Nashua South quadrangle, Hillsborough County, New Hampshire, and Middlesex County, Massachusetts

Science.gov (United States)

Walsh, Gregory J.; Jahns, Richard H.; Aleinikoff, John N.

2013-01-01

The bedrock geology of the 7.5-minute Nashua South quadrangle consists primarily of deformed Silurian metasedimentary rocks of the Berwick Formation. The metasedimentary rocks are intruded by a Late Silurian to Early Devonian diorite-gabbro suite, Devonian rocks of the Ayer Granodiorite, Devonian granitic rocks of the New Hampshire Plutonic Suite including pegmatite and the Chelmsford Granite, and Jurassic diabase dikes. The bedrock geology was mapped to study the tectonic history of the area and to provide a framework for ongoing hydrogeologic characterization of the fractured bedrock of Massachusetts and New Hampshire. This report presents mapping by G.J. Walsh and R.H. Jahns and zircon U-Pb geochronology by J.N. Aleinikoff. The complete report consists of a map, text pamphlet, and GIS database. The map and text pamphlet are only available as downloadable files (see frame at right). The GIS database is available for download in ESRITM shapefile and Google EarthTM formats, and includes contacts of bedrock geologic units, faults, outcrops, structural geologic information, photographs, and a three-dimensional model.

Market led: Forsmark looks to 2000

International Nuclear Information System (INIS)

Anon.

1994-01-01

The Forsmark nuclear power plant in Sweden includes three BWR reactors totalling 3200 MWe. From a design level of 70% the average capability factor has been increased to 90%. This has been achieved by a market-orientated approach with efficient outages and a total production cost identified with each unit in order to show how each stands in relation to the market price level and to outside competition. Forsmark's performance, as indicated by capacity factors, refuelling outage length and electricity production costs is better than most. Strategic planning is important and a refurbishment programme up to 2000 is planned to renew the electricity generators, replace the process computers and upgrade the preheater systems. (UK)

Safety improvement plant modifications at Forsmark 3, 1986-1995

Energy Technology Data Exchange (ETDEWEB)

Kjellander, M. [Kaernkraftsaekerhet och utbildning, Nykoeping (Sweden)

1998-10-01

All important plant modifications implemented in safety-related equipment or software at Forsmark 3 are compiled in this report. The report covers the period from the start of commercial operation in 1985 up to and including 1995. The plant modifications, which were carried out by different suppliers during the guarantee period, are not included in the report since they have not been administered by the Forsmark organisation. The report contains references to relevant modification notices and to files and file divider numbers. These data refer to the Safety Department central archives. The report is based on Forsmark 3 Technical Specifications (STF) which means that Chapter 3 is divided into the same sections as in the STF. Modifications, which cannot be directly attributed to any specific STF chapter, and major modifications are described separately

Sensitivity analysis and development of calibration methodology for near-surface hydrogeology model of Forsmark

International Nuclear Information System (INIS)

Aneljung, Maria; Gustafsson, Lars-Goeran

2007-04-01

The hydrological modelling system MIKE SHE has been used to describe near-surface groundwater flow, transport mechanisms and the contact between ground- and surface water at the Forsmark site. The surface water system at Forsmark is described with the 1D modelling tool MIKE 11, which is fully and dynamically integrated with MIKE SHE. In spring 2007, a new data freeze will be available and a process of updating, rebuilding and calibrating the MIKE SHE model will start, based on the latest data set. Prior to this, it is important to gather as much knowledge as possible on calibration methods and to define critical calibration parameters and areas within the model. In this project, an optimization of the numerical description and an initial calibration of the MIKE SHE model has been made, and an updated base case has been defined. Data from 5 surface water level monitoring stations, 4 surface water discharge monitoring stations and 32 groundwater level monitoring stations (SFM soil boreholes) has been used for model calibration and evaluation. The base case simulations generally show a good agreement between calculated and measured water levels and discharges, indicating that the total runoff from the area is well described by the model. Moreover, with two exceptions (SFM0012 and SFM0022) the base case results show very good agreement between calculated and measured groundwater head elevations for boreholes installed below lakes. The model also shows a reasonably good agreement between calculated and measured groundwater head elevations or depths to phreatic surfaces in many other points. The following major types of calculation-measurement differences can be noted: Differences in groundwater level amplitudes due to transpiration processes. Differences in absolute mean groundwater head, due to differences between borehole casing levels and the interpolated DEM. Differences in absolute mean head elevations, due to local errors in hydraulic conductivity values

Sensitivity analysis and development of calibration methodology for near-surface hydrogeology model of Forsmark

Energy Technology Data Exchange (ETDEWEB)

Aneljung, Maria; Gustafsson, Lars-Goeran [DHI Water and Environment AB, Goeteborg (Sweden)

2007-04-15

The hydrological modelling system MIKE SHE has been used to describe near-surface groundwater flow, transport mechanisms and the contact between ground- and surface water at the Forsmark site. The surface water system at Forsmark is described with the 1D modelling tool MIKE 11, which is fully and dynamically integrated with MIKE SHE. In spring 2007, a new data freeze will be available and a process of updating, rebuilding and calibrating the MIKE SHE model will start, based on the latest data set. Prior to this, it is important to gather as much knowledge as possible on calibration methods and to define critical calibration parameters and areas within the model. In this project, an optimization of the numerical description and an initial calibration of the MIKE SHE model has been made, and an updated base case has been defined. Data from 5 surface water level monitoring stations, 4 surface water discharge monitoring stations and 32 groundwater level monitoring stations (SFM soil boreholes) has been used for model calibration and evaluation. The base case simulations generally show a good agreement between calculated and measured water levels and discharges, indicating that the total runoff from the area is well described by the model. Moreover, with two exceptions (SFM0012 and SFM0022) the base case results show very good agreement between calculated and measured groundwater head elevations for boreholes installed below lakes. The model also shows a reasonably good agreement between calculated and measured groundwater head elevations or depths to phreatic surfaces in many other points. The following major types of calculation-measurement differences can be noted: Differences in groundwater level amplitudes due to transpiration processes. Differences in absolute mean groundwater head, due to differences between borehole casing levels and the interpolated DEM. Differences in absolute mean head elevations, due to local errors in hydraulic conductivity values

The relationship between hydrogeologic properties and sedimentary facies: an example from Pennsylvanian bedrock aquifers, southwestern Indiana

International Nuclear Information System (INIS)

Fisher, A.T.; Barnhill, M.; Revenaugh, J.

1998-01-01

The relationship between the hydrogeologic properties and sedimentary facies of shallow Pennsylvanian bedrock aquifers was examined using detailed sedimentologic descriptions, aquifer (slug) tests, and gamma ray logs. The main goal of the study was to determine if it was possible to reliably estimate near-well hydraulic conductivities using core descriptions and logging data at a complex field site, based on assignment of consistent conductivity indicators to individual facies. Lithologic information was gathered from three sources: core descriptions, simplified lithologic columns derived from the core descriptions, and drillers' logs. Gamma ray data were collected with a conventional logging instrument. Slug tests were conducted in all wells containing screened zones entirely within the Pennsylvanian facies of interest. Simplified subsets of sedimentologic facies were assembled for classification of subsurface geology, and all rocks within the screened intervals of test wells were assigned to individual facies based on visual descriptions. Slug tests were conducted to determine the bulk hydraulic conductivity (a spatial average within the screened interval) in the immediate vicinity of the wells, with measured values varying from 10 -4 m/s to 10 -8 m/s. Gamma ray logs from these wells revealed variations in raw counts above about 1.5 orders of magnitude. Data were combined using simple linear and nonlinear inverse techniques to derive relations between sedimentologic facies, gamma ray signals, and bulk hydraulic conductivities. The analyses suggest that facies data alone, even those derived from detailed core descriptions, are insufficient for estimating hydraulic conductivity in this setting to better than an order of magnitude. The addition of gamma ray data improved the estimates, as did selective filtering of several extreme values from the full data set. Better estimates might be obtained through more careful field measurements and reduction of

Uncertainty aspects of the digital elevation model for the Forsmark area

Energy Technology Data Exchange (ETDEWEB)

Stroemgren, Maarten; Brydsten, Lars (Umeaa Univ., Umeaa (Sweden))

2009-10-15

A digital elevation model (DEM) describes the terrain relief. A proper DEM is an important data source for many of the different site description models conducted in the Forsmark region. Input data for the Forsmark DEM is elevation data for both land and sea areas of different origin and quality. No statistical analysis of the error in the Forsmark DEM is so far carried out. However, the Forsmark DEM is part of the quality assessment of the regolith depth model for the Forsmark area since it represents the upper surface of the regolith depth model. The aim of this project was to calculate the errors in different areas in the Forsmark DEM and present them in terms of general descriptive statistics. Measurements have confirmed the knowledge that the 0.25-metre DEM produced from the laser scanning measurements in the Laxemar-Simpevarp area is of very high quality. The 0.25-metre DEM was used to calculate the errors of the 10 and 50-metre DEMs, and the errors for different sea shoreline sources. These error distributions were placed randomly among points for the same data sources in the Forsmark area and used for correction of the original elevation levels. Using the corrected input data for the 10 and 50-metre DEMs and for the sea shoreline, a new DEM was produced. All other input data remained unchanged. The error for the Forsmark DEM was calculated for areas within the data sources corrected from the 0.25-metre DEM. The 0.25-metre DEM from the Laxemar-Simpevarp area was also used for a calculation of how density of input data points used in interpolation affects quality in a 20-metre DEM. Part of the input data was removed in the sea area, new DEMs were produced and compared to the existing Forsmark DEM within the areas of the removed data, to get a measure of the error in these areas of the DEM. In areas of input data for the sea shoreline, the quality of the Forsmark DEM is high. The errors within the SKB 10-metre DEM are slightly less than within the extension

Uncertainty aspects of the digital elevation model for the Forsmark area

International Nuclear Information System (INIS)

Stroemgren, Maarten; Brydsten, Lars

2009-10-01

A digital elevation model (DEM) describes the terrain relief. A proper DEM is an important data source for many of the different site description models conducted in the Forsmark region. Input data for the Forsmark DEM is elevation data for both land and sea areas of different origin and quality. No statistical analysis of the error in the Forsmark DEM is so far carried out. However, the Forsmark DEM is part of the quality assessment of the regolith depth model for the Forsmark area since it represents the upper surface of the regolith depth model. The aim of this project was to calculate the errors in different areas in the Forsmark DEM and present them in terms of general descriptive statistics. Measurements have confirmed the knowledge that the 0.25-metre DEM produced from the laser scanning measurements in the Laxemar-Simpevarp area is of very high quality. The 0.25-metre DEM was used to calculate the errors of the 10 and 50-metre DEMs, and the errors for different sea shoreline sources. These error distributions were placed randomly among points for the same data sources in the Forsmark area and used for correction of the original elevation levels. Using the corrected input data for the 10 and 50-metre DEMs and for the sea shoreline, a new DEM was produced. All other input data remained unchanged. The error for the Forsmark DEM was calculated for areas within the data sources corrected from the 0.25-metre DEM. The 0.25-metre DEM from the Laxemar-Simpevarp area was also used for a calculation of how density of input data points used in interpolation affects quality in a 20-metre DEM. Part of the input data was removed in the sea area, new DEMs were produced and compared to the existing Forsmark DEM within the areas of the removed data, to get a measure of the error in these areas of the DEM. In areas of input data for the sea shoreline, the quality of the Forsmark DEM is high. The errors within the SKB 10-metre DEM are slightly less than within the extension

Forsmark 1

International Nuclear Information System (INIS)

Fredell, J.; Henriksson, T.

1981-12-01

ASEA-ATOM carried out an experiment in Forsmark 1 in 1978, in conjunction with discharge test, by means of the safety/relief valves. The tests have been carried out for the case of single valve actuation (SVA), multiple valve actuations (MVA) and consecutive valve actuations (CVA). During MVA tests, up to 12 valves have been used. One of the aims of the experiment was to confirm the operation of the new design of mitigator of the discharge pipes and another was to survey the pressure oscillations in the pool and the vibratory behaviour of the structures and components. The results of these measurements are presented in a number of reports. This report contains an abstract of the results of the measurements presented in these reports. This report also describes the theoretical background and comparisons between test and theoretical results. It is clear that very good agreement has been established between earlier steam discharge experiments, using a mitigator of the type fitted in Forsmark 1, and this experiment. This is based on the fact the amplitude, frequency and distribution of the pressure oscillations in the condensation pool are basically equal to the values predicted by calculations based on the earlier experiments. The low maximum acceleration amplitudes predicted by the beam type structural model have been confirmed, but the frequency content of the response is not very well represented by this type of model. The shell-beam finite element model of the structure gives better agreement with the measured frequency. (author)

Comparison of the behaviour of rare earth elements in surface waters, overburden groundwaters and bedrock groundwaters in two granitoidic settings, Eastern Sweden

International Nuclear Information System (INIS)

Roennback, Pernilla; Astroem, Mats; Gustafsson, Jon-Petter

2008-01-01

This work, which was done within the Swedish nuclear waste management program, was carried out in order to increase the understanding of the mobility and fate of rare earth elements (REEs) in natural boreal waters in granitoidic terrain. Two areas were studied, Forsmark and Simpevarp, one of which will be selected as a site for spent nuclear fuel. The highest REE concentrations were found in the overburden groundwaters, in Simpevarp in particular (median ΣREE 52 μg/L), but also in Forsmark (median ΣREE 6.7 μg/L). The fractionation patterns in these waters were characterised by light REE (LREE) enrichment and negative Ce and Eu anomalies. In contrast, the surface waters had relatively low REE concentrations. They were characterised either by an increase in relative concentrations throughout the lanthanide series (Forsmark which has a carbonate-rich till) or flat patterns (Simpevarp with carbonate-poor till), and had negative Ce and Eu anomalies. In the bedrock groundwaters, the concentrations and fractionation patterns of REEs were entirely different from those in the overburden groundwaters. The median La concentrations were low (just above 0.1 μg/L in both areas), only in a few samples were the concentrations of several REEs (and in a couple of rare cases all REEs) above the detection limit, and there was an increase in the relative concentrations throughout the lanthanide series. In contrast to these large spatial variations, the temporal trends were characterised by small (or non existent) variations in REE-fractionation patterns but rather large variations in concentrations. The Visual MINTEQ speciation calculations predicted that all REEs in all waters were closely associated with dissolved organic matter, and not with carbonate. In the hydrochemical data for the overburden groundwater in particular, there was however a strong indication of association with inorganic colloids, which were not included in the speciation model. Overall the results showed

Preliminary site description Forsmark area - version 1.1

International Nuclear Information System (INIS)

2004-03-01

, mechanical classification by depth at KFM01A and at outcrops. A first model of thermal properties of the rock has been developed, although still rather immature due to few site-specific data in support of the model. The hydrogeological description is based on the new geological (structure) model and the fracture transmissivity distribution of the DFN model is based on the data from depth (cored borehole KFM01A). The fracture intensity and permeability are very low below 400 m depth. Hydrogeological simulations of the groundwater evolution since the last glaciation have been performed and compared with the hydrogeochemical conceptual model. The conceptual model of the development of post-glacial hydro geochemistry has been updated. Also, the salinity distribution, mixing processes and the major reactions altering the groundwaters have been described down to a depth of 200 m. A first model of the transport properties of the rock has been presented, although still rather immature due to lack of site-specific data in support of the model. For the near-surface, there is additional information regarding the stratigraphic distribution of glacial till and water-laid sediment, with related updates in the description. There is much uncertainty in version 1.1 of the site descriptive model, but the main uncertainties have been identified, some are also quantified and others are left as input to alternative hypotheses. However, since a main reason for uncertainty in version 1.1 is lack of data and poor data density and as much more data are expected in coming data freezes, it has not been judged meaningful to carry the uncertainty quantification or the alternative model generation too far. Advances have been made on some of the important site specific questions that were formulated in planning the execution programme for the Forsmark area. Concerning the shape of the tectonic lens, the understanding of the three dimensional shape of the rock domains in the local model area is now fair

The marine ecosystems at Forsmark and Laxemar-Simpevarp. SR-Site Biosphere

Energy Technology Data Exchange (ETDEWEB)

Aquilonius, Karin [ed.; Studsvik Nuclear AB (Sweden)

2010-12-15

The overall objective of this report is to provide a thorough description of the marine ecosystems at the sites Forsmark and Laxemar-Simpevarp, to identify processes in these ecosystems of importance to transfer and accumulation of radionuclides and, finally based on this knowledge, develop parameters to be used for the marine ecosystem in the safety analysis SR-Site. The report includes a thorough description of the major components in the marine ecosystems in Forsmark and Laxemar-Simpevarp, and covers the following areas: chemical and physical characteristics, climate and meteorology, morphology and regolith, biota in the marine ecosystem, human impact, water exchange and historical evolution at the sites. The site specific characteristics are compared with marine data from the Baltic region. Marine ecosystem modeling and mass balances calculations for carbon and a number of other elements were carried out to further improve the understanding of the marine ecosystems. Important processes for the safety assessment are identified, described and evaluated according to a systematic method. The derivation of marine ecosystem parameters and the resulting parameters is presented. The last chapter of the report aims at summarizing the knowledge of the marine ecosystems at the two areas. In comparison with the Gulf of Bothnia and the Baltic Proper, salinity is somewhat lower in Forsmark and Laxemar-Simpevarp respectively. The nitrogen and phosphorus levels at the two sites are low to moderately high compared with environmental monitoring data for corresponding areas in the Baltic Sea. In Forsmark, nitrogen seems to be the limiting nutrient during the summer months. In Laxemar-Simpevarp, nitrogen seems to be the limiting nutrient in the outer areas and phosphorus in the inner bays. This coincides with the general conditions in the Bothnian Sea (Forsmark) and the Baltic Proper (Laxemar-Simpevarp). The annual mean water temperature in Forsmark is slightly higher than the

The marine ecosystems at Forsmark and Laxemar-Simpevarp. SR-Site Biosphere

International Nuclear Information System (INIS)

Aquilonius, Karin

2010-12-01

The overall objective of this report is to provide a thorough description of the marine ecosystems at the sites Forsmark and Laxemar-Simpevarp, to identify processes in these ecosystems of importance to transfer and accumulation of radionuclides and, finally based on this knowledge, develop parameters to be used for the marine ecosystem in the safety analysis SR-Site. The report includes a thorough description of the major components in the marine ecosystems in Forsmark and Laxemar-Simpevarp, and covers the following areas: chemical and physical characteristics, climate and meteorology, morphology and regolith, biota in the marine ecosystem, human impact, water exchange and historical evolution at the sites. The site specific characteristics are compared with marine data from the Baltic region. Marine ecosystem modeling and mass balances calculations for carbon and a number of other elements were carried out to further improve the understanding of the marine ecosystems. Important processes for the safety assessment are identified, described and evaluated according to a systematic method. The derivation of marine ecosystem parameters and the resulting parameters is presented. The last chapter of the report aims at summarizing the knowledge of the marine ecosystems at the two areas. In comparison with the Gulf of Bothnia and the Baltic Proper, salinity is somewhat lower in Forsmark and Laxemar-Simpevarp respectively. The nitrogen and phosphorus levels at the two sites are low to moderately high compared with environmental monitoring data for corresponding areas in the Baltic Sea. In Forsmark, nitrogen seems to be the limiting nutrient during the summer months. In Laxemar-Simpevarp, nitrogen seems to be the limiting nutrient in the outer areas and phosphorus in the inner bays. This coincides with the general conditions in the Bothnian Sea (Forsmark) and the Baltic Proper (Laxemar-Simpevarp). The annual mean water temperature in Forsmark is slightly higher than the

Iowa Bedrock Geology

Data.gov (United States)

Iowa State University GIS Support and Research Facility — The bedrock geologic map portrays the current interpretation of the distribution of various bedrock stratigraphic units present at the bedrock surface. The bedrock...

Proposed approach for bedrock characterization at Chalk River Nuclear Laboratories for waste disposal

International Nuclear Information System (INIS)

Heystee, R.J.; Dixon, D.F.

1985-07-01

Low- and intermediate-level wastes (L AND ILW) are produced at the Chalk River Nuclear Laboratories (CRNL) by the operation of reactors for nuclear research and development and by the production of radioisotopes. CRNL also manages L and ILW produced by Canadian research laboratories, universities, hospitals and some industries. An option that is being considered for the disposal of some of these wastes is to emplace them in a shallow rock cavity in fractured crystalline bedrock on the CRNL property. To design such a disposal facility and to evalute its long-term performance, data must be obtained on the geologic and hydrogeologic characteristics of the site. Over the past several years, a variety of airborne, ground surface and borehole geological, geophysical and/or hydrogeological methods have been used to acquire data on some rock mass discontinuities at CRNL. The techniques which are apparently more useful for acquiring these data are described and a proposed approach to site characterization for a shallow rock cavity at CRNL is outlined

Environmental monitoring at the Forsmark nuclear power plant

International Nuclear Information System (INIS)

Sandstroem, O.

1991-01-01

The use of cooling water at such large power plants as Forsmark creates a considerable hazard for fish in the intake area, as they may be transported into the plant and killed. Several millions of Baltic herring and three-spined stickleback are lost each year at the intake screens. A release of cooling water to an open sea area is generally considered as a minor environmental problem, a presumption so far not contradicated by the results from the monitoring studies at Forsmark. In the Biotest basin, however, where the exposure to heat is maximal, a long series of effects ultimately changing populations of plants, benthic animals and fish have been documented. One important conclusion after ten years of studies in a heated Biotest basin, is that ecosystem stability seems to need very long time to be established, if it ever will. The monitoring of radioactivity controls the quality of the fish as food but is also directed to select special species accumulating these elements, bladder wrack etc. At Forsmark only small amounts of radionuclides from the plant so far have been detected in the marine environment. (KAE)

Monitoring Forsmark. Meteorological monitoring at Forsmark, January-December 2010

Energy Technology Data Exchange (ETDEWEB)

Andersson, Cari; Jones, Joergen (Swedish Meteorological and Hydrological Institute (SMHI), Norrkoeping (Sweden))

2011-01-15

In the Forsmark area, SKB's meteorological monitoring started in 2003 at the sites Storskaeret and Hoegmasten. However, since July 1, 2007 measurements are only performed at Hoegmasten. Measured and calculated parameters at Hoegmasten are precipitation and corrected precipitation, air temperature, barometric pressure, wind speed and direction, air humidity, global radiation and potential evapotranspiration. The Swedish Meteorological and Hydrological Institute, SMHI, has been responsible for planning and design, as well as for the operation of the stations used for meteorological monitoring. In general, the quality of the meteorological measurements during the period concerned, starting January 1, 2010, and ending December 31, 2010, has shown to be good

Hydrogeology of the Croton-Ossining area, Westchester County, New York

Science.gov (United States)

Reynolds, Richard J.

1988-01-01

The hydrogeology of a 29-sq-mi area surrounding the village of Croton-on-Hudson, New York, is summarized on 6 sheets at 1:12 ,000 scale that show locations of wells and test holes, surficial geology, geologic sections, bedrock geology, land use, and soil permeability. The primary stratified-drift aquifer in this area is the Croton River aquifer, which consists of outwash sand and gravel that partly fills the Croton River valley from the New Croton Dam to the Hudson River--a distance of approximately 3 miles. The valley is narrow and ranges in width from 100 to 1,900 ft, and its v-notch bedrock floor ranges from 30 to 50 ft below sea level. Detailed hydrogeologic studies during 1936-38 showed the stratigraphy to consist of an upper water-table aquifer with a saturated thickness of about 35 ft, underlain by a silt and clay confining unit 8 to o0 ft in thickness that in turn is underlain by a lower confined outwash aquifer up to 40 ft thick. Aquifer-test data and laboratory permeability tests show that the average hydraulic conductivity of the upper outwash aquifer is 475 ft/d, and that of the lower confined aquifer is about 300 ft/d. The aquifer is recharged through direct precipitation, runoff from adjacent hillsides, and leakage under the new Croton Dam. Previous studies estimate the average leakage under the dam to be 0.65 Mgal/d and the total average daily recharge to the aquifer between New Croton Dam and Quaker Bridge to be 1.73 Mgal/d. (USGS)

Man-machine communication at Forsmark 3

International Nuclear Information System (INIS)

Hultquist, Goeran; Norberg, Soeren

1984-01-01

The design of Forsmark 3 began in 1976 and the control room layout and equipment were discussed right from the start. Susequent evolution and events in other nuclear power plants have, however, radically changed the direction of the development of the man-machine functions. (author)

Lessons from the Forsmark 1 event in Sweden

International Nuclear Information System (INIS)

Jorle, A.

2007-01-01

A short circuit at a switchyard broke some of the safety chains in the reactor safety system and created a difficult situation in the control room at the Forsmark 1 power plant in Sweden. After a scram two of four diesel generators failed to deliver power but the reactor could safely be controlled through remaining two systems and power could be distributed from external grid after 22 minutes. Surveillance systems in the control room also failed and the situation at the reactor was unclear. Analysis shows that there was never a risk to the public and no damage on the core. The incident exposed unknown weakness in the power supply systems of the reactor. Also it was found that maintenance had failed and some components were not properly installed. The regulator identified the problem as a serious failure but did not at once realize the public impact. The licensee was late in its decision making and did only publish local press releases that did not fully expose the nature of the incident. After some days an independent expert claimed that a core melt was a close possibility. He was widely quoted and created a media impact many European countries. In the light of the incident problems with safety culture was identified at the plant and additional findings showed problems in the management system of Forsmark. Growing media interest culminated in January when a critical internal report from staff members in Forsmark was made public. Some lessons learnt: - Media activity followed well-known patterns. - The regulator was an important source for media. - Regulator not fired upon until January, after a long autumn filled with negative reporting on Forsmark. - The plant was not proactive in its communication which created a problem for the regulator. (author)

Nitrate distribution and potential attenuation mechanisms of a municipal water supply bedrock aquifer

International Nuclear Information System (INIS)

Opazo, Tomás; Aravena, Ramón; Parker, Beth

2016-01-01

The Silurian bedrock aquifer constitutes a major aquifer system for groundwater supply across the Ontario province in Canada. The application of natural and industrial fertilizers near urban centers has led to groundwater NO_3"−-N concentrations that sometimes have exceeded the drinking water limit, posing a threat to the usage of groundwater for the human consumption. Therefore, there is a growing interest and concern about how nitrate is being leached, transported and potentially attenuated in bedrock aquifers. This study assesses the local distribution of groundwater NO_3"− in the up-gradient area of two historically impacted municipal wells, called Carter Wells, in the City of Guelph, Canada, in order to evaluate the potential nitrate attenuation mechanisms, using both groundwater geochemical and isotopic analysis ("3H, δ"1"5N-NO_3, δ"1"8O-NO_3, δ"1"8O-SO_4, δ"3"4S-SO_4) and a detailed vertical hydrogeological and geochemical bedrock characterization. The results indicate that probably the main source of nitrate to the Carter Wells is the up-gradient Arkell Research Station (ARS), an agricultural research facility where manure has been historically applied. The overburden and bedrock groundwater with high NO_3 concentrations at the ARS exhibits a manure-related δ"1"5N and δ"1"8O signature, isotopically similar to the high nitrate in the down-gradient groundwater from domestic wells and from the Carter Wells. The nitrate spatial distribution appears to be influenced and controlled by the geology, in which more permeable rock is found in the Guelph Formation which in turn is related to most of the high NO_3"− groundwater. The presence of an underlying low permeability Eramosa Formation favors the development of oxygen-depleted conditions, a key factor for the occurrence of denitrification. Groundwater with low NO_3"−-N concentrations associated with more oxygen-limited conditions and coincident with high SO_4"2"− concentrations are related to more

Explorative analysis of major components and isotopes. SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Smellie, John (Conterra AB (Sweden)); Tullborg, Eva-Lena (Terralogica AB (Sweden)); Nilsson, Ann-Chatrin (Geosigma AB (Sweden)); Sandstroem, Bjoern (Goeteborg Univ. (Sweden)); Waber, Niklaus (Univ. of Bern (Switzerland)); Gimeno, Maria (Univ. of Zaragoza (Spain)); Gascoyne, Mel (GGP Inc. (United Kingdom))

2008-09-15

The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate events are the major driving force for hydrogeochemical changes and therefore are of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise in

Explorative analysis of major components and isotopes. SDM-Site Forsmark

International Nuclear Information System (INIS)

Smellie, John; Tullborg, Eva-Lena; Nilsson, Ann-Chatrin; Sandstroem, Bjoern; Waber, Niklaus; Gimeno, Maria; Gascoyne, Mel

2008-09-01

The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate events are the major driving force for hydrogeochemical changes and therefore are of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise in

SR-Site - sulphide content in the groundwater at Forsmark

Energy Technology Data Exchange (ETDEWEB)

Tullborg, E-L (Terralogica (Sweden)); Smellie, J (Conterra (Sweden)); Nilsson, A-Ch (Geosigma (Sweden)); Gimeno, M J; Auque, LF (Univ. of Zaragoza (Spain)); Bruchert, V (Stockholms Universitet (Sweden)); Molinero, J (Amphos21 (Spain))

2010-12-15

during the monitoring phase. When both CCC and monitoring values are available from one borehole section two values are used, one representing each of the sampling methods. When time series are measured in the monitoring sections, in most cases the sulphide values are higher in the downhole tubing and in the borehole section compared with groundwater from the surrounding fractures. The routinely carried out removal of five borehole section water volumes prior to monitoring are in most cases inadequate to obtain representative samples from the bedrock fractures, i.e. without elevated sulphide due to contamination from the initial stagnant water from the borehole section. It is, however, assumed that the two groundwater samples from the same water conducting structures, i.e. the sample from the monitoring and the sample from the CCC sampling, the latter usually showing lower sulphide, spans the interval of representative sulphide values in the formation water. For most of the CCC and monitoring sections the last sample in the time series is suggested as representing the 'best possible' value. It is worth noting that the plug flow calculations have proven to be very useful in order to judge the water volumes needed to be pumped at each monitored section before obtaining a sample sufficiently representative of the fracture groundwater. Practically all sulphide concentrations at Forsmark are <= 0.013 mmol/L (approx0.4 mg/L). There is, however, a probability that for some deposition location in the repository the surrounding groundwaters may have sulphide concentrations as high as 0.12 mmol/L (approx4 mg/L). In order to estimate canister corrosion rates in the SR-Site during a full glacial cycle, it is recommended that the observed distribution of sulphide in groundwaters at Forsmark during the present temperate conditions should be used. Furthermore, it should be noted that the present sulphide concentrations have been sampled after a recent period of possible

SR-Site - sulphide content in the groundwater at Forsmark

International Nuclear Information System (INIS)

Tullborg, E-L; Smellie, J; Nilsson, A-Ch; Gimeno, M J; Auque, LF; Bruchert, V; Molinero, J

2010-12-01

the monitoring phase. When both CCC and monitoring values are available from one borehole section two values are used, one representing each of the sampling methods. When time series are measured in the monitoring sections, in most cases the sulphide values are higher in the downhole tubing and in the borehole section compared with groundwater from the surrounding fractures. The routinely carried out removal of five borehole section water volumes prior to monitoring are in most cases inadequate to obtain representative samples from the bedrock fractures, i.e. without elevated sulphide due to contamination from the initial stagnant water from the borehole section. It is, however, assumed that the two groundwater samples from the same water conducting structures, i.e. the sample from the monitoring and the sample from the CCC sampling, the latter usually showing lower sulphide, spans the interval of representative sulphide values in the formation water. For most of the CCC and monitoring sections the last sample in the time series is suggested as representing the 'best possible' value. It is worth noting that the plug flow calculations have proven to be very useful in order to judge the water volumes needed to be pumped at each monitored section before obtaining a sample sufficiently representative of the fracture groundwater. Practically all sulphide concentrations at Forsmark are ≤ 0.013 mmol/L (∼0.4 mg/L). There is, however, a probability that for some deposition location in the repository the surrounding groundwaters may have sulphide concentrations as high as 0.12 mmol/L (∼4 mg/L). In order to estimate canister corrosion rates in the SR-Site during a full glacial cycle, it is recommended that the observed distribution of sulphide in groundwaters at Forsmark during the present temperate conditions should be used. Furthermore, it should be noted that the present sulphide concentrations have been sampled after a recent period of possible intrusion of marine

Water activities in Forsmark. Ecological field inventory and classification of biodiversity values and description of forest production land; Vattenverksamhet i Forsmark. Ekologisk faeltinventering och naturvaerdesklassificering samt beskrivning av skogsproduktionsmark

Energy Technology Data Exchange (ETDEWEB)

Hamren, Ulrika; Collinder, Per [Ekologigruppen AB (Sweden)

2010-12-15

In 2009, the Swedish Nuclear Fuel and Waste Management Co (SKB) chose Forsmark in the Municipality of Oesthammar as site for the final repository for spent nuclear fuel. This report describes nature values and forestry areas in Forsmark, and provides part of the background material for description of consequences due to groundwater diversion during construction and operation of the repository. The report describes results of map studies and comprehensive field investigations, in terms of geographical delineations, descriptions of characteristics and classifications of nature values for groundwater dependent or groundwater favoured nature objects in Forsmark. The nature objects are located in an investigation area, which contains the area that according to numerical flow modelling could be affected by groundwater-table drawdown due to groundwater diversion

Repository for spent nuclear fuel. Plant description layout D - Forsmark

International Nuclear Information System (INIS)

2010-07-01

This document describes the final repository for spent nuclear fuel, SFK, which is located at Forsmark, in Oesthammar. The bedrock at the site is part of a so-called tectonic lens, in which the rock composition is relatively homogeneous and less deformed than outside the lens. The bedrock consists mainly of granite with high quartz content and good thermal conductivity. The central parts above ground are grouped in an operations area, located at the Soederviken on the south side of the intake duct for cooling water for nuclear power plant. Operating area is divided into an internal, secured portion, where the canisters of fuel are handled and there are links to the underground part, and a outer part, where the buffer, backfill and sealing used in the repository's barriers are produced. The above-ground part of the plant and also include storage of excavated rock, ventilation stations, and supplies of bentonite. The underground portion consists of a central area and a storage area. Caverns of the central area contain features for the underground operation. It communicates with the internal operating range above ground via a spiral ramp and several shafts. The ramp used to transport capsules of spent fuel and other heavy or bulky transport. The shafts are used to transport rock, buffer, backfill and staff, as well as for ventilation. The largest part of the space below ground is the repository where the canisters with the spent fuel are disposed. The capsules are deposited in vertical holes in the tunnels. When the deposit in a tunnel is complete, the tunnel is re-filled. The two main activities underground is rock work and disposal work, which are conducted separately from each other. Rock works covers all steps required to excavate tunnels and drill deposition holes, as well as to make temporary installations in the tunnels. To the landfill works count, besides the deposit of the capsule, the placement of the bentonite buffer in the deposition hole and backfilling

Rock thermal property measurements with the Posiva TERO56 drill hole device in the forsmark study site

International Nuclear Information System (INIS)

Kukkonen, I.; Suppala, I.; Korpisalo, A.

2007-10-01

Thermal properties were measured in situ in Forsmark at the SKB study site constructed for large-scale thermal conductivity investigations in an outcrop of anisotropic granite. The Posiva TERO56 drill hole tool was used for in situ measurements in four 20 m deep boreholes KFM90C, D, E and F located within very short distances of each other (less than 2.3 m). Measurements were done at depths of 10-18 m in water-filled holes. The bedrock is granite with thin amphibolite and pegmatite layers and thin felsic veins. The measurement principle of the TERO56 logging device is based on conduction of heat from a cylindrical source placed in a borehole and the thermal parameter values are calculated with a least squares inversion algorithm. Measurements in Forsmark consisted typically of 6 hours heating time followed by 10 hours cooling time, but in one measurement the heating time was reduced to of 2 h 45 min and the cooling time to 5 hours. Average thermal conductivity values range from 3.37 to 3.91 W m -1 K -1 with standard deviations between 0.01 and 0.04 W m -1 K -1 . The result is plausible considering the quite homogeneous target geology and short distances between different experiment stations. Diffusivity values, however, vary much more, and averages range from 0.68 to 2.08 A 10 -6 m 2 s -1 with standard deviations ranging from 0.04 to 0.09 A 10 -6 m 2 s -1 . Variations may be attributed to small flow effects or time-dependent temperature trends related to thermal equilibration of the probe. (orig.)

Groundwater flow modelling of the excavation and operational phases - Forsmark

Energy Technology Data Exchange (ETDEWEB)

Svensson, Urban (Computer-aided Fluid Engineering AB, Lyckeby (Sweden)); Follin, Sven (SF GeoLogic AB, Taeby (Sweden))

2010-07-15

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different climate conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The modelling study reported here presents calculated inflow rates, drawdown of the groundwater table and upconing of deep saline water for different levels of grouting efficiency during the excavation and operational phases of a final repository at Forsmark. The inflow calculations are accompanied by a sensitivity study, which among other matters handles the impact of parameter heterogeneity, different deposition hole rejection criteria, and the SFR facility (the repository for short-lived radioactive waste located approximately 1 km to the north of the investigated candidate area for a final repository at Forsmark). The report also presents tentative modelling results for the duration of the saturation phase, which starts once the used parts of the repository are being backfilled.

Groundwater flow modelling of the excavation and operational phases - Forsmark

International Nuclear Information System (INIS)

Svensson, Urban; Follin, Sven

2010-07-01

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different climate conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The modelling study reported here presents calculated inflow rates, drawdown of the groundwater table and upconing of deep saline water for different levels of grouting efficiency during the excavation and operational phases of a final repository at Forsmark. The inflow calculations are accompanied by a sensitivity study, which among other matters handles the impact of parameter heterogeneity, different deposition hole rejection criteria, and the SFR facility (the repository for short-lived radioactive waste located approximately 1 km to the north of the investigated candidate area for a final repository at Forsmark). The report also presents tentative modelling results for the duration of the saturation phase, which starts once the used parts of the repository are being backfilled

SR-Site - hydrogeochemical evolution of the Forsmark site

International Nuclear Information System (INIS)

Salas, Joaquin; Molinero, Jorge; Juarez, Iker; Gimeno, Maria Jose; Auque, Luis; Gomez, Javier

2010-12-01

The present work has involved the development of a methodology in order to simulate the evolution of the groundwater composition within the candidate repository site of the Forsmark area. A series of climate periods is expected to be probable after the repository closure (temperate, periglacial and glacial) and, eventually, the area could be submerged under seawaters or under a lake of glacial melt waters. These environmental conditions will affect groundwater flow and composition around of the candidate repository volume. The present report summarizes the results obtained by the calculations which reproduce the hydrogeochemical evolution in the Forsmark area, and within the candidate repository volume. The hydrogeochemical evolution of groundwaters is one of the key factors affecting the chemical stability of the buffer and the canister. In this way, the main objective of the hydrogeochemical simulations is to assay the evolution of a series of safety assessment factors, such as salinity, redox potential, pH, and concentrations of iron, sulphide and potassium, among others. Using ConnectFlow, previous hydrological calculations have provided the transport of (1) the fractions of selected reference waters (Deep Saline, Old Meteoric, Glacial, Littorina and Altered Meteoric groundwaters), or (2) salinities, depending on the working team (Serco or Terrasolve). The results of the regional-scale groundwater flow modelling for each specific climate period are used as input of the geochemical models. Groundwater compositions have been modelled using PHREEQC, through mixing and chemical reactions between the waters obtained from the hydrogeological models and the reactive fracture-filling minerals. Both models (hydrological and geochemical) are not fully coupled, and it allows a description of the geochemical heterogeneity, which otherwise would be hard to attain. The stage of the open repository has been non-numerically analysed. Aspects as salinity, redox conditions

SR-Site - hydrogeochemical evolution of the Forsmark site

Energy Technology Data Exchange (ETDEWEB)

Salas, Joaquin; Molinero, Jorge; Juarez, Iker (Amphos 21 (Spain)); Gimeno, Maria Jose; Auque, Luis; Gomez, Javier (Univ. of Zaragoza (Spain))

2010-12-15

The present work has involved the development of a methodology in order to simulate the evolution of the groundwater composition within the candidate repository site of the Forsmark area. A series of climate periods is expected to be probable after the repository closure (temperate, periglacial and glacial) and, eventually, the area could be submerged under seawaters or under a lake of glacial melt waters. These environmental conditions will affect groundwater flow and composition around of the candidate repository volume. The present report summarizes the results obtained by the calculations which reproduce the hydrogeochemical evolution in the Forsmark area, and within the candidate repository volume. The hydrogeochemical evolution of groundwaters is one of the key factors affecting the chemical stability of the buffer and the canister. In this way, the main objective of the hydrogeochemical simulations is to assay the evolution of a series of safety assessment factors, such as salinity, redox potential, pH, and concentrations of iron, sulphide and potassium, among others. Using ConnectFlow, previous hydrological calculations have provided the transport of (1) the fractions of selected reference waters (Deep Saline, Old Meteoric, Glacial, Littorina and Altered Meteoric groundwaters), or (2) salinities, depending on the working team (Serco or Terrasolve). The results of the regional-scale groundwater flow modelling for each specific climate period are used as input of the geochemical models. Groundwater compositions have been modelled using PHREEQC, through mixing and chemical reactions between the waters obtained from the hydrogeological models and the reactive fracture-filling minerals. Both models (hydrological and geochemical) are not fully coupled, and it allows a description of the geochemical heterogeneity, which otherwise would be hard to attain. The stage of the open repository has been non-numerically analysed. Aspects as salinity, redox conditions

The Greenland Analogue Project (GAP). Literature review of hydrogeology/ hydrogeochemistry

Energy Technology Data Exchange (ETDEWEB)

Wallroth, Thomas; Lokrantz, Hanna; Rimsa, Andrius (Bergab Consulting Geologists, Goeteborg (Sweden))

2010-09-15

This report is produced as part of the Greenland Analogue Project (GAP), carried out as a collaboration project with the Canadian Nuclear Waste Management Organization (NWMO), Posiva Oy and the Swedish Nuclear Fuel and Waste Management Co (SKB). The overall aim of the project is to improve the current understanding of hydrogeological and hydrogeochemical processes associated with continental-scale glacial periods including with the presence of permafrost and the advance/retreat of ice sheets. The project will focus on studying how an ice sheet affects groundwater flow and water chemistry around a deep geological repository in crystalline bedrock. The Greenland Analogue Project consists of three active sub-projects (A-C) with individual objectives. Field studies are conducted in the Kangerlussuaq region, in central Western Greenland. Sub-projects A and B collectively aim at improving the understanding of ice sheet hydrology by combining investigations on surface water processes with ice sheet drilling and instrumentation. In sub-project C, the penetration of glacial melt water into the bedrock, groundwater flow and the chemical composition of water will be studied. Main planned activities in sub-project C include drilling of a deep borehole in front of the ice sheet, in which different downhole surveys, sampling and monitoring will be carried out. The primary aim of this report is to review available information about hydrogeology and hydrogeochemistry in central Western Greenland, with special emphasis on the area around Kangerlussuaq. The relevant information about this area is however very limited, and it was decided to extend the review to briefly include studies made in other regions with similar conditions in terms of geology, climate and glaciology. The number of published studies made in other areas with glaciers, ice sheets or permafrost is very large, and the review and list of references in this report is far from complete. It is also obvious that both

The Greenland Analogue Project (GAP). Literature review of hydrogeology/ hydrogeochemistry

International Nuclear Information System (INIS)

Wallroth, Thomas; Lokrantz, Hanna; Rimsa, Andrius

2010-09-01

This report is produced as part of the Greenland Analogue Project (GAP), carried out as a collaboration project with the Canadian Nuclear Waste Management Organization (NWMO), Posiva Oy and the Swedish Nuclear Fuel and Waste Management Co (SKB). The overall aim of the project is to improve the current understanding of hydrogeological and hydrogeochemical processes associated with continental-scale glacial periods including with the presence of permafrost and the advance/retreat of ice sheets. The project will focus on studying how an ice sheet affects groundwater flow and water chemistry around a deep geological repository in crystalline bedrock. The Greenland Analogue Project consists of three active sub-projects (A-C) with individual objectives. Field studies are conducted in the Kangerlussuaq region, in central Western Greenland. Sub-projects A and B collectively aim at improving the understanding of ice sheet hydrology by combining investigations on surface water processes with ice sheet drilling and instrumentation. In sub-project C, the penetration of glacial melt water into the bedrock, groundwater flow and the chemical composition of water will be studied. Main planned activities in sub-project C include drilling of a deep borehole in front of the ice sheet, in which different downhole surveys, sampling and monitoring will be carried out. The primary aim of this report is to review available information about hydrogeology and hydrogeochemistry in central Western Greenland, with special emphasis on the area around Kangerlussuaq. The relevant information about this area is however very limited, and it was decided to extend the review to briefly include studies made in other regions with similar conditions in terms of geology, climate and glaciology. The number of published studies made in other areas with glaciers, ice sheets or permafrost is very large, and the review and list of references in this report is far from complete. It is also obvious that both

Recharge-area nuclear waste repository in southeastern Sweden. Demonstration of hydrogeologic siting concepts and techniques

International Nuclear Information System (INIS)

Provost, A.M.; Voss, C.I.

2001-11-01

Nuclear waste repositories located in regional ground-water recharge ('upstream') areas may provide the safety advantage that potentially released radionuclides would have long travel time and path length, and large path volume, within the bedrock before reaching the biosphere. Nuclear waste repositories located in ground-water discharge ('downstream') areas likely have much shorter travel time and path length and smaller path volume. Because most coastal areas are near the primary discharge areas for regional ground-water flow, coastal repositories may have a lower hydrogeologic safety margin than 'upstream' repositories located inland. Advantageous recharge-area sites may be located through careful use of regional three-dimensional, variable-density, ground-water modeling. Because of normal limitations of site-characterization programs in heterogeneous bedrock environments, the hydrogeologic structure and properties of the bedrock will generally remain unknown at the spatial scales required for the model analysis, and a number of alternative bedrock descriptions are equally likely. Model simulations need to be carried out for the full range of possible descriptions. The favorable sites are those that perform well for all of the modeled bedrock descriptions. Structural heterogeneities in the bedrock and local undulations in water-table topography, at a scale finer than considered by a given model, also may cause some locations in favored inland areas to have very short flow paths (of only hundreds of meters) and short travel times, compromising the long times and paths (of many kilometers) predicted by the analysis for these sites. However, in the absence of more detailed modeling, the favored upstream sites offer a greater chance of achieving long times and paths than do downstream discharge areas, where times and paths are expected to be short regardless of the level of detail included in the model. As an example of this siting approach, potential repository

Simulated carbon and water processes of forest ecosystems in Forsmark and Oskarshamn during a 100-year period

International Nuclear Information System (INIS)

Gustafsson, David; Jansson, Per-Erik; Gaerdenaes, Annemieke; Eckersten, Henrik

2006-12-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is currently investigating the Forsmark and Oskarshamn areas for possible localisation of a repository for spent nuclear fuel. Important components of the investigations are characterizations of the land surface ecosystems in the areas with respect to hydrological and biological processes, and their implications for the fate of radionuclide contaminants entering the biosphere from a shallow groundwater contamination. In this study, we simulate water balance and carbon turnover processes in forest ecosystems representative for the Forsmark and Oskarshamn areas for a 100-year period using the ecosystem process model CoupModel. The CoupModel describes the fluxes of water and matter in a one-dimensional soil-vegetation-atmosphere system, forced by time series of meteorological variables. The model has previously been parameterized for many of the vegetation systems that can be found in the Forsmark and Oskarshamn areas: spruce/pine forests, willow, grassland and different agricultural crops. This report presents a platform for further use of models like CoupModel for investigations of radionuclide turnover in the Forsmark and Oskarshamn area based on SKB data, including a data set of meteorological forcing variables for Forsmark 1970-2004, suitable for simulations of a 100-year period representing the present day climate, a hydrological parameterization of the CoupModel for simulations of the forest ecosystems in the Forsmark and Oskarshamn areas, and simulated carbon budgets and process descriptions for Forsmark that correspond to a possible steady state of the soil storage of the forest ecosystem

Simulated carbon and water processes of forest ecosystems in Forsmark and Oskarshamn during a 100-year period

Energy Technology Data Exchange (ETDEWEB)

Gustafsson, David; Jansson, Per-Erik [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Land and Water Resources Engineering; Gaerdenaes, Annemieke [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Soil Sciences; Eckersten, Henrik [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Crop Production Ecology

2006-12-15

The Swedish Nuclear Fuel and Waste Management Co (SKB) is currently investigating the Forsmark and Oskarshamn areas for possible localisation of a repository for spent nuclear fuel. Important components of the investigations are characterizations of the land surface ecosystems in the areas with respect to hydrological and biological processes, and their implications for the fate of radionuclide contaminants entering the biosphere from a shallow groundwater contamination. In this study, we simulate water balance and carbon turnover processes in forest ecosystems representative for the Forsmark and Oskarshamn areas for a 100-year period using the ecosystem process model CoupModel. The CoupModel describes the fluxes of water and matter in a one-dimensional soil-vegetation-atmosphere system, forced by time series of meteorological variables. The model has previously been parameterized for many of the vegetation systems that can be found in the Forsmark and Oskarshamn areas: spruce/pine forests, willow, grassland and different agricultural crops. This report presents a platform for further use of models like CoupModel for investigations of radionuclide turnover in the Forsmark and Oskarshamn area based on SKB data, including a data set of meteorological forcing variables for Forsmark 1970-2004, suitable for simulations of a 100-year period representing the present day climate, a hydrological parameterization of the CoupModel for simulations of the forest ecosystems in the Forsmark and Oskarshamn areas, and simulated carbon budgets and process descriptions for Forsmark that correspond to a possible steady state of the soil storage of the forest ecosystem.

Forsmark site investigation. Detailed ground magnetic survey and lineament interpretation in the Forsmark area, 2006-2007

Energy Technology Data Exchange (ETDEWEB)

Isaksson, Hans; Thunehed, Hans; Pitkaenen, Timo; Keisu, Mikael (GeoVista AB, Luleaa (SE))

2007-12-15

The report presents detailed ground magnetic measurements carried out on an 11.1 km2 area in the Forsmark site investigation area. The main objective of this activity is to determine a detailed ground magnetic representation of the bedrock. The results from previous surveys were encouraging and have led to a broad geophysical programme for investigation of lineaments at Forsmark. This report comprises the results from the second and final phase of the extended survey programme and a compilation and summary of all phases in the programme. On ground and on lake ice, a grid with parallel lines was staked. Measurements of the magnetic total field were carried out along profiles, perpendicular to the staked lines, with a profile spacing of 10 m and a station spacing of 5 m. Measurements on the ice-covered sea bays were carried out by a two man crew. One crew member walked along the survey lines, carrying a RTK-GPS guiding the other crew member who measured the magnetic total field. No seaborne survey was carried out in the final phase. Previously, using a high accuracy RTK-GPS unit for boat navigation gave a seaborne survey grid of on average 10 m line spacing and 2-3 m station spacing. In total 427,238 magnetic survey stations have been measured and an area of 4.7 km2 has been surveyed from boat. The magnetic pattern in the survey area can be divided into six main areas with different magnetic character. Along the southwest margin of the survey area the magnetic pattern is intensely banded with rapidly changing low and highly magnetic bands striking southeast-northwest, which to the northeast changes to a gentler, banded pattern of low to moderate magnetic intensity. To the northeast, at the SFR office and along the coastline to the southeast, the pattern is again intensely banded with, southeast-northwest trending, rapidly changing low and highly magnetic bands. These two banded structures probably forms fold limbs of a common fold with a northwest oriented fold axis

A preliminary carbon budget for two oligotrophic hardwater lakes in the Forsmark area, Sweden

Energy Technology Data Exchange (ETDEWEB)

Nilsson, Eva [Uppsala Univ. (Sweden). Dept. of Limnology

2001-06-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is responsible for management and disposal of Swedish radioactive waste. The company is planning to construct repositories that will keep radioactive waste away from humans for hundreds of thousands of years. In a safety assessment of the repositories hypothetical releases are used to evaluate the robustness of the repositories. It is important to know how the radioactive nuclides would react if they were released and by which way they could enter the living biota. SFR are responsible for the disposal of low radioactive waste and close to the nuclear plant in Forsmark there is a storage for low radioactive waste. At the moment this storage is located in the bedrock far below the sea level but due to land-rise in the area it will in the future be located above sea level. Hence, it is of importance to know how the surface ecosystems in the area are functioning. A carbon budget for the aquatic ecosystem above SFR in Oeresundsgrepen exist, but it is also important to have a carbon budget for the surface systems in the Forsmark area since SFR in the future will be situated above sea level. Carbon budgets can be used to get a picture of how an ecosystem functions. The carbon flow shows how carbon is transported through a food web from lower trophic levels, e.g. plants and bacteria to higher trophic levels such as fish. Oligotrophic hardwater lakes are the most important lakes in the Forsmark area. This report aims to give a picture of a potential flow of carbon through the ecosystem in two oligotrophic hard-water lakes, Lake Haellefjaerd and Lake Eckarfjaerden. Macrophyte, mainly Chara, were calculated to make up the largest part of the biomass and production in both lakes. Benthic bacteria and microphytobenthos (benthic photosynthesising microorganisms) were other large contributors to the production. Benthic bacteria were found responsible for a major part of respiration and, hence, consumption of carbon in the

A preliminary carbon budget for two oligotrophic hardwater lakes in the Forsmark area, Sweden

International Nuclear Information System (INIS)

Nilsson, Eva

2001-06-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is responsible for management and disposal of Swedish radioactive waste. The company is planning to construct repositories that will keep radioactive waste away from humans for hundreds of thousands of years. In a safety assessment of the repositories hypothetical releases are used to evaluate the robustness of the repositories. It is important to know how the radioactive nuclides would react if they were released and by which way they could enter the living biota. SFR are responsible for the disposal of low radioactive waste and close to the nuclear plant in Forsmark there is a storage for low radioactive waste. At the moment this storage is located in the bedrock far below the sea level but due to land-rise in the area it will in the future be located above sea level. Hence, it is of importance to know how the surface ecosystems in the area are functioning. A carbon budget for the aquatic ecosystem above SFR in Oeresundsgrepen exist, but it is also important to have a carbon budget for the surface systems in the Forsmark area since SFR in the future will be situated above sea level. Carbon budgets can be used to get a picture of how an ecosystem functions. The carbon flow shows how carbon is transported through a food web from lower trophic levels, e.g. plants and bacteria to higher trophic levels such as fish. Oligotrophic hardwater lakes are the most important lakes in the Forsmark area. This report aims to give a picture of a potential flow of carbon through the ecosystem in two oligotrophic hard-water lakes, Lake Haellefjaerd and Lake Eckarfjaerden. Macrophyte, mainly Chara, were calculated to make up the largest part of the biomass and production in both lakes. Benthic bacteria and microphytobenthos (benthic photosynthesising microorganisms) were other large contributors to the production. Benthic bacteria were found responsible for a major part of respiration and, hence, consumption of carbon in the

The limnic ecosystems at Forsmark and Laxemar-Simpevarp

Energy Technology Data Exchange (ETDEWEB)

Andersson, Eva

2010-12-15

The overall objective of this report is to describe the limnic ecosystems at Forsmark and Laxemar- Simpevarp, identify important processes in a radionuclide perspective and provide a description of the radionuclide model for the biosphere used in SR-Site. The report includes a thorough description of the lakes and streams in Forsmark and Laxemar- Simpevarp and covers the following areas: catchment area characteristics, hydrology, climate, sediment characteristics, physical characteristics of streams, habitat distribution in lakes, biotic components (biomass as well as production), water chemistry, and comparison with other lakes and streams in the region, and a historical description. Ecosystem models for carbon and mass balances for a number of elements have been calculated to further improve the understanding of the lake ecosystems. Important processes for the safety assessment are described and evaluated in the report. A separate chapter is included to specifically describe how and where these processes are included in the radionuclide model. The radionuclide model is described and parameterisation and guidance to parameter calculation is provided. The last chapter of the report provides a summary of the knowledge of the limnic systems at the two areas. The Forsmark regional model area contains more than 25 permanent lakes and pools. All lakes are small and shallow, and are characterized as oligotrophic hardwater lakes. Calcareous soils in the area give rise to high calcium concentrations in the surface water, which in turn leads to high pH and low nutrient concentrations in water as phosphorus often co-precipitates with calcium. The shallow depths and moderate water colour permit photosynthesis in the entire benthic habitat of the lakes, and the bottoms are covered by dense stands of the macroalgae Chara sp. Moreover, many of the lakes also have a thick microbial mat (>10 cm), consisting of cyanobacteria and diatoms, in the benthic habitat. Fish in the lakes

The limnic ecosystems at Forsmark and Laxemar-Simpevarp

International Nuclear Information System (INIS)

Andersson, Eva

2010-12-01

The overall objective of this report is to describe the limnic ecosystems at Forsmark and Laxemar- Simpevarp, identify important processes in a radionuclide perspective and provide a description of the radionuclide model for the biosphere used in SR-Site. The report includes a thorough description of the lakes and streams in Forsmark and Laxemar- Simpevarp and covers the following areas: catchment area characteristics, hydrology, climate, sediment characteristics, physical characteristics of streams, habitat distribution in lakes, biotic components (biomass as well as production), water chemistry, and comparison with other lakes and streams in the region, and a historical description. Ecosystem models for carbon and mass balances for a number of elements have been calculated to further improve the understanding of the lake ecosystems. Important processes for the safety assessment are described and evaluated in the report. A separate chapter is included to specifically describe how and where these processes are included in the radionuclide model. The radionuclide model is described and parameterisation and guidance to parameter calculation is provided. The last chapter of the report provides a summary of the knowledge of the limnic systems at the two areas. The Forsmark regional model area contains more than 25 permanent lakes and pools. All lakes are small and shallow, and are characterized as oligotrophic hardwater lakes. Calcareous soils in the area give rise to high calcium concentrations in the surface water, which in turn leads to high pH and low nutrient concentrations in water as phosphorus often co-precipitates with calcium. The shallow depths and moderate water colour permit photosynthesis in the entire benthic habitat of the lakes, and the bottoms are covered by dense stands of the macroalgae Chara sp. Moreover, many of the lakes also have a thick microbial mat (>10 cm), consisting of cyanobacteria and diatoms, in the benthic habitat. Fish in the lakes

Fault zone hydrogeology

Science.gov (United States)

Bense, V. F.; Gleeson, T.; Loveless, S. E.; Bour, O.; Scibek, J.

2013-12-01

Deformation along faults in the shallow crust (research effort of structural geologists and hydrogeologists. However, we find that these disciplines often use different methods with little interaction between them. In this review, we document the current multi-disciplinary understanding of fault zone hydrogeology. We discuss surface- and subsurface observations from diverse rock types from unlithified and lithified clastic sediments through to carbonate, crystalline, and volcanic rocks. For each rock type, we evaluate geological deformation mechanisms, hydrogeologic observations and conceptual models of fault zone hydrogeology. Outcrop observations indicate that fault zones commonly have a permeability structure suggesting they should act as complex conduit-barrier systems in which along-fault flow is encouraged and across-fault flow is impeded. Hydrogeological observations of fault zones reported in the literature show a broad qualitative agreement with outcrop-based conceptual models of fault zone hydrogeology. Nevertheless, the specific impact of a particular fault permeability structure on fault zone hydrogeology can only be assessed when the hydrogeological context of the fault zone is considered and not from outcrop observations alone. To gain a more integrated, comprehensive understanding of fault zone hydrogeology, we foresee numerous synergistic opportunities and challenges for the discipline of structural geology and hydrogeology to co-evolve and address remaining challenges by co-locating study areas, sharing approaches and fusing data, developing conceptual models from hydrogeologic data, numerical modeling, and training interdisciplinary scientists.

Characteristics and ontogeny of oligotrophic hardwater lakes in the Forsmark area, central Sweden

Energy Technology Data Exchange (ETDEWEB)

Brunberg, A.K.; Blomqvist, P. [Uppsala Univ. (Sweden). Dept. of Limnology

1999-12-01

This is the first part of a report characterising the lakes of Uppsala county, with special emphasis on the coastal lakes in the Forsmark area.The aim of the study is to characterise different main types of lakes within the Forsmark area and to create a basis for prediction of their ontogeny, that can be used also for new lakes which due to shoreline displacement will be formed during the next 10 000 years. Areas where future research is needed to fully understand the functioning of the lake ecosystems and their ontogeny should also be identified. This first part of the study identifies and describes one of the most common lake types in the area, the oligotrophic hardwater lake. The geology in the catchments of the Forsmark area includes a bedrock dominated by granites and gneisses, covered by calcareous glacial till and postglacial clay. The catchments are dominated by forest, and the oligotrophic hardwater lakes are to a large extent surrounded by mires. Inflow as well as outflow of water is often diffuse, via the surrounding mire. The lakes are small and shallow, with nutrient poor and highly alkaline water. Three key habitats have been identified within the lakes; the pelagic zone, characterised by low production of biota;, the presumably moderately productive emergent macrophyte zone, dominated by Sphagnum and Phragmites;, and the light exposed soft-bottom zone with Chara meadows and an unusually rich and presumably highly productive microbial sediment community. The oligotrophic hardwater lakes have their origin as depressions in the bottom of the Baltic Sea, which are successively transported upwards due to the land-rise process in the area. As the basins are isolated from the sea , a gradual change from a brackish to freshwater conditions occur. When the lakes have become completely isolated, the oligotrophic hardwater stage follows, due to inflow of carbonate-rich and well buffered groundwater. In the next successional stage, Sphagnum mosses start to

Characteristics and ontogeny of oligotrophic hardwater lakes in the Forsmark area, central Sweden

International Nuclear Information System (INIS)

Brunberg, A.K.; Blomqvist, P.

1999-12-01

This is the first part of a report characterising the lakes of Uppsala county, with special emphasis on the coastal lakes in the Forsmark area.The aim of the study is to characterise different main types of lakes within the Forsmark area and to create a basis for prediction of their ontogeny, that can be used also for new lakes which due to shoreline displacement will be formed during the next 10 000 years. Areas where future research is needed to fully understand the functioning of the lake ecosystems and their ontogeny should also be identified. This first part of the study identifies and describes one of the most common lake types in the area, the oligotrophic hardwater lake. The geology in the catchments of the Forsmark area includes a bedrock dominated by granites and gneisses, covered by calcareous glacial till and postglacial clay. The catchments are dominated by forest, and the oligotrophic hardwater lakes are to a large extent surrounded by mires. Inflow as well as outflow of water is often diffuse, via the surrounding mire. The lakes are small and shallow, with nutrient poor and highly alkaline water. Three key habitats have been identified within the lakes; the pelagic zone, characterised by low production of biota;, the presumably moderately productive emergent macrophyte zone, dominated by Sphagnum and Phragmites;, and the light exposed soft-bottom zone with Chara meadows and an unusually rich and presumably highly productive microbial sediment community. The oligotrophic hardwater lakes have their origin as depressions in the bottom of the Baltic Sea, which are successively transported upwards due to the land-rise process in the area. As the basins are isolated from the sea , a gradual change from a brackish to freshwater conditions occur. When the lakes have become completely isolated, the oligotrophic hardwater stage follows, due to inflow of carbonate-rich and well buffered groundwater. In the next successional stage, Sphagnum mosses start to

The Laxemar and Forsmark repositories. An analysis of the water inflow distribution

International Nuclear Information System (INIS)

Svensson, Urban

2006-12-01

A numerical simulation model is used to estimate the water inflow distribution to the Laxemar and Forsmark repositories. In particular statistics for the inflow to individual deposition holes, i.e. inflow distribution expressed as litre/min, deposition hole, is requested. Different grouting efficiencies are evaluated, including no grouting. The simulations are based on the code DarcyTools version 3.0, which was also used in simulations of the impact of the Repositories in Forsmark and Laxemar. Both the code and the simulations include many novel features and all simulations should hence be regarded as tentative. For the Laxemar repository it is found that less than 2% of all deposition holes will have an inflow larger than 1.0 l/min. This number will increase to about 20% if the inflow limit is put to 0.1 l/min. For the Forsmark repository it is found that 99.9% of all deposition holes will have an inflow smaller than 0.01 l/min

Operative meteorological data base in Forsmark

International Nuclear Information System (INIS)

Appelgren, A.; Hallberg, B.; Nordlinder, S.

1990-01-01

This report describes how data collected during a field measurement campaign were analysed and compiled to create a data base for operative use. The data base gives information about the wind and the atmospheric stability at five locations around the Forsmark nuclear power plant. In the measurement campaign, sodar systems and a 100 m high tower at Forsmark were used. Temperature, wind speed and wind direction were measured by sensors on the tower, while wind speed and direction, and the standard deviation of the vertical wind, were monitored by the sodar systems. This gave meteorological data from several heights. At Forsmark, the temperature difference and the wind speed from the tower were used to determine the atmospheric stability. At the sodar locations, the stability was deduced by employing a scheme which considered the season, the time of day, the wind direction and the wind speed. To create the operative data base, the wind speeds and wind directions, respectively, from two locations at the time were correlated. A code for graphical and numerical presentation of the data from the data base was developed. A special system of warnings was included, featuring notification about phenomena such as sea breeze, warnings about large variation in the wind conditions within the area, and warnings for situations in which the meteorological conditions make the results from the atmospheric dispersion calculations uncertain. This feature was implemented to alert the user to the fact that ordinary dispersion and dose calculations, using meteorological data from a single point, might give erroneous results. The operative data base and the presentation code were integrated with the dispersion and dose calculation code AIRPAC/EMMA, which is to be used in case of increased releases from nuclear power plants. The possibility to use the data from the operative data base in the dispersion calculations was investigated. It was found that a modification of AIRPAC/EMMA, in such a

Subsidence analysis Forsmark nuclear power plant - unit 1

International Nuclear Information System (INIS)

Bono, Nancy; Fredriksson, Anders; Maersk Hansen, Lars

2010-12-01

On behalf of SKB, Golder Associates Ltd carried out a risk analysis of subsidence during Forsmark nuclear power plant in the construction of the final repository for spent nuclear fuel near and below existing reactors. Specifically, the effect of horizontal cracks have been studied

Confidence assessment. Site descriptive modelling SDM-Site Forsmark

International Nuclear Information System (INIS)

2008-09-01

The objective of this report is to assess the confidence that can be placed in the Forsmark site descriptive model, based on the information available at the conclusion of the surface-based investigations (SDM-Site Forsmark). In this exploration, an overriding question is whether remaining uncertainties are significant for repository engineering design or long-term safety assessment and could successfully be further reduced by more surface based investigations or more usefully by explorations underground made during construction of the repository. The confidence in the Forsmark site descriptive model, based on the data available at the conclusion of the surface-based site investigations, have been assessed by exploring: Confidence in the site characterisation data base; Key remaining issues and their handling; Handling of alternative models; Consistency between disciplines; and, Main reasons for confidence and lack of confidence in the model. It is generally found that the key aspects of importance for safety assessment and repository engineering of the Forsmark site descriptive model are associated with a high degree of confidence. Because of the robust geological model that describes the site, the overall confidence in Forsmark site descriptive model is judged to be high. While some aspects have lower confidence this lack of confidence is handled by providing wider uncertainty ranges, bounding estimates and/or alternative models. Most, but not all, of the low confidence aspects have little impact on repository engineering design or for long-term safety. Poor precision in the measured data are judged to have limited impact on uncertainties on the site descriptive model, with the exceptions of inaccuracy in determining the position of some boreholes at depth in 3-D space, as well as the poor precision of the orientation of BIPS images in some boreholes, and the poor precision of stress data determined by overcoring at the locations where the pre

The potential for ore and industrial minerals in the Forsmark area

Energy Technology Data Exchange (ETDEWEB)

Lindroos, Hardy [MIRAB Mineral Resurser AB, Uppsala (Sweden); Isaksson, Hans; Thunehed, Hans [GeoVista AB, Luleaa (Sweden)

2004-03-01

A survey has been made of existing information concerning the potential for ore and industrial minerals in and near the candidate area for a deep repository in Forsmark. A deep repository for spent nuclear fuel should not be located in a rock type or an area where mineral extraction might be considered in the future, since this would make it impossible to exploit this natural resource. Avoiding such areas reduces the risk that people in the future will come into contact with the deep repository through mineral prospecting or mining activities. The survey has made use of all the geoscientific information that was compiled in the more regional investigations in Oesthammar Municipality in 1996-97. In cooperation with the Geological Survey of Sweden (SGU), a new, more detailed mineral resources map has been prepared. The map shows areas with an ore potential that may be unsuitable or unfavourable for siting of a deep repository. The results of the recently completed geophysical helicopter surveys of the Forsmark area are presented in a special chapter. The judgement of the area's ore potential is in part based on the geophysical evaluation of these measurements. Furthermore, the survey obtained information from ongoing deep drillings from the site investigation in Forsmark. In order to better be able to judge the ore potential, the survey has initiated a geochemical investigation of activated soil samples, plus an ore geology sampling of a section in the deep borehole KFM02A, where a hydrothermally altered zone was detected in 2003.The first results from these samplings are presented in the report, which also discusses prospecting efforts in the area as well as relevant Swedish mining legislation. Some suggestions are made for further ore geology investigations. The mineral resources map shows that there is an elongate northwest-southeast zone south and southwest of the candidate area which has a potential for skarn iron ore, and possibly for copper and zinc

The potential for ore and industrial minerals in the Forsmark area

International Nuclear Information System (INIS)

Lindroos, Hardy; Isaksson, Hans; Thunehed, Hans

2004-03-01

A survey has been made of existing information concerning the potential for ore and industrial minerals in and near the candidate area for a deep repository in Forsmark. A deep repository for spent nuclear fuel should not be located in a rock type or an area where mineral extraction might be considered in the future, since this would make it impossible to exploit this natural resource. Avoiding such areas reduces the risk that people in the future will come into contact with the deep repository through mineral prospecting or mining activities. The survey has made use of all the geoscientific information that was compiled in the more regional investigations in Oesthammar Municipality in 1996-97. In cooperation with the Geological Survey of Sweden (SGU), a new, more detailed mineral resources map has been prepared. The map shows areas with an ore potential that may be unsuitable or unfavourable for siting of a deep repository. The results of the recently completed geophysical helicopter surveys of the Forsmark area are presented in a special chapter. The judgement of the area's ore potential is in part based on the geophysical evaluation of these measurements. Furthermore, the survey obtained information from ongoing deep drillings from the site investigation in Forsmark. In order to better be able to judge the ore potential, the survey has initiated a geochemical investigation of activated soil samples, plus an ore geology sampling of a section in the deep borehole KFM02A, where a hydrothermally altered zone was detected in 2003.The first results from these samplings are presented in the report, which also discusses prospecting efforts in the area as well as relevant Swedish mining legislation. Some suggestions are made for further ore geology investigations. The mineral resources map shows that there is an elongate northwest-southeast zone south and southwest of the candidate area which has a potential for skarn iron ore, and possibly for copper and zinc, although

Preliminary site description: Groundwater flow simulations. Simpevarp area (version 1.1) modelled with CONNECTFLOW

International Nuclear Information System (INIS)

Hartley, Lee; Worth, David; Gylling, Bjoern; Marsic, Niko; Holmen, Johan

2004-08-01

The main objective of this study is to assess the role of known and unknown hydrogeological conditions for the present-day distribution of saline groundwater at the Simpevarp and Laxemar sites. An improved understanding of the paleo-hydrogeology is necessary in order to gain credibility for the Site Descriptive Model in general and the Site Hydrogeological Description in particular. This is to serve as a basis for describing the present hydrogeological conditions as well as predictions of future hydrogeological conditions. This objective implies a testing of: geometrical alternatives in the structural geology and bedrock fracturing, variants in the initial and boundary conditions, and parameter uncertainties (i.e. uncertainties in the hydraulic property assignment). This testing is necessary in order to evaluate the impact on the groundwater flow field of the specified components and to promote proposals of further investigations of the hydrogeological conditions at the site. The general methodology for modelling transient salt transport and groundwater flow using CONNECTFLOW that was developed for Forsmark has been applied successfully also for Simpevarp. Because of time constraints only a key set of variants were performed that focussed on the influences of DFN model parameters, the kinematic porosity, and the initial condition. Salinity data in deep boreholes available at the time of the project was too limited to allow a good calibration exercise. However, the model predictions are compared with the available data from KLX01 and KLX02 below. Once more salinity data is available it may be possible to draw more definite conclusions based on the differences between variants. At the moment though the differences should just be used understand the sensitivity of the models to various input parameters

Occurrence of methane in groundwater of south-central New York State, 2012-systematic evaluation of a glaciated region by hydrogeologic setting

Science.gov (United States)

Heisig, Paul M.; Scott, Tia-Marie

2013-01-01

A survey of methane in groundwater was undertaken to document methane occurrence on the basis hydrogeologic setting within a glaciated 1,810-square-mile area of south-central New York along the Pennsylvania border. Sixty-six wells were sampled during the summer of 2012. All wells were at least 1 mile from any known gas well (active, exploratory, or abandoned). Results indicate strong positive and negative associations between hydrogeologic settings and methane occurrence. The hydrogeologic setting classes are based on topographic position (valley and upland), confinement or non-confinement of groundwater by glacial deposits, well completion in fractured bedrock or sand and gravel, and hydrogeologic subcategories. Only domestic wells and similar purposed supply wells with well-construction and log information were selected for classification. Field water-quality characteristics (pH, specific conductance, dissolved oxygen, and temperature) were measured at each well, and samples were collected and analyzed for dissolved gases, including methane and short-chain hydrocarbons. Carbon and hydrogen isotopic ratios of methane were measured in 21 samples that had at least 0.3 milligram per liter (mg/L) of methane. Results of sampling indicate that occurrence of methane in groundwater of the region is common—greater than or equal to 0.001 mg/L in 78 percent of the groundwater samples. Concentrations of methane ranged over five orders of magnitude. Methane concentrations at which monitoring or mitigation are indicated (greater than or equal to 10 mg/L) were measured in 15 percent of the samples. Methane concentrations greater than 0.1 mg/L were associated with specific hydrogeologic settings. Wells completed in bedrock within valleys and under confined groundwater conditions were most closely associated with the highest methane concentrations. Fifty-seven percent of valley wells had greater than or equal to 0.1 mg/L of methane, whereas only 10 percent of upland wells

Hydrogeological DFN modelling using structural and hydraulic data from KLX04. Preliminary site description Laxemar subarea - version 1.2

Energy Technology Data Exchange (ETDEWEB)

Follin, Sven [SF GeoLogic AB, Taeby (Sweden); Stigsson, Martin [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Svensson, Urban [Computer-aided Fluid Engineering AB, Norrkoeping (Sweden)

2006-04-15

SKB is conducting site investigations for a high-level nuclear waste repository in fractured crystalline rocks at two coastal areas in Sweden. The two candidate areas are named Forsmark and Simpevarp. The site characterisation work is divided into two phases, an initial site investigation phase (ISI) and a complete site investigation phase (CSI). The results of the ISI phase are used as a basis for deciding on the subsequent CSI phase. On the basis of the CSI investigations a decision is made as to whether detailed characterisation will be performed (including sinking of a shaft). An integrated component in the site characterisation work is the development of site descriptive models. These comprise basic models in three dimensions with an accompanying text description. Central in the modelling work is the geological model which provides the geometrical context in terms of a model of deformation zones and the less fractured rock mass between the zones. Using the geological and geometrical description models as a basis, descriptive models for other disciplines (surface ecosystems, hydrogeology, hydrogeochemistry, rock mechanics, thermal properties and transport properties) will be developed. Great care is taken to arrive at a general consistency in the description of the various models and assessment of uncertainty and possible needs of alternative models. The main objective of this study is to support the development of a hydrogeological DFN model (Discrete Fracture Network) for the Preliminary Site Description of the Laxemar area on a regional-scale (SDM version L1.2). A more specific objective of this study is to assess the propagation of uncertainties in the geological DFN modelling reported for L1.2 into the groundwater flow modelling. An improved understanding is necessary in order to gain credibility for the Site Description in general and the hydrogeological description in particular. The latter will serve as a basis for describing the present

Hydrogeological DFN modelling using structural and hydraulic data from KLX04. Preliminary site description Laxemar subarea - version 1.2

International Nuclear Information System (INIS)

Follin, Sven; Stigsson, Martin; Svensson, Urban

2006-04-01

SKB is conducting site investigations for a high-level nuclear waste repository in fractured crystalline rocks at two coastal areas in Sweden. The two candidate areas are named Forsmark and Simpevarp. The site characterisation work is divided into two phases, an initial site investigation phase (ISI) and a complete site investigation phase (CSI). The results of the ISI phase are used as a basis for deciding on the subsequent CSI phase. On the basis of the CSI investigations a decision is made as to whether detailed characterisation will be performed (including sinking of a shaft). An integrated component in the site characterisation work is the development of site descriptive models. These comprise basic models in three dimensions with an accompanying text description. Central in the modelling work is the geological model which provides the geometrical context in terms of a model of deformation zones and the less fractured rock mass between the zones. Using the geological and geometrical description models as a basis, descriptive models for other disciplines (surface ecosystems, hydrogeology, hydrogeochemistry, rock mechanics, thermal properties and transport properties) will be developed. Great care is taken to arrive at a general consistency in the description of the various models and assessment of uncertainty and possible needs of alternative models. The main objective of this study is to support the development of a hydrogeological DFN model (Discrete Fracture Network) for the Preliminary Site Description of the Laxemar area on a regional-scale (SDM version L1.2). A more specific objective of this study is to assess the propagation of uncertainties in the geological DFN modelling reported for L1.2 into the groundwater flow modelling. An improved understanding is necessary in order to gain credibility for the Site Description in general and the hydrogeological description in particular. The latter will serve as a basis for describing the present

Groundwater movements around a repository. Geological and geotechnical conditions

International Nuclear Information System (INIS)

Stille, H.; Burgess, A.; Lindblom, U.E.

1977-09-01

The report was prepared as one of a series of technical reports within a study of the groundwater movements around a repository for radioactive waste in the Precambrian bedrock of Sweden. This assessment is intended to provide basic geotechnical data for the analysis. These data include properties and conditions that are representative of the intact rock, the rock mass in general, and the groundwater regime. As there exist a considerable range in the mineralogy of potentially suitable plutonic rocks and since a specific site has not yet been selected, all of the parameters presented in this report must be based on presumptive geological and hydrogeological conditions. Where possible, data for two potential site areas, namely Oskarshamn and Forsmark, are presented. This report is divided into four parts. First, a brief description of the procedure for modelling groundwater movements is presented, along with a tabulation of the important parameters. Secondly, a description of the geological and hydrogeological conditions of the Fennoscandian shield, as well as of the two general site areas, is given. The final two sections of the report provide thermomechanical and geohydrological characteristics and properties of the host rock

Thermal properties Forsmark. Modelling stage 2.3 Complementary analysis and verification of the thermal bedrock model, stage 2.

Energy Technology Data Exchange (ETDEWEB)

Sundberg, Jan; Wrafter, John; Laendell, Maerta (Geo Innova AB (Sweden)); Back, Paer-Erik; Rosen, Lars (Sweco AB (Sweden))

2008-11-15

This report present the results of thermal modelling work for the Forsmark area carried out during modelling stage 2.3. The work complements the main modelling efforts carried out during modelling stage 2.2. A revised spatial statistical description of the rock mass thermal conductivity for rock domain RFM045 is the main result of this work. Thermal modelling of domain RFM045 in Forsmark model stage 2.2 gave lower tail percentiles of thermal conductivity that were considered to be conservatively low due to the way amphibolite, the rock type with the lowest thermal conductivity, was modelled. New and previously available borehole data are used as the basis for revised stochastic geological simulations of domain RFM045. By defining two distinct thermal subdomains, these simulations have succeeded in capturing more of the lithological heterogeneity present. The resulting thermal model for rock domain RFM045 is, therefore, considered to be more realistic and reliable than that presented in model stage 2.2. The main conclusions of modelling efforts in model stage 2.3 are: - Thermal modelling indicates a mean thermal conductivity for domain RFM045 at the 5 m scale of 3.56 W/(mK). This is slightly higher than the value of 3.49 W/(mK) derived in model stage 2.2. - The variance decreases and the lower tail percentiles increase as the scale of observation increases from 1 to 5 m. Best estimates of the 0.1 percentile of thermal conductivity for domain RFM045 are 2.24 W/(mK) for the 1 m scale and 2.36 W/(mK) for the 5 m scale. This can be compared with corresponding values for domain RFM029 of 2.30 W/(mK) for the 1 m scale and 2.87 W/(mK)for the 5 m scale. - The reason for the pronounced lower tail in the thermal conductivity distribution for domain RFM045 is the presence of large bodies of the low-conductive amphibolite. - The modelling results for domain RFM029 presented in model stage 2.2 are still applicable. - As temperature increases, the thermal conductivity decreases

Spatial modelling of marine organisms in Forsmark and Oskarshamn. Including calculation of physical predictor variables

Energy Technology Data Exchange (ETDEWEB)

Carlen, Ida; Nikolopoulos, Anna; Isaeus, Martin (AquaBiota Water Research, Stockholm (SE))

2007-06-15

GIS grids (maps) of marine parameters were created using point data from previous site investigations in the Forsmark and Oskarshamn areas. The proportion of global radiation reaching the sea bottom in Forsmark and Oskarshamn was calculated in ArcView, using Secchi depth measurements and the digital elevation models for the respective area. The number of days per year when the incoming light exceeds 5 MJ/m2 at the bottom was then calculated using the result of the previous calculations together with measured global radiation. Existing modelled grid-point data on bottom and pelagic temperature for Forsmark were interpolated to create surface covering grids. Bottom and pelagic temperature grids for Oskarshamn were calculated using point measurements to achieve yearly averages for a few points and then using regressions with existing grids to create new maps. Phytoplankton primary production in Forsmark was calculated using point measurements of chlorophyll and irradiance, and a regression with a modelled grid of Secchi depth. Distribution of biomass of macrophyte communities in Forsmark and Oskarshamn was calculated using spatial modelling in GRASP, based on field data from previous surveys. Physical parameters such as those described above were used as predictor variables. Distribution of biomass of different functional groups of fish in Forsmark was calculated using spatial modelling based on previous surveys and with predictor variables such as physical parameters and results from macrophyte modelling. All results are presented as maps in the report. The quality of the modelled predictions varies as a consequence of the quality and amount of the input data, the ecology and knowledge of the predicted phenomena, and by the modelling technique used. A substantial part of the variation is not described by the models, which should be expected for biological modelling. Therefore, the resulting grids should be used with caution and with this uncertainty kept in mind. All

Spatial modelling of marine organisms in Forsmark and Oskarshamn. Including calculation of physical predictor variables

International Nuclear Information System (INIS)

Carlen, Ida; Nikolopoulos, Anna; Isaeus, Martin

2007-06-01

GIS grids (maps) of marine parameters were created using point data from previous site investigations in the Forsmark and Oskarshamn areas. The proportion of global radiation reaching the sea bottom in Forsmark and Oskarshamn was calculated in ArcView, using Secchi depth measurements and the digital elevation models for the respective area. The number of days per year when the incoming light exceeds 5 MJ/m2 at the bottom was then calculated using the result of the previous calculations together with measured global radiation. Existing modelled grid-point data on bottom and pelagic temperature for Forsmark were interpolated to create surface covering grids. Bottom and pelagic temperature grids for Oskarshamn were calculated using point measurements to achieve yearly averages for a few points and then using regressions with existing grids to create new maps. Phytoplankton primary production in Forsmark was calculated using point measurements of chlorophyll and irradiance, and a regression with a modelled grid of Secchi depth. Distribution of biomass of macrophyte communities in Forsmark and Oskarshamn was calculated using spatial modelling in GRASP, based on field data from previous surveys. Physical parameters such as those described above were used as predictor variables. Distribution of biomass of different functional groups of fish in Forsmark was calculated using spatial modelling based on previous surveys and with predictor variables such as physical parameters and results from macrophyte modelling. All results are presented as maps in the report. The quality of the modelled predictions varies as a consequence of the quality and amount of the input data, the ecology and knowledge of the predicted phenomena, and by the modelling technique used. A substantial part of the variation is not described by the models, which should be expected for biological modelling. Therefore, the resulting grids should be used with caution and with this uncertainty kept in mind. All

3D geological and hydrogeological modeling as design tools for the Conawapa generating station

Energy Technology Data Exchange (ETDEWEB)

Mann, J.; Sharif, S.; Smith, B. [KGS Group, Winnipeg, MB (Canada); Cook, G.N.; Osiowy, B.J. [Manitoba Hydro, Winnipeg, MB (Canada)

2008-07-01

Following the project's suspension in the early 1990s, part of Manitoba Hydro's recommitment study involved digital modeling of geological and hydrogeological data for the foundation design and analysis of the proposed Conawapa generating station in northern Manitoba. Three-dimensional geological and hydrogeological models have been developed to consolidate and improve the designer's ability to understand all of the information, and to assist in developing engineering alternatives which will improve the overall confidence of the design. The tools are also being leveraged for use in environmental studies. This paper provided an overview of the Conawapa site and 3-dimensional modeling goals. It described the geology and hydrogeology of the Conawapa site as well as the bedrock structure and Karst development. The paper also presented the central concepts of 3-dimensional modeling studies, including the flow of information from database to modeling software platforms. The construction of the Conawapa geological model was also presented, with particular reference to an overview of the MVS software; mesh design; and model buildup logic. The construction of the Conawapa hydrogeological model was discussed in terms of the finite element code FEFLOW software; conceptual model design; and initial observations of Conawapa groundwater flow modeling. It was concluded that recent advancement and application of 3-dimensional geological visualization software to engineering and environmental projects, including at the future Conawapa site using MVS and FEFLOW, have shown that complicated geological data can be organized, displayed, and analysed in a systematic way, to improve site visualization, understanding, and data relationships. 19 refs., 9 figs.

Mapping of reed in shallow bays. SFR-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Stroemgren, Maarten; Lindgren, Fredrik (Umeaa Univ. (Sweden))

2011-03-15

The regolith-lake development model (RLDM) describes the development of shallow bays to lakes and the infilling of lakes in the Forsmark area during an interglacial. The sensitivity analysis has shown the need for an update of the infill procedure in the RLDM. Data from the mapping of reed in shallow bays in the Forsmark area will be used to improve the infill procedure of an updated RLDM. The field work was performed in August 26-31, 2010. The mapping of reed was done in 124 points. In these points, coordinates and water depth were mapped using an echo sounder and a DGPS. Quaternary deposits and the thickness of soft sediments were mapped using an earth probe. Measurement points were delivered in ESRI shape format with coordinates in RT90 2.5 gon W and altitudes in the RHB70 system for storage in SKB's GIS data base

Present status and an appreciation of the consequences for recreation and outdoor leisure activities from siting a nuclear waste repository at Forsmark; Nulaegesanalys samt bedoemning av konsekvenser foer rekreation och friluftsliv av ett slutfoervar i Forsmark

Energy Technology Data Exchange (ETDEWEB)

Ottosson, Pia [Atrax Energi AB, Stockholm (Sweden)

2007-07-15

This report describes how the area around Forsmark is used with respect to recreation and outdoor life. It also describes the impact of the final repository on recreation and outdoor life if it is located in Forsmark. The studied area is situated in the parish of Forsmark in the municipality of Oesthammar. Forsmark nuclear power plant and the final repository for radioactive operational waste, SFR, are situated within the area and there are both houses and holiday houses. The area is used for leisure pursuit by inhabitants and employees at FKA and SKB, but also by a number of different associations and by tourists. Statistical data shows that the parish of Forsmark is sparsely populated. The area was previously dominated by one big landowner and the land surrounding the nuclear power plant was inaccessible to the general public during that period. The outdoor life is therefore less widespread here than along other parts of the east coast. The value of the area does not lie in paths and trails, bike tracks and bathing places, but in the unspoiled countryside, the wildlife and the bird life. Recreation such as hunting and fishing is very popular in the area. The construction of a final repository will increase traffic and hence increase noise and motion in the area. This will mainly impact the enjoyment value for the people spending time in the area. No other significant consequences are expected as the final repository will be mainly situated within the existing industrial complex and hence the character of the area should remain unchanged.

Final repository for spent nuclear fuel. Underground design Forsmark, Layout D1

International Nuclear Information System (INIS)

Brantberger, Martin; Zetterqvist, Anders; Arnbjerg-Nielsen, Torben; Olsson, Tommy; Outters, Nils; Syrjaenen, Pauli

2006-04-01

This report comprises the design step D1 related to the underground design for a deep repository located at the Forsmark site. The design is based on the Site Descriptive Model Forsmark v1.2. All studies have been focussed at an area southeast of the Forsmark nuclear plant, which has been considered to be the most promising area for hosting the repository. SKB has developed guidelines for the design of the repository, which further describes the methodology applied for the studies. From these guidelines the following basic objectives for the design step D1 are summarized: to determine whether the final repository can be accommodated within the studied site; to identify site-specific facility critical issues; to test and evaluate the design methodology; to provide feedback to: the design organisation regarding additional studies that needs to be done; the site investigation and modelling organization regarding further investigations required; and the safety assessment team. The possible locations for a tentative deep repository are analysed in Chapter 3 of the report. The most promising area for the repository (denoted 'priority site') has been defined by SKB to be located southeast of the Forsmark nuclear plant and northwest of the gently dipping deformation zone ZFMNE00A2. Regarding the repository depth, present knowledge acquired from the site investigations indicates that it is possible to locate the repository at all stipulated depths according to SKB, that is between 400 m and 700 m depth. The preliminary assessment made in Chapter 3 clearly demonstrates that the repository can be accommodated within the 'priority site'. The potential to accommodate the repository is essentially the same for both 400 m and 500 m depths. The design of the deposition areas is reported in Chapter 4, which includes the design of layout features for all tunnels and deposition holes, orientation of tunnels, calculation of anticipated loss of deposition holes due to the applied

Final repository for spent nuclear fuel. Underground design Forsmark, Layout D1

Energy Technology Data Exchange (ETDEWEB)

Brantberger, Martin; Zetterqvist, Anders [Ramboell Sweden AB, Stockholm (Sweden); Arnbjerg-Nielsen, Torben [Ramboell Denmark A/S, Virum (Denmark); Olsson, Tommy [IandT Olsson AB, Uppsala (Sweden); Outters, Nils [Golder Associates AB, Uppsala (Sweden); Syrjaenen, Pauli [Gridpoint Oy, Helsinki (Sweden)

2006-04-15

This report comprises the design step D1 related to the underground design for a deep repository located at the Forsmark site. The design is based on the Site Descriptive Model Forsmark v1.2. All studies have been focussed at an area southeast of the Forsmark nuclear plant, which has been considered to be the most promising area for hosting the repository. SKB has developed guidelines for the design of the repository, which further describes the methodology applied for the studies. From these guidelines the following basic objectives for the design step D1 are summarized: to determine whether the final repository can be accommodated within the studied site; to identify site-specific facility critical issues; to test and evaluate the design methodology; to provide feedback to: the design organisation regarding additional studies that needs to be done; the site investigation and modelling organization regarding further investigations required; and the safety assessment team. The possible locations for a tentative deep repository are analysed in Chapter 3 of the report. The most promising area for the repository (denoted 'priority site') has been defined by SKB to be located southeast of the Forsmark nuclear plant and northwest of the gently dipping deformation zone ZFMNE00A2. Regarding the repository depth, present knowledge acquired from the site investigations indicates that it is possible to locate the repository at all stipulated depths according to SKB, that is between 400 m and 700 m depth. The preliminary assessment made in Chapter 3 clearly demonstrates that the repository can be accommodated within the 'priority site'. The potential to accommodate the repository is essentially the same for both 400 m and 500 m depths. The design of the deposition areas is reported in Chapter 4, which includes the design of layout features for all tunnels and deposition holes, orientation of tunnels, calculation of anticipated loss of deposition holes due

The World's Reactors no. 70 - Forsmark 3, BWR-75

International Nuclear Information System (INIS)

Anon.

1976-01-01

A large pull-out wall chart is presented showing a coloured cut-away diagram of the Forsmark 3 station. It is accompanied by 2 small sketches one showing the layout of station buildings and the other the inside of the reactor vessel. Parameters are listed. (U.K.)

Geophysical and hydrogeological characterisation of the impacts of on-site wastewater treatment discharge to groundwater in a poorly productive bedrock aquifer

Energy Technology Data Exchange (ETDEWEB)

Donohue, Shane [School of Planning, Architecture and Civil Engineering, Queen' s University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, Northern Ireland (United Kingdom); McCarthy, Valerie; Rafferty, Patrick [Department of Applied Sciences, Dundalk Institute of Technology, Dublin Road, Dundalk (Ireland); Orr, Alison; Flynn, Raymond [School of Planning, Architecture and Civil Engineering, Queen' s University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, Northern Ireland (United Kingdom)

2015-08-01

Contaminants discharging from on-site wastewater treatment systems (OSWTSs) can impact groundwater quality, threatening human health and surface water ecosystems. Risk of negative impacts becomes elevated in areas of extreme vulnerability with high water tables, where thin unsaturated intervals limit vadose zone attenuation. A combined geophysical/hydrogeological investigation into the effects of an OSWTS, located over a poorly productive aquifer (PPA) with thin subsoil cover, aimed to characterise effluent impacts on groundwater. Groundwater, sampled from piezometers down-gradient of the OSWTS percolation area displayed spatially erratic, yet temporally consistent, contaminant distributions. Electrical resistivity tomography identified an area of gross groundwater contamination close to the percolation area and, when combined with seismic refraction and water quality data, indicated that infiltrating effluent reaching the water table discharged to a deeper more permeable zone of weathered shale resting on more competent bedrock. Subsurface structure, defined by geophysics, indicated that elevated chemical and microbiological contaminant levels encountered in groundwater samples collected from piezometers, down-gradient of sampling points with lower contaminant levels, corresponded to those locations where piezometers were screened close to the weathered shale/competent rock interface; those immediately up-gradient were too shallow to intercept this interval, and thus the more impacted zone of the contaminant plume. Intermittent occurrence of faecal indicator bacteria more than 100 m down gradient of the percolation area suggested relatively short travel times. Study findings highlight the utility of geophysics as part of multidisciplinary investigations for OSWTS contaminant plume characterisation, while also demonstrating the capacity of effluent discharging to PPAs to impact groundwater quality at distance. Comparable geophysical responses observed in similar

Geophysical and hydrogeological characterisation of the impacts of on-site wastewater treatment discharge to groundwater in a poorly productive bedrock aquifer

International Nuclear Information System (INIS)

Donohue, Shane; McCarthy, Valerie; Rafferty, Patrick; Orr, Alison; Flynn, Raymond

2015-01-01

Contaminants discharging from on-site wastewater treatment systems (OSWTSs) can impact groundwater quality, threatening human health and surface water ecosystems. Risk of negative impacts becomes elevated in areas of extreme vulnerability with high water tables, where thin unsaturated intervals limit vadose zone attenuation. A combined geophysical/hydrogeological investigation into the effects of an OSWTS, located over a poorly productive aquifer (PPA) with thin subsoil cover, aimed to characterise effluent impacts on groundwater. Groundwater, sampled from piezometers down-gradient of the OSWTS percolation area displayed spatially erratic, yet temporally consistent, contaminant distributions. Electrical resistivity tomography identified an area of gross groundwater contamination close to the percolation area and, when combined with seismic refraction and water quality data, indicated that infiltrating effluent reaching the water table discharged to a deeper more permeable zone of weathered shale resting on more competent bedrock. Subsurface structure, defined by geophysics, indicated that elevated chemical and microbiological contaminant levels encountered in groundwater samples collected from piezometers, down-gradient of sampling points with lower contaminant levels, corresponded to those locations where piezometers were screened close to the weathered shale/competent rock interface; those immediately up-gradient were too shallow to intercept this interval, and thus the more impacted zone of the contaminant plume. Intermittent occurrence of faecal indicator bacteria more than 100 m down gradient of the percolation area suggested relatively short travel times. Study findings highlight the utility of geophysics as part of multidisciplinary investigations for OSWTS contaminant plume characterisation, while also demonstrating the capacity of effluent discharging to PPAs to impact groundwater quality at distance. Comparable geophysical responses observed in similar

Design of a groundwater sampling network for Minnesota

International Nuclear Information System (INIS)

Kanivetsky, R.

1977-01-01

This folio was compiled to facilitate the use of groundwater as a sampling medium to aid in exploration for hitherto undiscovered deposits of uranium in the subsurface rocks of Minnesota. The report consists of the following sheets of the hydrogeologic map of Minnesota: (1) map of bedrock hydrogeology, (2) generalized cross sections of the hydrogeologic map of Minnesota, showing both Quaternary deposits and bedrock, (3) map of waterwells that penetrate Precambrian rocks in Minnesota. A list of these wells, showing locations, names of owners, type of Precambrian aquifers penetrated, lithologic material of the aquifers, and well depths is provided in the appendix to this report. Structural settings, locations, and composition of the bedrock aquifers, movement of groundwater, and preliminary suggestions for a sampling program are discussed below under the heading Bedrock Hydrogeology of Minnesota. The map sheet showing Quaternary hydrogeology is not included in this report because the chemistry of groundwater in these deposits is not directly related to bedrock mineralization

Final disposal of spent nuclear fuel in Finnish bedrock - Romuvaara site report

Energy Technology Data Exchange (ETDEWEB)

Anttila, P. [Fortum Engineering Oy (Finland); Ahokas, H. [Fintact Oy (Finland); Front, K. [VTT Communities and Infrastructure, Espoo (Finland)] [and others

1999-06-01

most evolved groundwaters are found in borehole KR3 with a TDS value of 265 mg/l and a chloride content of 109 mg/l. Reducing conditions are expected to exist at depth, which are favourable in terms of low radionuclide solubility and slow canister corrosion. Potentially suitable bedrock blocks have been identified at the site for locating a repository for spent fuel in the depth range of 400 - 700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones should be avoided when locating the deposition tunnels and disposal holes. (orig.) 254 refs.

Final disposal of spent nuclear fuel in Finnish bedrock - Romuvaara site report

International Nuclear Information System (INIS)

Anttila, P.; Ahokas, H.; Front, K.

1999-06-01

groundwaters are found in borehole KR3 with a TDS value of 265 mg/l and a chloride content of 109 mg/l. Reducing conditions are expected to exist at depth, which are favourable in terms of low radionuclide solubility and slow canister corrosion. Potentially suitable bedrock blocks have been identified at the site for locating a repository for spent fuel in the depth range of 400 - 700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones should be avoided when locating the deposition tunnels and disposal holes. (orig.)

Flow in bedrock canyons.

Science.gov (United States)

Venditti, Jeremy G; Rennie, Colin D; Bomhof, James; Bradley, Ryan W; Little, Malcolm; Church, Michael

2014-09-25

Bedrock erosion in rivers sets the pace of landscape evolution, influences the evolution of orogens and determines the size, shape and relief of mountains. A variety of models link fluid flow and sediment transport processes to bedrock incision in canyons. The model components that represent sediment transport processes are increasingly well developed. In contrast, the model components being used to represent fluid flow are largely untested because there are no observations of the flow structure in bedrock canyons. Here we present a 524-kilometre, continuous centreline, acoustic Doppler current profiler survey of the Fraser Canyon in western Canada, which includes 42 individual bedrock canyons. Our observations of three-dimensional flow structure reveal that, as water enters the canyons, a high-velocity core follows the bed surface, causing a velocity inversion (high velocities near the bed and low velocities at the surface). The plunging water then upwells along the canyon walls, resulting in counter-rotating, along-stream coherent flow structures that diverge near the bed. The resulting flow structure promotes deep scour in the bedrock channel floor and undercutting of the canyon walls. This provides a mechanism for channel widening and ensures that the base of the walls is swept clear of the debris that is often deposited there, keeping the walls nearly vertical. These observations reveal that the flow structure in bedrock canyons is more complex than assumed in the models presently used. Fluid flow models that capture the essence of the three-dimensional flow field, using simple phenomenological rules that are computationally tractable, are required to capture the dynamic coupling between flow, bedrock erosion and solid-Earth dynamics.

Applicability of reflection seismic measurements in detailed characterization of crystalline bedrock

International Nuclear Information System (INIS)

Sireni, S.

2011-03-01

Posiva carried out a seismic survey in the access tunnel of the underground research facility ONKALO in 2009. The survey contributes the detailed characterization of the bedrock in the final disposal of spent nuclear fuel. The aim of this work was to examine the geophysical and geological properties of the chosen tunnel intersections to clarify the important characteristics for reflection generation, and evaluate applicability of this survey for characterization of crystalline bedrock. The seismic result consists of 24 projected amplitude images in 12 different angles. The size of an image is 260*300 m. The amount of digitized reflectors is over 100 and all of them could not be included in this work. The study was limited to 14 intersections that were considered important: brittle fault intersections, tunnel-crosscutting fractures, or lithological contacts. Presence of a brittle fault zone or a tunnel-crosscutting fracture limits the suitable bedrock volume for depositing the nuclear fuel canisters, and wide lithological contacts are a common source of reflection. The seismic data was compared to the existing geological, hydrogeological and geophysical data got from the pilot holes and the tunnel. The most important characteristics were fractures: orientation, fillings, and thickness of the fillings, alteration and water leakage. Geophysically interesting was density, seismic velocities and their products: acoustic impedance and synthetic seismograms. Calculated acoustic impedances showed some differences between cases, but they did not indicate the presence of a reflector. The most common cause of reflector was undulating slickensided, highly altered, tunnel-crosscutting fracture that had thick fracture-fillings and water present. Water was included five times in interpreted reflectors. Also few reflectors were connected to varying mineralogy. Few problematic cases occurred, where a geological feature and a reflection did not correlate, and three of the cases with

Modelling transport of water and solutes in future wetlands in Forsmark

Energy Technology Data Exchange (ETDEWEB)

Vikstroem, Maria; Gustafsson, Lars-Goeran [DHI Water and Environment AB, Vaexjoe (Sweden)

2006-03-15

The Forsmark area consists of a number of natural wetlands. As a part of the evaluation of wetlands in the safety assessment for the area, possible future wetlands are being studied with respect to hydrology and transport mechanisms. A sensitivity analyses is performed to point out the governing parameters for the wetland hydraulics. The analysis of future wetlands is carried out using the hydrological model system Mike SHE. Mike SHE has been used to describe the near-surface hydrology for a regional model area in Forsmark. Three types of areas have been chosen. Today's lake Bolundfjaerden is because of its shallow depth likely to develop into a mire in the future. As it is situated in the downstream part of the regional model area, the runoff to the lake from upstream surface water system is significant. Lake Eckarfjaerden is situated in the upstream part of the catchment at a higher altitude and with a smaller inflow. Lake Puttan is situated above a planned layout of the repository and has a potential to receive discharges from a repository. It also lies in the downstream part of a large discharge area. The topography of the future mires is assumed to be flat, up to today's mean water level in each lake. To transport the surface runoff through the wetland, streams or water courses are assumed to form within the peat. The analyses of future wetlands in the Forsmark area show that the hydraulic conditions that exists today will somewhat alter as the peat is formed. For Bolundsfjaerden, where there during present conditions are weak discharge areas, a recharge area has formed during the summer. This can be explained by the amount of surface water that forms on the surface which increases the head elevation in the upper soil layers. The same holds for Eckarfjaerden, while Puttan after the peat has developed still is a discharge area due to its naturally strong discharge position close to the sea. Different vegetation and development stages for the peat have

Modelling transport of water and solutes in future wetlands in Forsmark

International Nuclear Information System (INIS)

Vikstroem, Maria; Gustafsson, Lars-Goeran

2006-03-01

The Forsmark area consists of a number of natural wetlands. As a part of the evaluation of wetlands in the safety assessment for the area, possible future wetlands are being studied with respect to hydrology and transport mechanisms. A sensitivity analyses is performed to point out the governing parameters for the wetland hydraulics. The analysis of future wetlands is carried out using the hydrological model system Mike SHE. Mike SHE has been used to describe the near-surface hydrology for a regional model area in Forsmark. Three types of areas have been chosen. Today's lake Bolundfjaerden is because of its shallow depth likely to develop into a mire in the future. As it is situated in the downstream part of the regional model area, the runoff to the lake from upstream surface water system is significant. Lake Eckarfjaerden is situated in the upstream part of the catchment at a higher altitude and with a smaller inflow. Lake Puttan is situated above a planned layout of the repository and has a potential to receive discharges from a repository. It also lies in the downstream part of a large discharge area. The topography of the future mires is assumed to be flat, up to today's mean water level in each lake. To transport the surface runoff through the wetland, streams or water courses are assumed to form within the peat. The analyses of future wetlands in the Forsmark area show that the hydraulic conditions that exists today will somewhat alter as the peat is formed. For Bolundsfjaerden, where there during present conditions are weak discharge areas, a recharge area has formed during the summer. This can be explained by the amount of surface water that forms on the surface which increases the head elevation in the upper soil layers. The same holds for Eckarfjaerden, while Puttan after the peat has developed still is a discharge area due to its naturally strong discharge position close to the sea. Different vegetation and development stages for the peat have been

Propagation characteristics of bedrock waves traveling from pre-Tertiary basement to engineering bedrock

Science.gov (United States)

Kinoshita, S.

2007-11-01

This study uses borehole array recordings to measure the propagation characteristics of bedrock waves traveling from pre-Tertiary basement (seismic bedrock) to engineering bedrock with an S-wave velocity of approximately 0.5-0.8 km/s. To avoid the destructive interference of surface-reflected down-going waves and incidence waves in seismic and engineering bedrock, borehole data recorded at sufficient depth levels are used in this study. This is the most important aspect of the fundamental basis of this study. The propagation characteristics, i.e., the transfer function, of bedrock motions for S-waves are well represented by a Butterworth-type low-pass filter model with a high corner frequency in excess of 15 Hz and a low decay rate of -3 power of frequency. The use of such a filter model is based on the concise representation of the transfer function from an engineering viewpoint. Simple one-dimensional ray theory with a plane wave approximation explains the characteristics of the model filter at low frequencies of less than approximately 5 Hz; however, one-dimensional ray theory with a plane wave approximation at high frequencies in excess of 5 Hz requires the unusual frequency characteristics of Q_S-1(f), which increases with increasing frequency, to explain the frequency characteristics of the model filter. These facts imply that the filter gain can be determined using the impedance ratio of seismic bedrock to engineering bedrock and the attenuation characteristics of the intervening media at low frequencies less than 5 Hz. However, the cutoff frequency and decay rate of the filter must be determined from observational data.

Hydrogeology and simulation of ground-water flow in the Silurian-Devonian aquifer system, Johnson County, Iowa

Science.gov (United States)

Tucci, Patrick; McKay, Robert M.

2006-01-01

Bedrock of Silurian and Devonian age (termed the “Silurian-Devonian aquifer system”) is the primary source of ground water for Johnson County in east-central Iowa. Population growth within municipal and suburban areas of the county has resulted in increased amounts of water withdrawn from this aquifer and water-level declines in some areas. A 3-year study of the hydrogeology of the Silurian-Devonian aquifer system in Johnson County was undertaken to provide a quantitative assessment of ground water resources and to construct a ground-water flow model that can be used by local governmental agencies as a management tool.

Impact assessment of the impact on nature values of the construction and operation of the repository for spent nuclear fuel at Forsmark; Konsekvensbedoemning av paaverkan paa naturvaerden av anlaeggande och drift av slutfoervar foer anvaent kaernbraensle i Forsmark

Energy Technology Data Exchange (ETDEWEB)

Allmer, Johan (Ekologigruppen AB, Stockholm (Sweden))

2011-03-15

Construction and operation of a repository at Soederviken in Forsmark, Oesthammar municipality means impact, effects and consequences for the environment. This report describes the natural conditions and natural values in Forsmark with particular focus on Soederviken. Furthermore, an assessment of consequences for the natural environment in the development and operation of a repository at Soederviken. Assessment of impacts from water activities are treated in a special report.

Hydrogeologic framework of fractured sedimentary rock, Newark Basin, New Jersey

Science.gov (United States)

Lacombe, Pierre J.; Burton, William C.

2010-01-01

The hydrogeologic framework of fractured sedimentary bedrock at the former Naval Air Warfare Center (NAWC), Trenton, New Jersey, a trichloroethylene (TCE)-contaminated site in the Newark Basin, is developed using an understanding of the geologic history of the strata, gamma-ray logs, and rock cores. NAWC is the newest field research site established as part of the U.S. Geological Survey Toxic Substances Hydrology Program, Department of Defense (DoD) Strategic Environmental Research and Development Program, and DoD Environmental Security Technology Certification Program to investigate contaminant remediation in fractured rock. Sedimentary bedrock at the NAWC research site comprises the Skunk Hollow, Byram, and Ewing Creek Members of the Lockatong Formation and Raven Rock Member of the Stockton Formation. Muds of the Lockatong Formation that were deposited in Van Houten cycles during the Triassic have lithified to form the bedrock that is typical of much of the Newark Basin. Four lithotypes formed from the sediments include black, carbon-rich laminated mudstone, dark-gray laminated mudstone, light-gray massive mudstone, and red massive mudstone. Diagenesis, tectonic compression, off-loading, and weathering have altered the rocks to give some strata greater hydraulic conductivity than other strata. Each stratum in the Lockatong Formation is 0.3 to 8 m thick, strikes N65 degrees E, and dips 25 degrees to 70 degrees NW. The black, carbon-rich laminated mudstone tends to fracture easily, has a relatively high hydraulic conductivity and is associated with high natural gamma-ray count rates. The dark-gray laminated mudstone is less fractured and has a lower hydraulic conductivity than the black carbon-rich laminated mudstone. The light-gray and the red massive mudstones are highly indurated and tend to have the least fractures and a low hydraulic conductivity. The differences in gamma-ray count rates for different mudstones allow gamma-ray logs to be used to correlate and

Forsmark site investigation. Detailed ground magnetic survey and lineament interpretation in the Forsmark area, 2006-2007

International Nuclear Information System (INIS)

Isaksson, Hans; Thunehed, Hans; Pitkaenen, Timo; Keisu, Mikael

2007-12-01

The report presents detailed ground magnetic measurements carried out on an 11.1 km 2 area in the Forsmark site investigation area. The main objective of this activity is to determine a detailed ground magnetic representation of the bedrock. The results from previous surveys were encouraging and have led to a broad geophysical programme for investigation of lineaments at Forsmark. This report comprises the results from the second and final phase of the extended survey programme and a compilation and summary of all phases in the programme. On ground and on lake ice, a grid with parallel lines was staked. Measurements of the magnetic total field were carried out along profiles, perpendicular to the staked lines, with a profile spacing of 10 m and a station spacing of 5 m. Measurements on the ice-covered sea bays were carried out by a two man crew. One crew member walked along the survey lines, carrying a RTK-GPS guiding the other crew member who measured the magnetic total field. No seaborne survey was carried out in the final phase. Previously, using a high accuracy RTK-GPS unit for boat navigation gave a seaborne survey grid of on average 10 m line spacing and 2-3 m station spacing. In total 427,238 magnetic survey stations have been measured and an area of 4.7 km 2 has been surveyed from boat. The magnetic pattern in the survey area can be divided into six main areas with different magnetic character. Along the southwest margin of the survey area the magnetic pattern is intensely banded with rapidly changing low and highly magnetic bands striking southeast-northwest, which to the northeast changes to a gentler, banded pattern of low to moderate magnetic intensity. To the northeast, at the SFR office and along the coastline to the southeast, the pattern is again intensely banded with, southeast-northwest trending, rapidly changing low and highly magnetic bands. These two banded structures probably forms fold limbs of a common fold with a northwest oriented fold

Hydrogeological study

International Nuclear Information System (INIS)

Massa, E.; Heinzen, W.; Santana, J.

1987-01-01

This work shows the hydrogeological study and well drilling carried out in the Teaching Formation Institute San Jose de Mayo Province Uruguay. It was developed a geological review in the National Directorate of Geology and Mining data base as well as field working, geology and hydrogeology recognition and area well drilling inventory.

Monitoring Forsmark. Bird monitoring in Forsmark 2010

Energy Technology Data Exchange (ETDEWEB)

Green, Martin (Dept. of Animal Ecology, Lund Univ. (Sweden))

2010-12-15

This report summarizes the monitoring of selected listed (Swedish Red List and/or the EU Birds Directive) breeding birds in Forsmark 2002-2010. Monitoring of eleven listed species was conducted in the regional model area, including the candidate area in 2010 in the same way as in earlier years. The results from the monitoring in 2010 differed somewhat from results gathered in earlier years. Most monitored species have increased in local numbers during the study years, and from most years continued increases have been reported. Between 2009 and 2010 most species (seven, 64% of the monitored ones) instead decreased in numbers. Only one species (honey buzzard) increased in numbers between the years and in this case this was probably more a result of small moves by certain pairs so that they this year had parts reaching into the regional model area, while in 2009 their territories were outside of this. No dramatic changes in bird numbers were however recorded and all the studied species show stable or increasing local populations over the study period. Number of Black-throated diver pairs was normal and breeding success was good this year. The breeding success of divers has improved considerably over the studied period and the patterns recorded in Forsmark closely follow recorded patterns at the national level. Honey buzzards and ospreys occurred in good numbers, above the average for the whole period, and breeding success was better than in 2009. Even if breeding success of honey buzzards is not monitored in any detail, there were still signs of at least a few successful breedings in the area this year. Breeding success of ospreys was below average, but still within the normal variation for most years. The local white-tailed eagles had a poor breeding season and no young at all were produced within the study area. All three grouse species (black grouse, capercaillie and hazelhen) decreased in numbers between 2009 and 2010. Note however that the large amounts of snow

Monitoring Forsmark. Bird monitoring in Forsmark 2010

International Nuclear Information System (INIS)

Green, Martin

2010-12-01

This report summarizes the monitoring of selected listed (Swedish Red List and/or the EU Birds Directive) breeding birds in Forsmark 2002-2010. Monitoring of eleven listed species was conducted in the regional model area, including the candidate area in 2010 in the same way as in earlier years. The results from the monitoring in 2010 differed somewhat from results gathered in earlier years. Most monitored species have increased in local numbers during the study years, and from most years continued increases have been reported. Between 2009 and 2010 most species (seven, 64% of the monitored ones) instead decreased in numbers. Only one species (honey buzzard) increased in numbers between the years and in this case this was probably more a result of small moves by certain pairs so that they this year had parts reaching into the regional model area, while in 2009 their territories were outside of this. No dramatic changes in bird numbers were however recorded and all the studied species show stable or increasing local populations over the study period. Number of Black-throated diver pairs was normal and breeding success was good this year. The breeding success of divers has improved considerably over the studied period and the patterns recorded in Forsmark closely follow recorded patterns at the national level. Honey buzzards and ospreys occurred in good numbers, above the average for the whole period, and breeding success was better than in 2009. Even if breeding success of honey buzzards is not monitored in any detail, there were still signs of at least a few successful breedings in the area this year. Breeding success of ospreys was below average, but still within the normal variation for most years. The local white-tailed eagles had a poor breeding season and no young at all were produced within the study area. All three grouse species (black grouse, capercaillie and hazelhen) decreased in numbers between 2009 and 2010. Note however that the large amounts of snow

Analysis of overdeepened valleys using the digital elevation model of the bedrock surface of Northern Switzerland

Energy Technology Data Exchange (ETDEWEB)

Jordan, P.

2010-11-15

Based on surface and borehole information, together with pre-existing regional and local interpretations, a 7,150 square kilometre Raster Digital Elevation Model (DEM) of the bedrock surface of northern Switzerland was constructed using a 25 m cell size. This model represents a further important step in the understanding of Quaternary sediment distribution and is open to a broad field of application and analysis, including hydrogeological, geotechnical and geophysical studies as well as research in the field of Pleistocene landscape evolution. An analysis of the overdeepened valleys in the whole model area and, more specifically in the Reuss area, shows that, in most cases, overdeepening is restricted to the areas covered by the Last Glaciation Maximum (LGM). However, at various locations relatively narrow overdeepened valleys outreach the tongue basins and the LGM ice shield limits. Therefore, an earlier and further-reaching glacial event has probably contributed significantly to the overdeepening of these valleys. No significant overdeepening has been identified downstream of Boettstein (Aare) and Kaiserstuhl (Rhine), although the ice extended considerably further downstream, at least during the most extensive glaciation. Except for the bedrock between Brugg and Boettstein, no overdeepened valleys are found significantly north of the outcrop of Mesozoic limestone of the Folded and Tabular Jura. A detailed analysis of the Reuss area shows that the Lake and Suhre valleys are separated from the Emmen-Gisikon Reuss valley basin by a significant bedrock barrier. The individual bedrock valleys are divided into several sub-basins, indicating a multiphase evolution of the valleys. Some of the swells or barriers separating the sub-basins coincide with known late LGM retreat stages. In the Suhre valley, an old fluvial valley floor with restricted overdeepened sections is documented. (author)

Bedrock Geology of the DFDP-2 Drill-Site

Science.gov (United States)

Toy, V.; Sutherland, R.; Townend, J.

2015-12-01

Bedrock was encountered in DFDP-2B at drilled depths (MD) of 238.50-893.18 m (vertical depths of 238.40-818.00 m). Continuous sampling of cuttings revealed the bedrock is composed predominantly of ductilely sheared mylonite-series lithologies exhumed from the roots of the Alpine Fault zone. The protolith is interpreted to be amphibolite facies metasediments classified as part of the Aspiring Subdivision of the Torlesse Supergroup. Onsite description of whole cuttings and thin sections made within a few hours of sample recovery allowed identification of progressive structural changes. Fabrics were schistose in the upper part of the hole, but at greater depths we observed increasing indications that the rocks had been subjected to simple shear deformation. These macro-and micro-structural features are consistent with those that typify the Alpine Fault mylonite sequence previously described, and were used as input to drilling decisions. The structural features found to be the most useful indicators of ductile simple shear strain accommodated by the recovered rocks were the occurrence of shear bands; changes in mean quartz grain size; changes in maximum mica grain size; and redistribution of or changes in microstructural setting of accessory phases (e.g. graphite). The quartz:mica ratio based on mass was also determined but the extent to which this reflects true lithologic variations is unclear, as washing and winnowing of the samples (both by circulating drill fluids and during the sample collection process) probably modified bulk mineralogy in different particle size domains. Nevertheless, the quartz:mica dataset suggests a dramatic change in mineralogy at 730 m MD (vertical depth of 695 m). This coincides with a pronounced step in the temperature gradient, possibly related to large changes in hydrogeology.

Inventory of mammals at Forsmark and Haallnaes; Inventering av daeggdjur i Forsmark och Haallnaes

Energy Technology Data Exchange (ETDEWEB)

Truve, Johan [Svensk Naturfoervaltning AB, Goeteborg (Sweden)

2012-08-15

A selection of terrestrial mammals was surveyed in the SKB site investigation areas near Forsmark and Haallnaes between January and April 2012. The methods that were used include snow tracking along line transects, snow tracking along water, aerial survey and fecal pellet counts. The same species were found in 2012 as in previous surveys performed in 2002, 2003 and 2007. Some species show a large variation in density between years and it is difficult to draw any conclusions about their long term development. Several carnivores, i.e. lynx, fox and otter show a positive growth rate in both areas. The wild boar population is also growing whilst moose density remains fairly stable and roe deer are becoming less numerous.

Groundwater chemical changes at SFR in Forsmark

Energy Technology Data Exchange (ETDEWEB)

Laaksoharju, Marcus [GeoPoint AB, Sollentuna (Sweden); Gurban, Ioana [3DTerra (Sweden)

2003-01-01

The examination of the groundwater sampled at the SFR tunnel system indicated that the groundwater consist mainly of a Na-Cl to Na-Ca-Cl type of water. Most of the samples fall within the Cl range of 2500-5500 mg/l having a neutral pH (6.6-7.7 units). The water is reducing and despite the fact that the tunnel acts like a hydraulic sink constantly withdrawing water out from the rock into the tunnel the groundwater changes are moderate with time. Most of the sampling points in the SFR tunnel system are located under the Sea and M3 calculations indicated that most of the sampling points have a change of water types from an older marine water type affected by glacial melt water to an more modern marine water type such as Baltic Sea water which has been modified by possibly microbial sulphate reduction and ion exchange. Mass balance calculations indicated that the waters seem to be in equilibrium with the fracture filling mineral such as calcite. The quality of the aluminium data made the modelling with the major rock forming aluminium silicates such as feldspars and clay minerals uncertain and was therefore not reported. The conclusion is that the groundwater evolution and patterns at SFR are a result of many factors such as: 1. the changes in hydrogeology related to glaciation/deglaciation and land uplift, 2. repeated Sea/lake water regressions/transgressions 3. the closeness to Baltic Sea resulting in relative small hydrogeological driving forces which could preserve old water types from being flushed out, 4. organic or inorganic alteration of the groundwater caused by microbial processes or in situ water/rock interactions 5. tunnel construction which changed the flow system The modelled present-day groundwater conditions of the SFR site consist of a mixture in varying degrees of different water types. The data indicate that all the groundwater at SFR is strongly affected by Sea water of different origin and ages. The meteoric (0- 1000 B.P) portion is located close

Water activities in Forsmark. Ecological field inventory and classification of biodiversity values and description of forest production land

International Nuclear Information System (INIS)

Hamren, Ulrika; Collinder, Per

2010-12-01

In 2009, the Swedish Nuclear Fuel and Waste Management Co (SKB) chose Forsmark in the Municipality of Oesthammar as site for the final repository for spent nuclear fuel. This report describes nature values and forestry areas in Forsmark, and provides part of the background material for description of consequences due to groundwater diversion during construction and operation of the repository. The report describes results of map studies and comprehensive field investigations, in terms of geographical delineations, descriptions of characteristics and classifications of nature values for groundwater dependent or groundwater favoured nature objects in Forsmark. The nature objects are located in an investigation area, which contains the area that according to numerical flow modelling could be affected by groundwater-table drawdown due to groundwater diversion

Hydrogeology of Virginia

Science.gov (United States)

Nelms, David L.; Harlow, George; Bruce, T. Scott; Bailey, Christopher M.; Sherwood, W. Cullen; Eaton, L. Scott; Powars, David S.

2016-01-01

The hydrogeology of Virginia documented herein is in two parts. Part 1 consists of an overview and description of the hydrogeology within each regional aquifer system in the Commonwealth. Part 2 includes discussions of hydrogeologic research topics of current relevance including: 1. the Chesapeake Bay impact structure, 2. subsidence/compaction in the Coastal Plain, 3. groundwater age and aquifer susceptibility, 4. the occurrence of groundwater at depth in fractured-rock and karst terrains, and 5. hydrologic response of wells to earthquakes around the world.

Soil carbon effluxes in ecosystems of Forsmark and Laxemar

Energy Technology Data Exchange (ETDEWEB)

Tagesson, Torbern (Dept. of Physical Geography and Ecosystem Analysis, Lund Univ. (Sweden))

2007-12-15

Soil carbon effluxes were estimated in a number of ecosystems in Laxemar and Forsmark investigations areas. It was done in a young Scots pine (Pinus sylvestris) stand, a wet deciduous stand, a poor fen and an agricultural field in the Laxemar investigation area in south-eastern Sweden (57 deg 5 min N, 16 deg 7 min E) and in a pasture, two Norway spruce (Picea abies) stands, a deciduous forest, a mire, a wet deciduous forest and a clear-cut in the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). It was measured with the closed chamber technique in 2005 and 2006. Soil temperature at 10 cm depth, air temperature and photosynthetically active radiation (PAR) were also measured. Exponential regressions with soil respiration against air and soil temperature were used to estimate annual soil respiration. A hyperbolic curve with Gross Primary Production (GPP) against PAR was used for modelling GPP for the growing season in the poor fen and the agricultural area of Laxemar. The exponential regressions with soil respiration against air and soil temperature explained on average 33.6% and 44.0% of the variation, respectively. GPP of the ground vegetation were reducing soil carbon effluxes, in all stands but one of the spruce stands, the deciduous forest, the mire and the wet deciduous forest of Forsmark. The significant (all but spruce 2 in Forsmark) curves with GPP against PAR explained on average 22.7% of the variation in GPP. The cubic regressions with GPP against air temperature were only significant for the poor fen and the agricultural field in Laxemar and it explained on average 34.8% of the variation in GPP for these ecosystems. The exponential regressions with air and soil temperature against soil respiration could be used to temporally extrapolate the occasional field measurements. The hyperbolic curve with GPP against PAR could also be used for temporal extrapolation of GPP for the ecosystems without a tree layer, i.e. the poor fen and the agricultural

Soil carbon effluxes in ecosystems of Forsmark and Laxemar

International Nuclear Information System (INIS)

Tagesson, Torbern

2007-12-01

Soil carbon effluxes were estimated in a number of ecosystems in Laxemar and Forsmark investigations areas. It was done in a young Scots pine (Pinus sylvestris) stand, a wet deciduous stand, a poor fen and an agricultural field in the Laxemar investigation area in south-eastern Sweden (57 deg 5 min N, 16 deg 7 min E) and in a pasture, two Norway spruce (Picea abies) stands, a deciduous forest, a mire, a wet deciduous forest and a clear-cut in the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). It was measured with the closed chamber technique in 2005 and 2006. Soil temperature at 10 cm depth, air temperature and photosynthetically active radiation (PAR) were also measured. Exponential regressions with soil respiration against air and soil temperature were used to estimate annual soil respiration. A hyperbolic curve with Gross Primary Production (GPP) against PAR was used for modelling GPP for the growing season in the poor fen and the agricultural area of Laxemar. The exponential regressions with soil respiration against air and soil temperature explained on average 33.6% and 44.0% of the variation, respectively. GPP of the ground vegetation were reducing soil carbon effluxes, in all stands but one of the spruce stands, the deciduous forest, the mire and the wet deciduous forest of Forsmark. The significant (all but spruce 2 in Forsmark) curves with GPP against PAR explained on average 22.7% of the variation in GPP. The cubic regressions with GPP against air temperature were only significant for the poor fen and the agricultural field in Laxemar and it explained on average 34.8% of the variation in GPP for these ecosystems. The exponential regressions with air and soil temperature against soil respiration could be used to temporally extrapolate the occasional field measurements. The hyperbolic curve with GPP against PAR could also be used for temporal extrapolation of GPP for the ecosystems without a tree layer, i.e. the poor fen and the agricultural

Regional hydrogeological simulations. Numerical modelling using ConnectFlow. Preliminary site description Simpevarp sub area - version 1.2

Energy Technology Data Exchange (ETDEWEB)

Hartley, Lee; Hoch, Andrew; Hunter, Fiona; Jackson, Peter [Serco Assurance, Risley (United Kingdom); Marsic, Niko [Kemakta Konsult, Stockholm (Sweden)

2005-02-01

The Swedish Nuclear Fuel and Waste Management Company (SKB) carries out site investigations in two different candidate areas in Sweden with the objective of describing the in situ conditions for a bedrock repository for spent nuclear fuel. The two candidate areas are named Forsmark and Simpevarp. The site characterisation work is divided into two phases, an initial site investigation phase (IPLU) and a complete site investigation phase (KPLU). The results of IPLU are used as a basis for deciding on a subsequent KPLU phase. On the basis of the KPLU investigations a decision is made as to whether detailed characterisation will be performed (including sinking of a shaft).An integrated component in the site characterisation work is the development of site descriptive models. These comprise basic models in three dimensions with an accompanying text description. Central in the modelling work is the geological model which provides the geometrical context in terms of a model of deformation zones and the rock mass between the zones. Using the geological and geometrical description models as a basis, descriptive models for other geo-disciplines (hydrogeology, hydro-geochemistry, rock mechanics, thermal properties and transport properties) will be developed. Great care is taken to arrive at a general consistency in the description of the various models and assessment of uncertainty and possible needs of alternative models.Here, a numerical model is developed on a regional-scale (hundreds of square kilometres) to understand the zone of influence for groundwater flow that effects the Simpevarp area. Transport calculations are then performed by particle tracking from a local-scale release area (tens of square kilometres) to identify potential discharge areas for the site. The transport from the two site-scale release areas (a few square kilometres) at the Simpevarp site and the Laxemar site are also considered more specifically and using greater grid resolution.The main

Hydrogeology of the Ramapo River-Woodbury Creek valley-fill aquifer system and adjacent areas in eastern Orange County, New York

Science.gov (United States)

Heisig, Paul M.

2015-01-01

The hydrogeology of the valley-fill aquifer system and surrounding watershed areas was investigated within a 23-mile long, fault-controlled valley in eastern Orange County, New York. Glacial deposits form a divide within the valley that is drained to the north by Woodbury Creek and is drained to the south by the Ramapo River. Surficial geology, extent and saturated thickness of sand and gravel aquifers, extent of confining units, bedrock-surface elevation beneath valleys, major lineaments, and the locations of wells for which records are available were delineated on an interactive map.

Hydrogeological modelling for migration of radioactivity

International Nuclear Information System (INIS)

Sunny, Faby; Chopra, Manish; Oza, R.B.

2016-01-01

The hydrogeological modelling for migration of radionuclides basically involves modelling of groundwater flow and contaminant transport through the groundwater. The water that occurs below the land surface or within the lithosphere is called groundwater. The groundwater constitutes about 4 % of the total water on the earth and about 30 % of freshwater on the earth. Groundwater models describe groundwater flow and contaminant transport processes using mathematical equations that are based on certain simplifying assumptions. These assumptions typically involve the direction of flow, geometry of the aquifer, the heterogeneity or anisotropy of sediments or bedrock within the aquifer, the contaminant transport mechanisms and chemical reactions. Because of the simplifying assumptions and the many uncertainties in the values of data, a model must be viewed as an approximation and not an exact duplication of field conditions. However, these models are useful investigation tool for a number of applications such as prediction of the possible fate and migration of contaminants for risk evaluation; tracking the possible pathway of groundwater contamination; evaluation of design of hydraulic containment and pump-and-treat systems; design of groundwater monitoring networks; evaluation of regional groundwater resources and prediction of the effect of future groundwater withdrawals on groundwater levels

Final disposal of spent nuclear fuel in Finnish bedrock - Kivetty site report

International Nuclear Information System (INIS)

Anttila, P.; Ahokas, H.; Front, K.

1999-06-01

the Total Dissolved Solids (TDS) and chloride contents increase with depth. The chemically most evolved groundwaters are found in borehole KR1 with a TDS value of 233 mg/l and a chloride content of 48 mg/l in KR5. Reducing conditions are expected to exist at depth, which are favourable in terms of low radionuclide solubility and slow canister corrosion. Potentially suitable bedrock blocks have been identified at the site for locating a repository for spent fuel in the depth range of 400 - 700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones should be avoided when locating the deposition tunnels and disposal holes. (orig.)

Characterising Bedrock Aquifer Systems in Korea Using Paired Water-Level Monitoring Data

Directory of Open Access Journals (Sweden)

Jae Min Lee

2017-06-01

Full Text Available This study focused on characterising aquifer systems based on water-level changes observed systematically at 159 paired groundwater monitoring wells throughout Korea. Using spectral analysis, principal component analysis (PCA, and cross-correlation analysis with linear regression, aquifer conditions were identified from the comparison of water-level changes in shallow alluvial and deep bedrock monitoring wells. The spectral analysis could identify the aquifer conditions (i.e., unconfined, semi-confined and confined of 58.5% of bedrock wells and 42.8% of alluvial wells: 93 and 68 wells out of 159 wells, respectively. Even among the bedrock wells, 50 wells (53.7% exhibited characteristics of the unconfined condition, implying significant vulnerability of the aquifer to contaminants from the land surface and shallow depths. It appears to be better approach for deep bedrock aquifers than shallow alluvial aquifers. However, significant portions of the water-level changes remained unclear for categorising aquifer conditions due to disturbances in data continuity. For different aquifer conditions, PCA could show typical pattern and factor scores of principal components. Principal component 1 due to wet-and-dry seasonal changes and water-level response time was dominant covering about 55% of total variances of each aquifer conditions, implying the usefulness of supplementary method of aquifer characterisation. Cross-correlation and time-lag analysis in the water-level responses to precipitations clearly show how the water levels in shallow and deep wells correspond in time scale. No significant differences in time-lags was found between shallow and deep wells. However, clear time-lags were found to be increasing from unconfined to confined conditions: from 1.47 to 2.75 days and from 1.78 to 2.75 days for both shallow alluvial and deep bedrock wells, respectively. In combination of various statistical methods, three types of water-level fluctuation

Movements and instability in the Swedish bedrock

International Nuclear Information System (INIS)

Moerner, N.A.

1977-01-01

The report gives a geological evaluation of the Swedish bedrock and its movements during the last 20,000 years, which may serve as a base for further evaluations of the possibilities of storing nuclear waste in the bedrock. The Swedish bedrock is by no means stable. Like all other bedrocks it is unstable. The Swedish bedrock has an old and rich tectono-geodynamic inheritance. Irregularities in the uplift in the form of shoreline bends and isobase irregularities have been established with ancient shorelines and geodetic data. They are in general all related to major faultlines and bedrock seams. Bouldery end moraines and bouldery ground in general register paleopseismic activity -(these areas must hence be excluded as alternatives for storage of nuclear waste in the bedrock). The next ice age, is either on its way or it will, under the most favorable circumstances, have begun 20,000years from now (AP). At the next ice age, all the seismic and neotectonic effects from the deglaciation period will be repeated. During an ice age. Nuclear waste cannot bestored in the bedrock. If one succed in finding a Precambrain bedrock unit within an area of smooth uplift, absence of recent earthquakes, the bedrock surface of which shows few fractures and no faultlines, and where the surroundings exhibit normal moraine features and normal till composition, this area must still be evaluated with respect to that which will happen and may happen in connection with the next ice age and in connection with the cyclic gravitational changes in the present linear uplift. (author)

Investigation of BWR stability in Forsmark 2

International Nuclear Information System (INIS)

Oguma, R.; Reisch, F.; Bergdahl, B.G.; Lorenzen, J.; Aakerhielm, F.; Kellner, S.

1988-01-01

A series of noise measurements have been conducted at the Forsmark-2 reactor during its start-up operation after the revision in 1987. The main purpose was to investigate the BWR stability problem based on noise analysis, i.e. the problem of resonant power oscillation with frequency of about 0.5 Hz, which tends to arise at high power and low core flow condition. The noise analysis was performed to estimate the noise source which gives rise to the power oscillation, to evaluate the stability condition of the Forsmark-2 reactor in terms of the decay ratio (DR), as well as to investigate a safety related problem in connection with the BWR stability. The results indicate that the power oscillation is due to dynamic coupling between the neutron kinetics and thermal-hydraulics via void reactivity feedback. The DR reached as high as ≅ 0.7 at 63% of the rated power and 4100 kg/s of the total core flow. An investigation was made for the noise recording which represents a strong pressure oscillation with a peak frequency at 0.33 Hz. The result suggests that such pressure oscillation, if the peak frequency coincided with that of the resonant power oscillation, might become a cause of scram. The present noise analysis indicates the importance of a BWR on-line surveillance system with functions like stability condition monitoring and control system diagnosis. (orig.)

Validation of coastal oceanographic models at Forsmark. Site descriptive modelling SDM-Site Forsmark

Energy Technology Data Exchange (ETDEWEB)

Engqvist, Anders (A och I Engqvist Konsult HB, Vaxholm (SE)); Andrejev, Oleg (Finnish Inst. of Marine Research, Helsinki (FI))

2008-01-15

The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterisation at two different locations, the Forsmark and the Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The characterisation work is divided into an initial site investigation phase and a complete site investigation phase. In this context, the water exchange of the coastal zone is one link of the chain of possible nuclide transport mechanisms that must be assessed in the site description of potential repository areas. For the purpose of validating the pair of nested 3D-models employed to simulate the water exchange in the near-shore coastal zone in the Forsmark area, an encompassing measurement program entailing six stations has been performed. The design of this program was to first assess to what degree the forcing of the fine resolution (FR) model of the Forsmark study area at its interfacial boundary to the coarse resolution (CR) model of the entire Baltic was reproduced. In addition to this scrutiny it is of particular interest how the time-varying density-determining properties, salinity and temperature, at the borders are propagated into the FR-domain, since this corresponds to the most efficient mode of water exchange. An important part of the validation process has been to carefully evaluate which measurement data that can be considered reliable. The result was that several periods of foremost near-surface salinity data had to be discarded due to growth of algae on the conductivity sensors. Lack of thorough absolute calibration of the salinity meters also necessitates dismissal of measurement data. Relative the assessed data that can be accepted as adequate, the outcome of the validation can be summarized in five points: (i) The surface-most salinity of the CR-model drifts downward a little less than one practical salinity unit (psu) per year, requiring that the ensuing correlation analysis be subdivided into periods of a

Forsmark site investigation. Reflection seismic studies in the Forsmark area, 2004: Stage 2

Energy Technology Data Exchange (ETDEWEB)

Juhlin, Christopher; Palm, Hans [Uppsala Univ. (Sweden). Dept. of Earth Sciences

2005-06-15

Reflection seismic data were acquired in the Fall of 2004 in the Forsmark area, located about 140 km north of Stockholm, Sweden. The Forsmark area has been targeted by SKB as a possible storage site for spent nuclear fuel. About 25 km of high resolution (nominal source and receiver spacing of maximum 10 m and a minimum of 160 active channels) seismic data were acquired along 10 profiles, varying in length from about 1 km to over 4 km. Three of these profiles are extensions of profiles that were acquired in 2002 (Stage 1). While the 2002 Stage 1 profiles were geared towards acquiring data from within the relatively undeformed lens, the current study focused on acquiring data from the boundaries of the lens. Data acquisition was also concentrated towards the western part of the candidate area. Data were acquired using a combination of the same explosive source as in Stage 1 (1575 g of explosives) and the VIBSIST mechanical source consisting of an industrial hammer mounted on a tractor. Earlier tests in Laxemar had shown that the VIBSIST source gives comparable data to the explosive source and is less expensive. It can also be used in areas where explosives are prohibited, such as close to the nuclear power plant. At present, the source cannot be used in the terrain, therefore an explosive component is still required. About 80% of the 2100 source points were activated using the VIBSIST system. Stacked sections from the new profiles are generally consistent with the Stage 1 results. Reflections from the prominent south dipping A1 reflector can be observed on most profiles, however, it is not clear if it can be traced all the way to the surface. Neither is it clearly observed below the power plant, suggesting its lateral extent is limited to the west. Instead, a gently east dipping reflector (B8) is interpreted below the power plant. Reflections consistent with the A2 reflector are also found on two profiles, but cannot be traced very far to the south, suggesting that

Validation of coastal oceanographic models at Forsmark. Site descriptive modelling SDM-Site Forsmark

International Nuclear Information System (INIS)

Engqvist, Anders; Andrejev, Oleg

2008-01-01

The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterisation at two different locations, the Forsmark and the Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The characterisation work is divided into an initial site investigation phase and a complete site investigation phase. In this context, the water exchange of the coastal zone is one link of the chain of possible nuclide transport mechanisms that must be assessed in the site description of potential repository areas. For the purpose of validating the pair of nested 3D-models employed to simulate the water exchange in the near-shore coastal zone in the Forsmark area, an encompassing measurement program entailing six stations has been performed. The design of this program was to first assess to what degree the forcing of the fine resolution (FR) model of the Forsmark study area at its interfacial boundary to the coarse resolution (CR) model of the entire Baltic was reproduced. In addition to this scrutiny it is of particular interest how the time-varying density-determining properties, salinity and temperature, at the borders are propagated into the FR-domain, since this corresponds to the most efficient mode of water exchange. An important part of the validation process has been to carefully evaluate which measurement data that can be considered reliable. The result was that several periods of foremost near-surface salinity data had to be discarded due to growth of algae on the conductivity sensors. Lack of thorough absolute calibration of the salinity meters also necessitates dismissal of measurement data. Relative the assessed data that can be accepted as adequate, the outcome of the validation can be summarized in five points: (i) The surface-most salinity of the CR-model drifts downward a little less than one practical salinity unit (psu) per year, requiring that the ensuing correlation analysis be subdivided into periods of a

Site investigation SFR. Bedrock geology

International Nuclear Information System (INIS)

Curtis, Philip; Markstroem, Ingemar; Petersson, Jesper; Triumf, Carl-Axel; Isaksson, Hans; Mattsson, Haakan

2011-12-01

SKB is currently carrying out an assessment of the future extension of the final repository for low and middle level radioactive operational waste, SFR. The planned SFR extension lies at a relatively shallow depth (-50 to -200 masl) compared with the planned Forsmark facility for spent nuclear fuel (-400 to -500 masl). The main aim of the multidisciplinary modelling project involving geology, hydrogeology, hydrogeochemistry and rock mechanical modelling is to describe the rock volume for the planned extension of SFR that was presented in /SKB 2008a/. The results of the modelling project in the form of a forthcoming site descriptive model will supply the basis for site-adapted design including engineering characteristics, in addition to a general assessment of the site suitability. The current report presents the results of the geological work with the deterministic rock domain and deformation zone models (version 1.0) and forms a basis for the three other disciplines in the modelling work. The shallow depth of SFR and its proposed extension means that the facility lies partly within the rock volume affected by the effects of stress release processes during loading and unloading cycles, with an associated increased frequency of open sub-horizontal fractures in the near-surface realm (above -150 masl) compared with that observed at greater depths. The main report describes the data input to the modelling work, the applied modelling methodology and the overall results. More detailed descriptions of the individual modelled deformation zones and rock domains are included in the appendices. The geological modelling work during version 1.0 follows SKB's established methodology using the Rock Visualisation System (RVS). The deformation zone model version 1.0 is a further development of the previous version 0.1 /Curtis et al. 2009/. While the main input to deformation zone model version 0.1 was older geological data from the construction of SFR, including drawings of the

Site investigation SFR. Bedrock geology

Energy Technology Data Exchange (ETDEWEB)

Curtis, Philip; Markstroem, Ingemar (Golder Associates AB (Sweden)); Petersson, Jesper (Vattenfall Power Consultant AB (Sweden)); Triumf, Carl-Axel; Isaksson, Hans; Mattsson, Haakan (GeoVista AB (Sweden))

2011-12-15

SKB is currently carrying out an assessment of the future extension of the final repository for low and middle level radioactive operational waste, SFR. The planned SFR extension lies at a relatively shallow depth (-50 to -200 masl) compared with the planned Forsmark facility for spent nuclear fuel (-400 to -500 masl). The main aim of the multidisciplinary modelling project involving geology, hydrogeology, hydrogeochemistry and rock mechanical modelling is to describe the rock volume for the planned extension of SFR that was presented in /SKB 2008a/. The results of the modelling project in the form of a forthcoming site descriptive model will supply the basis for site-adapted design including engineering characteristics, in addition to a general assessment of the site suitability. The current report presents the results of the geological work with the deterministic rock domain and deformation zone models (version 1.0) and forms a basis for the three other disciplines in the modelling work. The shallow depth of SFR and its proposed extension means that the facility lies partly within the rock volume affected by the effects of stress release processes during loading and unloading cycles, with an associated increased frequency of open sub-horizontal fractures in the near-surface realm (above -150 masl) compared with that observed at greater depths. The main report describes the data input to the modelling work, the applied modelling methodology and the overall results. More detailed descriptions of the individual modelled deformation zones and rock domains are included in the appendices. The geological modelling work during version 1.0 follows SKB's established methodology using the Rock Visualisation System (RVS). The deformation zone model version 1.0 is a further development of the previous version 0.1 /Curtis et al. 2009/. While the main input to deformation zone model version 0.1 was older geological data from the construction of SFR, including drawings of

Three-dimensional hydrogeologic framework model of the Rio Grande transboundary region of New Mexico and Texas, USA, and northern Chihuahua, Mexico

Science.gov (United States)

Sweetkind, Donald S.

2017-09-08

As part of a U.S. Geological Survey study in cooperation with the Bureau of Reclamation, a digital three-dimensional hydrogeologic framework model was constructed for the Rio Grande transboundary region of New Mexico and Texas, USA, and northern Chihuahua, Mexico. This model was constructed to define the aquifer system geometry and subsurface lithologic characteristics and distribution for use in a regional numerical hydrologic model. The model includes five hydrostratigraphic units: river channel alluvium, three informal subdivisions of Santa Fe Group basin fill, and an undivided pre-Santa Fe Group bedrock unit. Model input data were compiled from published cross sections, well data, structure contour maps, selected geophysical data, and contiguous compilations of surficial geology and structural features in the study area. These data were used to construct faulted surfaces that represent the upper and lower subsurface hydrostratigraphic unit boundaries. The digital three-dimensional hydrogeologic framework model is constructed through combining faults, the elevation of the tops of each hydrostratigraphic unit, and boundary lines depicting the subsurface extent of each hydrostratigraphic unit. The framework also compiles a digital representation of the distribution of sedimentary facies within each hydrostratigraphic unit. The digital three-dimensional hydrogeologic model reproduces with reasonable accuracy the previously published subsurface hydrogeologic conceptualization of the aquifer system and represents the large-scale geometry of the subsurface aquifers. The model is at a scale and resolution appropriate for use as the foundation for a numerical hydrologic model of the study area.

Site investigation SFR. Vegetation in streams in the Forsmark area

International Nuclear Information System (INIS)

Andersson, Eva; Aquilonius, Karin; Sivars Becker, Lena; Borgiel, Mikael

2011-09-01

The streams in the model area of Forsmark have previously been thoroughly investigated regarding water chemistry, hydrology, bottom substrate, flooding, percentage coverage of macrophytes and fish migration. Retention of radionuclides in a stream ecosystem is assumed to occur by sorption to sediments or by uptake of radionuclides by macrophytes and it is therefore of interest to know the biomass and production of macrophytes in the streams included in a safety assessment. The general aim of this study was to examine the relation between biomass and the percentage cover of vegetation in streams in the Forsmark area. In this study streams within and nearby the candidate area in Forsmark was investigated. The somewhat larger streams Forsmarksaan and Olandsaan nearby the candidate area, are assumed to be more similar to future streams developing in Forsmark due to landrise, than the smaller streams present in the candidate area today. In total 22 vegetation samples were gathered in order to estimate the biomass at the sites. Percentage coverage of macrophytes, and dominating species were noted and the above ground macrophytes were sampled for biomass analysis. In the smaller streams, the biomass varied between 6 and almost 358 g dry weight per square metre. In the larger streams, the dry biomass varied between 0 and 247 g dry weight per square meter. There were no significant difference between macrophyte biomass in smaller and the larger stream. In total 13 macrophyte species were found. The biomass dry weight at 100% covering degree varied depending on macrophyte species. Although this was a rather small study, it is evident that the biomasses do vary a wide range between sampling squares in the area. However, although it may be difficult to use this data set to estimate the biomass in a specific square meter in the stream section, the relation between biomass weight and covering degree is sufficient to be used when fitting biomass to macrophyte coverage for entire

Site investigation SFR. Vegetation in streams in the Forsmark area

Energy Technology Data Exchange (ETDEWEB)

Andersson, Eva (Svensk Nuclear Fuel and Waste Management Co. (Sweden)); Aquilonius, Karin; Sivars Becker, Lena (Studsvik Nuclear AB (Sweden)); Borgiel, Mikael (Sveriges Vattenekologer AB (Sweden))

2011-09-15

The streams in the model area of Forsmark have previously been thoroughly investigated regarding water chemistry, hydrology, bottom substrate, flooding, percentage coverage of macrophytes and fish migration. Retention of radionuclides in a stream ecosystem is assumed to occur by sorption to sediments or by uptake of radionuclides by macrophytes and it is therefore of interest to know the biomass and production of macrophytes in the streams included in a safety assessment. The general aim of this study was to examine the relation between biomass and the percentage cover of vegetation in streams in the Forsmark area. In this study streams within and nearby the candidate area in Forsmark was investigated. The somewhat larger streams Forsmarksaan and Olandsaan nearby the candidate area, are assumed to be more similar to future streams developing in Forsmark due to landrise, than the smaller streams present in the candidate area today. In total 22 vegetation samples were gathered in order to estimate the biomass at the sites. Percentage coverage of macrophytes, and dominating species were noted and the above ground macrophytes were sampled for biomass analysis. In the smaller streams, the biomass varied between 6 and almost 358 g dry weight per square metre. In the larger streams, the dry biomass varied between 0 and 247 g dry weight per square meter. There were no significant difference between macrophyte biomass in smaller and the larger stream. In total 13 macrophyte species were found. The biomass dry weight at 100% covering degree varied depending on macrophyte species. Although this was a rather small study, it is evident that the biomasses do vary a wide range between sampling squares in the area. However, although it may be difficult to use this data set to estimate the biomass in a specific square meter in the stream section, the relation between biomass weight and covering degree is sufficient to be used when fitting biomass to macrophyte coverage for entire

The limnic ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM-Site

Energy Technology Data Exchange (ETDEWEB)

Norden, Sara; Soederbaeck, Bjoern [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Andersson, Eva [SWECO, Stockholm (Sweden)

2008-11-15

The overall objective of this report is to provide a thorough description of the limnic ecosystems at both Forsmark and Laxemar-Simpevarp. This information may be used in the Safety Assessment and as a basis for the Environmental Impact Assessment. Three aims were set up for the report: 1) to characterize and describe the limnic ecosystems today and in the past in the Forsmark and Laxemar-Simpevarp areas and compare these ecosystems with limnic ecosystems in other areas; 2) to evaluate and visualize major pools, fluxes and sinks of elements within the limnic ecosystems; and finally 3) to describe human impact on the limnic ecosystems. The report includes a thorough description of the lakes and streams in Forsmark and Laxemar-Simpevarp and covers the following areas: catchment area characteristics, hydrology, climate, sediment characteristics, physical characteristics of streams, habitat distribution in lakes, biotic components, water chemistry, comparisons with other lakes and streams in the region, and a historical description. Ecosystem models for carbon and mass balances for a number of elements have been calculated to further improve the understanding of the lake ecosystems. Important processes for the safety assessment are described and evaluated in the report. The Forsmark regional model area contains more than 20 permanent lakes and pools. All lakes are small and shallow, and are characterized as oligotrophic hardwater lakes. Calcareous soils in the area give rise to high calcium concentrations in the surface water, which in turn leads to high pH and low nutrient concentrations in water as phosphorus often co-precipitates with calcium. The shallow depths and moderate water colour permit photosynthesis in the entire benthic habitat of the lakes, and the bottoms are covered by dense stands of the macroalgae Chara sp. Moreover, many of the lakes also have a thick microbial mat (>10 cm), consisting of cyanobacteria and diatoms, in the benthic habitat. Fish in

Undergraduate Education in Hydrogeology.

Science.gov (United States)

Tinker, John Richard, Jr.

1989-01-01

Discusses a course at the University of Wisconsin-Eau Claire which improved instruction in physical hydrogeology, chemical hydrogeology, and water resources. Describes 14 laboratory activities including objectives, methods, and a list of equipment needed. (Author/MVL)

Integrated Characterization of DNAPL Source Zone Architecture in Clay Till and Limestone Bedrock

DEFF Research Database (Denmark)

Broholm, Mette Martina; Janniche, Gry Sander; Fjordbøge, Annika Sidelmann

2014-01-01

Background/Objectives. Characterization of dense non-aqueous phase liquid (DNAPL) source zone architecture is essential to develop accurate site specific conceptual models, delineate and quantify contaminant mass, perform risk assessment, and select and design remediation alternatives. The activi......Background/Objectives. Characterization of dense non-aqueous phase liquid (DNAPL) source zone architecture is essential to develop accurate site specific conceptual models, delineate and quantify contaminant mass, perform risk assessment, and select and design remediation alternatives...... innovative investigation methods and characterize the source zone hydrogeology and contamination to obtain an improved conceptual understanding of DNAPL source zone architecture in clay till and bryozoan limestone bedrock. Approach/Activities. A wide range of innovative and current site investigative tools...... for direct and indirect documentation and/or evaluation of DNAPL presence were combined in a multiple lines of evidence approach. Results/Lessons Learned. Though no single technique was sufficient for characterization of DNAPL source zone architecture, the combined use of membrane interphase probing (MIP...

HydroCube: an entity-relationship hydrogeological data model

Science.gov (United States)

Wojda, Piotr; Brouyère, Serge; Derouane, Johan; Dassargues, Alain

2010-12-01

Managing, handling and accessing hydrogeological information depends heavily on the applied hydrogeological data models, which differ between institutions and countries. The effective dissemination of hydrogeological information requires the convergence of such models to make hydrogeological information accessible to multiple users such as universities, water suppliers, and administration and research organisations. Furthermore, because hydrogeological studies are complex, they require a wide variety of high-quality hydrogeological data with appropriate metadata in clearly designed and coherent structures. A need exists, therefore, to develop and implement hydrogeological data models that cover, as much as possible, the full hydrogeological domain. A new data model, called HydroCube, was developed for the Walloon Region in Belgium in 2005. The HydroCube model presents an innovative holistic project-based approach which covers a full set of hydrogeological concepts and features, allowing for effective hydrogeological project management. The model stores data relating to the project locality, hydrogeological equipment, and related observations and measurements. In particular, it focuses on specialized hydrogeological field experiments such as pumping and tracer tests. This logical data model uses entity-relationship diagrams and it has been implemented in the Microsoft Access environment. It has been enriched with a fully functional user interface.

Statistical geological discrete fracture network model. Forsmark modelling stage 2.2

Energy Technology Data Exchange (ETDEWEB)

Fox, Aaron; La Pointe, Paul [Golder Associates Inc (United States); Simeonov, Assen [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Hermanson, Jan; Oehman, Johan [Golder Associates AB, Stockholm (Sweden)

2007-11-15

The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site characterization at two different locations, Forsmark and Laxemar, in order to locate a site for a final geologic repository for spent nuclear fuel. The program is built upon the development of Site Descriptive Models (SDMs) at specific timed data freezes. Each SDM is formed from discipline-specific reports from across the scientific spectrum. This report describes the methods, analyses, and conclusions of the geological modeling team with respect to a geological and statistical model of fractures and minor deformation zones (henceforth referred to as the geological DFN), version 2.2, at the Forsmark site. The geological DFN builds upon the work of other geological modelers, including the deformation zone (DZ), rock domain (RD), and fracture domain (FD) models. The geological DFN is a statistical model for stochastically simulating rock fractures and minor deformation zones as a scale of less than 1,000 m (the lower cut-off of the DZ models). The geological DFN is valid within four specific fracture domains inside the local model region, and encompassing the candidate volume at Forsmark: FFM01, FFM02, FFM03, and FFM06. The models are build using data from detailed surface outcrop maps and the cored borehole record at Forsmark. The conceptual model for the Forsmark 2.2 geological revolves around the concept of orientation sets; for each fracture domain, other model parameters such as size and intensity are tied to the orientation sets. Two classes of orientation sets were described; Global sets, which are encountered everywhere in the model region, and Local sets, which represent highly localized stress environments. Orientation sets were described in terms of their general cardinal direction (NE, NW, etc). Two alternatives are presented for fracture size modeling: - the tectonic continuum approach (TCM, TCMF) described by coupled size-intensity scaling following power law distributions

Statistical geological discrete fracture network model. Forsmark modelling stage 2.2

International Nuclear Information System (INIS)

Fox, Aaron; La Pointe, Paul; Simeonov, Assen; Hermanson, Jan; Oehman, Johan

2007-11-01

The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site characterization at two different locations, Forsmark and Laxemar, in order to locate a site for a final geologic repository for spent nuclear fuel. The program is built upon the development of Site Descriptive Models (SDMs) at specific timed data freezes. Each SDM is formed from discipline-specific reports from across the scientific spectrum. This report describes the methods, analyses, and conclusions of the geological modeling team with respect to a geological and statistical model of fractures and minor deformation zones (henceforth referred to as the geological DFN), version 2.2, at the Forsmark site. The geological DFN builds upon the work of other geological modelers, including the deformation zone (DZ), rock domain (RD), and fracture domain (FD) models. The geological DFN is a statistical model for stochastically simulating rock fractures and minor deformation zones as a scale of less than 1,000 m (the lower cut-off of the DZ models). The geological DFN is valid within four specific fracture domains inside the local model region, and encompassing the candidate volume at Forsmark: FFM01, FFM02, FFM03, and FFM06. The models are build using data from detailed surface outcrop maps and the cored borehole record at Forsmark. The conceptual model for the Forsmark 2.2 geological revolves around the concept of orientation sets; for each fracture domain, other model parameters such as size and intensity are tied to the orientation sets. Two classes of orientation sets were described; Global sets, which are encountered everywhere in the model region, and Local sets, which represent highly localized stress environments. Orientation sets were described in terms of their general cardinal direction (NE, NW, etc). Two alternatives are presented for fracture size modeling: - the tectonic continuum approach (TCM, TCMF) described by coupled size-intensity scaling following power law distributions

Landscape Forsmark - data, methodology and results for SR-Site

Energy Technology Data Exchange (ETDEWEB)

Lindborg, Tobias [ed.; Svensk Kaernbraenslehantering AB (Sweden)

2010-12-15

This report presents an integrated description of the landscape at the Forsmark site during the succession from present conditions to the far future. It was produced as a part of the biosphere modelling within the SR-Site safety assessment. The report gives a description of input data, methodology and resulting models used to support the current understanding of the landscape used in SR-Site. It is intended to describe the properties and conditions at the site and to give information essential for demonstrating understanding. The report relies heavily on a number of discipline-specific background reports concerning details of the data analyses and modelling. Long-term landscape development in the Forsmark area is dependent on two main and partly interdependent factors, i.e. climate variations and shoreline displacement. These two factors in combination strongly affect a number of processes, which in turn determine the development of ecosystems. Some examples of such processes are erosion and sedimentation, groundwater recharge and discharge, soil formation, primary production and decomposition of organic matter. The biosphere at the site during the next 1,000 years is assumed to be quite similar to the present situation. The most important changes are the natural infilling of lakes and a slight withdrawal of the sea with its effects on the near-shore areas and the shallow coastal basins. The climate during the rest of the temperate period may vary considerably, with both warmer and colder periods. The main effect of temperature changes will be on the vegetation period. Changed temperatures may give rise to drier or wetter climate and to changed snow cover and frost characteristics, and this can in turn affect the dominant vegetation and mire build-up. The description of the Forsmark ecosystem succession during a glacial cycle is one of the main features of the SR-Site biosphere modelling. The future areas potentially affected by deep groundwater discharge are

Landscape Forsmark - data, methodology and results for SR-Site

International Nuclear Information System (INIS)

Lindborg, Tobias

2010-12-01

This report presents an integrated description of the landscape at the Forsmark site during the succession from present conditions to the far future. It was produced as a part of the biosphere modelling within the SR-Site safety assessment. The report gives a description of input data, methodology and resulting models used to support the current understanding of the landscape used in SR-Site. It is intended to describe the properties and conditions at the site and to give information essential for demonstrating understanding. The report relies heavily on a number of discipline-specific background reports concerning details of the data analyses and modelling. Long-term landscape development in the Forsmark area is dependent on two main and partly interdependent factors, i.e. climate variations and shoreline displacement. These two factors in combination strongly affect a number of processes, which in turn determine the development of ecosystems. Some examples of such processes are erosion and sedimentation, groundwater recharge and discharge, soil formation, primary production and decomposition of organic matter. The biosphere at the site during the next 1,000 years is assumed to be quite similar to the present situation. The most important changes are the natural infilling of lakes and a slight withdrawal of the sea with its effects on the near-shore areas and the shallow coastal basins. The climate during the rest of the temperate period may vary considerably, with both warmer and colder periods. The main effect of temperature changes will be on the vegetation period. Changed temperatures may give rise to drier or wetter climate and to changed snow cover and frost characteristics, and this can in turn affect the dominant vegetation and mire build-up. The description of the Forsmark ecosystem succession during a glacial cycle is one of the main features of the SR-Site biosphere modelling. The future areas potentially affected by deep groundwater discharge are

Final disposal of spent nuclear fuel in Finnish bedrock - Kivetty site report

Energy Technology Data Exchange (ETDEWEB)

Anttila, P. [Fortum Engineering Oy, Vantaa (Finland); Ahokas, H.; Front, K. [Fintact Oy (Finland)] [and others

1999-06-01

Kivetty is classified as fresh water and the Total Dissolved Solids (TDS) and chloride contents increase with depth. The chemically most evolved groundwaters are found in borehole KR1 with a TDS value of 233 mg/l and a chloride content of 48 mg/l in KR5. Reducing conditions are expected to exist at depth, which are favourable in terms of low radionuclide solubility and slow canister corrosion. Potentially suitable bedrock blocks have been identified at the site for locating a repository for spent fuel in the depth range of 400 - 700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones should be avoided when locating the deposition tunnels and disposal holes. (orig.)

Groundwater flow modelling of periods with periglacial and glacial climate conditions - Laxemar

Energy Technology Data Exchange (ETDEWEB)

Vidstrand, Patrik (TerraSolve AB, Floda (Sweden)); Rhen, Ingvar (SWECO Environment AB, Falun (Sweden)); Zugec, Nada (Bergab, Goeteborg (Sweden))

2010-12-15

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report is concerned with the modelling of a repository at the Laxemar-Simpevarp site during periglacial and glacial climate conditions as a comparison to corresponding modelling carried out for Forsmark /Vidstrand et al. 2010/. The groundwater flow modelling study reported here comprises a coupled thermal-hydraulic-chemical (T-H-C) analysis of periods with periglacial and glacial climate conditions. The objective of the report is to provide bounding hydrogeological estimates at different stages during glaciation and deglaciation of a glacial cycle at Laxemar. Three cases with different climate conditions are analysed here: (i) Temperate case, (ii) Glacial case without permafrost, and (iii) Glacial case with permafrost. The glacial periods are transient and encompass approximately 13,000 years. The simulation results comprise pressures, Darcy fluxes, and water salinities, as well as advective transport performance measures obtained by particle tracking such as flow path lengths, travel times and flow-related transport resistances. The modelling is accompanied by a sensitivity study that addresses the impact of the following matters: the direction of the ice sheet advance and the bedrock hydraulic and transport properties

Use of stratigraphic, petrographic, hydrogeologic and geochemical information for hydrogeologic modelling based on geostatistical simulation

International Nuclear Information System (INIS)

Rohlig, K.J.; Fischer, H.; Poltl, B.

2004-01-01

This paper describes the stepwise utilization of geologic information from various sources for the construction of hydrogeological models of a sedimentary site by means of geostatistical simulation. It presents a practical application of aquifer characterisation by firstly simulating hydrogeological units and then the hydrogeological parameters. Due to the availability of a large amount of hydrogeological, geophysical and other data and information, the Gorleben site (Northern Germany) has been used for a case study in order to demonstrate the approach. The study, which has not yet been completed, tries to incorporate as much as possible of the available information and to characterise the remaining uncertainties. (author)

Groundwater in crystalline bedrock

International Nuclear Information System (INIS)

Palmqvist, K.

1990-06-01

The aim of this project was to make detailed descriptions of the geological conditions and the different kinds of leakage in some tunnels in Sweden, to be able to describe the presence of ground water in crystalline bedrock. The studies were carried out in TBM tunnels as well as in conventionally drilled and blasted tunnels. Thanks to this, it has been possible to compare the pattern and appearance of ground water leakage in TBM tunnels and in blasted tunnels. On the basis of some experiments in a TBM tunnel, it has been confirmed that a detailed mapping of leakage gives a good picture of the flow paths and their aquiferous qualities in the bedrock. The same picture is found to apply even in cautious blasted tunnels. It is shown that the ground water flow paths in crystalline bedrock are usually restricted to small channels along only small parts of the fractures. This is also true for fracture zones. It has also been found that the number of flow paths generally increases with the degree of tectonisation, up to a given point. With further tectonisation the bedrock is more or less crushed which, along with mineral alteration, leaves only a little space left for the formation of water channels. The largest individual flow paths are usually found in fracture zones. The total amount of ground water leakage per m tunnel is also greater in fracture zones than in the bedrock between the fracture zones. In mapping visible leakage, five classes have been distinguished according to size. Where possible, the individual leak inflow has been measured during the mapping process. The quantification of the leakage classes made in different tunnels are compared, and some quantification standards suggested. A comparison of leakage in different rock types, tectonic zones, fractures etc is also presented. (author)

Experience from the MTO program at the Forsmark nuclear power plant

International Nuclear Information System (INIS)

Rollenhagen, C.; Andersson, O.

1996-01-01

Within the nuclear industry there are two events which have had a significant impact on the way of thinking and attitudes to safety, although in different ways. The TMI accident at Harrisburg, USA put the focus on the man-machine interface, the way of working and attitudes to safety. The accident at Chernobyl focused on safety management and safety culture. After the Chernobyl accident, safety culture (IAEA INSAG-4) became a commonly used concept which included an overall perspective on safety and an understanding of the interaction between man, technology and organizational matters (MTO). As a result of this understanding, the MTO concept was introduced at the Forsmark nuclear power plant already in 1988 and is today a conceptual way of thinking which is well integrated in the line organization. One of the purposes of this paper is to present some of the work that has been done at Forsmark nuclear power plant under the heading of MTO, both in the past and more recently. (author) 4 figs., 2 tabs

Editors' message--Hydrogeology Journal in 2003

Science.gov (United States)

Voss, Clifford; Olcott, Perry; Schneider, Robert

2004-01-01

Hydrogeology Journal appeared in six issues containing a total of 710 pages and 48 major articles, including 31 Papers and 14 Reports, as well as some Technical Notes and Book Reviews. The number of submitted manuscripts continues to increase. The final issue of 2003 also contained the annual volume index. Hydrogeology Journal (HJ) is an international forum for hydrogeology and related disciplines and authors in 2003 were from about 28 countries. Articles advanced hydrogeologic science and described hydrogeologic systems in many regions worldwide. These articles focused on a variety of general topics and on studies of hydrogeology in 24 countries: Afghanistan, Algeria, Argentina, Australia, Bangladesh, Belgium, Canada, Chile, China, Denmark, France, India, Italy, Mexico, Netherlands, New Zealand, Nigeria, Norway, Portugal, Russia, South Africa, Switzerland, Turkey, and U.S.A. The Guest Editor of the 2003 HJ theme issue on “Hydromechanics in Geology and Geotechnics”, Ove Stephansson, assembled a valuable collection of technical reviews and research papers from eminent authors on important aspects of the subject area.

Hydrogeologic framework and groundwater/surface-water interactions of the upper Yakima River Basin, Kittitas County, central Washington

Science.gov (United States)

Gendaszek, Andrew S.; Ely, D. Matthew; Hinkle, Stephen R.; Kahle, Sue C.; Welch, Wendy B.

2014-01-01

The hydrogeology, hydrology, and geochemistry of groundwater and surface water in the upper (western) 860 square miles of the Yakima River Basin in Kittitas County, Washington, were studied to evaluate the groundwater-flow system, occurrence and availability of groundwater, and the extent of groundwater/surface-water interactions. The study area ranged in altitude from 7,960 feet in its headwaters in the Cascade Range to 1,730 feet at the confluence of the Yakima River with Swauk Creek. A west-to-east precipitation gradient exists in the basin with the western, high-altitude headwaters of the basin receiving more than 100 inches of precipitation per year and the eastern, low-altitude part of the basin receiving about 20 inches of precipitation per year. From the early 20th century onward, reservoirs in the upper part of the basin (for example, Keechelus, Kachess, and Cle Elum Lakes) have been managed to store snowmelt for irrigation in the greater Yakima River Basin. Canals transport water from these reservoirs for irrigation in the study area; additional water use is met through groundwater withdrawals from wells and surface-water withdrawals from streams and rivers. Estimated groundwater use for domestic, commercial, and irrigation purposes is reported for the study area. A complex assemblage of sedimentary, metamorphic, and igneous bedrock underlies the study area. In a structural basin in the southeastern part of the study area, the bedrock is overlain by unconsolidated sediments of glacial and alluvial origin. Rocks and sediments were grouped into six hydrogeologic units based on their lithologic and hydraulic characteristics. A map of their extent was developed from previous geologic mapping and lithostratigraphic information from drillers’ logs. Water flows through interstitial space in unconsolidated sediments, but largely flows through fractures and other sources of secondary porosity in bedrock. Generalized groundwater-flow directions within the

Bedrock Geologic Map of Woodstock, Vermont

Data.gov (United States)

Vermont Center for Geographic Information — Digital Data from VG06-4 Thompson, P. J., 2006, Bedrock Geologic Map of Woodstock, Vermont: VGS Open-File Report VG06-4, scale 1:24,000. The bedrock geologic map...

Groundwater flow modeling of periods with temperate climate conditions for use in a safety assessment of a repository for spent nuclear fuel - 59154

International Nuclear Information System (INIS)

Joyce, Steven; Hartley, Lee; Simpson, Trevor

2012-01-01

Document available in abstract form only. Full text of publication follows: As a part of the license application for a final repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management Company (SKB) has prepared a safety report (SR-Site) that assesses the long-term radiological safety after closure of a repository located at 500 m depth in the Forsmark area, c. 120 km north of Stockholm. The movement and composition of groundwater affect both the key pathways for radionuclide migration and the performance of engineered barriers, and hence are important issues that have to be considered and modelled as part of quantitative assessment calculations. This presentation describes the groundwater flow modelling studies that have been performed to represent the post-closure hydrogeological and hydrochemical situations during temperate climate conditions, and how these are used to support safety assessment calculations and arguments. The collation and implementation of onsite hydrogeological and hydrogeochemical data from the surface based site investigations at Forsmark are used as the basis for defining a reference case for the natural hydrogeological situation at the site (hydrogeological base case). Areas of uncertainty within the current site understanding and the engineered system are examined by a series of flow model variants

Modelling of temperature in deep boreholes and evaluation of geothermal heat flow at Forsmark and Laxemar

Energy Technology Data Exchange (ETDEWEB)

Sundberg, Jan; Back, Paer-Erik; Laendell, Maerta; Sundberg, Anders (GEO INNOVA AB, Linkoeping (Sweden))

2009-06-15

This report presents modelling of temperature and temperature gradients in boreholes in Laxemar and Forsmark and fitting to measured temperature data. The modelling is performed with an analytical expression including thermal conductivity, thermal diffusivity, heat flow, internal heat generation and climate events in the past. As a result of the fitting procedure it is also possible to evaluate local heat flow values for the two sites. However, since there is no independent evaluation of the heat flow, uncertainties in for example thermal conductivity, diffusivity and the palaeoclimate temperature curve are transferred into uncertainties in the heat flow. Both for Forsmark and Laxemar, reasonably good fits were achieved between models and data on borehole temperatures. However, none of the general models achieved a fit within the 95% confidence intervals of the measurements. This was achieved in some cases for the additional optimised models. Several of the model parameters are uncertain. A good model fit does not automatically imply that 'correct' values have been used for these parameters. Similar model fits can be expected with different sets of parameter values. The palaeoclimatically corrected surface mean heat flow at Forsmark and Laxemar is suggested to be 61 and 56 mW/m2 respectively. If all uncertainties are combined, including data uncertainties, the total uncertainty in the heat flow determination is judged to be within +12% to -14% for both sites. The corrections for palaeoclimate are quite large and verify the need of site-specific climate descriptions. Estimations of the current ground surface temperature have been made by extrapolations from measured temperature logging. The mean extrapolated ground surface temperature in Forsmark and Laxemar is estimated to 6.5 deg and 7.3 deg C respectively. This is approximately 1.7 deg C higher for Forsmark, and 1.6 deg C higher for Laxemar compared to data in the report SKB-TR-06-23. Comparison with

Modelling of temperature in deep boreholes and evaluation of geothermal heat flow at Forsmark and Laxemar

International Nuclear Information System (INIS)

Sundberg, Jan; Back, Paer-Erik; Laendell, Maerta; Sundberg, Anders

2009-05-01

This report presents modelling of temperature and temperature gradients in boreholes in Laxemar and Forsmark and fitting to measured temperature data. The modelling is performed with an analytical expression including thermal conductivity, thermal diffusivity, heat flow, internal heat generation and climate events in the past. As a result of the fitting procedure it is also possible to evaluate local heat flow values for the two sites. However, since there is no independent evaluation of the heat flow, uncertainties in for example thermal conductivity, diffusivity and the palaeoclimate temperature curve are transferred into uncertainties in the heat flow. Both for Forsmark and Laxemar, reasonably good fits were achieved between models and data on borehole temperatures. However, none of the general models achieved a fit within the 95% confidence intervals of the measurements. This was achieved in some cases for the additional optimised models. Several of the model parameters are uncertain. A good model fit does not automatically imply that 'correct' values have been used for these parameters. Similar model fits can be expected with different sets of parameter values. The palaeoclimatically corrected surface mean heat flow at Forsmark and Laxemar is suggested to be 61 and 56 mW/m 2 respectively. If all uncertainties are combined, including data uncertainties, the total uncertainty in the heat flow determination is judged to be within +12% to -14% for both sites. The corrections for palaeoclimate are quite large and verify the need of site-specific climate descriptions. Estimations of the current ground surface temperature have been made by extrapolations from measured temperature logging. The mean extrapolated ground surface temperature in Forsmark and Laxemar is estimated to 6.5 deg and 7.3 deg C respectively. This is approximately 1.7 deg C higher for Forsmark, and 1.6 deg C higher for Laxemar compared to data in the report SKB-TR-06-23. Comparison with air

Hydrogeology of Gypsum formations

Directory of Open Access Journals (Sweden)

Klimchouk A.

1996-01-01

Full Text Available Detailed explanation of hydrogeological characteristics of gypsum aquifers is given in various situations: deep-seated karst-confined conditions, subjacent, entrenched and denuded karst types-semi-confined, phreatic and vadose conditions. The hydrogeological evolution of barren exposed gypsum karst and flow velocities in gypsum karst aquifers is also discussed.

Calculating the spatio-temporal variability of bedrock exposure on seasonal hydrograph timescales as a prerequisite to modeling bedrock river evolution

Science.gov (United States)

Hurst, A. A.; Anderson, R. S.; Tucker, G. E.

2017-12-01

Erosion of bedrock river channels exerts significant control on landscape evolution because it communicates climatic and tectonic signals across a landscape by setting the lower erosional boundaries for hillslopes. Hillslope erosion delivers sediment to the channels, which then either store or transport the sediment. At times of high storage, access to the bedrock floor of the channel is limited, inhibiting bedrock erosion. This affects the timescale of channel response to imposed base-level lowering, which in turn affects hillslope erosion. Because occasional exposure of the bedrock bed is a minimum prerequisite for bedrock erosion, we seek to understand the evolution of sediment cover, or scour history, with sufficient resolution to answer when and where the bed is exposed. The scour history at a site is governed by grain size, bed and channel morphology, sediment concentration in the water, and seasonal flow conditions (hydrograph). The transient nature of bedrock exposure during high-flow events implies that short-term sediment cover dynamics are important for predicting long-term bedrock incision rates. Models of channel profile evolution, or of landscape evolution, generally ignore evolution of sediment cover on the hydrograph timescale. To develop insight into the necessary and sufficient conditions for bedrock exposure followed by reburial, we have developed a 1-D model of the evolution of alluvial cover thickness in a long channel profile in response to a seasonal hydrograph. This model tracks erosion, deposition, and the concentration of sediment in the water column separately, and generates histories of scour and fill over the course of the hydrograph. We compare the model's predictions with net-scour measurements in tributaries of the Grand Canyon and with scour-chain and accelerometer measurements in the Cedar River, Washington. By addressing alluvial scour on short timescales, we acknowledge the processes required to allow bedrock incision and

Formative flow in bedrock canyons

Science.gov (United States)

Venditti, J. G.; Kwoll, E.; Rennie, C. D.; Church, M. A.

2017-12-01

In alluvial channels, it is widely accepted that river channel configuration is set by a formative flow that represents a balance between the magnitude and frequency of flood flows. The formative flow is often considered to be one that is just capable of filling a river channel to the top of its banks. Flows much above this formative flow are thought to cause substantial sediment transport and rearrange the channel morphology to accommodate the larger flow. This idea has recently been extended to semi-alluvial channels where it has been shown that even with bedrock exposed, the flows rarely exceed that required to entrain the local sediment cover. What constitutes a formative flow in a bedrock canyon is not clear. By definition, canyons have rock walls and are typically incised vertically, removing the possibility of the walls being overtopped, as can occur in an alluvial channel at high flows. Canyons are laterally constrained, have deep scour pools and often have width to maximum depth ratios approaching 1, an order of magnitude lower than alluvial channels. In many canyons, there are a sequence of irregularly spaced scour pools. The bed may have intermittent or seasonal sediment cover, but during flood flows the sediment bed is entrained leaving a bare bedrock channel. It has been suggested that canyons cut into weak, well-jointed rock may adjust their morphology to the threshold for block plucking because the rock bed is labile during exceptionally large magnitude flows. However, this hypothesis does not apply to canyons cut into massive crystalline rock where abrasion is the dominant erosion process. Here, we argue that bedrock canyon morphology is adjusted to a characteristic flow structure developed in bedrock canyons. We show that the deeply scoured canyon floor is adjusted to a velocity inversion that is present at low flows, but gets stronger at high flows. The effect is to increase boundary shear stresses along the scour pool that forms in constricted

Forsmark - System 522. Recursive linear regression for the determination of heating rate

International Nuclear Information System (INIS)

Carlsson, B.

1980-01-01

The heating rate for reactor tank and steam tubes is limited. The algorithm of the heating rate has been implemented on the computer and compared with real data from Forsmark-2. The evaluation of data shows a considerable improvement of the determination of derivata which contributes to information during heating events. (G.B.)

Present status and an appreciation of the consequences for recreation and outdoor leisure activities from siting a nuclear waste repository at Forsmark

International Nuclear Information System (INIS)

Ottosson, Pia

2007-07-01

This report describes how the area around Forsmark is used with respect to recreation and outdoor life. It also describes the impact of the final repository on recreation and outdoor life if it is located in Forsmark. The studied area is situated in the parish of Forsmark in the municipality of Oesthammar. Forsmark nuclear power plant and the final repository for radioactive operational waste, SFR, are situated within the area and there are both houses and holiday houses. The area is used for leisure pursuit by inhabitants and employees at FKA and SKB, but also by a number of different associations and by tourists. Statistical data shows that the parish of Forsmark is sparsely populated. The area was previously dominated by one big landowner and the land surrounding the nuclear power plant was inaccessible to the general public during that period. The outdoor life is therefore less widespread here than along other parts of the east coast. The value of the area does not lie in paths and trails, bike tracks and bathing places, but in the unspoiled countryside, the wildlife and the bird life. Recreation such as hunting and fishing is very popular in the area. The construction of a final repository will increase traffic and hence increase noise and motion in the area. This will mainly impact the enjoyment value for the people spending time in the area. No other significant consequences are expected as the final repository will be mainly situated within the existing industrial complex and hence the character of the area should remain unchanged

Geology, Bedrock - BEDROCK_TOPOGRAPHY_MM36_IN: Bedrock Topography Contours, Indiana (Indiana Geological Survey, 1:500,000, Line Shapefile)

Data.gov (United States)

NSGIC State | GIS Inventory — Bedrock topography was converted from the original published map, Indiana Geological Survey Miscellaneous Map 36. The contours define the elevation/topography of the...

Macrofauna on rocky substrates in the Forsmark biotest basin. March 1984 - March 1985

International Nuclear Information System (INIS)

Snoeijs, P.; Mo, K.

1987-09-01

The Forsmark biotest basin, situated on the Swedish east coast, is an artificial offshore brackish lake, through which the cooling water is channelled from the Forsmark nuclear power plant to the Bothnian Sea. The biotest basin is up to 10 0 C warmer than the sea surrounding it, and has no ice cover in winter. There is an artificial, fast current in a large part of the basin. Macrofauna on stones in the hydrolittoral belt was sampled at 11 sites in- and outside the basin every third week during one year. The numbers of individuals per m 2 for each taxon were counted. Diversity indices and dominance-diversity curves were computed for each site on the basis of pooled data for the cold season, and for the rest of the year. In total 66 taxa were distinguished in the species lists, of which 3 are sessile, the rest free-living. (orig./DG)

Water activities in Forsmark (Part II). The final disposal facility for spent fuel: water activities above ground; Vattenverksamhet i Forsmark (del II). Slutfoervarsanlaeggningen foer anvaent kaernbraensle: Vattenverksamheter ovan mark

Energy Technology Data Exchange (ETDEWEB)

Werner, Kent [EmpTec (Sweden); Hamren, Ulrika; Collinder, Per [Ekologigruppen AB (Sweden); Ridderstolpe, Peter [WRS Uppsala AB (Sweden)

2010-09-15

The construction of the repository for spent nuclear fuel in Forsmark is associated with a number of measures above ground that constitute water operations according to Chapter 11 in the Swedish Environmental Code. This report, which is an appendix to the Environmental Impact Assessment, describes these water operations, their effects and consequences, and planned measures

Final disposal of spent nuclear fuel in Finnish bedrock. Haestholmen site report

Energy Technology Data Exchange (ETDEWEB)

Anttila, P. [Fortum Engineering Oy, Vantaa (Finland); Ahokas, H. [Fintact Oy, Helsinki (Finland); Front, K. [VTT Communities and Infrastructure, Espoo (Finland)

1999-06-01

from the Baltic Sea some 4000 years ago. The groundwater varies from modern fresh water at shallow depth to saline water at greater depths, the saline water normally representing a mixture of relic Litorina Sea water and meteoric and glacial meltwater. The maximum Total Dissolved Solids (TDS) in the groundwater is 32 g/l and the chloride content 19 g/1. Reducing conditions are expected to exist at depth, which are favourable for low radionuclide solubility and slow canister corrosion. Suitable bedrock volumes have been identified at the site for locating a repository in the depth range of 400-700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones, mainly those that are sub-horizontal, should be avoided when locating the deposition tunnels and disposal holes. The salinity of the groundwater will probably place limits on the use of certain materials for construction purposes. (orig.) 122 refs.

Final disposal of spent nuclear fuel in Finnish bedrock. Haestholmen site report

International Nuclear Information System (INIS)

Anttila, P.; Ahokas, H.; Front, K.

1999-06-01

4000 years ago. The groundwater varies from modern fresh water at shallow depth to saline water at greater depths, the saline water normally representing a mixture of relic Litorina Sea water and meteoric and glacial meltwater. The maximum Total Dissolved Solids (TDS) in the groundwater is 32 g/l and the chloride content 19 g/1. Reducing conditions are expected to exist at depth, which are favourable for low radionuclide solubility and slow canister corrosion. Suitable bedrock volumes have been identified at the site for locating a repository in the depth range of 400-700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones, mainly those that are sub-horizontal, should be avoided when locating the deposition tunnels and disposal holes. The salinity of the groundwater will probably place limits on the use of certain materials for construction purposes. (orig.)

Hydrogeology of Mors

International Nuclear Information System (INIS)

Joshi, A.V.

1982-01-01

The covering layers protect the salt in the dome. Ground water velocities are small and the chalk exhibits good retention properties for the radionuclides. As ground water velocities below 500 m are small, knowledge of hydrogeology over only a small area over the dome is necessary (1 km horizontal transport takes about 15 mill. years). Additionally if the retention properties of the chalk together with radioactive decay are taken into account, it becomes obvious that the nuclides can travel only a few metres into the chalk, before they have decayed to safe radioactive levels. Therefore it does not appear to be necessary to investigate the hydrogeology beyond a few metres from the disposal area. The hydrogeological investigations that have been carried out, although they cover only a limited area, thus give an excellent and sufficient basis for a safety evaluation for determining the suitability of the Mors salt dome for waste disposal. (EG)

Inventory of mammals at Forsmark and Haallnaes

International Nuclear Information System (INIS)

Truve, Johan

2012-08-01

A selection of terrestrial mammals was surveyed in the SKB site investigation areas near Forsmark and Haallnaes between January and April 2012. The methods that were used include snow tracking along line transects, snow tracking along water, aerial survey and fecal pellet counts. The same species were found in 2012 as in previous surveys performed in 2002, 2003 and 2007. Some species show a large variation in density between years and it is difficult to draw any conclusions about their long term development. Several carnivores, i.e. lynx, fox and otter show a positive growth rate in both areas. The wild boar population is also growing whilst moose density remains fairly stable and roe deer are becoming less numerous

Stochastic hydrogeologic units and hydrogeologic properties development for total-system performance assessments. Yucca Mountain Site Characterization Project

International Nuclear Information System (INIS)

Schenker, A.R.; Guerin, D.C.; Robey, T.H.; Rautman, C.A.; Barnard, R.W.

1995-09-01

A stochastic representation of the lithologic units and associated hydrogeologic parameters of the potential high-level nuclear waste repository are developed for use in performance-assessment calculations, including the Total-System Performance Assessment for Yucca Mountain-SNL Second Iteration (TSPA-1993). A simplified lithologic model has been developed based on the physical characteristics of the welded and nonwelded units at Yucca Mountain. Ten hydrogeologic units are developed from site-specific data (lithologic and geophysical logs and core photographs) obtained from the unsaturated and saturated zones. The three-dimensional geostatistical model of the ten hydrogeologic units is based on indicator-coding techniques and improves on the two-dimensional model developed for TSPA91. The hydrogeologic properties (statistics and probability distribution functions) are developed from the results of laboratory tests and in-situ aquifer tests or are derived through fundamental relationships. Hydrogeologic properties for matrix properties, bulk conductivities, and fractures are developed from existing site specific data. Extensive data are available for matrix porosity, bulk density, and matrix saturated conductivity. For other hydrogeologic properties, the data are minimal or nonexistent. Parameters for the properties are developed as beta probability distribution functions. For the model units without enough data for analysis, parameters are developed as analogs to existing units. A relational, analytic approach coupled with bulk conductivity parameters is used to develop fracture parameters based on the smooth-wall-parallel-plate theory. An analytic method is introduced for scaling small-core matrix properties to the hydrogeologic unit scales

Iowa Bedrock Topography

Data.gov (United States)

Iowa State University GIS Support and Research Facility — The Map of the Elevation of the Bedrock Surface in Iowa was compiled using all available data, principally information from GEOSAM, supplemented with well and boring...

The limnic ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM-Site

International Nuclear Information System (INIS)

Norden, Sara; Soederbaeck, Bjoern; Andersson, Eva

2008-11-01

The overall objective of this report is to provide a thorough description of the limnic ecosystems at both Forsmark and Laxemar-Simpevarp. This information may be used in the Safety Assessment and as a basis for the Environmental Impact Assessment. Three aims were set up for the report: 1) to characterize and describe the limnic ecosystems today and in the past in the Forsmark and Laxemar-Simpevarp areas and compare these ecosystems with limnic ecosystems in other areas; 2) to evaluate and visualize major pools, fluxes and sinks of elements within the limnic ecosystems; and finally 3) to describe human impact on the limnic ecosystems. The report includes a thorough description of the lakes and streams in Forsmark and Laxemar-Simpevarp and covers the following areas: catchment area characteristics, hydrology, climate, sediment characteristics, physical characteristics of streams, habitat distribution in lakes, biotic components, water chemistry, comparisons with other lakes and streams in the region, and a historical description. Ecosystem models for carbon and mass balances for a number of elements have been calculated to further improve the understanding of the lake ecosystems. Important processes for the safety assessment are described and evaluated in the report. The Forsmark regional model area contains more than 20 permanent lakes and pools. All lakes are small and shallow, and are characterized as oligotrophic hardwater lakes. Calcareous soils in the area give rise to high calcium concentrations in the surface water, which in turn leads to high pH and low nutrient concentrations in water as phosphorus often co-precipitates with calcium. The shallow depths and moderate water colour permit photosynthesis in the entire benthic habitat of the lakes, and the bottoms are covered by dense stands of the macroalgae Chara sp. Moreover, many of the lakes also have a thick microbial mat (>10 cm), consisting of cyanobacteria and diatoms, in the benthic habitat. Fish in

Topographic and hydraulic controls over alluviation on a bedrock template

Science.gov (United States)

Milan, David; Heritage, George; Entwistle, Neil; Tooth, Stephen

2017-04-01

Bedrock-alluvial anastomosed channels found in dryland rivers are characterised by an over-wide channel cut into the host rock containing a network of interconnecting bedrock sub-channels separated by bedrock influenced interfluve areas. Whilst the channels remain largely free of sediment the interfluves display varying levels of alluviation ranging from bare rock, sand sheets and silt drapes through to consolidated bedrock core bars, islands and lateral deposits. Examination of the sedimentary units associated with the bedrock anastomosed reaches of the Sabie river in the Kruger National Park, South Africa reveal a repeating sequence of coarse sand / fine gravel grading through to silt representing successive flood related depositional units. Unit development in relation to the bedrock template was investigated using pre-flood aerial imagery of bedrock core bar locations and post flood LiDAR data of bedrock anastomosed sites stripped during the 2000 and 2012 extreme flood events. This revealed a propensity for bar development associated with bedrock hollows disconnected from the principal high-energy sub-channels. 2-D morpho-dynamic modelling was used to further investigate spatial patterns of deposition over the bedrock template. Although topographic lows displayed mid-range velocities during peak flow events, these are likely to be preferential routing areas, with sediments stalling in low energy areas on the falling limb of floods. It is also likely that vegetation development plays a fundamental role in the development of alluviated zones, through increasing strength of alluvial units and capturing new sediments. With these results in mind we present a conceptual model for the development of bedrock-core bars, the fundamental unit in bedrock-alluvial anastomosed channels.

Reactor safety study applied to the Forsmark 3 Power Plant

International Nuclear Information System (INIS)

Ericsson, G.; Tiren, L.I.

1978-01-01

A reactor safety study of the Forsmark 3 BWR power plant has been carried out for the purpose of calculating core melt probabilities using WASH-1400 methods. A sensitivity analysis shows that the calculated core melt probability is changed by approximately a factor of 10 depending on assumptions made with respect to the probability of human error. The importance of the availability of off-site power and the influence of common cause failure is also discussed. (author)

Decommissioning study of Forsmark NPP

International Nuclear Information System (INIS)

Anunti, Aake; Larsson, Helena; Edelborg, Mathias

2013-06-01

By Swedish law it is the obligation of the nuclear power utilities to satisfactorily demonstrate how a nuclear power plant can be safely decommissioned and dismantled when it is no longer in service as well as calculate the estimated cost of decommissioning of the nuclear power plant. Svensk Kaernbraenslehantering AB (SKB) has been commissioned by the Swedish nuclear power utilities to meet the requirements of current legislation by studying and reporting on suitable technologies and by estimating the costs of decommissioning and dismantling of the Swedish nuclear power plants. The present report is an overview, containing the necessary information to meet the above needs, for the Forsmark NPP. Information is given for the plant about the inventory of materials and radioactivity at the time for final shutdown. A feasible technique for dismantling is presented and the waste management is described and the resulting waste quantities are estimated. Finally a schedule for the decommissioning phase is given and the costs associated are estimated as a basis for funding

Decommissioning study of Forsmark NPP

Energy Technology Data Exchange (ETDEWEB)

Anunti, Aake; Larsson, Helena; Edelborg, Mathias [Westinghouse Electric Sweden AB, Vaesteraas (Sweden)

2013-06-15

By Swedish law it is the obligation of the nuclear power utilities to satisfactorily demonstrate how a nuclear power plant can be safely decommissioned and dismantled when it is no longer in service as well as calculate the estimated cost of decommissioning of the nuclear power plant. Svensk Kaernbraenslehantering AB (SKB) has been commissioned by the Swedish nuclear power utilities to meet the requirements of current legislation by studying and reporting on suitable technologies and by estimating the costs of decommissioning and dismantling of the Swedish nuclear power plants. The present report is an overview, containing the necessary information to meet the above needs, for the Forsmark NPP. Information is given for the plant about the inventory of materials and radioactivity at the time for final shutdown. A feasible technique for dismantling is presented and the waste management is described and the resulting waste quantities are estimated. Finally a schedule for the decommissioning phase is given and the costs associated are estimated as a basis for funding.

Rock-block characterization on regional to local scales for two SKB sites in Forsmark - Uppland and Laxemar - eastern Smaaland, south-eastern Sweden

International Nuclear Information System (INIS)

Beckholmen, Monica; Tiren, Sven A.

2010-11-01

Digital elevation data in 500m, 50m and 10m grids were used for rock-block interpretations at regional, semi-regional and local scales of areas around the two SKB sites, Forsmark and Laxemar, objects for the site-investigation programme. Both areas are interpreted to be close to the surface of the sub- Cambrian peneplain and varying altitude and attitude may testify to blockfaulting in the distorted peneplain. Topographic breaks and changes in the gradient also reveal possible zones of weakness that may conduct water. Rock blocks were constructed for Uppland at 1:750 000, northern Uppland at 1:450 000 and the local Forsmark area at 1:150 000, three sets were constructed for eastern Smaaland at 1:500 000, and one for the semi-regional area at 1:250 000 and one for the local Laxemar area at 1:75 000. The orientation of rock-block boundaries and the size of the rock blocks were treated statistically. The rock blocks/polygons were analysed for their mean, minimum and maximum elevation and the range. The values were displayed by maps. The topography in especially eastern Smaaland is dominated by a clear gradient, the land rising from the sea in the east. Efforts were therefore made to remove an estimated gradient to assess the residual features and the same analyses were then made for mean, maximum, minimum and range values. In many cases the results were enhanced and the two types of presentations are complementary to each other. The rock-block interpretations were compared to bedrock and general correlation between major structures where identified. However, the distribution of rocks on a regional map often demonstrates the plastic deformation in a wider zone. Earthquake epicentres were combined with the rock-block maps and assuming that interpreted rock-block boundaries are fairly steep, there is good agreement between the location of epicentres and rock-block boundaries. In some cases it can be seen how seismic disturbance migrated along a structure. Many

Rock-block characterization on regional to local scales for two SKB sites in Forsmark - Uppland and Laxemar - eastern Smaaland, south-eastern Sweden

Energy Technology Data Exchange (ETDEWEB)

Beckholmen, Monica; Tiren, Sven A. (GEOSIGMA AB (Sweden))

2010-11-15

Digital elevation data in 500m, 50m and 10m grids were used for rock-block interpretations at regional, semi-regional and local scales of areas around the two SKB sites, Forsmark and Laxemar, objects for the site-investigation programme. Both areas are interpreted to be close to the surface of the sub- Cambrian peneplain and varying altitude and attitude may testify to blockfaulting in the distorted peneplain. Topographic breaks and changes in the gradient also reveal possible zones of weakness that may conduct water. Rock blocks were constructed for Uppland at 1:750 000, northern Uppland at 1:450 000 and the local Forsmark area at 1:150 000, three sets were constructed for eastern Smaaland at 1:500 000, and one for the semi-regional area at 1:250 000 and one for the local Laxemar area at 1:75 000. The orientation of rock-block boundaries and the size of the rock blocks were treated statistically. The rock blocks/polygons were analysed for their mean, minimum and maximum elevation and the range. The values were displayed by maps. The topography in especially eastern Smaaland is dominated by a clear gradient, the land rising from the sea in the east. Efforts were therefore made to remove an estimated gradient to assess the residual features and the same analyses were then made for mean, maximum, minimum and range values. In many cases the results were enhanced and the two types of presentations are complementary to each other. The rock-block interpretations were compared to bedrock and general correlation between major structures where identified. However, the distribution of rocks on a regional map often demonstrates the plastic deformation in a wider zone. Earthquake epicentres were combined with the rock-block maps and assuming that interpreted rock-block boundaries are fairly steep, there is good agreement between the location of epicentres and rock-block boundaries. In some cases it can be seen how seismic disturbance migrated along a structure. Many

Well-construction and hydrogeologic data for observation wells in the vicinity of a low-level radioactive-waste disposal site near Sheffield, Illinois

Science.gov (United States)

Mansue, Lawrence J.; Mills, Patrick C.

1991-01-01

The U.S. Geological Survey conducted hydrogeologic studies at the low-level radioactive-waste disposal site near Sheffield, Illinois, from 1976 through 1987. During that period, 108 observation wells were installed in the vicinity of the disposal site in glacial and post-glacial deposits of Quaternary age and bedrock of Pennsylvanian age. Data in this report include the location of each well, the date each well was drilled, the geologic units penetrated by each well, the physical measurements of each well, the elevations of the top (measuring point) of each well and geologic-unit contacts at each well, and the highest and lowest recorded water levels in each well.

Education and Employment in Hydrogeology.

Science.gov (United States)

Pederson, Darryll T.

1987-01-01

Reports on a study of position descriptions in the field of hydrogeology appearing in want ads, published studies describing the working professional, and published descriptions of hydrogeology programs. Results indicate an increase in positions of ten times that of five years ago. Suggests basic training requirements for beginning…

The typology of Irish hard-rock aquifers based on an integrated hydrogeological and geophysical approach

Science.gov (United States)

Comte, Jean-Christophe; Cassidy, Rachel; Nitsche, Janka; Ofterdinger, Ulrich; Pilatova, Katarina; Flynn, Raymond

2012-12-01

Groundwater flow in hard-rock aquifers is strongly controlled by the characteristics and distribution of structural heterogeneity. A methodology for catchment-scale characterisation is presented, based on the integration of complementary, multi-scale hydrogeological, geophysical and geological approaches. This was applied to three contrasting catchments underlain by metamorphic rocks in the northern parts of Ireland (Republic of Ireland and Northern Ireland, UK). Cross-validated surface and borehole geophysical investigations confirm the discontinuous overburden, lithological compartmentalisation of the bedrock and important spatial variations of the weathered bedrock profiles at macro-scale. Fracture analysis suggests that the recent (Alpine) tectonic fabric exerts strong control on the internal aquifer structure at meso-scale, which is likely to impact on the anisotropy of aquifer properties. The combination of the interpretation of depth-specific hydraulic-test data with the structural information provided by geophysical tests allows characterisation of the hydrodynamic properties of the identified aquifer units. Regionally, the distribution of hydraulic conductivities can be described by inverse power laws specific to the aquifer litho-type. Observed groundwater flow directions reflect this multi-scale structure. The proposed integrated approach applies widely available investigative tools to identify key dominant structures controlling groundwater flow, characterising the aquifer type for each catchment and resolving the spatial distribution of relevant aquifer units and associated hydrodynamic parameters.

A safety assessment approach using coupled NEAR3D and CHAN3D - Forsmark

Energy Technology Data Exchange (ETDEWEB)

Liu, Longcheng; Moreno, Luis; Neretnieks, Ivars (Dept. of Chemical Engineering and Technology, Royal Inst. of Technology, Stockholm (Sweden)); Gylling, Bjoern (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden))

2010-12-15

Safety assessment calculations for the Forsmark site were performed using a new code, which couples the far-field code CHAN3D and the near-field code NEAR3D. In addition, the package has a Graphical User Interface (GUI) and a code that governs the simulations (Coupling). The simulations were performed for 90 different canister locations, which were randomly chosen. Deterministic data were used for tunnels, deposition holes, and shafts. The background fractures were stochastically generated in two HRD realizations. The F-ratio and the water travel time distributions were used to study the performance of the simulations. Near-field calculations were not performed for the Forsmark site using the new coded presented in the prevailing report. However, the obtained results in this study are compared with the results from the Task 2 model of the ConnectFlow report /Joyce et al. 2010/. Although the results cannot be compared directly, a reasonably good agreement is obtained for the F-ratio

Expected extreme sea levels at Forsmark and Laxemar-Simpevarp up until year 2100

International Nuclear Information System (INIS)

Brydsten, Lars; Engqvist, Anders; Naeslund, Jens-Ove; Lindborg, Tobias

2009-01-01

Literature data on factors that can affect the highest expected shoreline during the operational lifetime of a final repository up until ca 2100 AD have been compiled for Forsmark and Laxemar/Simpevarp. The study takes into consideration eustasy (global sea level), isostasy (isostatic rebound) and their trends, as well as regional (North Sea) and local (Baltic Sea) annual extremes of today's sea levels and those in year 2100. The most uncertain factor of these is the future global sea level change. For this factor, three possible scenarios have been included from the literature, forming an rough uncertainty interval around a case with an 'intermediate' global sea level. To this end, the study thus makes use of information on global sea level change that has been published since the IPCC's (UN Intergovernmental Panel on Climate Change) most recent report (2007). The local cumulative impact on the shoreline of the eustatic and isostatic components for both the Forsmark and Laxemar/Simpevarp coastal areas is that the maximum sea level occurs at the end of the investigation period, by year 2100. The interaction of these estimates is discussed in terms of coastal oceanographic aspects and estimated return periods for local extreme sea level-impacting events, including estimated storm surge. Maximum sea levels in year 2100 based on the sea level rise estimates by Rahmstorf are + 254 cm for Forsmark and + 297 cm for Laxemar/Simpevarp, both of these levels with an uncertainty interval of about ± 70 cm. The numbers apply for the worst possible case in regard to future sea level rise, and for occasions of short duration during heavy storms. In this context it is important to note that the data on which these estimates are based are the subject of intense research, and that revisions are therefore to be expected

Expected extreme sea levels at Forsmark and Laxemar-Simpevarp up until year 2100

Energy Technology Data Exchange (ETDEWEB)

Brydsten, Lars (Umeaa Univ., Umeaa (Sweden)); Engqvist, Anders (Royal Institute of Technology, Stockholm (Sweden)); Naeslund, Jens-Ove; Lindborg, Tobias (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden))

2009-01-15

Literature data on factors that can affect the highest expected shoreline during the operational lifetime of a final repository up until ca 2100 AD have been compiled for Forsmark and Laxemar/Simpevarp. The study takes into consideration eustasy (global sea level), isostasy (isostatic rebound) and their trends, as well as regional (North Sea) and local (Baltic Sea) annual extremes of today's sea levels and those in year 2100. The most uncertain factor of these is the future global sea level change. For this factor, three possible scenarios have been included from the literature, forming an rough uncertainty interval around a case with an 'intermediate' global sea level. To this end, the study thus makes use of information on global sea level change that has been published since the IPCC's (UN Intergovernmental Panel on Climate Change) most recent report (2007). The local cumulative impact on the shoreline of the eustatic and isostatic components for both the Forsmark and Laxemar/Simpevarp coastal areas is that the maximum sea level occurs at the end of the investigation period, by year 2100. The interaction of these estimates is discussed in terms of coastal oceanographic aspects and estimated return periods for local extreme sea level-impacting events, including estimated storm surge. Maximum sea levels in year 2100 based on the sea level rise estimates by Rahmstorf are + 254 cm for Forsmark and + 297 cm for Laxemar/Simpevarp, both of these levels with an uncertainty interval of about +- 70 cm. The numbers apply for the worst possible case in regard to future sea level rise, and for occasions of short duration during heavy storms. In this context it is important to note that the data on which these estimates are based are the subject of intense research, and that revisions are therefore to be expected

Spatial bedrock erosion distribution in a natural gorge

Science.gov (United States)

Beer, A. R.; Turowski, J. M.; Kirchner, J. W.

2015-12-01

Quantitative analysis of morphological evolution both in terrestrial and planetary landscapes is of increasing interest in the geosciences. In mountainous regions, bedrock channel formation as a consequence of the interaction of uplift and erosion processes is fundamental for the entire surface evolution. Hence, the accurate description of bedrock channel development is important for landscape modelling. To verify existing concepts developed in the lab and to analyse how in situ channel erosion rates depend on the interrelations of discharge, sediment transport and topography, there is a need of highly resolved topographic field data. We analyse bedrock erosion over two years in a bedrock gorge downstream of the Gorner glacier above the town of Zermatt, Switzerland. At the study site, the Gornera stream cuts through a roche moutonnée in serpentine rock of 25m length, 5m width and 8m depth. We surveyed bedrock erosion rates using repeat terrestrial laser scanning (TLS) with an average point spacing of 5mm. Bedrock erosion rates in direction of the individual surface normals were studied directly on the scanned point clouds applying the M3C2 algorithm (Lague et al., 2013, ISPRS). The surveyed erosion patterns were compared to a simple stream erosivity visualisation obtained from painted bedrock sections at the study location. Spatially distributed erosion rates on bedrock surfaces based on millions of scan points allow deduction of millimeter-scale mean annual values of lateral erosion, incision and downstream erosion on protruding streambed surfaces. The erosion rate on a specific surface point is shown to depend on the position of this surface point in the channel's cross section, its height above the streambed and its spatial orientation to the streamflow. Abrasion by impacting bedload was likely the spatially dominant erosion process, as confirmed by the observed patterns along the painted bedrock sections. However, a single plucking event accounted for the half

Final disposal of spent nuclear fuel in Finnish bedrock. Olkiluoto site report

Energy Technology Data Exchange (ETDEWEB)

Anttila, P. [Fortum Engineering Oy, Vantaa (Finland); Ahokas, H. [Fintact Oy, Helsinki (Finland); Front, K. [VTT Communication and Infrastructure, Espoo (Finland)] [and others

1999-06-01

postglacial history of the island of Olkiluoto, which rose from the Baltic Sea some 2 500 - 3 000 years ago. The groundwater varies from modern fresh water near the surface to saline water at greater depths. Above 150 m current meteoric recharge and Baltic Sea water dominates. Below this a mixture of Litorina Sea water and glacial meltwater is dominant. Deeper below 500 m subglacial and older saline groundwater predominates. The maximum values for Total Dissolved Solids (TDS) and chloride content are 69.13 g/l and the 43 g/l, respectively. Reducing conditions are expected to exist at depth, which are favourable in terms of low radionuclide solubility and slow canister corrosion. Potentially suitable bedrock blocks have been identified at the site for locating a repository for spent fuel in the depth range of 400 - 700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones should be avoided when locating the deposition tunnels and disposal holes. In addition, the salinity of the groundwater will probably limit to some extent the types of constructional materials that can be used. (orig.) 323 refs.

Final disposal of spent nuclear fuel in Finnish bedrock. Olkiluoto site report

International Nuclear Information System (INIS)

Anttila, P.; Ahokas, H.; Front, K.

1999-06-01

history of the island of Olkiluoto, which rose from the Baltic Sea some 2 500 - 3 000 years ago. The groundwater varies from modern fresh water near the surface to saline water at greater depths. Above 150 m current meteoric recharge and Baltic Sea water dominates. Below this a mixture of Litorina Sea water and glacial meltwater is dominant. Deeper below 500 m subglacial and older saline groundwater predominates. The maximum values for Total Dissolved Solids (TDS) and chloride content are 69.13 g/l and the 43 g/l, respectively. Reducing conditions are expected to exist at depth, which are favourable in terms of low radionuclide solubility and slow canister corrosion. Potentially suitable bedrock blocks have been identified at the site for locating a repository for spent fuel in the depth range of 400 - 700 m. No significant geotechnical, hydrogeological and hydrogeochemical constraints have been found to its construction, although it is recommended that certain fracture zones should be avoided when locating the deposition tunnels and disposal holes. In addition, the salinity of the groundwater will probably limit to some extent the types of constructional materials that can be used. (orig.)

Bedrock Geologic Map of the Hinesburg Quadrangle, Vermont

Data.gov (United States)

Vermont Center for Geographic Information — Digital Data from Thompson, P., Thompson, T.B., and Doolan, B., 2004, Bedrock Geology of the Hinesburg quadrangle, Vermont. The bedrock geologic map data at a scale...

Epilithic algal assemblages in the Forsmark Biotest basin

Energy Technology Data Exchange (ETDEWEB)

Snoeijs, P.

1987-04-01

The Forsmark Biotest Basin is an artificial offshore brackish lake, through which the cooling water is led from the Forsmark Nuclear Power Station on the Swedish east coast. The Biotest Basin differs from the Bothnian Sea surrounding it by a temperature elevation of up to 10 degrees C, no ice cover in winter, and an artificial, fast current. At 11 sites in- and outside the basin, benthic algal assemblages on stones in the hydrolittoral belt were sampled every third week during one year. Cover abundances were estimated for all algae occurring on the stones, but for diatoms only when they formed blooms. The results of the vegetation analyses are given. Diversity indices and dominance-diversity curves were computed for each site on the basis of pooled data for the cold season and for the rest of the year. The algae included both unicellular and multicellular forms. In total 88 taxa were distinguished in the species lists: 29 Cyanophyta, 7 Rhodophyta, 1 Chrysophyceae, 9 Fucophyceae, 17 Diatomophyceae and 25 Chlorophyta. In terms of percentage cover-abundance, blue-green and green algae increased with temperature, while red and brown algae and diatoms decreased with temperature in the interval between the minimum (0 degrees C) and the maximum (25.7 degrees C) water temperatures that were measured during the investigation period. Melosira spp. and Nitzschia filiformis proved to be the diatoms most favoured by the cooling water discharge. Lower diversity and greater dominance of one or a few species over the other was caused by thermal discharge at sites with fast-flowing water, but the opposite occurred at sites with quiescent water, mainly due to a greater number and higher abundances of blue-green algal species and thread-like green algae at the latter sites. This report also gives some notes on taxonomy of the encountered species.

Mechanical modelling of the Singoe deformation zone. Site descriptive modelling Forsmark stage 2.1

Energy Technology Data Exchange (ETDEWEB)

Glamheden, Rune; Maersk Hansen, Lars; Fredriksson, Anders; Bergkvist, Lars; Markstroem, Ingemar; Elfstroem, Mats [Golder Associates AB (Sweden)

2007-02-15

This project aims at demonstrating the theoretical approach developed by SKB for determination of mechanical properties of large deformation zones, in particular the Singoe deformation zone. Up to now, only bedrock and minor deformation zones have been characterized by means of this methodology, which has been modified for this project. The Singoe deformation zone is taken as a reference object to get a more comprehensive picture of the structure, which could be incorporated in a future version of the SDM of Forsmark. Furthermore, the Singoe Zone has been chosen because of available data from four tunnels. Scope of work has included compilation and analysis of geological information from site investigations and documentation of existing tunnels. Results have been analyzed and demonstrated by means of RVS-visualization. Numerical modelling has been used to obtain mechanical properties. Numerical modelling has also been carried out in order to verify the results by comparison of calculated and measured deformations. Compilation of various structures in the four tunnels coincides largely with a magnetic anomaly and also with the estimated width. Based on the study it is clear that the Singoe deformation zone has a heterogeneous nature. The number of fracture zones associated with the deformation zone varies on either side of the zone, as does the transition zone between host rock and the Singoe zone. The overall impression from the study is that the results demonstrate that the methodology used for simulating of equivalent mechanical properties is an applicable and adequate method, also in case of large deformation zones. Typical rock mechanical parameters of the Singoe deformations that can be used in the regional stress model considering the zone to be a single fracture are: 200 MPa/m in normal stiffness, 10-15 MPa/m in shear stiffness, 0.4 MPa in cohesion and 31.5 degrees in friction angle.

Mechanical modelling of the Singoe deformation zone. Site descriptive modelling Forsmark stage 2.1

International Nuclear Information System (INIS)

Glamheden, Rune; Maersk Hansen, Lars; Fredriksson, Anders; Bergkvist, Lars; Markstroem, Ingemar; Elfstroem, Mats

2007-02-01

This project aims at demonstrating the theoretical approach developed by SKB for determination of mechanical properties of large deformation zones, in particular the Singoe deformation zone. Up to now, only bedrock and minor deformation zones have been characterized by means of this methodology, which has been modified for this project. The Singoe deformation zone is taken as a reference object to get a more comprehensive picture of the structure, which could be incorporated in a future version of the SDM of Forsmark. Furthermore, the Singoe Zone has been chosen because of available data from four tunnels. Scope of work has included compilation and analysis of geological information from site investigations and documentation of existing tunnels. Results have been analyzed and demonstrated by means of RVS-visualization. Numerical modelling has been used to obtain mechanical properties. Numerical modelling has also been carried out in order to verify the results by comparison of calculated and measured deformations. Compilation of various structures in the four tunnels coincides largely with a magnetic anomaly and also with the estimated width. Based on the study it is clear that the Singoe deformation zone has a heterogeneous nature. The number of fracture zones associated with the deformation zone varies on either side of the zone, as does the transition zone between host rock and the Singoe zone. The overall impression from the study is that the results demonstrate that the methodology used for simulating of equivalent mechanical properties is an applicable and adequate method, also in case of large deformation zones. Typical rock mechanical parameters of the Singoe deformations that can be used in the regional stress model considering the zone to be a single fracture are: 200 MPa/m in normal stiffness, 10-15 MPa/m in shear stiffness, 0.4 MPa in cohesion and 31.5 degrees in friction angle

Iowa Bedrock Surface Elevation

Data.gov (United States)

Iowa State University GIS Support and Research Facility — This Digital Elevation Model (DEM) of the bedrock surface elevation in Iowa was compiled using all available data, principally information from GEOSAM, supplemented...

Hydrogeological study

International Nuclear Information System (INIS)

Massa, E.; Carrion, R.

1987-01-01

This work refers to the hydrogeological study about underground water to domestic uses. It was required by Artigas intendence of Uruguay, in the rural school 10, located belongs to the Chiflero zone around the capital of the Artigas Province.

Drilling technologies in hydrogeological survey

OpenAIRE

Vorlíček, Petr

2014-01-01

This work deals with the drilling technologies used in hydrogeology. The main aim of the work is to explore types of drilling technologies used at hydrogeological drilling wells and modern technologies that could potentially be used in the future. The work also summarizes a historical development of drilling techniques, a drilling process procedure, information obtained from boreholes and the most common types of drilling fluids.

A self-regulating model of bedrock river channel geometry

Science.gov (United States)

Stark, C. P.

2006-02-01

The evolution of many mountain landscapes is controlled by the incision of bedrock river channels. While the rate of incision is set by channel shape through its mediation of flow, the channel shape is itself set by the history of bedrock erosion. This feedback between channel geometry and incision determines the speed of landscape response to tectonic or climatic forcing. Here, a model for the dynamics of bedrock channel shape is derived from geometric arguments, a normal flow approximation for channel flow, and a threshold bed shear stress assumption for bedrock abrasion. The model dynamics describe the competing effects of channel widening, tilting, bending, and variable flow depth. Transient solutions suggest that channels may take ~1-10 ky to adapt to changes in discharge, implying that channel disequilibrium is commonplace. If so, landscape evolution models will need to include bedrock channel dynamics if they are to probe the effects of climate change.

Ogallala Bedrock Data Enhancement

Data.gov (United States)

Kansas Data Access and Support Center — This data set provides an enhanced estimate of the bedrock elevation of the Ogallala Aquifer in Kansas based on lithologic logs from a variety of sources. The data...

Role of Hydrogeology in Professional Environmental Projects

Science.gov (United States)

The purpose of this presentation is to acquaint hydrogeology students how hydrogeological principles are applied in environmental engineering projects. This presentation outlines EPA's Superfund processes of site characterization, feasibility studies, and remediation processes.

Hydrogeological testing in the Sellafield area

International Nuclear Information System (INIS)

Sutton, J.S.

1996-01-01

A summary of the hydrogeological test methodologies employed in the Sellafield geological investigations is provided in order that an objective appraisal of the quality of the data can be formed. A brief presentation of some of these data illustrates the corroborative nature of different test and measurement methodologies and provides a preliminary view of the results obtained. The programme of hydrogeological testing is an evolving one and methodologies are developing as work proceeds and targets become more clearly defined. As the testing is focused on relatively low permeability rocks at depth, the approach to testing differs slightly from conventional hydrogeological well testing and makes extensive use of oilfield technology. (author)

Final deposition of high-level nuclear waste in very deep boreholes. An evaluation based on recent research of bedrock conditions at great depths

International Nuclear Information System (INIS)

Aahaell, Karl-Inge

2007-01-01

This report evaluates the feasibility of very deep borehole disposal of high-level nuclear waste, e.g., spent nuclear fuel, in the light of recent technological developments and research on the characteristics of bedrock at extreme depths. The evaluation finds that new knowledge in the field of hydrogeology and technical advances in drilling technology have advanced the possibility of using very deep boreholes (3-5 km) for disposal of the Swedish nuclear waste. Decisive factors are (1) that the repository can be located in stable bedrock at a level where the groundwater is isolated from the biosphere, and (2) that the waste can be deposited and the boreholes permanently sealed without causing long-term disturbances in the density-stratification of the groundwater that surrounds the repository. Very deep borehole disposal might offer important advantage compared to the relatively more shallow KBS approach that is presently planned to be used by the Swedish nuclear industry in Sweden, in that it has the potential of being more robust. The reason for this is that very deep borehole disposal appears to permit emplacement of the waste at depths where the entire repository zone would be surrounded by stable, density-stratified groundwater having no contact with the surface, whereas a KBS-3 repository would be surrounded by upwardly mobile groundwater. This hydro-geological difference is a major safety factor, which is particularly apparent in all scenarios that envisage leakage of radioactive substances. Another advantage of a repository at a depth of 3 to 5 km is that it is less vulnerable to impacts from expected events (e.g., changes in groundwater conditions during future ice ages) as well as undesired events (e.g. such as terrorist actions, technical malfunction and major local earthquakes). Decisive for the feasibility of a repository based on the very deep borehole concept is, however, the ability to emplace the waste without failures. In order to achieve this

Cokriging surface elevation and seismic refraction data for bedrock topography

International Nuclear Information System (INIS)

Nyquist, J.E.; Doll, W.E.; Davis, R.K.; Hopkins, R.A.

1992-01-01

Analysis of seismic refraction data collected at a proposed site of the Advanced Neutron Source (ANS) Facility showed a strong correlation between surface and bedrock topography. By combining seismically determined bedrock elevation data with surface elevation data using cokriging, we were able to significantly improve our map of bedrock topography without collecting additional seismic data

REE and Y in groundwater in the upper 1.2 km of Proterozoic granitoids (Eastern Sweden) - Assessing the role of composition and origin of groundwaters, geochemistry of fractures, and organic/inorganic aqueous complexation

Science.gov (United States)

Mathurin, Frédéric A.; Åström, Mats E.; Drake, Henrik; Maskenskaya, Olga M.; Kalinowski, Birgitta E.

2014-11-01

Yttrium and rare earth elements (YREEs) are studied in groundwater in the shallow regolith aquifer and the fracture networks of the upper 1.2 km of Paleoproterozoic granitoids in boreal Europe (Laxemar and Forsmark areas, Sweden). The study includes groundwater sampled via a total of 34 shallow boreholes reaching the bottom of the regolith aquifer, and 72 deep boreholes with equipment designed for retrieval of representative groundwater at controlled depths in the fractured bedrock. The groundwater composition differs substantially between regolith and fracture groundwater and between areas, which affects the dissolved YREE features, including concentrations and NASC normalized patterns. In the fresh groundwater in the regolith aquifers, highest YREE concentrations occur (10th and 90th percentile; Laxemar: 4.4-82 μg L-1; Forsmark: 1.9-19 μg L-1), especially in the slightly acidic groundwater (pH: 6.3-7.2 - Laxemar), where the normalized YREE patterns are slightly enriched in light REEs (LaNASC/YNASC: 1.1-2.4). In the recharge areas, where redox potentials of the regolith groundwater is more moderate, negative Ce anomaly (Laxemar: 0.37-0.45; Forsmark: 0.15-0.92) and positive Y anomaly (mainly in Forsmark: 1.0-1.7) are systematically more pronounced than in discharge areas. The significant correlations between the YREE features and dissolved organic carbon, minor elements, and somewhat pH suggest a strong control of humic substances (HSs) together with Al rich colloids and redox sensitive Fe-Mn hydrous precipitates on the dissolved YREE pools. In the bedrock fractures, the groundwater is circumneutral to slightly basic and displays YREE concentrations that are at least one order of magnitude lower than the regolith groundwater, and commonly below detection limit in the deep brackish and saline groundwater, with some exceptions such as La and Y. At intermediate depth (>50 m), where groundwater of meteoric origin percolates, the LaNASC/YNASC values moderately to

Elemental composition of a deep sediment core from Lake Stocksjoen in the Forsmark area

Energy Technology Data Exchange (ETDEWEB)

Stroemgren, Maarten [Umeaa Univ. (Sweden). Dept. of Ecology and Environmental Sciences; Brunberg, Anna-Kristina [Uppsala Univ. (Sweden). Dept. of Ecology and Evolution/Limnology

2006-10-15

A deep sediment core was taken from Lake Stocksjoen, situated within the Forsmark site investigation area. The 55 cm long sediment core, representing the entire history of the lake (approx 430 years) was sliced in 5 cm portions and analysed for various chemical elements, using ICP-MS technique. In total, 54 different elements - classified as main elements, heavy metals and trace elements - were analysed. In general terms, three different patterns of stratigraphy were derived from all the analysed elements. Calcium, manganese, lead and mercury occurred in highest concentrations in the upper sediments (<30 cm depth). Phosphorus, zinc, cadmium, antimony, tin and strontium occurred in more even proportions throughout the sediment core. All the other elements were substantially reduced in the upper parts (<30 cm) compared to the deeper parts of the sediment core. Metals that are considered as airborne pollutants were found in low or moderate concentrations. This is in concert with other investigations of pollutants that have been performed in the Forsmark area. The sediment of Lake Stocksjoen is highly organic, and has been so during the entire history of the lake. Much of the organic Material seems to be refractory and less susceptible for mineralisation and respiration during the prevailing environmental conditions. This corresponds well with the characteristic gelatinous cyanophycee gyttja found in the lower parts of the sediment core. Although speculative, the pronounced changes in elemental composition of the sediment at 30 cm depth may correspond to the final isolation of the lake from the Baltic Sea, which occurred approximately 230 years ago. The deeper parts (below 30 cm depth) thus may represent the time period with regular intrusions of brackish water into the lake basin. One important factor governing the environmental conditions and the resulting elemental composition of the sediment is the unusually thick 'microbial mat', which is characteristic

SRS Geology/Hydrogeology Environmental Information Document

International Nuclear Information System (INIS)

Denham, M.E.

1999-01-01

The purpose of the Savannah River Site Geology and Hydrogeology Environmental Information Document (EID) is to provide geologic and hydrogeologic information to serve as a baseline to evaluate potential environmental impacts. This EID is based on a summary of knowledge accumulated from research conducted at the Savannah River Site (SRS) and surrounding areas

SRS Geology/Hydrogeology Environmental Information Document

Energy Technology Data Exchange (ETDEWEB)

Denham, M.E.

1999-08-31

The purpose of the Savannah River Site Geology and Hydrogeology Environmental Information Document (EID) is to provide geologic and hydrogeologic information to serve as a baseline to evaluate potential environmental impacts. This EID is based on a summary of knowledge accumulated from research conducted at the Savannah River Site (SRS) and surrounding areas.

Rock-block configuration in Uppland and the Aalands-hav basin, the regional surroundings of the SKB site in Forsmark, Sea and land areas, eastern Sweden

Energy Technology Data Exchange (ETDEWEB)

Beckholmen, Monica; Tiren, Sven A. (GEOSIGMA AB (Sweden))

2010-12-15

The Forsmark SKB site lies at the west-northwest trending shoreline in northern Uppland, sheltered from the sea by one of the larger islands in the Uppland archipelago, Graesoe. To assess the structures around Forsmark also in the sea area, the bottom structures of the Aalands-hav basin were investigated by means of depth readings from sea charts. Two rock-block maps with rock blocks at different scales were constructed and analysed for their top surface elevation. The topography in Uppland is more broken in the sea area east and northeast of Forsmark than it is on land. The major structure in the Aalands-hav basin is a westnorth- westerly line that passes southwest of Aaland, with a very steep gradient from the Aaland archipelago down to an exceptionally low sea-floor valley. On its southern side it rises in steps to a low flat basin divided into a deeper western half and a somewhat shallower eastern half. The deep west-north-westerly zone can be traced on-land past Oeregrund and Forsmark. West of Oeregrund however, the main trough swings into a north-northwesterly direction, just west of Graesoe. The southern border south of Oeregrund and Forsmark, shows a major drop in elevation northern side down. Forsmark thus lies on a ribbon with lower ground on both its southern and northern boundaries. This west-north-westerly belt is cut in two by a major north-south lineament that cuts through the archipelago between Aaland and Graesoe with a very deep canyon. This structure was seismically active in June 2006. The southern part of this line constitutes the western border of the low basin and has a steep gradient on its western side up to the Uppland mainland. The deep basin is filled with Jotnian metasediments. South of this basin, the Uppland mainland continues under water towards the east. South of Aaland an east-north-easterly ridge separates the low basin to the north from an east-west trending trough which is the eastern continuation of a major onland structure

Rock-block configuration in Uppland and the Aalands-hav basin, the regional surroundings of the SKB site in Forsmark, Sea and land areas, eastern Sweden

International Nuclear Information System (INIS)

Beckholmen, Monica; Tiren, Sven A.

2010-12-01

The Forsmark SKB site lies at the west-northwest trending shoreline in northern Uppland, sheltered from the sea by one of the larger islands in the Uppland archipelago, Graesoe. To assess the structures around Forsmark also in the sea area, the bottom structures of the Aalands-hav basin were investigated by means of depth readings from sea charts. Two rock-block maps with rock blocks at different scales were constructed and analysed for their top surface elevation. The topography in Uppland is more broken in the sea area east and northeast of Forsmark than it is on land. The major structure in the Aalands-hav basin is a westnorth- westerly line that passes southwest of Aaland, with a very steep gradient from the Aaland archipelago down to an exceptionally low sea-floor valley. On its southern side it rises in steps to a low flat basin divided into a deeper western half and a somewhat shallower eastern half. The deep west-north-westerly zone can be traced on-land past Oeregrund and Forsmark. West of Oeregrund however, the main trough swings into a north-northwesterly direction, just west of Graesoe. The southern border south of Oeregrund and Forsmark, shows a major drop in elevation northern side down. Forsmark thus lies on a ribbon with lower ground on both its southern and northern boundaries. This west-north-westerly belt is cut in two by a major north-south lineament that cuts through the archipelago between Aaland and Graesoe with a very deep canyon. This structure was seismically active in June 2006. The southern part of this line constitutes the western border of the low basin and has a steep gradient on its western side up to the Uppland mainland. The deep basin is filled with Jotnian metasediments. South of this basin, the Uppland mainland continues under water towards the east. South of Aaland an east-north-easterly ridge separates the low basin to the north from an east-west trending trough which is the eastern continuation of a major onland structure

Electrical Dynamic Simulation Activities in Forsmark NPP

International Nuclear Information System (INIS)

Lamell, Per

2015-01-01

The original power system analysis was done in the seventies in former ASEA AB software. For approximate twenty years no major new studies was done because of limited numbers of renewal projects. In the end of the nineties the plant started to update the selectivity planning and study of the loading of the safety bus-bars. The simulation and start of the development of simulation models was done in a tool named Simpow. Simpow was also an ASEA/ABB AB software developed from the program used in the seventies. To continue to work with Simpow was a decision made after doing an extensive review of on the marked available commercially software. Also at that time we start to do our first attempt building electrical simulation models of unit 1 and 2 according to the original documentation. The development of models for the unit 1, 2 and 3 became more intensive some years after the millennium. Partly because of event July 25, 2006 and also because of the renewal of unit 1 and 2 and had subsequently been initiated for unit 3 also. Today we have initiated a conversion of our models to a new program called PowerFactory. That due to the withdrawal of support and development on SIMPOW a couple of years ago. To development relevance, accuracy and detail, models are an important issue for FKA (Forsmark Kraftgrupp AB). The model is initially created according to the plant documentation and also including requested information from the original supplier. Continued development and updates of the model is done according to the data received from the contractors via the demands according to requirements in our technical documents on different electrical components in renewal projects. The development of the model is driven by known weaknesses, depending of the type of studies and necessary data related to events. An important part that will be described is to have a verified simulation tool and validated models. An example is that the models have been validated by making start and

Alluvial cover controlling the width, slope and sinuosity of bedrock channels

Science.gov (United States)

Turowski, Jens Martin

2018-02-01

Bedrock channel slope and width are important parameters for setting bedload transport capacity and for stream-profile inversion to obtain tectonics information. Channel width and slope development are closely related to the problem of bedrock channel sinuosity. It is therefore likely that observations on bedrock channel meandering yields insights into the development of channel width and slope. Active meandering occurs when the bedrock channel walls are eroded, which also drives channel widening. Further, for a given drop in elevation, the more sinuous a channel is, the lower is its channel bed slope in comparison to a straight channel. It can thus be expected that studies of bedrock channel meandering give insights into width and slope adjustment and vice versa. The mechanisms by which bedrock channels actively meander have been debated since the beginning of modern geomorphic research in the 19th century, but a final consensus has not been reached. It has long been argued that whether a bedrock channel meanders actively or not is determined by the availability of sediment relative to transport capacity, a notion that has also been demonstrated in laboratory experiments. Here, this idea is taken up by postulating that the rate of change of both width and sinuosity over time is dependent on bed cover only. Based on the physics of erosion by bedload impacts, a scaling argument is developed to link bedrock channel width, slope and sinuosity to sediment supply, discharge and erodibility. This simple model built on sediment-flux-driven bedrock erosion concepts yields the observed scaling relationships of channel width and slope with discharge and erosion rate. Further, it explains why sinuosity evolves to a steady-state value and predicts the observed relations between sinuosity, erodibility and storm frequency, as has been observed for meandering bedrock rivers on Pacific Arc islands.

Alluvial cover controlling the width, slope and sinuosity of bedrock channels

Directory of Open Access Journals (Sweden)

J. M. Turowski

2018-02-01

Full Text Available Bedrock channel slope and width are important parameters for setting bedload transport capacity and for stream-profile inversion to obtain tectonics information. Channel width and slope development are closely related to the problem of bedrock channel sinuosity. It is therefore likely that observations on bedrock channel meandering yields insights into the development of channel width and slope. Active meandering occurs when the bedrock channel walls are eroded, which also drives channel widening. Further, for a given drop in elevation, the more sinuous a channel is, the lower is its channel bed slope in comparison to a straight channel. It can thus be expected that studies of bedrock channel meandering give insights into width and slope adjustment and vice versa. The mechanisms by which bedrock channels actively meander have been debated since the beginning of modern geomorphic research in the 19th century, but a final consensus has not been reached. It has long been argued that whether a bedrock channel meanders actively or not is determined by the availability of sediment relative to transport capacity, a notion that has also been demonstrated in laboratory experiments. Here, this idea is taken up by postulating that the rate of change of both width and sinuosity over time is dependent on bed cover only. Based on the physics of erosion by bedload impacts, a scaling argument is developed to link bedrock channel width, slope and sinuosity to sediment supply, discharge and erodibility. This simple model built on sediment-flux-driven bedrock erosion concepts yields the observed scaling relationships of channel width and slope with discharge and erosion rate. Further, it explains why sinuosity evolves to a steady-state value and predicts the observed relations between sinuosity, erodibility and storm frequency, as has been observed for meandering bedrock rivers on Pacific Arc islands.

IN SITU MEASUREMENT OF BEDROCK EROSION

Directory of Open Access Journals (Sweden)

D. H. Rieke-Zapp

2012-07-01

Full Text Available While long term erosion rates of bedrock material may be estimated by dating methods, current day erosion rates are – if at all available – based on rough estimates or on point measurements. Precise quantification of short term erosion rates are required to improve our understanding of short term processes, for input in landscape evolution models, as well as for studying the mechanics and efficiency of different erosion processes in varying geomorphological settings. Typical current day erosion rates in the European Alps range from sub-millimetre to several millimetres per year depending on the dominant erosion processes. The level of surveying accuracy required for recurring sub-millimetre to millimetre measurements in the field is demanding. A novel surveying setup for in-situ measurement of bedrock erosion was tested recently in three different locations in Switzerland. Natural bedrock was investigated in the Gornera gorge close to Zermatt. Further on, bedrock samples were installed in exposed locations in the Erlenbach research watershed close to Einsiedeln, and in the Illgraben debris flow channel, located in the Canton Schwyz and Valais, respectively. A twofold measurement approach was chosen for all locations. For the first setup control points providing an absolute reference frame for recurrent measurements were embedded close to the area of interest. Close range photogrammetry was applied to measure surface changes on the bedrock samples. The precision for surface measurements in the field was 0.1 mm (1 σ and thus suitable for the application. The equipment needed for the surveys can easily be carried to the field. At one field site a structured light scanner was used along with the photogrammetric setup. Although the current generation of structured light scanners appeared less suitable for field application, data acquisition was much faster and checking the data for completeness in the field was straight forward. The latest

In Situ Measurement of Bedrock Erosion

Science.gov (United States)

Rieke-Zapp, D. H.; Beer, A.; Turowski, J. M.; Campana, L.

2012-07-01

While long term erosion rates of bedrock material may be estimated by dating methods, current day erosion rates are - if at all available - based on rough estimates or on point measurements. Precise quantification of short term erosion rates are required to improve our understanding of short term processes, for input in landscape evolution models, as well as for studying the mechanics and efficiency of different erosion processes in varying geomorphological settings. Typical current day erosion rates in the European Alps range from sub-millimetre to several millimetres per year depending on the dominant erosion processes. The level of surveying accuracy required for recurring sub-millimetre to millimetre measurements in the field is demanding. A novel surveying setup for in-situ measurement of bedrock erosion was tested recently in three different locations in Switzerland. Natural bedrock was investigated in the Gornera gorge close to Zermatt. Further on, bedrock samples were installed in exposed locations in the Erlenbach research watershed close to Einsiedeln, and in the Illgraben debris flow channel, located in the Canton Schwyz and Valais, respectively. A twofold measurement approach was chosen for all locations. For the first setup control points providing an absolute reference frame for recurrent measurements were embedded close to the area of interest. Close range photogrammetry was applied to measure surface changes on the bedrock samples. The precision for surface measurements in the field was 0.1 mm (1 σ) and thus suitable for the application. The equipment needed for the surveys can easily be carried to the field. At one field site a structured light scanner was used along with the photogrammetric setup. Although the current generation of structured light scanners appeared less suitable for field application, data acquisition was much faster and checking the data for completeness in the field was straight forward. The latest generation of compact

Removal of groundwater from final repository in Forsmark. Description of consequences for nature values and forest production; Bortledande av grundvatten fraan slutfoervarsanlaeggningen i Forsmark. Beskrivning av konsekvenser foer naturvaerden och skogsproduktion

Energy Technology Data Exchange (ETDEWEB)

Hamren, Ulrika; Collinder, Per; Allmer, Johan (Ekologigruppen AB (Sweden))

2010-11-15

The Swedish Nuclear Fuel and Waste Management Co (SKB) has chosen Forsmark in the Municipality of Oesthammar as site for the final repository for spent nuclear fuel. This report describes consequences for nature values and forestry due to groundwater diversion during construction and operation of the repository. The report concerns nature values that depend on, or are favoured by, a groundwater table close to or above the ground surface

Revising the security organisation at Forsmark NPP - A case study from the point of view of the operator and the regulatory and supervisory authority

International Nuclear Information System (INIS)

Roeden, B.; Strandberg, L.; Isaksson, S.

2001-01-01

Forsmark Nuclear Power Plant consists of three reactor-units. Each unit has separate shift crews and separate control rooms for operation of the plant. During 1996, Forsmarks Kraftgrupp AB (FKA) decided to change the organisation of Security at the site in Forsmark, Sweden. Reasons for changing the Organisation Experiences pointed out that it was necessary to have a Security supervisor present at site 24 hours per day. Experiences were basically gained from occasions when malfunctions in the technical security systems occurred. Another experience was that the procedures describing counter measures to different malfunctions in the technical security systems, did not meet the same high requirements, that would be expected in comparison with the Standard Operational and Emergency Operational Procedures, which are used for operation of the Nuclear Power Plant. It was decided to integrate the Security guards in the shift crew, one guard for each reactor unit and shift. Some of the regular Field Operators in the shift-crews for operating the plant were educated to competent Security Guards. The Shift Supervisor on each reactor unit became in charge for one Security Guard. One of the units also became in charge of the Security Central and the Security Guard operating the technical security systems. During incidents the supervisor from the fire brigade takes the responsibility for the security. He also has additionally two Security Guards at disposal from the fire brigade. In case of a major incident, this arrangement let the Shift Supervisors proceed taking the necessary counter measures concerning the process in the power plant. The attitude to new duties among the regular Field Operators educated to Security Guards were not positive, this problem affected also the attitude among the Shift supervisors. It was difficult to bring the different reactor units to work in the same direction and at the same time, generally speaking. The procedures and standards at each unit

The terrestrial ecosystems at Forsmark and Laxemar-Simpevarp. SR-Site Biosphere

Energy Technology Data Exchange (ETDEWEB)

Loefgren, Anders [ed.; EcoAnalytica, Haegersten (Sweden)

2010-12-15

The ecosystem is in most cases the link between radionuclides released from a repository and the exposure of humans and other biota to them. This report describes the terrestrial ecosystems in the Forsmark and Laxemar-Simpevarp areas by summarizing and performing cross-disciplinary analyses of data from a large number of reports produced during the site investigations, Figure 1-2. The report describes the terrestrial landscape, divided here into the three main categories: forests, wetlands and agriculture land, by identifying properties that are important for element accumulation and transport

The terrestrial ecosystems at Forsmark and Laxemar-Simpevarp. SR-Site Biosphere

International Nuclear Information System (INIS)

Loefgren, Anders

2010-12-01

The ecosystem is in most cases the link between radionuclides released from a repository and the exposure of humans and other biota to them. This report describes the terrestrial ecosystems in the Forsmark and Laxemar-Simpevarp areas by summarizing and performing cross-disciplinary analyses of data from a large number of reports produced during the site investigations, Figure 1-2. The report describes the terrestrial landscape, divided here into the three main categories: forests, wetlands and agriculture land, by identifying properties that are important for element accumulation and transport

Chemical conditions in present and future ecosystems in Forsmark - implications for selected radionuclides in the safety assessment SR-Site

International Nuclear Information System (INIS)

Troejbom, Mats; Grolander, Sara

2010-12-01

This report is a background report for the biosphere analysis of the SR-Site Safety Assessment. This work aims to describe the future development of the chemical conditions at Forsmark, based on the present chemical conditions at landscape level taking landscape development and climate cases into consideration. The results presented contribute to the overall understanding of the present and future chemistry in the Forsmark area, and specifically, to the understanding of the behaviour of some selected radionuclides in the surface system. The future development of the chemistry at the site is qualitatively discussed with focus on the interglacial within the next 10,000 years. The effects on the chemical environment of future climate cases as Global Warming and cold permafrost climates are also briefly discussed. The work is presented in two independent parts describing background radionuclide activities in the Forsmark area and the distribution and behaviour of a large number of stable elements in the landscape. In a concluding section, implications of the future chemical environment of a selection of radionuclides important in the Safety Assessment are discussed based on the knowledge of stable elements. The broad range of elements studied show that there are general and expected patterns for the distribution and behaviour in the landscape of different groups of elements. Mass balances reveal major sources and sinks, pool estimations show where elements are accumulated in the landscape and estimations of time-scales give indications of the potential future development. This general knowledge is transferred to radionuclides not measured in order to estimate their behaviour and distribution in the landscape. It could be concluded that the future development of the chemical environment in the Forsmark area might affect element specific parameters used in de radionuclide model in different directions depending on element. The alternative climate cases, Global Warming

Chemical conditions in present and future ecosystems in Forsmark - implications for selected radionuclides in the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

Troejbom, Mats (Mats Troejbom Konsult AB (Sweden)); Grolander, Sara (Facilia AB (Sweden))

2010-12-15

This report is a background report for the biosphere analysis of the SR-Site Safety Assessment. This work aims to describe the future development of the chemical conditions at Forsmark, based on the present chemical conditions at landscape level taking landscape development and climate cases into consideration. The results presented contribute to the overall understanding of the present and future chemistry in the Forsmark area, and specifically, to the understanding of the behaviour of some selected radionuclides in the surface system. The future development of the chemistry at the site is qualitatively discussed with focus on the interglacial within the next 10,000 years. The effects on the chemical environment of future climate cases as Global Warming and cold permafrost climates are also briefly discussed. The work is presented in two independent parts describing background radionuclide activities in the Forsmark area and the distribution and behaviour of a large number of stable elements in the landscape. In a concluding section, implications of the future chemical environment of a selection of radionuclides important in the Safety Assessment are discussed based on the knowledge of stable elements. The broad range of elements studied show that there are general and expected patterns for the distribution and behaviour in the landscape of different groups of elements. Mass balances reveal major sources and sinks, pool estimations show where elements are accumulated in the landscape and estimations of time-scales give indications of the potential future development. This general knowledge is transferred to radionuclides not measured in order to estimate their behaviour and distribution in the landscape. It could be concluded that the future development of the chemical environment in the Forsmark area might affect element specific parameters used in de radionuclide model in different directions depending on element. The alternative climate cases, Global Warming

The role of bedrock groundwater in rainfall-runoff response at hillslope and catchment scales

Science.gov (United States)

Gabrielli, C. P.; McDonnell, J. J.; Jarvis, W. T.

2012-07-01

SummaryBedrock groundwater dynamics in headwater catchments are poorly understood and poorly characterized. Direct hydrometric measurements have been limited due to the logistical challenges associated with drilling through hard rock in steep, remote and often roadless terrain. We used a new portable bedrock drilling system to explore bedrock groundwater dynamics aimed at quantifying bedrock groundwater contributions to hillslope flow and catchment runoff. We present results from the Maimai M8 research catchment in New Zealand and Watershed 10 (WS10) at the H.J. Andrews Experimental Forest in Oregon, USA. Analysis of bedrock groundwater at Maimai, through a range of flow conditions, revealed that the bedrock water table remained below the soil-bedrock interface, indicating that the bedrock aquifer has minimal direct contributions to event-based hillslope runoff. However, the bedrock water table did respond significantly to storm events indicating that there is a direct connection between hillslope processes and the underlying bedrock aquifer. WS10 groundwater dynamics were dominated by fracture flow. A highly fractured and transmissive zone within the upper one meter of bedrock conducted rapid lateral subsurface stormflow and lateral discharge. The interaction of subsurface stormflow with bedrock storage directly influenced the measured hillslope response, solute transport and computed mean residence time. This research reveals bedrock groundwater to be an extremely dynamic component of the hillslope hydrological system and our comparative analysis illustrates the potential range of hydrological and geological controls on runoff generation in headwater catchments.

Hydrodynamics in Evaporate-Bearing Fine-Grained Successions Investigated through an Interdisciplinary Approach: A Test Study in Southern Italy—Hydrogeological Behaviour of Heterogeneous Low-Permeability Media

Directory of Open Access Journals (Sweden)

E. Petrella

2018-01-01

Full Text Available Messinian evaporates are widely distributed in the Mediterranean Sea as outcropping sediments in small marginal basins and in marine cores. Progressive filling of subbasins led to the formation of complex aquifer systems in different regions where hypersaline and fresh water coexist and interact in different manner. It also generates a significant diversification of groundwater hydrochemical signature and different microbial communities. In the case study, the hydrogeology and hydrochemistry of the whole system are influenced by good hydraulic connection between the shallower pyroclastic horizon and the underlying evaporate-bearing fine-grained Messinian succession. This is demonstrated by the merge of hydrogeological, chemical, isotopic, and microbiological data. No mixing with deep ascending waters has been observed. As shown by geophysical, hydraulic, and microbiological investigations, the hydraulic heterogeneity of the Messinian bedrock, mainly due to karstified evaporitic interstrata/lenses, causes the hydraulic head to significantly vary with depth. Somewhere, the head increases with the depth’s increase and artesian flow conditions are locally observed. Moreover, the metagenomic investigations demonstrated the existence of a poor hydraulic connection within the evaporate-bearing fine-grained succession at metric and decametric scales, therefore leading to a patchwork of geochemical (and microbiological subenvironments.

VT Biodiversity Project - Bedrock Classification

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This dataset is a five category, nine sub-category classification of the bedrock units appearing on the Centennial Geologic Map of Vermont. The...

Effectiveness evaluation of remote data application in hydrogeologic explorations

Energy Technology Data Exchange (ETDEWEB)

Burleshin, M I; Koloskova, V N

1981-01-01

Use of the information approach to evaluate the effectiveness of remote data in hydrogeologic cartography of Ustyurt is discussed. Space image, interval and final diagrams of hydrogeologic interpretation are represented like a communication channel. Using the information approach, quantitative evaluation is carried out, and hydrogeologic maps are compared (that, have been compiled by earth surface methods and via interpretation of remote data.

Uncertainty in geological and hydrogeological data

Directory of Open Access Journals (Sweden)

B. Nilsson

2007-09-01

Full Text Available Uncertainty in conceptual model structure and in environmental data is of essential interest when dealing with uncertainty in water resources management. To make quantification of uncertainty possible is it necessary to identify and characterise the uncertainty in geological and hydrogeological data. This paper discusses a range of available techniques to describe the uncertainty related to geological model structure and scale of support. Literature examples on uncertainty in hydrogeological variables such as saturated hydraulic conductivity, specific yield, specific storage, effective porosity and dispersivity are given. Field data usually have a spatial and temporal scale of support that is different from the one on which numerical models for water resources management operate. Uncertainty in hydrogeological data variables is characterised and assessed within the methodological framework of the HarmoniRiB classification.

HYDROGEOLOGIC CASE STUDIES

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

Thermal modelling. Preliminary site description. Forsmark area - version 1.2

Energy Technology Data Exchange (ETDEWEB)

Sundberg, Jan; Back, Paer-Erik; Bengtsson, Anna; Laendell, Maerta [Geo Innova AB, Linkoeping (Sweden)

2005-08-01

This report presents the thermal site descriptive model for the Forsmark area, version 1.2. The main objective of this report is to present the thermal modelling work where data has been identified, quality controlled, evaluated and summarised in order to make an upscaling to lithological domain level possible. The thermal conductivity at canister scale has been modelled for two different lithological domains (RFM029 and RFM012, both dominated by granite to granodiorite (101057)). A main modelling approach has been used to determine the mean value of the thermal conductivity. Two alternative/complementary approaches have been used to evaluate the spatial variability of the thermal conductivity at domain level. The thermal modelling approaches are based on the lithological model for the Forsmark area, version 1.2 together with rock type models constituted from measured and calculated (from mineral composition) thermal conductivities. Results indicate that the mean of thermal conductivity is expected to exhibit a small variation between the different domains, 3.46 W/(mxK) for RFM012 to 3.55 W/(mxK) for RFM029. The spatial distribution of the thermal conductivity does not follow a simple model. Lower and upper 95% confidence limits are based on the modelling results, but have been rounded of to only two significant figures. Consequently, the lower limit is 2.9 W/(mxK), while the upper is 3.8 W/(mxK). This is applicable to both the investigated domains. The temperature dependence is rather small with a decrease in thermal conductivity of 10.0% per 100 deg C increase in temperature for the dominating rock type. There are a number of important uncertainties associated with these results. One of the uncertainties considers the representative scale for the canister. Another important uncertainty is the methodological uncertainties associated with the upscaling of thermal conductivity from cm-scale to canister scale. In addition, the representativeness of rock samples is

Tono regional hydrogeological study project. Annual report 2004

International Nuclear Information System (INIS)

Iwatsuki, Teruki; Ota, Kunio; Takeuchi, Shinji; Amano, Kenji; Takeuchi, Ryuji; Saegusa, Hiromitsu; Osawa, Hideaki

2005-09-01

Tono Geoscience Center, Japan Nuclear Cycle Development Institute has been conducting a wide range of geoscientific research in order to build firm scientific and technological basis for the research and development of geological disposal. One of the geoscientific research programme is a Regional Hydrogeological Study (RHS) project in the Tono region, central Japan. This report mainly summarizes the results of research in DH-14 and DH-15 boreholes at Toki city and Mizunami city in fiscal year 2004 which were carried out to support and improve the results in fiscal year 2003. The research in the regional scale area shows the reliability of conceptual hydrogeological model and numerical simulation for the evaluation of regional hydrogeology. On the other hand, the geological and geophysical investigation, and borehole investigation during the surface-based investigations in the local scale area provide the pragmatic distribution of hydrogeological structure that may control regional groundwater hydrology. Hydrogeological simulations regarding the geological structure such as fault and hydrogeological property demonstrate the priority of investigation of geological structure for the evaluation of hydrogeology. The fault perpendicular to groundwater flow direction crucially affects on regional hydrology. Such fault is necessary to be investigated by priority. Hydrochemical investigation shows that chemical evolution process in this groundwater illustrated is mixing between groundwaters with different salinities. Principal component analysis and mass balance calculation reveal reliable chemistry of end-member waters for mixing. Regarding methodology development, the strategy and procedure of investigations are summarized based on the results of surface-based investigation. Moreover the multi interval monitoring system for water pressure and temperature has developed and started to monitor the in-situ condition of groundwater. The geology, geological structure, hydraulic

Hydrogeological investigation of Melendiz basin (Aksaray)

International Nuclear Information System (INIS)

Dogdu, M.S.

1995-01-01

Within the scope of this M.Sc, study entitled Hydrogeologic Investigation of Melendiz basin, the geological, hydrological, hydrogeological and hydrochemical features of a 600 km2 area have been studied and, 1/100.000 scale geological and hydrogeological maps have been prepared. Tetriary-Guaternary aged young volkanic rocks occupy nearly 80% (480 km2 ) of the area. The major aquifers are alluvium and andesite and basalt which are extensively fractured and jointed. Aquitard units comprise of ignimbirite, some of the andesites-basalts and formations that composes of limestone-sandstone-marl intercalations. The youngest geologic unit of the area, Hasandag volcanic ash formation, and also the tuffs have been indentified as aquiclude units. Mean areal precipitation, potential and real evapotranspiration rates and mean annual streamflow have been calculated on the basis of available data and, a hydrologic budget of the basin has been established. Hydrogeologic units have been classified as aquifer, aquitard and aquiclude with respect to their geohydrologic properties, field observations and the results of the pumping tests. On the other hand, hydrodynamic mechanism of the groundwater flow reaching major cold and thermal water discharges have also been explained. A hydrogeologic budget for the area covering Ciftlik township and its vicinity where extensively joint and fractured andesite-basalt and alluvial aquifers outcrop has been established. Major water points as thermal and cold springs, wells and streams have been sampled for major ion analysis. Beyond this, some water points have also been sampled for organic, trace,metal ald environmental isotropic analyses. Environmental isotope data of thermal springs point out a long-deep groundwater flow path

Chemical analysis of water in hydrogeology

International Nuclear Information System (INIS)

Flakova, R.; Zenisova, Z.; Seman, M.

2010-01-01

The aim of the monograph is to give complete information on the chemical analysis of water hydrogeology not only for the students program of Geology study (Bachelor degree study), Engineering Geology and Hydrogeology (Master's degree study) and Engineering Geology (doctoral level study), but also for students from other colleges and universities schools in Slovakia, as well as in the Czech Republic, dealing with the chemical composition of water and its quality, from different perspectives. The benefit would be for professionals with hydrogeological, water and environmental practices, who can find there all the necessary information about proper water sampling, the units used in the chemical analysis of water, expressing the proper chemical composition of water in its various parameters through classification of chemical composition of the water up to the basic features of physical chemistry at thermodynamic calculations and hydrogeochemical modelling.

Groundwater flow modelling of periods with temperate climate conditions - Laxemar

International Nuclear Information System (INIS)

Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Roberts, David; Swan, David; Gylling, Bjoern; Marsic, Niko; Rhen, Ingvar

2010-12-01

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Laxemar-Simpevarp site during temperate climate conditions as a comparison to corresponding modelling carried out for Forsmark /Joyce et al. 2010/. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a Hydrogeological base case (reference case conceptualisation) and then an examination of various areas of uncertainty within the current understanding by a series of model variants. The Hydrogeological base case models at three different scales, 'repository', 'site' and 'regional' make use of a discrete fracture network (DFN) and equivalent continuous porous medium (ECPM) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 15,000 AD. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

Groundwater flow modelling of periods with temperate climate conditions - Laxemar

Energy Technology Data Exchange (ETDEWEB)

Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Roberts, David; Swan, David (Serco Technical Consulting Services (United Kingdom)); Gylling, Bjoern; Marsic, Niko (Kemakta Konsult AB, Stockholm (Sweden)); Rhen, Ingvar (SWECO Environment AB, Falun (Sweden))

2010-12-15

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Laxemar-Simpevarp site during temperate climate conditions as a comparison to corresponding modelling carried out for Forsmark /Joyce et al. 2010/. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a Hydrogeological base case (reference case conceptualisation) and then an examination of various areas of uncertainty within the current understanding by a series of model variants. The Hydrogeological base case models at three different scales, 'repository', 'site' and 'regional' make use of a discrete fracture network (DFN) and equivalent continuous porous medium (ECPM) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 15,000 AD. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

Indirect estimations and spatial variation in leaf area index of coniferous, deciduous and mixed forest stands in Forsmark and Laxemar

International Nuclear Information System (INIS)

Tagesson, Torbern

2006-12-01

Two sites in Sweden are investigated for a potential deep repository of the nuclear waste, the Laxemar investigation area (57 deg 5 min N, 16 deg 7 min E) and the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). In the characterisation of these sites, development of site descriptive models is an important part. Leaves are the main surface were an exchange of matter and energy between the atmosphere and the biosphere takes place, and leaf area index (LAI) of the vegetation cover is an important variable correlated to a number of ecophysiological parameters and hereby an important parameter in ecosystem models. In the investigation areas, LAI of boreal and temperate ecosystems were therefore estimated indirectly through optical measurements using the LAI-2000 (LI-COR, Cambridge UK) and TRAC (Tracing Radiation and Architecture of Canopies). On average, measured maximum LAI was 3.40 in Laxemar and 3.43 in Forsmark; minimum LAI was 1.65 in Laxemar and 1.97 in Forsmark. Forest inventory data showed that LAI is positively correlated with basal area, stand height, stand volume and breast height tree diameter. For the coniferous stands, there was also a linearly negative relationship with age. In the Laxemar investigation area, there were no significant relationships for LAI with a satellite derived kNN (kNearest Neighbor) data set with stand height, stand volume and stand age. The kNN data set can therefore not be used to extrapolate measured LAI over the Laxemar investigation area. There were significant relationships between LAI and the normalized difference vegetation index (NDVI) for coniferous, deciduous and mixed forest stands in the Laxemar investigation area. A NDVI image could be used to extrapolate LAI over the entire investigation area. For the Forsmark investigation area, effective LAI for all stands were correlated to NDVI and this relationship could then be used for extrapolation. The effective LAI image was afterwards corrected for average

Indirect estimations and spatial variation in leaf area index of coniferous, deciduous and mixed forest stands in Forsmark and Laxemar

Energy Technology Data Exchange (ETDEWEB)

Tagesson, Torbern [Dept. of Physical Geography and Ecosystem Analysis, Lund Univ., Lund (Sweden)

2006-12-15

Two sites in Sweden are investigated for a potential deep repository of the nuclear waste, the Laxemar investigation area (57 deg 5 min N, 16 deg 7 min E) and the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). In the characterisation of these sites, development of site descriptive models is an important part. Leaves are the main surface were an exchange of matter and energy between the atmosphere and the biosphere takes place, and leaf area index (LAI) of the vegetation cover is an important variable correlated to a number of ecophysiological parameters and hereby an important parameter in ecosystem models. In the investigation areas, LAI of boreal and temperate ecosystems were therefore estimated indirectly through optical measurements using the LAI-2000 (LI-COR, Cambridge UK) and TRAC (Tracing Radiation and Architecture of Canopies). On average, measured maximum LAI was 3.40 in Laxemar and 3.43 in Forsmark; minimum LAI was 1.65 in Laxemar and 1.97 in Forsmark. Forest inventory data showed that LAI is positively correlated with basal area, stand height, stand volume and breast height tree diameter. For the coniferous stands, there was also a linearly negative relationship with age. In the Laxemar investigation area, there were no significant relationships for LAI with a satellite derived kNN (kNearest Neighbor) data set with stand height, stand volume and stand age. The kNN data set can therefore not be used to extrapolate measured LAI over the Laxemar investigation area. There were significant relationships between LAI and the normalized difference vegetation index (NDVI) for coniferous, deciduous and mixed forest stands in the Laxemar investigation area. A NDVI image could be used to extrapolate LAI over the entire investigation area. For the Forsmark investigation area, effective LAI for all stands were correlated to NDVI and this relationship could then be used for extrapolation. The effective LAI image was afterwards corrected for average

An inexpensive and portable drill rig for bedrock groundwater studies in headwater catchments

Science.gov (United States)

C. Gabrielli; J.J. McDonnell

2011-01-01

Bedrock groundwater dynamics in headwater catchments are poorly understood and poorly characterized. Here, we present an inexpensive and portable bedrock drilling system designed for use in remote locations. Our system is capable of drilling bedrock wells up to 11 m deep and 38 mm in diameter in a wide range of bedrock types. The drill consists of a lawn mower engine...

Review of possible correlations between in situ stress and PFL fracture transmissivity data at Forsmark

Energy Technology Data Exchange (ETDEWEB)

Martin, Derek (University of Alberta (United States)); Follin, Sven (SF GeoLogic AB (Sweden))

2011-11-15

In laboratory samples, the fracture transmissivity decreases significantly as the confining stress increases. While these experimental relationships are widely accepted and validated on laboratory samples, it is unknown if such relationships exist in situ or if these relationships can be scaled from the centimetre-scale laboratory tests to the metre-scale of in situ fractures. The purpose of this work is to assess the relationship between the structural-hydraulic data gathered in deep, cored boreholes at Forsmark and the in situ stress state acting on the these fractures. In conclusion, there does not appear to be sufficient evidence from these analyses to support the notion that the magnitude of the flow along the fractures at Forsmark is solely controlled by the in situ stress acting on the fracture. This should not be surprising because the majority of the fractures formed more than 1 billion years ago and the current in situ stress state has only been active for the past 12 million years. It is more likely that the transmissivity values are controlled by fracture roughness, open channels within the fracture, fracture stiffness and fracture infilling material

Materials of conference: Hydrogeological Problems of South-West Poland

International Nuclear Information System (INIS)

1996-01-01

Hydrogeological problems of South-west Poland is the collection of conference papers held in Szklarska Poreba on 20-22 June 1996. The materials have been gathered in three topical groups: water quality problems in hydrological cycle, regional hydrogeology of South-west Poland, theoretical problems and research methods in hydrogeology. More of performed articles have a interdisciplinary character taking into account the precipitation and surface water quality and their influence on ground water features

Hydrogeology of the basalts in the Uruguayan NW

International Nuclear Information System (INIS)

Hausman, A.; Fernandez, A.

1967-01-01

This work is about the hydrogeological aspects in the NW Uruguayan basaltic area. The results of this research are the main geological, morphological and hydrogeological aspects of the area as well as the characteristics and the color of the basalt and sandstones

Teaching hydrogeology: a review of current practice

Science.gov (United States)

Gleeson, T.; Allen, D. M.; Ferguson, G.

2012-07-01

Hydrogeology is now taught in a broad spectrum of departments and institutions to students with diverse backgrounds. Successful instruction in hydrogeology thus requires a variety of pedagogical approaches depending on desired learning outcomes and the background of students. We review the pedagogical literature in hydrogeology to highlight recent advances and analyze a 2005 survey among 68 hydrogeology instructors. The literature and survey results suggest there are only ~ 15 topics that are considered crucial by most hydrogeologists and > 100 other topics that are considered crucial by some hydrogeologists. The crucial topics focus on properties of aquifers and fundamentals of groundwater flow, and should likely be part of all undergraduate hydrogeology courses. Other topics can supplement and support these crucial topics, depending on desired learning outcomes. Classroom settings continue to provide a venue for emphasizing fundamental knowledge. However, recent pedagogical advances are biased towards field and laboratory instruction with a goal of bolstering experiential learning. Field methods build on the fundamentals taught in the classroom and emphasize the collection of data, data uncertainty, and the development of vocational skills. Laboratory and computer-based exercises similarly build on theory, and offer an opportunity for data analysis and integration. The literature suggests curricula at all levels should ideally balance field, laboratory, and classroom pedagogy into an iterative and integrative whole. An integrated, iterative and balanced approach leads to greater student motivation and advancement of theoretical and vocational knowledge.

Crosshole investigations: Hydrogeological results and interpretations

International Nuclear Information System (INIS)

Black, J.H.; Holmes, D.C.; Brightman, M.A.

1987-12-01

The Crosshole Programme was an integrated geophysical and hydrogeological study of a limited volume of rock (known as the Crosshole Site) within the Stripa mine. Borehole radar, borehole seismic and hydraulic methods were developed for specific application to fractured crystalline rock. The hydrogeological investigations contained both single borehole and crosshole test techniques. A novel technique, using a sinusoidal variation of pressure, formed the main method of crosshole testing and was assessed during the programme. The strategy of crosshole testing was strongly influenced by the results from the geophysical measurements. The longer term, larger scale hydrogeological response of the region was asessed by examining the variation of heads over the region. These were responding to the presence of an old drift. A method of overall assessment involving minimising the divergence from a homogeneous response yielded credible values of hydraulic conductivity for the rock as a whole. (orig./DG)

Investigation of discrete-fracture network conceptual model uncertainty at Forsmark

International Nuclear Information System (INIS)

Geier, Joel

2011-04-01

In the present work a discrete fracture model has been further developed and implemented using the latest SKB site investigation data. The model can be used for analysing the fracture network and to model flow through the rock in Forsmark. The aim has been to study uncertainties in the hydrological discrete fracture network (DFN) for the repository model. More specifically the objective has been to study to which extent available data limits uncertainties in the DFN model and how data that can be obtained in future underground work can further limit these uncertainties. Moreover, the effects on deposition hole utilisation and placement have been investigated as well as the effects on the flow to deposition holes

Study of hydrogeological and engineering-geological conditions of deposits

International Nuclear Information System (INIS)

1985-01-01

Methods for hydrogeological and engineering-geological studies are considered as a part of the complex works dUring eXploration of hydrogenic uranium deposits to develop them by Underground ieaching (UL). Problems are enumerated and peculiarities Of hydrogeologic and engipeering-geological works at different stages are outlined (prospeccing - evaluating works, preliminary and detailed survey). Attention is paid to boring and equipment for hydrogeological and engineering - geological boreholes. Testing-filtering works are described, the latter includes: evacuations, fulnesses ( forcings), and tests of fulness-evacuation. The problem on steady-state observations in boreholes and laboratory studies of rocks and underground waters is discussed. Geological and geophysical methods for evaluation of rock and ore filtering properties are presented. Necessity of hydrogeological zonation of deposits as applied to UL is marked

Hydrogeologic factors to be addressed in disposal guidelines

International Nuclear Information System (INIS)

Lafleur, D.W.; Raven, K.G.

1986-12-01

This report identifies the physical hydrogeologic factors that should be addressed for performance assessment of a radioactive waste disposal facility in plutonic rock. The hydrogeologic factors include theoretical methods, groundwater flow factors and solute transport parameters. Theoretical methods, including different deterministic and stochastic approaches for evaluating physical hydrogeolgic conditions, are evaluated with respect to data requirements, applications and limitations. Preferred methods for measurement and determination of the identified groundwater flow factors and solute transport parameters are discussed. A recommended set of procedures for reliable hydrogeologic characterization of a plutonic rock mass at both regional and site scales is also presented

Preliminary Test Results of Heshe Hydrogeological Experimental Well Station in Taiwan

Science.gov (United States)

Chuang, P.; Liu, C.; Lin, M.; Chan, W.; Lee, T.; Chia, Y.; Teng, M.; Liu, C.

2013-12-01

Safe disposal of radioactive waste is a critical issue for the development of nuclear energy. The design of final disposal system is based on the concept of multiple barriers which integrate the natural barriers and engineering barriers for long-term isolation of radioactive wastes. As groundwater is the major medium that can transport radionuclides to our living environment, it is essential to characterize groundwater flow at the disposal site. Taiwan is located at the boundary between the Eurasian plate and the Philippine Sea plate. Geologic formations are often fractured due to tectonic compression and extension. In this study, a well station for the research and development of hydrogeological techniques was established at the Experimental Forest of the National Taiwan University in central Taiwan. There are 10 testing wells, ranging in depth from 25 m to 100 m, at the station. The bedrock beneath the regolith is highly fractured mudstone. As fracture is the preferential pathway of the groundwater flow, the focus of in-situ tests is to investigate the location of permeable fractures and the connection of permeable fractures. Several field tests have been conducted, including geophysical logging, heat-pulse flowmeter, hydraulic test, tracer test and double packer test, for the development of advanced technologies to detect the preferential groundwater flow in fractured rocks.

Preventive maintenance at the Forsmark Nuclear Power Plant

International Nuclear Information System (INIS)

Danielsson, H.

1985-01-01

The maintenance system at the Forsmark Nuclear Power Plant began in 1975, and was drawn up in co-operation with other power stations within the control of the Swedish State Power Board. Preventive maintenance (PM) is part of the system and has been in operation since 1978. Great efforts have been made to build up the system and to gather input data. Since 1981, the system has been in continuous use; follow-ups and system and quality improvements in database contents have been carried out. Great effort has also been devoted to maintaining a high quality of database contents and to the interplay between the different PM measures. We believe that PM plays an important role in the safety and economic operation of the power station and that it is essential that interest in PM should exist at all levels of the power company. (author)

Urban hydrogeology in Indonesia: A highlight from Jakarta

Science.gov (United States)

Lubis, R. F.

2018-02-01

In many cities in the developing countries, groundwater is an important source of public water supply. The interaction between groundwater systems and urban environments has become an urgent challenge for many developing cities in the world, Indonesia included. Contributing factors are, but not limited to, the continuous horizontal and vertical expansion of cities, population growth, climate change, water scarcity and groundwater quality degradation. Jakarta as the capital city of Indonesia becomes a good example to study and implement urban hydrogeology. Urban hydrogeology is a science for investigating groundwater at the hydrological cycle and its change, water regime and quality within the urbanized landscape and zones of its impact. The present paper provides a review of urban groundwater studies in Jakarta in the context of urban water management, advances in hydrogeological investigation, monitoring and modelling since the city was established. The whole study emphasizes the necessity of an integrated urban groundwater management and development supporting hydrogeological techniques for urban areas.

Forsmark site investigation. Programme for long-term observations of geosphere and biosphere after completed site investigations

International Nuclear Information System (INIS)

2007-06-01

The site investigation at Forsmark was terminated the last of June, 2007. Hundreds of investigations have been conducted during a period of more than five years. Monitoring of a number of geoscientific parameters and biological objects has been one important part of the site investigation programme. Monitoring is defined as recurrent measurements of the same parameters/objects, so that time series are generated. Long-term monitoring of for example weather parameters, surface water discharge in brooks, and the groundwater head in a large number of boreholes has been conducted during the site investigations. Furthermore, repeated sampling of precipitation, surface water and groundwater in soil and rock for hydrochemical analyses has been carried out, and the groundwater flow in isolated borehole sections has been measured several times. Besides, some biological objects, for example rare bird species, have been invented each year of the site investigation. The measured parameters and the invented objects are characterized by a certain degree of time dependent variability, which is also site-specific. The aim of the monitoring is primarily to establish the 'undisturbed' conditions, the so called 'baseline'. If a deep repository is sited at Forsmark, many site-specific conditions will change, due to natural causes as well as to the construction works. Knowledge about the undisturbed conditions strengthens the ability to reveal and quantify such changes and to distinguish natural changes from those caused by the human activities. Another object of monitoring is to, by the study of the variability pattern of the monitored parameters, elevate the knowledge about the underlying, often complex causes governing the variations. In this way the description of site-specific conditions may be more precise and the prospects of modelling important processes are improved. After completion of the site investigations, a period of about two years will follow, when the investigation

Forsmark site investigation. Programme for long-term observations of geosphere and biosphere after completed site investigations

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-06-15

The site investigation at Forsmark was terminated the last of June, 2007. Hundreds of investigations have been conducted during a period of more than five years. Monitoring of a number of geoscientific parameters and biological objects has been one important part of the site investigation programme. Monitoring is defined as recurrent measurements of the same parameters/objects, so that time series are generated. Long-term monitoring of for example weather parameters, surface water discharge in brooks, and the groundwater head in a large number of boreholes has been conducted during the site investigations. Furthermore, repeated sampling of precipitation, surface water and groundwater in soil and rock for hydrochemical analyses has been carried out, and the groundwater flow in isolated borehole sections has been measured several times. Besides, some biological objects, for example rare bird species, have been invented each year of the site investigation. The measured parameters and the invented objects are characterized by a certain degree of time dependent variability, which is also site-specific. The aim of the monitoring is primarily to establish the 'undisturbed' conditions, the so called 'baseline'. If a deep repository is sited at Forsmark, many site-specific conditions will change, due to natural causes as well as to the construction works. Knowledge about the undisturbed conditions strengthens the ability to reveal and quantify such changes and to distinguish natural changes from those caused by the human activities. Another object of monitoring is to, by the study of the variability pattern of the monitored parameters, elevate the knowledge about the underlying, often complex causes governing the variations. In this way the description of site-specific conditions may be more precise and the prospects of modelling important processes are improved. After completion of the site investigations, a period of about two years will follow, when

SR-Site: Oxygen ingress in the rock at Forsmark during a glacial cycle

Energy Technology Data Exchange (ETDEWEB)

Sidborn, Magnus (Kemakta Konsult AB (Sweden)); Sandstroem, Bjoern (WSP Sverige AB (Sweden)); Tullborg, Eva-Lena (Terralogica AB (Sweden)); Salas, Joaquin; Maia, Flavia; Delos, Anne; Molinero, Jorge (Amphos21 (Spain)); Hallbeck, Lotta; Pedersen, Karsten (Microbial Analytics Sweden AB (Sweden))

2010-11-15

, oxygen content in the glacial melt water, and rock matrix transport resistance are presented for both the analytical and the numerical models. In the numerical calculations, the effect of O{sub 2} consuming reactions with reducing fracture infillings is also evaluated. The results from the oxygen ingress models in this report are presented, or can easily be expressed, as the oxygen concentration as a function of the flow-related transport resistance (F-factor) of the recharge flow paths. This allows for the coupling of the oxygen ingress models with available results from hydrogeological models that include calculated F-factors along recharge flow paths under different static conditions. In this report, recharge flow path F-factors are used for stationary 'snap-shots' of unfavourable glacial situations at Forsmark, where the ice front is assumed to halt over the repository footprint

SR-Site: Oxygen ingress in the rock at Forsmark during a glacial cycle

International Nuclear Information System (INIS)

Sidborn, Magnus; Sandstroem, Bjoern; Tullborg, Eva-Lena; Salas, Joaquin; Maia, Flavia; Delos, Anne; Molinero, Jorge; Hallbeck, Lotta; Pedersen, Karsten

2010-11-01

, oxygen content in the glacial melt water, and rock matrix transport resistance are presented for both the analytical and the numerical models. In the numerical calculations, the effect of O 2 consuming reactions with reducing fracture infillings is also evaluated. The results from the oxygen ingress models in this report are presented, or can easily be expressed, as the oxygen concentration as a function of the flow-related transport resistance (F-factor) of the recharge flow paths. This allows for the coupling of the oxygen ingress models with available results from hydrogeological models that include calculated F-factors along recharge flow paths under different static conditions. In this report, recharge flow path F-factors are used for stationary 'snap-shots' of unfavourable glacial situations at Forsmark, where the ice front is assumed to halt over the repository footprint

Water activities in Forsmark (Part II). The final disposal facility for spent fuel: water activities above ground

International Nuclear Information System (INIS)

Werner, Kent; Hamren, Ulrika; Collinder, Per; Ridderstolpe, Peter

2010-09-01

The construction of the repository for spent nuclear fuel in Forsmark is associated with a number of measures above ground that constitute water operations according to Chapter 11 in the Swedish Environmental Code. This report, which is an appendix to the Environmental Impact Assessment, describes these water operations, their effects and consequences, and planned measures

Mapping Bedrock Topography using Electromagnetic Profiling ...

African Journals Online (AJOL)

Mapping Bedrock Topography using Electromagnetic Profiling. ... will be constructed The area under study is within the Abakaliki Shales Geologic Formation. ... micaceous sandstone; micaceous siltstone, sandy shales and shelly limestone.

Description of climate, surface hydrology, and near-surface hydrogeology. Simpevarp 1.2

International Nuclear Information System (INIS)

Werner, Kent; Bosson, Emma; Berglund, Sten

2005-04-01

This report presents and evaluates the site investigations and primary data on meteorology, surface hydrology and near-surface hydrogeology that are available in the Simpevarp 1.2 'data freeze'. The main objective is to update the previous Simpevarp 1.1 description of the meteorological, surface hydrological and near-surface hydrogeological conditions in the Simpevarp area. Based on the Simpevarp 1.2 dataset, an updated conceptual and descriptive model of the surface and near-surface water flow conditions in the Simpevarp area is presented. In cases where site investigation data are not yet available, regional and/or generic data are used as input to the modelling. GIS- and process-based tools, used for initial quantitative flow modelling, are also presented. The objectives of this initial quantitative modelling are to illustrate, quantify and support the site descriptive model, and also to produce relevant input data to the ecological systems modelling within the SKB SurfaceNet framework.For the Simpevarp 1.2 model, the relevant site investigations include the establishment of one local meteorological station and surface-hydrological stations for discharge measurements, delineation and description of catchment areas, manual discharge measurements in water courses, slug tests in groundwater monitoring wells, and manual groundwater level measurements. In addition, other investigations have also contributed to the modelling, providing data on geometry (including topography), data from surface-based geological investigations and boreholes in Quaternary deposits, and data on the hydrogeological properties of the bedrock. The conceptual and descriptive modelling includes an identification and basic description of type areas, domains and interfaces between domains within the model area. The surface and near-surface flow system is described, including the assignment of hydrogeological properties to HSDs (Hydraulic Soil Domains) of Quaternary deposits based on a

Description of climate, surface hydrology, and near-surface hydrogeology. Simpevarp 1.2

Energy Technology Data Exchange (ETDEWEB)

Werner, Kent [SWECO VIAK AB/Golder Associates AB, Stockholm (Sweden); Bosson, Emma; Berglund, Sten [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

2005-04-01

This report presents and evaluates the site investigations and primary data on meteorology, surface hydrology and near-surface hydrogeology that are available in the Simpevarp 1.2 'data freeze'. The main objective is to update the previous Simpevarp 1.1 description of the meteorological, surface hydrological and near-surface hydrogeological conditions in the Simpevarp area. Based on the Simpevarp 1.2 dataset, an updated conceptual and descriptive model of the surface and near-surface water flow conditions in the Simpevarp area is presented. In cases where site investigation data are not yet available, regional and/or generic data are used as input to the modelling. GIS- and process-based tools, used for initial quantitative flow modelling, are also presented. The objectives of this initial quantitative modelling are to illustrate, quantify and support the site descriptive model, and also to produce relevant input data to the ecological systems modelling within the SKB SurfaceNet framework.For the Simpevarp 1.2 model, the relevant site investigations include the establishment of one local meteorological station and surface-hydrological stations for discharge measurements, delineation and description of catchment areas, manual discharge measurements in water courses, slug tests in groundwater monitoring wells, and manual groundwater level measurements. In addition, other investigations have also contributed to the modelling, providing data on geometry (including topography), data from surface-based geological investigations and boreholes in Quaternary deposits, and data on the hydrogeological properties of the bedrock. The conceptual and descriptive modelling includes an identification and basic description of type areas, domains and interfaces between domains within the model area. The surface and near-surface flow system is described, including the assignment of hydrogeological properties to HSDs (Hydraulic Soil Domains) of Quaternary deposits based on a

Digital bedrock geologic map of the Mount Snow & Readsboro quadrangles, Vermont

Data.gov (United States)

Vermont Center for Geographic Information — Digital Data from VG95-DM1 Ratcliffe, NM, 1995, Digital bedrock geologic map of the Mount Snow & Readsboro quadrangles, Vermont, scale 1:24000, The bedrock...

Flowing with the changing needs of hydrogeology instruction

Science.gov (United States)

Gleeson, T.; Allen, D. M.; Ferguson, G.

2012-01-01

Hydrogeology is now taught in a broad spectrum of departments and institutions to students with diverse backgrounds. Successful instruction in hydrogeology thus requires a variety of pedagogical approaches depending on desired learning outcomes and the diverse background of students. We review the pedagogical literature in hydrogeology to highlight recent advances and analyze a 2005 survey of 68 hydrogeology instructors. The literature and survey results suggest there are ~15 topics that are considered crucial by most hydrogeologists and >100 other topics that are considered crucial by some hydrogeologists. The crucial topics focus on properties of aquifers and fundamentals of groundwater flow, and should likely be part of all undergraduate hydrogeology courses. Other topics can supplement and support these crucial topics, depending on desired learning outcomes. Classroom settings continue to provide a venue for emphasizing fundamental knowledge. However, recent pedagogical advances are biased towards field and laboratory instruction with a goal of bolstering experiential learning. Field methods build on the fundamentals taught in the classroom and emphasize the collection of data, data uncertainty, and the development of vocational skills. Laboratory and computer-based exercises similarly build on theory, and offer an opportunity for data analysis and integration. The literature suggests curricula at all levels should ideally balance field, laboratory, and classroom pedagogy into an iterative and integrative whole. An integrated approach leads to greater student motivation and advancement of theoretical and vocational knowledge.

A basis for modelling of radionuclide flow in the Forsmark biotest basin

International Nuclear Information System (INIS)

Notter, M.; Snoeijs, P.; Argaerde, L.; Elert, M.

1987-01-01

Certain radionuclides are discharged together with the cooling water of Forsmark power station. Of these, Mn-54, Co-60, Zn-65 and Ag-110 m are easily detectable in the environment. This report gives a conceptual five-compartment model for the flows of radionuclides within the basin ecosystem. The available data from biological and radio-ecological investigations in the biotest basin were used to quantify the amounts of radionuclides in each of the reservoirs. The subsystem water-sediment-primary producers was pointed out to be the most interesting part of the ecosystem for studying radionuclides with mathematical modelling in the future. (orig./DG)

First measurement of ice-bedrock interface of alpine glaciers by cosmic muon radiography

Science.gov (United States)

Nishiyama, R.; Ariga, A.; Ariga, T.; Käser, S.; Lechmann, A.; Mair, D.; Scampoli, P.; Vladymyrov, M.; Ereditato, A.; Schlunegger, F.

2017-06-01

The shape of the bedrock underneath alpine glaciers bears vital information on the erosional mechanism related to the flow of ice. So far, several geophysical exploration methods have been proposed to map the bedrock topography though with limited accuracy. Here we illustrate the first results from a technology, called cosmic ray muon radiography, newly applied in glacial geology to investigate the bedrock geometry beneath the Aletsch Glacier situated in the Central Swiss Alps. For this purpose we installed new cosmic muon detectors made of emulsion films at three sites along the Jungfrau railway tunnel and measured the shape of the bedrock under the uppermost part of Aletsch Glacier (Jungfraufirn). Our results constrain the continuation of the bedrock-ice interface up to a depth of 50 m below the surface, where the bedrock underneath the glacier strikes NE-SW and dips at 45° ± 5°. This documents the first successful application of this technology to a glaciated environment.

Rate estimates for lateral bedrock erosion based on radiocarbon ages, Duck River, Tennessee

International Nuclear Information System (INIS)

Brakenridge, G.R.

1985-01-01

Rates of bedrock erosion in ingrown meandering rivers can be inferred from the location of buried relict flood-plain and river-bank surfaces, associated paleosols, and radiocarbon dates. Two independent methods are used to evaluate the long-term rates of limestone bedrock erosion by the Duck River. Radiocarbon dates on samples retrieved from buried Holocene flood-plain and bank surfaces indicate lateral migration of the river bank at average rates of 0.6-1.9 m/100 yr. Such rates agree with lateral bedrock cliff erosion rates of 0.5-1.4 m/100 yr, as determined from a comparison of late Pleistocene and modern bedrock cliff and terrace scarp positions. These results show that lateral bedrock erosion by this river could have occurred coevally with flood-plain and terrace formation and that the resulting evolution of valley meander bends carved into bedrock is similar in many respects to that of channel meanders cut into alluvium. 11 references, 5 figures

Basis for applying for exemption according to species protection regulation. Final repository for spent nuclear fuel at Forsmark; Underlag till ansoekan om dispens enligt artskyddsfoerordningen. Slutfoervar foer anvaent kaernbraensle i Forsmark

Energy Technology Data Exchange (ETDEWEB)

2011-02-15

SKB will submit applications for permits and admissibility under the Environmental Act and under the Nuclear Activities Act to construct and operate a disposal facility for spent nuclear fuel at Forsmark. In the final repository the spent nuclear fuel from Swedish nuclear power plants is placed in order to protect human health and the environment against harmful effects of ionizing radiation. Construction and operation of the disposal facility in Forsmark will make an impact, give effects and consequences for the natural environment. Utilization of land for the construction of the facility and the impact on ground water as a result of groundwater drainage is expected to have negative consequences for the species included in species protection regulation. Thus, the planned activity require exemption from species protection regulation (SFS 2007:845). The purpose of this document is to provide a basis for an application for exemption under 14 paragraph species protection regulation from the prohibitions of 4, 6, 7 and 8 paragraph species protection regulation. A basis for the exemption application is that the proposed activity is considered to have an 'overriding public interest' prescribed in 14 paragraph species protection regulation. The document reports the impact, effects and consequences of the planned activities on species covered in the species protection regulation. The impact on protected species can be divided into two categories: - Direct effects on protected species and their habitats by utilization of the land. - Indirect effects on protected species and their habitats in the drainage of groundwater and the effect on groundwater levels. The document also includes a description of planned actions to prevent, restrict and compensate for the effects and consequences that the activity may cause. By applying for an exemption under 14 paragraph species protection regulation in a separate order from the application for permit according to chapters 9

Basis for applying for exemption according to species protection regulation. Final repository for spent nuclear fuel at Forsmark; Underlag till ansoekan om dispens enligt artskyddsfoerordningen. Slutfoervar foer anvaent kaernbraensle i Forsmark

Energy Technology Data Exchange (ETDEWEB)

2011-02-15

SKB will submit applications for permits and admissibility under the Environmental Act and under the Nuclear Activities Act to construct and operate a disposal facility for spent nuclear fuel at Forsmark. In the final repository the spent nuclear fuel from Swedish nuclear power plants is placed in order to protect human health and the environment against harmful effects of ionizing radiation. Construction and operation of the disposal facility in Forsmark will make an impact, give effects and consequences for the natural environment. Utilization of land for the construction of the facility and the impact on ground water as a result of groundwater drainage is expected to have negative consequences for the species included in species protection regulation. Thus, the planned activity require exemption from species protection regulation (SFS 2007:845). The purpose of this document is to provide a basis for an application for exemption under 14 paragraph species protection regulation from the prohibitions of 4, 6, 7 and 8 paragraph species protection regulation. A basis for the exemption application is that the proposed activity is considered to have an 'overriding public interest' prescribed in 14 paragraph species protection regulation. The document reports the impact, effects and consequences of the planned activities on species covered in the species protection regulation. The impact on protected species can be divided into two categories: - Direct effects on protected species and their habitats by utilization of the land. - Indirect effects on protected species and their habitats in the drainage of groundwater and the effect on groundwater levels. The document also includes a description of planned actions to prevent, restrict and compensate for the effects and consequences that the activity may cause. By applying for an exemption under 14 paragraph species protection regulation in a separate order from the application for permit according to chapters 9 and 11

Report of comment to the Nuclear Power Inspectorate concerning the final waste repository at Forsmark (SFR)

International Nuclear Information System (INIS)

1983-04-01

The institute gives its support to the construction of the final depository of low and medium level radioactive waste at Forsmark. The main outline has been presented by the Swedish Nuclear Fuel Supply Company in their application. Prior to putting into operation necessary instructions have to be issued and prior to closing the depository its impact on the environment is to be examined. (G.B.)

The terrestrial ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM site

Energy Technology Data Exchange (ETDEWEB)

Loefgren, Anders [EcoAnalytica, Haegersten (Sweden); ed.

2008-12-15

This report describes the terrestrial ecosystems in the Forsmark and Laxemar-Simpevarp areas by summarizing ecological data and data from disciplines such as hydrology, quaternary geology and chemistry. The description therefore includes a number of different processes that drive element fluxes in the ecosystems, such as net primary production, heterotrophic respiration, transpiration, and horizontal transport from land to streams and lakes. Moreover, the human appropriation of the landscape is described with regard to land use and potential and actual utilization of food resources both today and in a historical perspective

The terrestrial ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM site

International Nuclear Information System (INIS)

Loefgren, Anders

2008-12-01

This report describes the terrestrial ecosystems in the Forsmark and Laxemar-Simpevarp areas by summarizing ecological data and data from disciplines such as hydrology, quaternary geology and chemistry. The description therefore includes a number of different processes that drive element fluxes in the ecosystems, such as net primary production, heterotrophic respiration, transpiration, and horizontal transport from land to streams and lakes. Moreover, the human appropriation of the landscape is described with regard to land use and potential and actual utilization of food resources both today and in a historical perspective

Hydrogeological investigation programmes: best practice. Proof of evidence

International Nuclear Information System (INIS)

Reeves, G.M.

1996-01-01

Proof of Evidence by an expert witness is presented in support of the case by Friends of the Earth (FOE) against the proposed construction by UK Nirex Ltd of an underground Rock Characterisation Facility (RCF) at a site in the Sellafield area. The RCF is part of an investigation by Nirex into a suitable site for an underground repository for the disposal of radioactive waste. The objections were raised at a Planning Inquiry in 1995. Drawing on best practice in hydrogeological investigation from case studies of groundwater assessment in the UK and the Canadian nuclear waste disposal programme, the hydrogeological monitoring work undertaken to date at Sellafield is found to be inadequate in both scope and duration. The lack of adequate equilibrium hydrogeological data is significant in its implications for the RCF both in terms of the effects on local water resources and the proposed repository. It is concluded, therefore, that the construction of the RCF should be postponed pending the establishment of the equilibrium hydrogeological regime. (10 figures; 33 references). (UK)

Bedrock Kd data and uncertainty assessment for application in SR-Site geosphere transport calculations

International Nuclear Information System (INIS)

Crawford, James

2010-12-01

The safety assessment SR-Site is undertaken to assess the safety of a potential geologic repository for spent nuclear fuel at the Forsmark and Laxemar sites. The present report is one of several reports that form the data input to SR-Site and contains a compilation of recommended K d data (i.e. linear partitioning coefficients) for safety assessment modelling of geosphere radionuclide transport. The data are derived for rock types and groundwater compositions distinctive of the site investigation areas at Forsmark and Laxemar. Data have been derived for all elements and redox states considered of importance for far-field dose estimates as described in /SKB 2010d/. The K d data are given in the form of lognormal distributions characterised by a mean (μ) and standard deviation (σ). Upper and lower limits for the uncertainty range of the recommended data are defined by the 2.5% and 97.5% percentiles of the empirical data sets. The best estimate K d value for use in deterministic calculations is given as the median of the K d distribution

High-resolution monitoring of fluvial bedrock erosion in a natural gorge

Science.gov (United States)

Beer, Alexander R.; Turowski, Jens M.

2014-05-01

Morphological evolution of terrestrial and planetary landscapes is of increasing interest in the geosciences. In mountainous regions stream development and stream shape as a consequence of the interaction of uplift and erosion is fundamental for surface formation. Bedrock stream sections are prevalent that are routings for water and sediments. Hence, the correct description of bedrock channel evolution is fundamental for landscape modelling. To analyse how in situ erosion rates depend on factors like discharge, sediment transport and topography, there is a need of highly resolved topographic field data that so far is not available. Here we present preliminary outcomes of a change detection study from the Gorner Gorge above Zermatt, Switzerland. The outflow of the Gorner glacier (the Gornera stream) is captured most of the time by a water intake for hydropower production. However this intake is flushed twice a day in summer to purge settled sediments. Then the Gornera, charged with erosive bedload, runs along its natural stream bed that cuts through a roche moutonnée. This bedrock section (25m long, 5m wide and 8m deep) was surveyed repeatedly twice a year benefiting from nearly dry bed conditions during water capturing. A Leica ScanStation C10 was used for capturing high density point clouds (aspired average point spacing 5mm) of the bedrock surfaces. Referencing each of the various scanning positions was conducted using Leica HDS targets attached to fixed anchor bolts in the bedrock, that were surveyed locally with a total station. Resulting DEMs were used to calculate DEMs of difference (DoDs) for the bedrock walls and a huge boulder residing on the gravel bed. Erosion rates are visualised and discussed in respect of to the local spatial arrangement of the bedrock to the stream flow and water level.

Graffiti for science: Qualitative detection of erosional patterns through bedrock erosion painting

Science.gov (United States)

Beer, Alexander R.; Kirchner, James W.; Turowski, Jens M.

2016-04-01

Bedrock erosion is a crucial constraint on stream channel incision, and hence whole landscape evolution, in steep mountainous terrain and tectonically active regions. Several interacting processes lead to bedrock erosion in stream channels, with hydraulic shear detachment, plucking, and abrasion due to sediment impacts generally being the most efficient. Bedrock topography, together with the sediment tools and cover effects, regulate the rate and spatial pattern of in situ surface change. Measurements of natural bedrock erosion rates are valuable for understanding the underlying process physics, as well as for modelling landscape evolution and designing engineered structures. However, quantifying spatially distributed bedrock erosion rates in natural settings is challenging and few such measurements exist. We studied spatial bedrock erosion in a 30m-long bedrock gorge in the Gornera, a glacial meltwater stream above Zermatt. This stream is flushed episodically with sediment-laden streamflow due to hydropower operations upstream, with negligible discharge in the gorge in between these flushing events. We coated several bedrock surface patches with environmentally safe, and water-insoluble outdoor paint to document the spatial pattern of surface abrasion, or to be more precise, to document its driving forces. During four consecutive years, the change of the painted areas was recorded repeatedly with photographs before the painting was renewed. These photographs visually documented the spatial patterns of vertical erosion (channel incision), of lateral erosion (channel widening) and of downstream-directed erosion (channel clearance). The observed qualitative patterns were verified through comparison to quantitative change detection analyses based on annual high-resolution terrestrial laser scanning surveys of the bedrock surfaces. Comparison of repeated photographs indicated a temporal cover effect and a general height limit of the tools effect above the streambed

Hydrogeology baseline study Aurora Mine

International Nuclear Information System (INIS)

1996-01-01

A baseline hydrogeologic study was conducted in the area of Syncrude's proposed Aurora Mine in order to develop a conceptual regional hydrogeologic model for the area that could be used to understand groundwater flow conditions. Geologic information was obtained from over 2,000 coreholes and from data obtained between 1980 and 1996 regarding water level for the basal aquifer. A 3-D numerical groundwater flow model was developed to provide quantitative estimates of the potential environmental impacts of the proposed mining operations on the groundwater flow system. The information was presented in the context of a regional study area which encompassed much of the Athabasca Oil Sands Region, and a local study area which was defined by the lowlands of the Muskeg River Basin. Characteristics of the topography, hydrology, climate, geology, and hydrogeology of the region are described. The conclusion is that groundwater flow in the aquifer occurs mostly in a westerly direction beneath the Aurora Mine towards its inferred discharge location along the Athabasca River. Baseflow in the Muskeg River is mostly related to discharge from shallow surficial aquifers. Water in the river under baseflow conditions was fresh, of calcium-carbonate type, with very little indication of mineralization associated with deeper groundwater in the Aurora Mine area. 44 refs., 5 tabs., 31 figs

The amount of glacial erosion of the bedrock

International Nuclear Information System (INIS)

Paasse, Tore

2004-11-01

The purpose of this study is to estimate an upper bound for the average erosion of fresh bedrock that can reasonably be expected during a glacial period or a single glaciation. The study is based on the assumption that classic sediments, formed by Scandinavian ice erosion during the Quaternary period, still exist within the formerly glaciated area or its periphery. The volume of these sediments thus constitutes the maximum average glacial erosion of bedrock within this area. This volume is calculated by estimating the thickness of the minerogenic Quaternary from well data in Sweden and Denmark and from seismic measurements in adjacent sea areas. The average thickness of the Quaternary deposits and other reogolith in the investigated area was estimated to 16 m. Assuming that the whole volume is the result of glacial erosion of fresh bedrock this corresponds to 12 m depth. However, a great part of the sediments may consist of glacially redistributed Tertiary regolith. As the amount of Tertiary regolith is uncertain the estimated maximum average glacial erosion rate in fresh bedrock is uncertain, and assuming that the total sediment volume is the result of glacial erosion leads to an overestimation of the glacial erosion depth. Considering this, the average glacial erosion during a full glacial period has been estimated to between 0.2 m and 4 m. If the extremes in the made assumptions are excluded the glacial erosion during a glacial cycle can be estimated to about 1 m

The amount of glacial erosion of the bedrock

Energy Technology Data Exchange (ETDEWEB)

Paasse, Tore [Geological Survey of Sweden, Uppsala (Sweden)

2004-11-01

The purpose of this study is to estimate an upper bound for the average erosion of fresh bedrock that can reasonably be expected during a glacial period or a single glaciation. The study is based on the assumption that classic sediments, formed by Scandinavian ice erosion during the Quaternary period, still exist within the formerly glaciated area or its periphery. The volume of these sediments thus constitutes the maximum average glacial erosion of bedrock within this area. This volume is calculated by estimating the thickness of the minerogenic Quaternary from well data in Sweden and Denmark and from seismic measurements in adjacent sea areas. The average thickness of the Quaternary deposits and other reogolith in the investigated area was estimated to 16 m. Assuming that the whole volume is the result of glacial erosion of fresh bedrock this corresponds to 12 m depth. However, a great part of the sediments may consist of glacially redistributed Tertiary regolith. As the amount of Tertiary regolith is uncertain the estimated maximum average glacial erosion rate in fresh bedrock is uncertain, and assuming that the total sediment volume is the result of glacial erosion leads to an overestimation of the glacial erosion depth. Considering this, the average glacial erosion during a full glacial period has been estimated to between 0.2 m and 4 m. If the extremes in the made assumptions are excluded the glacial erosion during a glacial cycle can be estimated to about 1 m.

HYDROGEOLOGICAL RELATIONS ON KARSTIFIED ISLANDS - VIS ISLAND CASE STUDY

Directory of Open Access Journals (Sweden)

Josip Terzić

2004-12-01

Full Text Available An approach to the hydrogeological investigations on Adriatic islands is presented on the Island of Vis case study. Infiltration, accumulation and discharge of the groundwater occur in karstified rock mass. Hydrogeological relations are mostly a consequence of the geological setting, because of the complete hydrogeologic barrier in Komiža bay, and relative barrier in the area of karst poljes. Significant research was performed in the 1999 – 2000 period aimed of better understanding of hydrogeological relations. These investigations, as well as reinterpretation of some previously known data, included structural geology, hydrogeology, hydrology and hydrochemistry. Approximate rock mass hydraulic conductivity calculation is also shown, as well as level of its usability in such terrain. Based on all these methods, it is possible to conclude that on the Island of Vis there is no saline water present underneath the entire island. There is only a saline water wedge which is formed on the top of relatively impermeable base rock, some few tens of meters under recent sea level. With such a model, and taking in account the hydrological balance, it is possible to conclude that there is possibility of higher amount of groundwater exploitation then it is today (the paper is published in Croatian.

Hydrogeology of the West Siberian Basin

International Nuclear Information System (INIS)

Foley, M.G.; Bradley, D.J.; Cole, C.R.

1996-01-01

Nuclear fuel cycle activities of the former Soviet Union (FSU) have resulted in extensive radioactive contaminant releases to the environment in western Siberia. We are developing three-dimensional numerical models of the hydrogeology and potential contaminant migration in the West Siberian Basin. We have assumed that ground-water flow in the West Siberian Basin is topographically driven, with recharge to the basin occurring in the highlands on the west, east, and south, and internal discharge localized in numerous river valleys and lakes that ultimately discharge north to the ocean. We are modeling the regional hydrogeology as three-dimensional, steady-state, saturated flow that is recharged from above. We acquired topographic, geologic, hydrostratigraphic, hydrogeologic, and water-balance data for the West Siberian Basin and constructed a regional water table. We correlated and combined 70 different rock types derived from published descriptions of West Siberian Basin rocks into 17 rock types appropriate for assignment of hydrogeologic properties on the basis of spatial heterogeneity and constituent (i.e., sand, silt, and clay) diversity. Examination of resulting three-dimensional assemblages of rock types showed that they were consistent with published and inferred paleogeography and depositional processes. Calibrating the basin's moisture balance (i.e., recharge and discharge) to the derived water table determined plausible input parameter values for unknowns such as hydraulic conductivities. The general directions of calculated ground-water flow suggest that major rivers act as discharge areas, with upwelling below the rivers extending down into the basement rocks, and that ground-water divides that penetrate the entire thickness of the model are evident between major rivers

Hydrogeological Properties of the Rocks in Adansi Mining Area ...

African Journals Online (AJOL)

The hydrogeological properties of an aquifer coupled with climatic conditions and geomorphology determines how much groundwater exists in that location. A hydrogeological study of the rocks in the Adansi area was carried out to obtain the aquifer hydraulic properties. Drilling and pumping test analysis information were ...

SRP Baseline Hydrogeologic Investigation, Phase 3

Energy Technology Data Exchange (ETDEWEB)

Bledsoe, H.W.

1988-08-01

The SRP Baseline Hydrogeologic Investigation was implemented for the purpose of updating and improving the knowledge and understanding of the hydrogeologic systems underlying the SRP site. Phase III, which is discussed in this report, includes the drilling of 7 deep coreholes (sites P-24 through P-30) and the installation of 53 observation wells ranging in depth from approximately 50 ft to more than 970 ft below the ground surface. In addition to the collection of geologic cores for lithologic and stratigraphic study, samples were also collected for the determination of physical characteristics of the sediments and for the identification of microorganisms.

Bedrock model of the Romuvaara area

International Nuclear Information System (INIS)

Saksa, P.; Paananen, M.; Paulamaeki, S.; Anttila, P.; Pitkaenen, P.; Front, K.; Vaittinen, T.

1992-05-01

Site for the final disposal of the spent nuclear fuel investigations implemented in accordance with the research programme drawn up by Teollisuuden Voima Oy were carried out at Romuvaara, Kuhmo, in 1987 - 1991. Model of the site were compiled and used for describing the rock types, fractures, fracturing structures and geohydrological conditions, the main emphasis being on the examination of the bedrock fracturing and related hydraulic conductivity. Three-dimensional models were used for the classification of the various properties of the bedrock structures. The descriptive models were gathered together in a computerized system to facilitate illustration and strage. The rock types at Romuvaara are gneiss, mica gneiss, leucotonalite gneiss, amphibolite, granodiorite and metadiabase. The structural model for fracturing at the site contains 19 zones described in terms of a number of properties. The fracturing observed at Romuvaara ranges from local occurences of dence fracturing to significant, altered fracture zones. The structural model includes deduced values for hydraulic conductivity, deduced points of flow in the boreholes and measured hydraulic heads.Various classifications were used for assessment of hydraulic conductivity in the zones and solid bedrock, and in both cases conductivity was found to diminish with depth. Measured hydraulic heads were mostly found to support structural interpretation. The results were used for estimation of a three-dimensional hydraulic head distribution. Results from pumping tests carried out in the significant flow zone support the geometric interpretation

Expert panel on hydrogeology; report to AECL Research (1992)

International Nuclear Information System (INIS)

Domenico, P.A.; Grisak, G.E.; Schwartz, F.W.

1995-02-01

In 1992 AECL Research convened a panel of external hydrogeological experts consisting of P.A. Domenico, G.E. Grisak, and F.W. Schwartz, to review AECL's proposed approach to siting a geological repository in the rocks of the Canadian Shield for the safe disposal of Canada's nuclear fuel wastes. In particular the panel was asked to provide its opinion on 1) the soundness of the technical approach developed to characterize the groundwater flow systems for the purpose of selecting a location for a disposal vault, 2) the validity and effectiveness of the geological case study used to demonstrate the performance assessment methodology based on the hydrogeological conditions observed at the Whiteshell Research Area, and 3) the adequacy of the hydrogeological information that AECL proposes to use in its Environmental Impact Statement (EIS) of the disposal concept. This report presents the findings, conclusions and recommendations of the hydrogeology review panel. The report was submitted to AECL Research in 1992 December. (author). 24 refs., 2 tabs., 4 figs

2D soil and engineering-seismic bedrock modeling of eastern part of Izmir inner bay/Turkey

Science.gov (United States)

Pamuk, Eren; Akgün, Mustafa; Özdağ, Özkan Cevdet; Gönenç, Tolga

2017-02-01

Soil-bedrock models are used as a base when the earthquake-soil common behaviour is defined. Moreover, the medium which is defined as bedrock is classified as engineering and seismic bedrock in itself. In these descriptions, S-wave velocity is (Vs) used as a base. The mediums are called soil where the Vs is bedrock as well. Additionally, the parts are called engineering bedrock where the Vs is between 3000 m/s and 760 m/s, the parts where are bigger than 3000 m/s called seismic bedrock. The interfacial's horizontal topography where is between engineering and seismic bedrock is effective on earthquake's effect changing on the soil surface. That's why, 2D soil-bedrock models must be used to estimate the earthquake effect that could occur on the soil surface. In this research, surface wave methods and microgravity method were used for occuring the 2D soil-bedrock models in the east of İzmir bay. In the first stage, velocity values were obtained by the studies using surface wave methods. Then, density values were calculated from these velocity values by the help of the empiric relations. 2D soil-bedrock models were occurred based upon both Vs and changing of density by using these density values in microgravity model. When evaluating the models, it was determined that the soil is 300-400 m thickness and composed of more than one layers in parts where are especially closer to the bay. Moreover, it was observed that the soil thickness changes in the direction of N-S. In the study area, geologically, it should be thought the engineering bedrock is composed of Bornova melange and seismic bedrock unit is composed of Menderes massif. Also, according to the geophysical results, Neogene limestone and andesite units at between 200 and 400 m depth show that engineering bedrock characteristic.

Hydrogeology of the Mogollon Highlands, central Arizona

Science.gov (United States)

Parker, John T.C.; Steinkampf, William C.; Flynn, Marilyn E.

2005-01-01

The Mogollon Highlands, 4,855 square miles of rugged, mountainous terrain at the southern edge of the Colorado Plateau in central Arizona, is characterized by a bedrock-dominated hydrologic system that results in an incompletely integrated regional ground-water system, flashy streamflow, and various local water-bearing zones that are sensitive to drought. Increased demand on the water resources of the area as a result of recreational activities and population growth have made necessary an increased understanding of the hydrogeology of the region. The U.S. Geological Survey conducted a study of the geology and hydrology of the region in cooperation with the Arizona Department of Water Resources under the auspices of the Arizona Rural Watershed Initiative, a program launched in 1998 to assist rural areas in dealing with water-resources issues. The study involved the analysis of geologic maps, surface-water and ground-water flow, and water and rock chemical data and spatial relationships to characterize the hydrogeologic framework. The study area includes the southwestern corner of the Colorado Plateau and the Mogollon Rim, which is the eroded edge of the plateau. A 3,000- to 4,000-foot sequence of early to late Paleozoic sedimentary rocks forms the generally south-facing scarp of the Mogollon Rim. The area adjacent to the edge of the Mogollon Rim is an erosional landscape of rolling, step-like terrain exposing Proterozoic metamorphic and granitic rocks. Farther south, the Sierra Ancha and Mazatzal Mountain ranges, which are composed of various Proterozoic rocks, flank an alluvial basin filled with late Cenozoic sediments and volcanic flows. Eight streams with perennial to intermittent to ephemeral flow drain upland regions of the Mogollon Rim and flow into the Salt River on the southern boundary or the Verde River on the western boundary. Ground-water flow paths generally are controlled by large-scale fracture systems or by karst features in carbonate rocks. Stream

Bedrock Geologic Map of Vermont - Dikes

Data.gov (United States)

Vermont Center for Geographic Information — The bedrock geology was last mapped at a statewide scale 50 years ago at a scale of 1:250,000 (Doll and others, 1961). The 1961 map was compiled from 1:62,500-scale...

Bedrock Geologic Map of Vermont - Units

Data.gov (United States)

Vermont Center for Geographic Information — The bedrock geology was last mapped at a statewide scale 50 years ago at a scale of 1:250,000 (Doll and others, 1961). The 1961 map was compiled from 1:62,500-scale...

Mineralogy, geochemistry, porosity and redox properties of rocks from Forsmark. Compilation of data from the regional model volume for SR-Site

Energy Technology Data Exchange (ETDEWEB)

Sandstroem, Bjoern (WSP Sverige AB, Stockholm (Sweden)); Stephens, Michael B. (Geological Survey of Sweden, Uppsala (Sweden))

2009-11-15

This report is a compilation of the data acquired during the Forsmark site investigation programme on the mineralogy, geochemistry, redox properties and porosity of different rock types at Forsmark. The aim is to provide a final summary of the available data for use during the SR-Site modelling work. Data presented in this report represent the regional model volume and have previously been published in various SKB reports. The data have been extracted from the SKB database Sicada and are presented as calculated median values, data range and lower/upper quartile. The representativity of all samples used for the calculations have been evaluated and data from samples where there is insufficient control on the rock type have been omitted. Rock samples affected by alteration have been omitted from the unaltered samples and are presented separately based on type of alteration (e.g. oxidised or albitized rock)

Hydrogeological map of Italy: the preliminary Sheet N. 348 Antrodoco (Central Italy

Directory of Open Access Journals (Sweden)

Marco Amanti

2016-07-01

Full Text Available The Geological Survey of Italy, Italian National Institute for Environmental Protection and Research is realizing the Sheet N.348 Antrodoco (Central Italy of the Hydrogeological map of Italy as a cartographical test of the Italian hydrogeological survey and mapping guidelines, in the frame of the Italian Geological Cartography Project. The study area is characterized by structural units deeply involved in the Apennine Orogeny (Latium and Abruzzi region territory, Rieti and L’Aquila provinces and including deposits of marine carbonate shelf, slope, basin and foredeep environments hosting relatively large amounts of groundwater resources. The map was realized to obtain the best possible representation of all hydrogeological elements deriving from field surveys, in order to characterize the hydrogeological asset. A control network for monthly measurement of surface and groundwater flow rates and hydrogeochemical parameters was performed. Data were uploaded in a geographic information system to perform the present preliminary hydrogeological cartography consisting in a main map showing the following hydrogeological complexes based on relative permeability degree (from bottom to top: i calcareous (Jurassic-Cretaceous; high permeability; ii calcareous-marly (Upper Cretaceous-Middle Eocene; intermediate permeability; iii marly-calcareous and marly (Upper Eocene- Upper Miocene; low permeability; iv flysch (Upper Miocene; low permeability; v conglomeratic-sandy and detritic (Upper Pliocene- Pleistocene; intermediate permeability; vi alluvial (Quaternary; low permeability. Among other elements shown in the main map there are hydrographical basin and sub-basin boundaries, stream gauging stations, meteo-climatic stations, streamwater-groundwater exchange processes, hydrostructure boundaries, point and linear spring flow rates, groundwater flow directions. Furthermore, complementary smaller-scale sketches at the margin of the main map were realized (e

The physical hydrogeology of ore deposits

Science.gov (United States)

Ingebritsen, Steven E.; Appold, M.S.

2012-01-01

Hydrothermal ore deposits represent a convergence of fluid flow, thermal energy, and solute flux that is hydrogeologically unusual. From the hydrogeologic perspective, hydrothermal ore deposition represents a complex coupled-flow problem—sufficiently complex that physically rigorous description of the coupled thermal (T), hydraulic (H), mechanical (M), and chemical (C) processes (THMC modeling) continues to challenge our computational ability. Though research into these coupled behaviors has found only a limited subset to be quantitatively tractable, it has yielded valuable insights into the workings of hydrothermal systems in a wide range of geologic environments including sedimentary, metamorphic, and magmatic. Examples of these insights include the quantification of likely driving mechanisms, rates and paths of fluid flow, ore-mineral precipitation mechanisms, longevity of hydrothermal systems, mechanisms by which hydrothermal fluids acquire their temperature and composition, and the controlling influence of permeability and other rock properties on hydrothermal fluid behavior. In this communication we review some of the fundamental theory needed to characterize the physical hydrogeology of hydrothermal systems and discuss how this theory has been applied in studies of Mississippi Valley-type, tabular uranium, porphyry, epithermal, and mid-ocean ridge ore-forming systems. A key limitation in the computational state-of-the-art is the inability to describe fluid flow and transport fully in the many ore systems that show evidence of repeated shear or tensional failure with associated dynamic variations in permeability. However, we discuss global-scale compilations that suggest some numerical constraints on both mean and dynamically enhanced crustal permeability. Principles of physical hydrogeology can be powerful tools for investigating hydrothermal ore formation and are becoming increasingly accessible with ongoing advances in modeling software.

Hydrogeological flux scenarios at Forsmark. Generic numerical flow simulations and compilation of climatic information for use in the safety analysis SFR1 SAR-08

International Nuclear Information System (INIS)

Vidstrand, Patrik; Naeslund, Jens-Ove; Hartikainen, Juha; Svensson, Urban

2007-11-01

In the earlier modelling for SFR-SAFE it was concluded that the groundwater flow would increase with time along with the shoreline displacement. Even though the numerical results are different the same conclusion is drawn after this study. General conclusions from the present study are that: The upper boundary conditions have a significant impact on the groundwater flow in the geosphere. The characteristic of the surface in regards of being a recharge or discharge area affects the results. In general, a discharge area will experience an increase in groundwater flow under changed conditions. The presence of caging fracture zones affects the results, and, for the tested un-frozen SFR situation, the resulting effect is an increase in groundwater flow. Specific conclusions regarding the relative change of groundwater flow due to different surface conditions are that: The permafrost scenarios, along with the development from sporadic permafrost to continuous permafrost, yield increased groundwater flows in unfrozen parts of the domain. The increase is one order of magnitude or less. In the permafrost, the flow is negligible. The ice sheet scenarios yield situations with significantly increased groundwater flow. The results indicate an increase by two to three orders of magnitude. These increased values, however, apply only for short duration intervals. It is possible that such intervals may be only a couple of years. In the selected climate Base variant, repeating the conditions for the last glacial cycle, permafrost conditions occur after 8,000 years. In the climate variant affected by increased greenhouse warming, permafrost conditions do not occur until after more than 50,000 years. In the chosen climate variants, ice sheets reach the Forsmark area and cause significantly increased groundwater flow, after ∼60,000 years or more

Hydrogeological flux scenarios at Forsmark. Generic numerical flow simulations and compilation of climatic information for use in the safety analysis SFR1 SAR-08

Energy Technology Data Exchange (ETDEWEB)

Vidstrand, Patrik (Bergab, Goeteborg (SE)); Naeslund, Jens-Ove (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Hartikainen, Juha (Helsinki Univ. of Technology, Helsinki (FI)); Svensson, Urban (CFE AB, Karlskrona (SE))

2007-11-15

In the earlier modelling for SFR-SAFE it was concluded that the groundwater flow would increase with time along with the shoreline displacement. Even though the numerical results are different the same conclusion is drawn after this study. General conclusions from the present study are that: The upper boundary conditions have a significant impact on the groundwater flow in the geosphere. The characteristic of the surface in regards of being a recharge or discharge area affects the results. In general, a discharge area will experience an increase in groundwater flow under changed conditions. The presence of caging fracture zones affects the results, and, for the tested un-frozen SFR situation, the resulting effect is an increase in groundwater flow. Specific conclusions regarding the relative change of groundwater flow due to different surface conditions are that: The permafrost scenarios, along with the development from sporadic permafrost to continuous permafrost, yield increased groundwater flows in unfrozen parts of the domain. The increase is one order of magnitude or less. In the permafrost, the flow is negligible. The ice sheet scenarios yield situations with significantly increased groundwater flow. The results indicate an increase by two to three orders of magnitude. These increased values, however, apply only for short duration intervals. It is possible that such intervals may be only a couple of years. In the selected climate Base variant, repeating the conditions for the last glacial cycle, permafrost conditions occur after 8,000 years. In the climate variant affected by increased greenhouse warming, permafrost conditions do not occur until after more than 50,000 years. In the chosen climate variants, ice sheets reach the Forsmark area and cause significantly increased groundwater flow, after approx60,000 years or more

The role of bedrock groundwater in rainfall-runoff response at hillslope and catchment scales

Science.gov (United States)

C. Gabrielli; J.J. McDonnell; W.T. Jarvis

2012-01-01

Bedrock groundwater dynamics in headwater catchments are poorly understood and poorly characterized. Direct hydrometric measurements have been limited due to the logistical challenges associated with drilling through hard rock in steep, remote and often roadless terrain. We used a new portable bedrock drilling system to explore bedrock groundwater dynamics aimed at...

Stochastic hydrogeology: what professionals really need?

Science.gov (United States)

Renard, Philippe

2007-01-01

Quantitative hydrogeology celebrated its 150th anniversary in 2006. Geostatistics is younger but has had a very large impact in hydrogeology. Today, geostatistics is used routinely to interpolate deterministically most of the parameters that are required to analyze a problem or make a quantitative analysis. In a small number of cases, geostatistics is combined with deterministic approaches to forecast uncertainty. At a more academic level, geostatistics is used extensively to study physical processes in heterogeneous aquifers. Yet, there is an important gap between the academic use and the routine applications of geostatistics. The reasons for this gap are diverse. These include aspects related to the hydrogeology consulting market, technical reasons such as the lack of widely available software, but also a number of misconceptions. A change in this situation requires acting at different levels. First, regulators must be convinced of the benefit of using geostatistics. Second, the economic potential of the approach must be emphasized to customers. Third, the relevance of the theories needs to be increased. Last, but not least, software, data sets, and computing infrastructure such as grid computing need to be widely available.

SRP baseline hydrogeologic investigation: Aquifer characterization

Energy Technology Data Exchange (ETDEWEB)

Strom, R.N.; Kaback, D.S.

1992-03-31

An investigation of the mineralogy and chemistry of the principal hydrogeologic units and the geochemistry of the water in the principal aquifers at Savannah River Site (SRS) was undertaken as part of the Baseline Hydrogeologic Investigation. This investigation was conducted to provide background data for future site studies and reports and to provide a site-wide interpretation of the geology and geochemistry of the Coastal Plain Hydrostratigraphic province. Ground water samples were analyzed for major cations and anions, minor and trace elements, gross alpha and beta, tritium, stable isotopes of hydrogen, oxygen, and carbon, and carbon-14. Sediments from the well borings were analyzed for mineralogy and major and minor elements.

Regional hydrogeological conceptual model of candidate Beishan area for high level radioactive waste disposal repository

International Nuclear Information System (INIS)

Wang Hailong; Guo Yonghai

2014-01-01

The numerical modeling of groundwater flow is an important aspect of hydrogeological assessment in siting of a high level radioactive waste disposal repository. Hydrogeological conceptual model is the basic and premise of numerical modeling of groundwater flow. Based on the hydrogeological analysis of candidate Beishan area, surface water system was created by using DEM data and the modeling area is determined. Three-dimensional hydrogeological structure model was created through GMS software. On the basis of analysis and description of boundary condition, flow field, groundwater budget and hydrogeological parameters, hydrogeological conceptual model was set up for the Beishan area. (authors)

Industrial--hydrogeological characteristics of water in the Orenburg Field

Energy Technology Data Exchange (ETDEWEB)

Kortsenshtein, V N; Zhabrev, I P; Uchastkin, Yu V; Alekseeva, I V

1977-06-01

An examination is made of the industrial hydrogeological conditions of the Orenburg Field in connection with the beginning of its development. Features of pay dirt water manifestation are demonstrated, genetic types of water brought out by gas flow are described, and methods are suggested for processing hydrogeological information. 3 references, 2 figures, 1 table.

Hydrogeologic study of Cafam area. Melgar (Tolima)

International Nuclear Information System (INIS)

Angel M, Carlos E; Perez C, Rosalbina

1989-06-01

The hydrogeologic study covers an area of 50 km 2 with the objectives of to determine the possibility of use of the underground waters and to locate places to carry out exploratory perforations in lands of Cafam, equally the elaboration of a hydrogeologic map of the region; for the effect it was carried out cartography geologic scale 1:10.000, inventory and sampling of water point, geoelectric prospecting and some permeability tests. In the area the exploitation of underground water is incipient, alone there are 20 points of water, of which none produce more than 1L/seg. The water has in general good physical chemistry quality for the human consumption. Geologically was recognized the groups Guadalupe and Gualanday, also some quaternary deposits; the previous ones were subdivided in 11 geological units for its composition and morphology, which are framed structurally in the E flank of the synclinal of Carmen de Apicala and displaced by traverse faults with address E-W and N-W. From the point of hydrogeologic view the units were grouped in 8 aquifer systems, of which four are considered of hydrogeologic importance for the area; the sector with better possibilities to capture these aquifer systems is the W of the area (in the terraces area) that extends to the Sumapaz River. For the Cafam sector a place was selected to build an exploratory well of 200 mts. of depth that would capture an aquifer of low transmissivity, corresponding to the Unit T3

Numerical simulation of ground-water flow through glacial deposits and crystalline bedrock in the Mirror Lake area, Grafton County, New Hampshire

Science.gov (United States)

Tiedeman, Claire; Goode, Daniel J.; Hsieh, Paul A.

1997-01-01

This report documents the development of a computer model to simulate steady-state (long-term average) flow of ground water in the vicinity of Mirror Lake, which lies at the eastern end of the Hubbard Brook valley in central New Hampshire. The 10-km2 study area includes Mirror Lake, the three streams that flow into Mirror Lake, Leeman's Brook, Paradise Brook, and parts of Hubbard Brook and the Pemigewasset River. The topography of the area is characterized by steep hillsides and relatively flat valleys. Major hydrogeologic units include glacial deposits, composed of till containing pockets of sand and gravel, and fractured crystalline bedrock, composed of schist intruded by granite, pegmatite, and lamprophyre. Ground water occurs in both the glacial deposits and bedrock. Precipitation and snowmelt infiltrate to the water table on the hillsides, flow downslope through the saturated glacial deposits and fractured bedrock, and discharge to streams and to Mirror Lake. The model domain includes the glacial deposits, the uppermost 150m of bedrock, Mirror Lake, the layer of organic sediments on the lake bottom, and streams and rivers within the study area. A streamflow routing package was included in the model to simulate baseflow in streams and interaction between streams and ground water. Recharge from precipitation is assumed to be areally uniform, and riparian evapotranspiration along stream banks is assumed negligible. The spatial distribution of hydraulic conductivity is represented by dividing the model domain into several zones, each having uniform hydraulic properties. Local variations in recharge and hydraulic conductivities are ignored; therefore, the simulation results characterize the general ground-water system, not local details of ground-water movement. The model was calibrated using a nonlinear regression method to match hydraulic heads measured in piezometers and wells, and baseflow in three inlet streams to Mirror Lake. Model calibration indicates that

Identification Of Rippability And Bedrock Depth Using Seismic Refraction

Science.gov (United States)

Ismail, Nur Azwin; Saad, Rosli; Nawawi, M. N. M.; Muztaza, Nordiana Mohd; El Hidayah Ismail, Noer; Mohamad, Edy Tonizam

2010-12-01

Spatial variability of the bedrock with reference to the ground surface is vital for many applications in geotechnical engineering to decide the type of foundation of a structure. A study was done within the development area of Mutiara Damansara utilising the seismic refraction method using ABEM MK8 24 channel seismograph. The geological features of the subsurface were investigated and velocities, depth to the underlying layers were determined. The seismic velocities were correlated with rippability characteristics and borehole records. Seismic sections generally show a three layer case. The first layer with velocity 400-600 m/s predominantly consists of soil mix with gravel. The second layer with velocity 1600-2000 m/s is suggested to be saturated and weathered area. Both layers forms an overburden and generally rippable. The third layer represents granite bedrock with average depth and velocity 10-30 m and >3000 m/s respectively and it is non-rippable. Steep slope on the bedrock are probably the results of shear zones.

Identification Of Rippability And Bedrock Depth Using Seismic Refraction

International Nuclear Information System (INIS)

Ismail, Nur Azwin; Saad, Rosli; Nawawi, M. N. M; Muztaza, Nordiana Mohd; El Hidayah Ismail, Noer; Mohamad, Edy Tonizam

2010-01-01

Spatial variability of the bedrock with reference to the ground surface is vital for many applications in geotechnical engineering to decide the type of foundation of a structure. A study was done within the development area of Mutiara Damansara utilising the seismic refraction method using ABEM MK8 24 channel seismograph. The geological features of the subsurface were investigated and velocities, depth to the underlying layers were determined. The seismic velocities were correlated with rippability characteristics and borehole records. Seismic sections generally show a three layer case. The first layer with velocity 400-600 m/s predominantly consists of soil mix with gravel. The second layer with velocity 1600-2000 m/s is suggested to be saturated and weathered area. Both layers forms an overburden and generally rippable. The third layer represents granite bedrock with average depth and velocity 10-30 m and >3000 m/s respectively and it is non-rippable. Steep slope on the bedrock are probably the results of shear zones.

Socio-hydrogeology and low-income countries: taking science to rural society

Science.gov (United States)

Limaye, Shrikant Daji

2017-11-01

Rural societies in low-income, high-population countries often faces scarcity of water of suitable quality for domestic use and agriculture. Hydrogeologists should therefore orientate their research work towards solving practical problems and impart basic knowledge about the hydrogeology of local watersheds to the village councils and communities so as to ensure their participation in better management of groundwater resources. Such cooperation between the hydrogeologists and villagers is the foundation of socio-hydrogeology, which aims at broader dissemination of information and discussions with hydrogeologists at village meetings regarding watershed management such as recharge augmentation, groundwater quality issues and prudent use of groundwater. Socio-hydrogeology implies improved accessibility of rural society to hydrogeological experts and better communication through the use of more appropriate and understandable language.

Advanced on-site conceptual simulator for Forsmark 3

International Nuclear Information System (INIS)

Johansson, G.; Sjoestrand, K.

1984-01-01

On-site conceptual simulators have been extensively used at Swedish nuclear power plants. Despite having access to identical replica simulators, both the Swedish State Power Board and the Swedish private power industry have ordered conceptual simulators during 1982. The motivation has been that a complete training programme requires access to both a replica and a conceptual simulator. The replica simulator is perfect for training in control room behaviour but less appropriate for ensuring deeper process understanding. On the other hand, the conceptual simulator is not well suited for getting the personnel acquainted with the control room but is perfect for extending their knowledge of the plant processes. In order to give a realistic description of these processes, the conceptual simulator model must be fairly advanced. The Forsmark 3 conceptual simulator simulates the entire primary system, including the details of the steam and feedwater systems. Considerable attention has also been devoted to the presentation of calculated variables. For example, all the variables in the data base (approx. 6600) can be presented on colour-graphic CRTs as functions of time. (author)

Forsmark site characterisation - Borehole KFM22 and KFM23: Derivation of porewater data by diffusion experiments

Energy Technology Data Exchange (ETDEWEB)

Waber, H. N. [Rock Water Interaction, University of Bern, Bern (Switzerland); Smellie, J. A. T. [Conterra AB, Partille (Sweden)

2012-04-15

Within the Detum Project (Detailed Investigations in Forsmark) a 'Methodology comparison for porewater extraction and characterisation techniques' was initiated. This has centred on two shallow boreholes drilled at Soederviken within the northern part of the Forsmark characterisation site. The comparison includes different methodologies to characterise the chemical and isotopic composition of porewater residing in the connected pore space of the rock matrix. The present report describes the chemical and isotopic information of the porewater obtained by out-diffusion experiments and the diffusive isotope equilibration technique applied to originally water saturated drillcore samples. In addition, petrophysical data and solute transport properties of the rock matrix, all necessary for porewater characterisation, have also been elaborated. Specially conditioned drillcore samples were obtained from depths of less than 100 m from boreholes KFM22 and KFM23. Porewater has been extracted successfully from seven samples by laboratory out-diffusion and diffusive isotope exchange methods. The methodology to extract and analyse the porewater is outlined and the analytical data are tabulated. The data are critically reviewed for potential experimental artefacts and their significance with respect to in situ conditions. The connected pore space in the core material representing borehole KFM22 and KFM23 was measured on different types of originally saturated drillcore samples using gravimetric and isotope mass balance methods. Out-diffusion experiments were performed on kg-sized drillcore samples to derive the in situ concentration of the chemically conservative compounds chloride and bromide. The attainment of equilibrium conditions in the out-diffusion experiments was monitored by the concentration change of chloride and bromide as a function of time. The water isotope composition of porewater was determined by the diffusive isotope equilibration technique and by

BWR-stability investigation at Forsmark 1

International Nuclear Information System (INIS)

Bergdahl, B.G.; Reisch, F.; Oguma, R.; Lorenzen, J.; Aakerhielm, F.

1988-01-01

A series of noise measurements have been conducted at Forsmark 1 during start-up operation after the revision summer '87. The main purpose was to investigate BWR-stability problems, i.e. resonant power oscillations of 0.5 Hz around 65% power and 4100 kg/s core flow, which tend to arise at high power and low core flow conditions. The analysis was performed to estimate the noise source which gives rise to the oscillation, to evaluate the measure of stability, i.e. the Decay Ratio (Dr) as well as to investigate other safety related problems. The result indicates that the oscillation is due to the dynamic coupling between the neutron kinetics and thermal hydraulics via void reactivity feedback. The Dr ranged between values of 0.7 and > 0.9, instead of expected 0.6 (Dr=1 is defined as instability). These high values imply that the core cannot suppress oscillations fast enough and a small perturbation can cause scram. Further it was found that the entire core is oscillating in phase (LPRM's) with varying strength where any connection to the consequences of different fuel (8x8, 9x9) being present simultaneously cannot be excluded. This report elucidates the importance of an on-line BWR-stability surveillance system with functions like stability condition monitoring and control system diagnosis. (orig.)

Hydrogeology of Rome

Directory of Open Access Journals (Sweden)

Roberto Mazza

2015-12-01

Full Text Available In this paper the hydrogeological setting of Rome is figured out. This setting has been strongly influenced by different factors as tectonic activity, volcanism and seal level variations. The conceptual model of the groundwater flow in the roman area is represented by four aquifers, three of which being overlappingones. These aquifers flow from peripheral sectors of the study area toward Tiber and Aniene Rivers and the Sea.

Characterization of humic substances from deep groundwaters in granitic bedrock in Sweden

International Nuclear Information System (INIS)

Pettersson, C.; Ephraim, J.; Allard, B.; Boren, H.

1990-06-01

Humic substances were isolated from deep groundwaters sampled at depths between 100 and 800 m at Finnsjoen, Fjaellveden, Forsmark, Gidea, Lansjaerv, Stripa and Aespoe. The humic fraction, which largely consisted of fulvic acid in all the samples, was characterized with respect to elemental composition, molecular weight, acid capacity (COOH and OH) as well as age ( 14 C). The differences in composition and capacity between old (1270-9675 y) and fresh (reference fulvic acid from surface water, Bersbo) were minor. (orig.)

HYDROGEOLOGIC CASE STUDIES (DENVER PRESENTATION)

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

HYDROGEOLOGIC CASE STUDIES (CHICAGO, IL)

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

Hydrogeologic Case Studies (Seattle, WA)

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

Contaminant Hydrogeology, 2nd Edition

Science.gov (United States)

Smith, James E.

Groundwater is a valuable resource that has received much attention over the last couple of decades. Extremely large sums of money have been and will be spent on groundwater contamination problems and the public has become increasingly sensitive to groundwater issues. Groundwater contamination has even become the subject of a major Hollywood movie with the recent release of A Civil Action starring John Travolta. The high profile of groundwater contaminant problems, the associated relatively strong job market over the last 20 years, and the general shift toward an environmental emphasis in science and engineering have resulted in a sustained high demand for senior undergraduate courses and graduate programs in hydrogeology Many voice the opinion that we have seen the peak demand for hydrogeologists pass, but the placement of graduates from hydrogeology programs into career-oriented positions has remained very high.

Depth to Bedrock: Isopach of Unconsolidated Materials

Data.gov (United States)

Iowa State University GIS Support and Research Facility — This vector dataset gives the approximate depth to bedrock (in feet) from Iowa's current land surface. This 50 foot isopach data was derived from the Digital...

Permafrost delineation for remediation planning : Fort Wainwright, Alaska

Energy Technology Data Exchange (ETDEWEB)

Astley, B. [Cold Regions Research and Engineering Laboratory, Anchorage, AK (United States); Snyder, C. [YEC Inc., Valley Cottage, NJ (United States); Delaney, A. [Cold Regions Research and Engineering Laboratory, Fairbanks, AK (United States); Arcone, S.; Lawson, D. [Cold Regions Research and Engineering Laboratory, Hanover, NH (United States)

2003-07-01

In the summer of 1999, geophysical and hydrogeological surveys were conducted at the Birch Hill Tank Farm and Truck Fill Stand in Fort Wainwright, Alaska to assess the distribution of benzene, 1,2-dichloroethane, and 1,2-dibromoethane. The Birch Hill site consists of a silt, sand and gravel fluvial deposit that overlies bedrock. Permafrost occurs discontinuously throughout the alluvium and underlying bedrock, resulting in a complex aquifer distribution. The bedrock beneath the Tank Farm is highly fractured and faulted with a weathered horizon that is 30 meters thick. The goal of this study was to map the discontinuous permafrost and aquifers in the alluvial deposits and weathered bedrock zone for the purpose of delineating bedrock depth and structural features that influence ground water flow. Several methods were used to define subsurface conditions, including borehole logs, DC resistivity, and ground-penetrating radar. A 3-D hydrogeologic model was used to develop a ground water flow model used to determine contaminant migration pathways and rates. The permafrost configuration was found to be the most important boundary condition in this model. 7 refs., 1 tab., 5 figs.

[Effect of irregular bedrock topography on the soil profile pattern of water content in a Karst hillslope.

Science.gov (United States)

Jia, Jin Tian; Fu, Zhi Yong; Chen, Hong Song; Wang, Ke Lin; Zhou, Wei Jun

2016-06-01

Based on three manually excavated trenches (projection length of 21 m, width of 1 m) along a typical Karst hillslope, the changing trends for soil-bedrock structure, average water content of soil profile and soil-bedrock interface water content along each individual trench were studied. The effect of irregular bedrock topography on soil moisture distribution was discussed. The results showed that the surface topography was inconsistent with the bedrock topography in the Karst hill-slopes. The bedrock topography was highly irregular with a maximum variation coefficient of 82%. The distribution pattern of soil profile of moisture was significantly affected by the underlying undulant bedrock. The soil water content was related to slope position when the fluctuation was gentle, and displayed a linear increase from upslope to downslope. When the bedrock fluctuation increased, the downslope linear increasing trend for soil water content became unapparent, and the spatial continuity of soil moisture was weakened. The soil moisture was converged in rock dents and cracks. The average water content of soil profile was significantly positively correlated with the soil-bedrock interface water content, while the latter responded more sensitively to the bedrock fluctuation.

Bedrock erosion by sliding wear in channelized granular flow

Science.gov (United States)

Hung, C. Y.; Stark, C. P.; Capart, H.; Smith, B.; Maia, H. T.; Li, L.; Reitz, M. D.

2014-12-01

Boundary forces generated by debris flows can be powerful enough to erode bedrock and cause considerable damage to infrastructure during runout. Bedrock wear can be separated into impact and sliding wear processes. Here we focus on sliding wear. We have conducted experiments with a 40-cm-diameter grainflow-generating rotating drum designed to simulate dry channelized debris flows. To generate sliding erosion, we placed a 20-cm-diameter bedrock plate axially on the back wall of the drum. The rotating drum was half filled with 2.3-mm-diameter grains, which formed a thin grain-avalanching layer with peak flow speed and depth close to the drum axis. The whole experimental apparatus was placed on a 100g-ton geotechnical centrifuge and, in order to scale up the stress level, spun to a range of effective gravity levels. Rates and patterns of erosion of the bedrock plate were mapped after each experiment using 3d micro-photogrammetry. High-speed video and particle tracking were employed to measure granular flow dynamics. The resulting data for granular velocities and flow geometry were used to estimate impulse exchanges and forces on the bedrock plate. To address some of the complexities of granular flow under variable gravity levels, we developed a continuum model framed around a GDR MiDi rheology. This model allowed us to scale up boundary forcing while maintaining the same granular flow regime, and helped us to understand important aspects of the flow dynamics including e.g. fluxes of momentum and kinetic energy. In order to understand the detailed processes of boundary forcing, we performed numerical simulations with a new contact dynamics model. This model confirmed key aspects of our continuum model and provided information on second-order behavior such as fluctuations in the forces acting on the wall. By combining these measurements and theoretical analyses, we have developed and calibrated a constitutive model for sliding wear that is a threshold function of

Hydrogeological characterization of deep subsurface structures at the Mizunami Underground Research Laboratory

International Nuclear Information System (INIS)

Takeuchi, Shinji; Saegusa, Hiromitsu; Amano, Kenji; Takeuchi, Ryuji

2013-01-01

Several hydrogeological investigation techniques have been used at the Mizunami Underground Research Laboratory site to assess hydrogeological structures and their control on groundwater flow. For example, the properties of water-conducting features (WCFs) can be determined using high-resolution electrical conductivity measurements of fluids, and compared to measurements using conventional logging techniques. Connectivity of WCFs can be estimated from transmissivity changes over time, calculated from the pressure derivative of hydraulic pressure data obtained from hydraulic testing results. Hydraulic diffusivity, obtained from hydraulic interference testing by considering the flow dimension, could be a key indicator of the connectivity of WCFs between boreholes. A conceptual hydrogeological model of several hundred square meters to several square kilometers, bounded by flow barrier structures, has been developed from pressure response plots, based on interference hydraulic testing. The applicability of several methods for developing conceptual hydrogeological models has been confirmed on the basis of the hydrogeological investigation techniques mentioned above. (author)

Bedrock Geologic Map of Charlotte,�Vermont

Data.gov (United States)

Vermont Center for Geographic Information — Digital Data from VG09-5 Gale, M., Kim, J., Earle, H., Clark, A., Smith, T., and Petersen, K., 2009, Bedrock Geologic Map of Charlotte, Vermont: VGS Open-File Report...

Groundwater availability as constrained by hydrogeology and environmental flows.

Science.gov (United States)

Watson, Katelyn A; Mayer, Alex S; Reeves, Howard W

2014-01-01

Groundwater pumping from aquifers in hydraulic connection with nearby streams has the potential to cause adverse impacts by decreasing flows to levels below those necessary to maintain aquatic ecosystems. The recent passage of the Great Lakes-St. Lawrence River Basin Water Resources Compact has brought attention to this issue in the Great Lakes region. In particular, the legislation requires the Great Lakes states to enact measures for limiting water withdrawals that can cause adverse ecosystem impacts. This study explores how both hydrogeologic and environmental flow limitations may constrain groundwater availability in the Great Lakes Basin. A methodology for calculating maximum allowable pumping rates is presented. Groundwater availability across the basin may be constrained by a combination of hydrogeologic yield and environmental flow limitations varying over both local and regional scales. The results are sensitive to factors such as pumping time, regional and local hydrogeology, streambed conductance, and streamflow depletion limits. Understanding how these restrictions constrain groundwater usage and which hydrogeologic characteristics and spatial variables have the most influence on potential streamflow depletions has important water resources policy and management implications. © 2013, National Ground Water Association.

Bedrock K{sub d} data and uncertainty assessment for application in SR-Site geosphere transport calculations

Energy Technology Data Exchange (ETDEWEB)

Crawford, James (Kemakta Konsult AB, Stockholm (Sweden))

2010-12-15

The safety assessment SR-Site is undertaken to assess the safety of a potential geologic repository for spent nuclear fuel at the Forsmark and Laxemar sites. The present report is one of several reports that form the data input to SR-Site and contains a compilation of recommended K{sub d} data (i.e. linear partitioning coefficients) for safety assessment modelling of geosphere radionuclide transport. The data are derived for rock types and groundwater compositions distinctive of the site investigation areas at Forsmark and Laxemar. Data have been derived for all elements and redox states considered of importance for far-field dose estimates as described in /SKB 2010d/. The K{sub d} data are given in the form of lognormal distributions characterised by a mean (mu) and standard deviation (sigma). Upper and lower limits for the uncertainty range of the recommended data are defined by the 2.5% and 97.5% percentiles of the empirical data sets. The best estimate K{sub d} value for use in deterministic calculations is given as the median of the K{sub d} distribution

Developing and exploring a theory for the lateral erosion of bedrock channels for use in landscape evolution models

Directory of Open Access Journals (Sweden)

A. L. Langston

2018-01-01

Full Text Available Understanding how a bedrock river erodes its banks laterally is a frontier in geomorphology. Theories for the vertical incision of bedrock channels are widely implemented in the current generation of landscape evolution models. However, in general existing models do not seek to implement the lateral migration of bedrock channel walls. This is problematic, as modeling geomorphic processes such as terrace formation and hillslope–channel coupling depends on the accurate simulation of valley widening. We have developed and implemented a theory for the lateral migration of bedrock channel walls in a catchment-scale landscape evolution model. Two model formulations are presented, one representing the slow process of widening a bedrock canyon and the other representing undercutting, slumping, and rapid downstream sediment transport that occurs in softer bedrock. Model experiments were run with a range of values for bedrock erodibility and tendency towards transport- or detachment-limited behavior and varying magnitudes of sediment flux and water discharge in order to determine the role that each plays in the development of wide bedrock valleys. The results show that this simple, physics-based theory for the lateral erosion of bedrock channels produces bedrock valleys that are many times wider than the grid discretization scale. This theory for the lateral erosion of bedrock channel walls and the numerical implementation of the theory in a catchment-scale landscape evolution model is a significant first step towards understanding the factors that control the rates and spatial extent of wide bedrock valleys.

Developing and exploring a theory for the lateral erosion of bedrock channels for use in landscape evolution models

Science.gov (United States)

Langston, Abigail L.; Tucker, Gregory E.

2018-01-01

Understanding how a bedrock river erodes its banks laterally is a frontier in geomorphology. Theories for the vertical incision of bedrock channels are widely implemented in the current generation of landscape evolution models. However, in general existing models do not seek to implement the lateral migration of bedrock channel walls. This is problematic, as modeling geomorphic processes such as terrace formation and hillslope-channel coupling depends on the accurate simulation of valley widening. We have developed and implemented a theory for the lateral migration of bedrock channel walls in a catchment-scale landscape evolution model. Two model formulations are presented, one representing the slow process of widening a bedrock canyon and the other representing undercutting, slumping, and rapid downstream sediment transport that occurs in softer bedrock. Model experiments were run with a range of values for bedrock erodibility and tendency towards transport- or detachment-limited behavior and varying magnitudes of sediment flux and water discharge in order to determine the role that each plays in the development of wide bedrock valleys. The results show that this simple, physics-based theory for the lateral erosion of bedrock channels produces bedrock valleys that are many times wider than the grid discretization scale. This theory for the lateral erosion of bedrock channel walls and the numerical implementation of the theory in a catchment-scale landscape evolution model is a significant first step towards understanding the factors that control the rates and spatial extent of wide bedrock valleys.

Preliminary Bedrock Geologic Map of the Old Lyme Quadrangle, New London and Middlesex Counties, Connecticut

Science.gov (United States)

Walsh, Gregory J.; Scott, Robert B.; Aleinikoff, John N.; Armstrong, Thomas R.

2006-01-01

This report presents a preliminary map of the bedrock geology of the Old Lyme quadrangle, New London and Middlesex Counties, Connecticut. The map depicts contacts of bedrock geologic units, faults, outcrops, and structural geologic information. The map was published as part of a study of fractured bedrock aquifers and regional tectonics.

Hydrogeology of exogenic epigenic uranium deposits (sedimentary type) in Uzbekistan

International Nuclear Information System (INIS)

Irgashev, Yu.I.; Gavrilov, V.A.; Muslimov, B.A.

1996-01-01

Common problems of hydrogeology and geotechnology for uranium deposits (sedimentary type) in the Republic of Uzbekistan are discussed in the paper. Hydrogeology includes studies of texture of water-bearing horizons, occurrences of ore bodies in horizons, hydrochemical survey, hydrodynamics and engineering geology. Features of deposits workable by underground leaching are presented. Such terms as 'water-bearing horizon', 'efficiency', 'water-bearing bed' are explained accounting the results of 30 year investigations conducted during prospecting, designing and exploitation of uranium deposits. Stages of hydrogeological survey are listed and features of each of them are described. Importance of geotechnology for a deposit characterization is shown. (author). 6 refs.; 1 fig.; 1 tab

BIM som Informationsbärare in i Förvaltningen : En studie vid Forsmarks Kraftgrupp

OpenAIRE

Svens, Therése

2013-01-01

BIM, Building Information Modeling, börjar vinna mark inom byggbranschen i Sverige och är en vedertagen process i vart och vartannat byggprojekt. Forsmarks Kraftgrupp står inför både upprustningar av sina anläggningar och nyproduktion av bland annat kontor, verkstad och hotell. BIM framstår nu som en lukrativ metod för att dra ner på projektkostnaderna, men även för att få ytterligare ordning och struktur på den enorma mängd dokumentation som ackumulerat under de dryga trettio åren av drift. ...

The origin and significance of sinuosity along incising bedrock rivers

Science.gov (United States)

Barbour, Jonathan Ross

Landscapes evolve through processes acting at the earth's surface in response to tectonics and climate. Rivers that cut into bedrock are particularly important since they set the local baselevel and communicate changes in boundary conditions across the landscape through erosion and deposition; the pace of topographic evolution depends on both the rate of change of the boundary conditions and the speed of the bedrock channel network response. Much of the work so far has considered the effects of tectonically-controlled changes in slope and climatically-controlled changes in discharges to the rate of channel bed erosion while considering bank erosion, if active at all, to be of at best secondary importance to landscape evolution. Sprinkled throughout the literature of the past century are studies that have recognized lateral activity along incising rivers, but conflicting interpretations have left many unanswered questions about how to identify and measure horizontal erosion, what drives it, what effect it has on the landscape, and how it responds to climate and tectonics. In this thesis, I begin to answer some of these questions by focusing on bedrock river sinuosity and its evolution through horizontal erosion of the channel banks. An analysis of synoptic scale topography and climatology of the islands of eastern Asia reveals a quantitative signature of storm frequency in a regional measure of mountain river sinuosity. This is partly explained through a study of the hydro- and morphodynamics of a rapidly evolving bedrock river in Taiwan which shows how the erosive forces vary along a river to influence the spatiotemporal distribution of downcutting, sidecutting, and sediment transport. Through these analyses, I also present evidence that suggests that the relative frequency of erosive events is far more important than the absolute magnitude of extreme events in setting the erosion rate, and I show that the horizontal erosion of bedrock rivers is an important

Ground source energy in crystalline bedrock - increased energy extraction by using hydraulic fracturing in boreholes

Energy Technology Data Exchange (ETDEWEB)

Ramstad, Randi Kalstad

2004-11-01

The use of improved equipment and methodology can result in considerable reductions in the drilling costs for medium- to large sized ground source heat pump system in crystalline bedrock. The main point has been to use special techniques within hydraulic fracturing to create a larger heat exchange area in the bedrock, and thus a greater energy extraction per borehole. The energy extraction is based on circulating groundwater. Stimulation with hydraulic fracturing is a well known technique in order to improve borehole yields for drinking water-, oil-, and geothermal purposes. A procedure for injection of propping agents in selected borehole sections, and custom-made equipment for hydraulic fracturing in crystalline bedrock, a double packer, have been developed in this study. The propping agents are likely to ensure a permanent improvement of the hydraulic conductivity in a long-run perspective. In addition to a pre-test, a comprehensive test programme has been performed at each of the two pilot plants at Bryn and at the former property of Energiselskapet Asker og Baerum (EAB) in Baerum municipality outside Oslo, Norway. A total of 125 stimulations with hydraulic fracturing using water-only and hydraulic fracturing with injection of sand have been performed in 9 boreholes. Test pumping and geophysical logging (temperature, electrical conductivity, gamma radiation, optical televiewer and flow measurements) have been carried out in order to document the effect of the hydraulic fracturing. The pilot plants at Bryn and EAB, where the ground source heat pump systems are based on circulating groundwater, have demonstrated the short-period energy extraction, limitations and opportunities of the concept for hydraulic fracturing and increased energy extraction in different geological and hydrogeological areas. The bedrock at Bryn and EAB is characterized as a low-metamorphic sandstone and a nodular limestone, respectively. At Bryn, the five boreholes were organised with a

Hydrogeological Investigation and Groundwater Potential ...

African Journals Online (AJOL)

The paper assesses groundwater quality and productivity in Haromaya watershed, eastern. Ethiopia. ... zones, quantity and quality of plant and animal life (Tamire H., 1981). Steep to very ... Present research work was proposed to conduct hydrogeological investigation and assess ...... Water Balance of Haromaya basin,.

Chemistry data from surface ecosystems in Forsmark and Laxemar-Simpevarp. Site specific data used for estimation of CR and Kd values in SR-Site

International Nuclear Information System (INIS)

Troejbom, Mats; Norden, Sara

2010-11-01

This report is a background report for the biosphere analysis of the SR-Site Safety Assessment. This work aims to compile information from the Forsmark and Laxemar-Simpevarp sites in order to select and provide relevant site data for parameter sed in the Radionuclide Dose Model. This report contains an overview of all available chemistry data from the surface ecosystems at Forsmark and Laxemar-Simpevarp areas, comprising hydrochemistry of shallow groundwater, porewater, lake water, stream water and sea water as well as the chemical composition of the regolith and biota of the terrestrial, limnic and marine ecosystems. Detailed references to data reports are tabulated and all sampling points are shown in a large number of maps in Chapter 2. An explorative analysis in Chapter 3 is the basis for the final selection of site data described in Chapter 4

Detections of MTBE in surficial and bedrock aquifers in New England

International Nuclear Information System (INIS)

Grady, S.J.

1995-01-01

The gasoline additive methyl tert-butyl ether (MTBE) was detected in 24% of water samples collected from surficial and bedrock aquifers in areas of New England. MTBE was the most frequently detected volatile organic compound among the 60 volatile chemicals analyzed and was present in 33 of 133 wells sampled from July 1993 through September 1995. The median MTBE concentration measured in ground-water samples was 0.45 microgram per liter and concentrations ranged from 0.2 to 5.8 microgram per liter. The network of wells sampled for MTBE consisted of 103 monitoring wells screened in surficial sand-and-gravel aquifers and 30 domestic-supply wells in fractured crystalline bedrock aquifers. Seventy-seven percent of all MTBE detections were from 26 shallow monitoring wells screened in surficial aquifers. MTBE was detected in42% of monitoring wells in urban areas. In agricultural areas, MTBE was detected i 8% (2 of 24) of wells and was not detected in undeveloped areas. Sixty-two percent of the MTBE detections in surficial aquifers were from wells within 0.25 mile of gasoline stations or underground gasoline storage tanks; all but one of these wells were in Connecticut and Massachusetts, where reformulated gasoline is used. MTBE was detected in 23% of deep domestic-supply wells that tapped fractured bedrock aquifers. MTBE was detected in bedrock wells only in Connecticut and Massachusetts; land use near the wells was suburban to rural, and none of the sampled bedrock wells were within 0.25 mile of a gasoline station

Hydro-geophysical investigations for groundwater at Atan ...

African Journals Online (AJOL)

The depth to bedrock varies from 5.5 - 53.1m with resistivity values ranging between 61 -11,292 ohm-m. The hydro-geologic study focused on measurement of depth to water table and actual depth of the hand dug wells while the geological aspect of the work was hinged on a geologic mapping. The results of hydrogeologic ...

Organizational development at Forsmark NPP

International Nuclear Information System (INIS)

Metzen, H.

2001-01-01

Forsmark is a three unit BWR site with a total capacity of 3200 MW. Units 1 and two are identical and went into commercial operation in 1980 and 1981. Unit 3 is of a later design with an output of 1200 MW and has been operating since 1985. The average availability for the site has been over 90% for the last 10 years, and the total busbar cost has been competitive. A consistent management strategy has been used to achieve the good results. Several organizational modifications have been made during the years to adapt the organization to changing internal and external conditions. An overall goal regarding staffing has been to keep the number of employees at the same level as in 1985 when Unit 3 went into commercial operation. During the time period from 1975, when the operational organization was formed, until today, the focus for the organization has changed several times. During the commissioning period the focus was on training and establishing routines and procedures. During the first years of operation development of maintenance programs and taking over activities from the supplier dominated. Next area in focus was increasing availability and making the outages more efficient. Several minor modifications to the plant were made to support maintenance activities. More focus on cost reduction and increasing the production through technical modifications were next. After 15 years of operation the need for replacement of components to ensure reliable operation was evident. A program for major modifications was developed, aiming at 40 years lifetime. Deregulation of the Nordic Electricity Market now calls for further reductions in production costs. (author)

Bedrock Model of the Syyry area

International Nuclear Information System (INIS)

Saksa, P.; Kuivamaeki, A.; Kurimo, M.; Paananen, M.; Anttila, P.; Front, K.; Pitkaenen, P.; Hassinen, P.; Ylinen, A.

1993-09-01

Preliminary site investigations implemented in accordance with the research programme drawn up by Teollisuuden Voima Oy (TVO) were carried out at Syyry (in Finland) in 1987-1992. Models of the site were compiled and used for describing the rock types, fracturing, fracture structures and geohydrological conditions, the main emphasis being on the examination of the bedrock fracturing and related hydraulic conductivity. Three-dimensional models were used for the classification of the various properties of the bedrock structures. The descriptive models were gathered into a computer system to facilitate illustration and storage. The main rock type at Syyry is tonalite. A mica gneiss formation SE of the investigation site dips towards the NW and delimits the tonalite as far as the central part of the investigation site. The miga gneiss has a heterogeneous composition and includes intermediate layers consisting of quartz feldspar schist and amphibolite. There are mafic formations in the vicinity of the investigation site. The intrusive rocks have been deformed during three plastic and three mainly brittle deformation stages. (47 refs., 61 figs.)

Forsmark site investigation. Hydrochemical investigations in four calciferous lakes in the Forsmark area. Results from the second year of a complementary investigation in the Forsmark area

International Nuclear Information System (INIS)

Qvarfordt, Susanne; Borgiel, Micke; Berg, Cecilia

2011-12-01

The present report documents the results from the second year of hydrochemical investigations in four small, calciferous lakes in the Forsmark area in order to study the lake water compositions. The construction of a permanent storage facility for used nuclear fuel may result in a lowering of the ground water level and also lake surface water levels. Restoration of habitats by adding water may be an option to reduce possible negative consequences induced by a lower water level on biodiversity and valuable species. Thus, knowledge of the water composition is needed. This report presents the results from six sampling occasions during January to December 2010. The results from the sampling of the four lakes includes field measurements of redox potential (ORP), pH, dissolved oxygen, electrical conductivity, salinity, depth, atmospheric pressure, turbidity, chlorophyll and water temperature, as well as chemical analyses of major constituents and nutrient salts. The four investigated small lakes are well buffered with high alkalinity, high pH and high calcium concentrations. This is in accordance with results from the ongoing monitoring programme of lakes and streams in the area and with the results from the previous sampling period (2008-2009). The results show both seasonal and inter-annual variation in the analysed parameters. This can be explained by seasonal changes and annual differences in temperature, ice-cover, precipitation etc and lake specific parameters such as lake size and drainage area. The variation highlights the importance of both year round sampling and continued sampling for several years when discussing the water composition

Forsmark site investigation. Hydrochemical investigations in four calciferous lakes in the Forsmark area. Results from the second year of a complementary investigation in the Forsmark area

Energy Technology Data Exchange (ETDEWEB)

Qvarfordt, Susanne; Borgiel, Micke [Sveriges Vattenekologer AB, Vingaaker (Sweden); Berg, Cecilia [Geosigma AB, Uppsala (Sweden)

2011-12-15

The present report documents the results from the second year of hydrochemical investigations in four small, calciferous lakes in the Forsmark area in order to study the lake water compositions. The construction of a permanent storage facility for used nuclear fuel may result in a lowering of the ground water level and also lake surface water levels. Restoration of habitats by adding water may be an option to reduce possible negative consequences induced by a lower water level on biodiversity and valuable species. Thus, knowledge of the water composition is needed. This report presents the results from six sampling occasions during January to December 2010. The results from the sampling of the four lakes includes field measurements of redox potential (ORP), pH, dissolved oxygen, electrical conductivity, salinity, depth, atmospheric pressure, turbidity, chlorophyll and water temperature, as well as chemical analyses of major constituents and nutrient salts. The four investigated small lakes are well buffered with high alkalinity, high pH and high calcium concentrations. This is in accordance with results from the ongoing monitoring programme of lakes and streams in the area and with the results from the previous sampling period (2008-2009). The results show both seasonal and inter-annual variation in the analysed parameters. This can be explained by seasonal changes and annual differences in temperature, ice-cover, precipitation etc and lake specific parameters such as lake size and drainage area. The variation highlights the importance of both year round sampling and continued sampling for several years when discussing the water composition.

West Siberian basin hydrogeology - regional framework for contaminant migration from injected wastes

International Nuclear Information System (INIS)

Foley, M.G.

1994-05-01

Nuclear fuel cycle activities of the former Soviet Union (FSU) have resulted in massive contamination of the environment in western Siberia. We are developing three-dimensional numerical models of the hydrogeology and potential contaminant migration in the West Siberian Basin. Our long-term goal at Pacific Northwest Laboratory is to help determine future environmental and human impacts given the releases that have occurred to date and the current waste management practices. In FY 1993, our objectives were to (1) refine and implement the hydrogeologic conceptual models of the regional hydrogeology of western Siberia developed in FY 1992 and develop the detailed, spatially registered digital geologic and hydrologic databases to test them, (2) calibrate the computer implementation of the conceptual models developed in FY 1992, and (3) develop general geologic and hydrologic information and preliminary hydrogeologic conceptual models relevant to the more detailed models of contaminated site hydrogeology. Calibration studies of the regional hydrogeologic computer model suggest that most precipitation entering the ground-water system moves in the near-surface part of the system and discharges to surface waters relatively near its point of infiltration. This means that wastes discharged to the surface and near-surface may not be isolated as well as previously thought, since the wastes may be carried to the surface by gradually rising ground waters

System for the hydrogeologic analysis of uranium mill waste disposal sites

International Nuclear Information System (INIS)

Osiensky, J.L.

1983-01-01

Most of the uranium mill wastes generated before 1977 are stored in unlined tailings ponds. Seepage from some of these ponds has been of sufficient severity that the US Nuclear Regulatory Commission (NRC) has required the installation of withdrawal wells to remove the contaminated groundwater. Uranium mill waste disposal facilities typically are located in complex hydrogeologic environments. This research was initiated in 1980 to analyze hydrogeologic data collected at seven disposal sites in the US that have experienced problems with groundwater contamination. The characteristics of seepage migration are site specific and are controlled by the hydrogeologic environment in the vicinity of each tailings pond. Careful monitoring of most seepage plumes was not initiated until approximately 1977. These efforts were accelerated as a consequence of the uranium Mill Tailings Act of 1979. Some of the data collected at uranium mill waste disposal sites in the past are incomplete and some were collected by methods that are outdated. Data frequently were collected in sequences which disrupted the continuity of the hydrogeologic analysis and decreased the effectiveness of the data collection programs. Evaluation of data collection programs for seven uranium mill waste disposal sites in the US has led to the development and presentation herein of a system for the hydrogeologic analysis of disposal sites

A field experiment on the controls of sediment transport on bedrock erosion

Science.gov (United States)

Beer, A. R.; Turowski, J. M.; Fritschi, B.; Rieke-Zapp, D.; Campana, L.; Lavé, J.

2012-12-01

The earth`s surface is naturally shaped by interactions of physical and chemical processes. In mountainous regions with steep topography river incision fundamentally controls the geomorphic evolution of the whole landscape. There, erosion of exposed bedrock sections by fluvial sediment transport is an important mechanism forming mountain river channels. The links between bedload transport and bedrock erosion has been firmly established using laboratory experiments. However, there are only few field datasets linking discharge, sediment transport, impact energy and erosion that can be used for process understanding and model evaluation. To fill this gap, a new measuring setup has been commissioned to raise an appropriate simultaneous dataset of hydraulics, sediment transport and bedrock erosion at high temporal and spatial resolution. Two natural stone slabs were installed flush with the streambed of the Erlenbach, a gauged stream in the Swiss Pre-Alps. They are mounted upon force sensors recording vertical pressure und downstream shear caused by passing sediment particles. The sediment transport rates can be assessed using geophone plates and an automated moving basket system taking short-term sediment samples. These devices are located directly downstream of the stone slabs. Bedrock erosion rates are measured continuously with erosion sensors at sub-millimeter accuracy at three points on each slab. In addition, the whole slab topography is surveyed with photogrammetry and a structured-light 3D scanner after individual flood events. Since the installation in 2011, slab bedrock erosion has been observed during several transport events. We discuss the relation between hydraulics, bedload transport, resulting pressure forces on the stone slabs and erosion rates. The aim of the study is the derivation of an empirical process law for fluvial bedrock erosion driven by moving sediment particles.

Durable terrestrial bedrock predicts submarine canyon formation

Science.gov (United States)

Smith, Elliot; Finnegan, Noah J.; Mueller, Erich R.; Best, Rebecca J.

2017-01-01

Though submarine canyons are first-order topographic features of Earth, the processes responsible for their occurrence remain poorly understood. Potentially analogous studies of terrestrial rivers show that the flux and caliber of transported bedload are significant controls on bedrock incision. Here we hypothesize that coarse sediment load could exert a similar role in the formation of submarine canyons. We conducted a comprehensive empirical analysis of canyon occurrence along the West Coast of the contiguous United States which indicates that submarine canyon occurrence is best predicted by the occurrence of durable crystalline bedrock in adjacent terrestrial catchments. Canyon occurrence is also predicted by the flux of bed sediment to shore from terrestrial streams. Surprisingly, no significant correlation was observed between canyon occurrence and the slope or width of the continental shelf. These findings suggest that canyon incision is promoted by greater yields of durable terrestrial clasts to the shore.

An evaluation of hydrogeologic data of crystalline rock systems

International Nuclear Information System (INIS)

Raven, K.G.; Lafleur, D.W.

1986-12-01

This report presents a detailed review of hydrogeologic data collected as part of various research programs investigating fractured crystalline rock around the world. Based on the available information describing the test equipment, test methods and analytical techniques, the data have been assessed in terms of their reliability and representativeness, and likely error ranges have been assigned. The data reviewed include both hydrogeologic parameters, such as permeability, storage coefficient components (principally porosity), and fracture characteristic data

Current status of regional hydrogeological studies and numerical simulations on geological disposal

International Nuclear Information System (INIS)

Nakao, Shinsuke; Kikuchi, Tsuneo; Ishido, Tsuneo

2004-01-01

Current status of regional hydrogeological studies on geological disposal including hydrogeological modeling using numerical simulators is reviewed in this report. A regional scale and boundary conditions of numerical models are summarized mainly from the results of the RHS (regional hydrogeological study) project conducted by Japan Nuclear Cycle Development Institute (JNC) in the Tono area. We also refer to the current conceptual modes of hydrology and numerical models of unsaturated zone flow at Yucca Mountain, Nevada, which is the arid site proposed for consideration as the United States' first underground high-level radioactive waste repository. Understanding behavior of a freshwater-saltwater transition zone seems to play a key role in the hydrogeological modeling in a coastal region. Technical features of a numerical simulator as a tool for geothermal reservoir modeling is also briefly described. (author)

Evaluation of bedrock mainly composed of volcanic aggregate rocks at the Higashidori Nuclear Power Station

International Nuclear Information System (INIS)

Hashimoto, Shuichi; Miwa, Tadashi; Nishidachi, Masayuki

2000-01-01

When carrying out engineering evaluation on foundation bedrock for important constructions such as nuclear power station, dam, and so forth, it is required as a premise on carrying out various surveys, tests, and analyses to select adequate geological elements, to classify them to some groups capable of regarding as a common engineering property, and to rate them. On a hard bedrock, there is a classification method with relatively higher versatility adding condition of crack and weathering to performances at each site as an index, but on a soft one, most of its classification are carried out individually for its site in response to an index caused by the bedrock itself. Here were shown the results carried out some bedrock classifications on a base of grouping for rock sorts and rock phases, according to some concepts on a draft of the standard on the soft bedrock classification due to the nuclear engineering committee of the Japan Society of Civil Engineers, a reference draft on the soft bedrock classification of the 'Technical indications on seismic resistance design of the nuclear power station' of the Japan Electric Association, (JEAG4601-1987), and so forth. As a result applied the reference draft on the soft bedrock, and so forth to the bedrock at the Higashidori Nuclear Power Station composed of volcanic aggregate rocks of the Miocene epoch of the new Tertiary system, an adequate engineering evaluation was made possible by making grouping of rock sorts and rock phases to a foundation. And, on property evaluation of the quality changed vein, as a result of various tests, appropriate properties could be obtained. (G.K.)

Abiotic controls of emergent macrophyte density in a bedrock channel - The Cahaba River, AL (USA)

Science.gov (United States)

Vaughn, Ryan S.; Davis, Lisa

2015-10-01

Research examining bedrock channels is growing. Despite this, biotic-abiotic interactions remain a topic mostly addressed in alluvial systems. This research identified hydrogeomorphic factors operating at the patch-scale (100-102 m) in bedrock shoals of the Cahaba River (AL) that help determine the distribution of the emergent aquatic macrophyte, Justicia americana. Macrophyte patch density (number of stems/m2) and percent bedrock void surface area (rock surface area/m2 occupied by joints, fractures, and potholes) were measured (n = 24 within two bedrock shoals) using stem counts and underwater photography, respectively. One-dimensional hydrologic modeling (HEC-RAS 4.1.0) was completed for a section within a shoal to examine velocity and channel depth as controlling variables for macrophyte patch density. Results from binary logistic regression analysis identified depth and velocity as good predictors of the presence or absence of Justicia americana within shoal structures (depth p = 0.001, velocity p = 0.007), which is a similar finding to previous research conducted in alluvial systems. Correlation analysis between bedrock surface void area and stem density demonstrated a statistically significant positive correlation (r = 0.665, p = 0.01), elucidating a link between abiotic-biotic processes that may well be unique to bedrock channels. These results suggest that the amount of void space present in bedrock surfaces, in addition to localized depth and velocity, helps control macrophyte patch density in bedrock shoal complexes. The utility of geomorphology in explaining patch-scale habitat heterogeneity in this study highlights geomorphology's potential to help understand macrophyte habitat heterogeneity at the reach scale, while also demonstrating its promise for mapping and understanding habitat heterogeneity at the system scale.

An integrated theoretical and practical approach for teaching hydrogeology

Science.gov (United States)

Bonomi, Tullia; Fumagalli, Letizia; Cavallin, Angelo

2013-04-01

Hydrogeology as an earth science intersects the broader disciplines of geology, engineering, and environmental studies but it does not overlap fully with any of them. It is focused on its own range of problems and over time has developed a rich variety of methods and approaches. The resolution of many hydrogeological problems requires knowledge of elements of geology, hydraulics, physics and chemistry; moreover in recent years the knowledge of modelling techniques has become a necessary ability. Successful transfer of all this knowledge to the students depends on the breadth of material taught in courses, the natural skills of the students and any practical experience the students can obtain. In the Department of Earth and Environmental Sciences of the University of Milano-Bicocca, the teaching of hydrogeology is developed in three inter-related courses: 1) general hydrogeology, 2) applied hydrogeology, 3) groundwater pollution and remediation. The sequence focuses on both groundwater flux and contaminant transport, supplemented by workshops involving case studies and computer labs, which provide the students with practical translation of the theoretical aspects of the science into the world of work. A second key aspect of the program utilizes the students' skill at learning through online approaches, and this is done through three approaches: A) by developing the courses on a University e-learning platform that allows the students to download lectures, articles, and teacher comments, and to participate in online forums; B) by carring out exercises through computer labs where the student analyze and process hydrogeological data by means of different numerical codes, that in turn enable them to manage databases and to perform aquifer test analysis, geostatistical analysis, and flux and transport modelling both in the unsaturated and saturated zone. These exercises are of course preceded by theoretical lectures on codes and software, highlighting their features and

The potential for cold climate conditions and permafrost in Forsmark in the next 60 000 years

Energy Technology Data Exchange (ETDEWEB)

Brandefelt, Jenny; Naeslund, Jens-Ove [Svensk Kaernbraenslehantering, Stockholm (Sweden); Zhang, Qiong [Dept. of Meteorology, Stockholm Univ., Stockholm (Sweden); Hartikainen, Juha [School of Engineering, Aalto Univ., Aalto (Finland)

2013-05-15

This report presents results of a study devoted to extend the current knowledge of the climate in Sweden in the next {approx}60,000 years (60 ka). Specifically, the potential of cold climate and permafrost development in south-central Sweden, and in the Forsmark region, over this time horizon was investigated. The climate system is an interactive system consisting of five major components: the atmosphere, the hydrosphere, the cryo sphere, the land surface and the biosphere, forced or influenced by various external forcing mechanisms, of which the most important is the Sun. Also the direct effect of human activities on the climate system is considered an external forcing. The latitudinal and seasonal distribution of incoming solar radiation (insolation) varies on millennial time scales due to variations in the Earth's orbit and axial tilt. These variations, together with variations in the atmospheric CO{sub 2} concentration, are viewed as two main factors in determining the climate variation between interglacial (warmer) and glacial (colder) climates. Summer insolation at high northern latitudes is at a minimum 17 ka and 54 ka after present (AP). These periods were therefore identified as potential future periods of cold climate conditions in high northern latitudes in general and in south-central Sweden in particular. Due to human emissions of carbon to the atmosphere, the atmospheric CO{sub 2} concentration is currently 392 ppmv (2011 AD), a substantial increase as compared to the range of atmospheric CO{sub 2} concentrations of 180-295 ppmv found in ice cores for the last 400 ka. The future atmospheric CO{sub 2} concentration is determined by i) future human carbon emissions to the atmosphere, ii) possible emissions due to feedbacks in the climate system, and iii) by the global carbon cycle. To investigate the potential of cold climate conditions in south-central Sweden in the next 60 ka the future air temperature in Forsmark was estimated based on

The potential for cold climate conditions and permafrost in Forsmark in the next 60 000 years

International Nuclear Information System (INIS)

Brandefelt, Jenny; Naeslund, Jens-Ove; Zhang, Qiong; Hartikainen, Juha

2013-05-01

This report presents results of a study devoted to extend the current knowledge of the climate in Sweden in the next ∼60,000 years (60 ka). Specifically, the potential of cold climate and permafrost development in south-central Sweden, and in the Forsmark region, over this time horizon was investigated. The climate system is an interactive system consisting of five major components: the atmosphere, the hydrosphere, the cryo sphere, the land surface and the biosphere, forced or influenced by various external forcing mechanisms, of which the most important is the Sun. Also the direct effect of human activities on the climate system is considered an external forcing. The latitudinal and seasonal distribution of incoming solar radiation (insolation) varies on millennial time scales due to variations in the Earth's orbit and axial tilt. These variations, together with variations in the atmospheric CO 2 concentration, are viewed as two main factors in determining the climate variation between interglacial (warmer) and glacial (colder) climates. Summer insolation at high northern latitudes is at a minimum 17 ka and 54 ka after present (AP). These periods were therefore identified as potential future periods of cold climate conditions in high northern latitudes in general and in south-central Sweden in particular. Due to human emissions of carbon to the atmosphere, the atmospheric CO 2 concentration is currently 392 ppmv (2011 AD), a substantial increase as compared to the range of atmospheric CO 2 concentrations of 180-295 ppmv found in ice cores for the last 400 ka. The future atmospheric CO 2 concentration is determined by i) future human carbon emissions to the atmosphere, ii) possible emissions due to feedbacks in the climate system, and iii) by the global carbon cycle. To investigate the potential of cold climate conditions in south-central Sweden in the next 60 ka the future air temperature in Forsmark was estimated based on simulations with an Earth system model

Updated model for radionuclide transport in the near-surface till at Forsmark - Implementation of decay chains and sensitivity analyses

International Nuclear Information System (INIS)

Pique, Angels; Pekala, Marek; Molinero, Jorge; Duro, Lara; Trinchero, Paolo; Vries, Luis Manuel de

2013-02-01

The Forsmark area has been proposed for potential siting of a deep underground (geological) repository for radioactive waste in Sweden. Safety assessment of the repository requires radionuclide transport from the disposal depth to recipients at the surface to be studied quantitatively. The near-surface quaternary deposits at Forsmark are considered a pathway for potential discharge of radioactivity from the underground facility to the biosphere, thus radionuclide transport in this system has been extensively investigated over the last years. The most recent work of Pique and co-workers (reported in SKB report R-10-30) demonstrated that in case of release of radioactivity the near-surface sedimentary system at Forsmark would act as an important geochemical barrier, retarding the transport of reactive radionuclides through a combination of retention processes. In this report the conceptual model of radionuclide transport in the quaternary till at Forsmark has been updated, by considering recent revisions regarding the near-surface lithology. In addition, the impact of important conceptual assumptions made in the model has been evaluated through a series of deterministic and probabilistic (Monte Carlo) sensitivity calculations. The sensitivity study focused on the following effects: 1. Radioactive decay of 135 Cs, 59 Ni, 230 Th and 226 Ra and effects on their transport. 2. Variability in key geochemical parameters, such as the composition of the deep groundwater, availability of sorbing materials in the till, and mineral equilibria. 3. Variability in hydraulic parameters, such as the definition of hydraulic boundaries, and values of hydraulic conductivity, dispersivity and the deep groundwater inflow rate. The overarching conclusion from this study is that the current implementation of the model is robust (the model is largely insensitive to variations in the parameters within the studied ranges) and conservative (the Base Case calculations have a tendency to

Root distribution and seasonal water status in weathered granitic bedrock under chaparral

Science.gov (United States)

P. D. Sternberg; M. A. Anderson; R. C. Graham; J. L. Beyers; K. R. Tice

1996-01-01

Soils in mountainous terrain are often thin and unable to store sufficient water to support existing vegetation through dry seasons. This observation has led to speculation about the role of bedrock in supporting plant growth in natural ecosystems, since weathered bedrocks often have appreciable porosity and, like soil, can store and transmit water. This study, within...

Blast fracturing of bedrock to enhance recovery of contaminated groundwater

International Nuclear Information System (INIS)

Holzman, L.R.; Harvey, E.M.; McKee, R.C.E.; Katsabanis, T.

1992-01-01

Petroleum hydrocarbons releasd from a pipeline at a site in southern Ontario had contaminated a fractured dolostone bedrock aquifer. To remediate the site, contaminated groundwater was pumped from the downgradient edge of the hydrocarbon plume and injected into an upgradient area after treatment. Contaminant flow pathways in the fractured bedrock aquifer were found to be complex and erratic. It was anticipated that contaminated groundwater could escape the influence of a line of closely spaced recovery wells. In order to capture the migrating contaminants effectively, improve communication between recovery wells, and optimize pumping efficiencies, a rubble zone was created by drilling and blasting the rock. Using 140 blastholes, the bedrock was fractured to a depth of 4 m over a distance of 200 m. Similarly, an additional 80 blastholes were used to blast fracture 100 m of bedrock to a depth of 4 m in the recharge area to enhance injection of treated water to the aquifer. Various blasthole spacings and explosive loadings and patterns were tested to fracture the rock effectively while minimizing the impact on the nearby pipeline and neighboring residences. Vibrations were carefully monitored using several seismographs. Pump tests conducted before and after the blast indicated the hydraulic connection between the naturally occurring fractures had greatly improved. Monitoring conducted after startup of the pump-treat-and-inject system has confirmed the fracturing provides effective capture and injection of the groundwater. 3 refs., 3 figs., 1 tab

Hydrogeology - HYDROGEOL_SETTINGS_IN: Hydrogeologic Terrains and Settings of Indiana (Indiana Geological Survey, 1:100,000, Polygon Shapefile)

Data.gov (United States)

NSGIC State | GIS Inventory — HYDROGEOL_SETTINGS_IN is a polygon shapefile that shows hydrogeologic terrains and settings of Indiana. The methodology of the investigation and definitions of terms...

A review of published literature on the effects of permafrost on the hydrogeochemistry of bedrock

International Nuclear Information System (INIS)

Cascoyne, M.

2000-06-01

of seawater, enhanced or depleted sulphate concentrations in certain groundwaters, and lighter isotopic signature of the saline waters caused by the ice-water isotopic fractionation. This review has found that salt-rejection processes undoubtedly will have occurred in groundwaters in the marine sediments and bedrock of the Baltic coast during the Pleistocene. Deeply penetrating permafrost in the bedrock would cause relatively pure water to form as ice in fractures and displace residual saline fluids, under density flow, to greater depths. The process could have occurred to a sufficient extent that large volumes of saline water were generated, some of which may currently remain in the fractured rock. In these waters, loss of sulphate by mirabilite precipitation would be expected to have occurred but, on warming and degradation of the permafrost, lower-salinity meltwaters would re-dissolve the mirabilite, giving rise to a SO 4 -rich groundwater. This may be the origin of groundwater that is currently identified as Litorina Sea water at the Aespoe and Olkiluoto sites. This mechanism differs from that suggested by Israeli workers who propose freezing of open seawater and infiltration of residual brines into the bedrock followed by lateral migration inland. The hypothesis presented here, of formation of saline waters and brines by permafrost aggradation and salt-rejection is more acceptable from a hydrogeological standpoint because the saline waters are formed in situ and need not migrate laterally. Further field evidence, coupled with modelling of depths of permafrost penetration, could be used to assess the volume and concentration of saline groundwater formed as a result of downward advancement of permafrost in the crystalline bedrock. (orig.)

A review of published literature on the effects of permafrost on the hydrogeochemistry of bedrock

International Nuclear Information System (INIS)

Gascoyne, M.

2000-04-01

, enhanced or depleted sulphate concentrations in certain groundwaters, and lighter isotopic signature of the saline waters caused by the ice-water isotopic fractionation. This review has found that salt-rejection processes undoubtedly will have occurred in groundwaters in the marine sediments and bedrock of the Baltic coast during the Pleistocene. Deeply penetrating permafrost in the bedrock would cause relatively pure water to form as ice in fractures and displace residual saline fluids,under density flow, to greater depths. The process could have occurred to a sufficient extent that large volumes of saline water were generated, some of which may currently remain in the fractured rock. In these waters,loss of sulphate by mirabilite precipitation would be expected to have occurred but, on warming and degradation of the permafrost,lower-salinity meltwaters would re-dissolve the mirabilite, giving rise to a SO 4 -rich groundwater. This may be the origin of groundwater that is currently identified as Litorina Sea water at the Aespoe and Olkiluoto sites. This mechanism differs from that suggested by Israeli workers who propose freezing of open seawater and infiltration of residual brines into the bedrock followed by lateral migration inland. The hypothesis presented here, of formation of saline waters and brines by permafrost aggradation and salt-rejection is more acceptable from a hydrogeological standpoint because the saline waters are formed in situ and need not migrate laterally. Further field evidence, coupled with modelling of depths of permafrost penetration, could be used to assess the volume and concentration of saline groundwater formed as a result of downward advancement of permafrost in the crystalline bedrock

A review of published literature on the effects of permafrost on the hydrogeochemistry of bedrock

Energy Technology Data Exchange (ETDEWEB)

Gascoyne, M. [Gascoyne GeoProjects Inc., Pinawa (Canada)

2000-04-01

seawater, enhanced or depleted sulphate concentrations in certain groundwaters, and lighter isotopic signature of the saline waters caused by the ice-water isotopic fractionation. This review has found that salt-rejection processes undoubtedly will have occurred in groundwaters in the marine sediments and bedrock of the Baltic coast during the Pleistocene. Deeply penetrating permafrost in the bedrock would cause relatively pure water to form as ice in fractures and displace residual saline fluids,under density flow, to greater depths. The process could have occurred to a sufficient extent that large volumes of saline water were generated, some of which may currently remain in the fractured rock. In these waters,loss of sulphate by mirabilite precipitation would be expected to have occurred but, on warming and degradation of the permafrost,lower-salinity meltwaters would re-dissolve the mirabilite, giving rise to a SO{sub 4}-rich groundwater. This may be the origin of groundwater that is currently identified as Litorina Sea water at the Aespoe and Olkiluoto sites. This mechanism differs from that suggested by Israeli workers who propose freezing of open seawater and infiltration of residual brines into the bedrock followed by lateral migration inland. The hypothesis presented here, of formation of saline waters and brines by permafrost aggradation and salt-rejection is more acceptable from a hydrogeological standpoint because the saline waters are formed in situ and need not migrate laterally. Further field evidence, coupled with modelling of depths of permafrost penetration, could be used to assess the volume and concentration of saline groundwater formed as a result of downward advancement of permafrost in the crystalline bedrock.

A review of published literature on the effects of permafrost on the hydrogeochemistry of bedrock

Energy Technology Data Exchange (ETDEWEB)

Cascoyne, M. [Gascoyne GeoProjects Inc. (Canada)

2000-06-01

formed on freezing of seawater, enhanced or depleted sulphate concentrations in certain groundwaters, and lighter isotopic signature of the saline waters caused by the ice-water isotopic fractionation. This review has found that salt-rejection processes undoubtedly will have occurred in groundwaters in the marine sediments and bedrock of the Baltic coast during the Pleistocene. Deeply penetrating permafrost in the bedrock would cause relatively pure water to form as ice in fractures and displace residual saline fluids, under density flow, to greater depths. The process could have occurred to a sufficient extent that large volumes of saline water were generated, some of which may currently remain in the fractured rock. In these waters, loss of sulphate by mirabilite precipitation would be expected to have occurred but, on warming and degradation of the permafrost, lower-salinity meltwaters would re-dissolve the mirabilite, giving rise to a SO{sub 4}-rich groundwater. This may be the origin of groundwater that is currently identified as Litorina Sea water at the Aespoe and Olkiluoto sites. This mechanism differs from that suggested by Israeli workers who propose freezing of open seawater and infiltration of residual brines into the bedrock followed by lateral migration inland. The hypothesis presented here, of formation of saline waters and brines by permafrost aggradation and salt-rejection is more acceptable from a hydrogeological standpoint because the saline waters are formed in situ and need not migrate laterally. Further field evidence, coupled with modelling of depths of permafrost penetration, could be used to assess the volume and concentration of saline groundwater formed as a result of downward advancement of permafrost in the crystalline bedrock. (orig.)

HYDROGEOLOGICAL AND HYDROCHEMICAL FEATURES OF KALNIK MASSIF

Directory of Open Access Journals (Sweden)

Vinko Mraz

2008-12-01

Full Text Available Kalničko gorje consists of Cretaceous – Holocene sediments, which can be in hydrogeological sense classified in three hydrogeological units: (1 northern area from central massive of Kalnik, consists of Cretaceous and low Miocene impermeable and low permeable sediments which are hydrogeological barrier and low permeable Cretaceous eruptive sediments ; (2 Kalnik massive consists of Paleogen and Baden permeable carbonate – clastic sediments, which are aquifer; (3 southern Kalnik area consists of Neogene low permeable sediments and Quaternary medium permeable unconsolidated deposits. In the hydrogelogical units are several aquifers types: (i Paleogen carbonate aquifer consists of limestone – dolomite breccia and this is the most important aquifer in the Kalnik area; (ii Baden carbonate aquifer consists of lithothamnium, lithothamnium limestone, sandstone and breccia-conglomerate and it has high permeability, especially through the karst morphological features; (iii Quaternary alluvial aquifers – the most important is in the valley of the Kamešnica river and it’s permeability varies from poor to good depending on granulometric properties; (iv Cretaceous eruptive aquifer from which in the Apatovac area is abstraction of mineral water. The aquifers of the Kalnik area are very vulnerable considering the hydrogeological properties of the area. Nevertheless, physical, physicalchemical, and chemical properties of groundwater in the Kalnik area are showing that waters are of very good quality. The reasons of good quality of waters are that the area is poorly populated and there is no potential pollutant. The area is very valuable and important natural resource for water supply of whole region. In the future it is necessary to provide good protection and sustainable water management to obtain today’s good quality and quantity of groundwater (the paper is published in Croatian.

Recent hydrogeologic study of the Vis island

Directory of Open Access Journals (Sweden)

Janislav Kapelj

2002-12-01

Full Text Available The Vis Island belongs to the group of the Middle Dalmatian islands. It comprises an area of about 90.2 km2. Morphologically, three belts of highlands and two depressions with karst poljes are significant. The highest point on the island is Hum with 587 m a.s.l. theisland’s water supply is organized from the water-supply station “Korita”, situated in the central part of island, in tectonically formed depression. There are two additional capturedobjects: the well K-1 above the Komiža town and the spring “Pizdica”. The most important hydrogeological role on the island have two hydrogeological barriers, one in the KomižaBay, completely made of impermeable igneous and clastic rocks, and another one, the recently recognized relative barrier in the area of Dra~evo, Plisko and Velo polje. Since the island karst aquifer is in permanent dynamic relation with seawater, classical geologic,structural and hydrogeologic investigations have been performed with application of hydrogeochemical methods taking into account the natural chemical tracer content of groundwater and its variations in different hydrologic and vegetation conditions. Precipitationregime is very unfavorable with regard to the recharging of island’s aquifer, because dry periods are usually very long. During the summer tourist season, when the number of inhabitants and fresh water consumption considerably increase, amounts of island’sgroundwater suitable for water supply and irrigation rapidly decrease. Sometimes, insufficient quantity of fresh water on the Vis Island causes restrictions. Concerning the development of tourist potential and the present agricultural activities, summer lack ofwater is a serious restrictive factor. Some results of the performed hydrogeological study, important as a basis for island’s fresh water potential assessment, will be presented.

Bedrock Geologic Map of the Underhill quadrangle, Vermont

Data.gov (United States)

Vermont Center for Geographic Information — Digital Data from VG03-4B Doolan, B., Cherchetti, L., Holt, J., Ryan, J., Hengstenburg, C., and Rosencrantz, E., 2003,�Bedrock Geologic Map of the Underhill...

Bedrock Geologic Map of the Bristol, VT Quadrangle

Data.gov (United States)

Vermont Center for Geographic Information — Digital data from VG13-1 Kim, J, Weber, E, and Klepeis, K, 2013, Bedrock Geologic Map of the Bristol, VT Quadrangle: Vermont Geological Survey Open File Report...

Rural Community Development: Bedrock for National Development ...

African Journals Online (AJOL)

This paper advocates that community development is the bedrock for national development. For any meaningful development to take place, whether national or global development must have its building blocks or firm-root in rural development. However, the rural communities are characterized by isolation from ideas and ...

Groundwater management in coastal zones and on islands in crystalline bedrock areas of Sweden

Science.gov (United States)

Banzhaf, Stefan; Ekström, Linda Louise; Ljungkvist, Andreas; Granberg, Maria; Merisalu, Johanna; Pokorny, Sebastian; Barthel, Roland

2017-04-01

Groundwater problems in coastal regions are usually not associated with the sparsely populated shores of water-rich Scandinavia. However, the combination of geology and the specific conditions of water usage create challenges even there. Along the Swedish coast, much of the groundwater occurs in fractured bedrock or in relatively small, shallow, and isolated quaternary sedimentary formations. Those aquifers cannot provide water to larger permanent settlements and are thus neither useful for the public water supply nor have previously received much attention from water authorities or researchers. However, of the 450,000 private wells in Sweden, many are located in coastal areas or on islands, creating pressure on groundwater resources in summer months as periods with low or no natural groundwater recharge. In view of the increasing water demand, as well as the awareness of environmental impacts and climate change, Swedish municipalities now recognize groundwater usage in coastal areas is a major concern. Here, we present the results of an investigation on the "Koster" archipelago which forms a microcosm of coastal zone groundwater problems in Sweden. Koster's geology is dominated by fractured, crystalline bedrock with occasional shallow quaternary deposits in between. With around 300 permanent residents, and up to 6,000 summer guests in peak holiday season, the existing water supply based on 800 private wells is at its limit. Water availability forms an obstacle to future development and the current mode of operation is unsustainable. Therefore, the municipality must decide how to secure future water supply which involves complex legal problems, as well as social, cultural, economic, hydrogeological, and environmental questions. As there are no observation wells on the islands, we used approximately 220 of the 800 wells (65% dug and shallow, 35% drilled and up to 120m deep) for our monitoring. Additionally, water samples were collected by property owners on four

The effect of wet-dry weathering on the rate of bedrock river channel erosion by saltating gravel

Science.gov (United States)

Inoue, Takuya; Yamaguchi, Satomi; Nelson, Jonathan M.

2017-01-01

Previous work has shown that the bedrock erosion rate E because of collisions of saltating bedload can be expressed by E = βqb(1-Pc), where qb is the sediment transport rate, Pc is the extent of alluvial cover, and β is the abrasion coefficient. However, the dependence of the abrasion coefficient on the physical characteristics of the bedrock material is poorly known, and in particular, the effects of wet-dry weathering on the saltation-abrasion bedrock incision has not been specifically characterized. Observation suggests that the typical wet-dry cycling of exposed bedrock in river beds gives rise to cracks and voids that are likely to alter the incision rate of the material when subjected to impacts of moving sediment. In this study, flume experiments are performed to develop an understanding of how wet-dry cycling affects the rock tensile strength and the bedrock erosion rate. To represent the physical effects of weathering, boring cores taken from natural bedrock channel are exposed to artificial wet-dry cycles. The experimental results suggest the following: (1) the abrasion coefficient for fresh bedrock is estimated by β = 1.0 × 10− 4σT− 2(d/ksb)0.5, where σT is the tensile strength, d is the diameter of colliding gravel, and ksb is the hydraulic roughness height of bedrock; (2) the tensile strength of the bedrock decreases exponentially as a result of repeated wet-dry cycles, σT/σT0 = exp (-CTNWa0/σT0), where σT0 is the initial tensile strength, Wa0 is the initial normalized rate of water absorption., N is the number of wet-dry cycles, and CT is a constant; (3) the erosion rate of fresh bedrock depends on the inverse of the square of tensile strength, but the erosion rate of weathered bedrock depends on the − 1.5 power of tensile strength.

On uncertainty quantification in hydrogeology and hydrogeophysics

Science.gov (United States)

Linde, Niklas; Ginsbourger, David; Irving, James; Nobile, Fabio; Doucet, Arnaud

2017-12-01

Recent advances in sensor technologies, field methodologies, numerical modeling, and inversion approaches have contributed to unprecedented imaging of hydrogeological properties and detailed predictions at multiple temporal and spatial scales. Nevertheless, imaging results and predictions will always remain imprecise, which calls for appropriate uncertainty quantification (UQ). In this paper, we outline selected methodological developments together with pioneering UQ applications in hydrogeology and hydrogeophysics. The applied mathematics and statistics literature is not easy to penetrate and this review aims at helping hydrogeologists and hydrogeophysicists to identify suitable approaches for UQ that can be applied and further developed to their specific needs. To bypass the tremendous computational costs associated with forward UQ based on full-physics simulations, we discuss proxy-modeling strategies and multi-resolution (Multi-level Monte Carlo) methods. We consider Bayesian inversion for non-linear and non-Gaussian state-space problems and discuss how Sequential Monte Carlo may become a practical alternative. We also describe strategies to account for forward modeling errors in Bayesian inversion. Finally, we consider hydrogeophysical inversion, where petrophysical uncertainty is often ignored leading to overconfident parameter estimation. The high parameter and data dimensions encountered in hydrogeological and geophysical problems make UQ a complicated and important challenge that has only been partially addressed to date.

The geology and hydrogeology of Sellafield: an overview

International Nuclear Information System (INIS)

Chaplow, Robert

1996-01-01

Nirex is responsible for providing and managing a national facility for solid intermediate-level and low-level radioactive waste. Geological and hydrogeological investigations have been in progress at Sellafield in west Cumbria since 1989 aimed at determining whether or not the site is suitable for such a deep repository. Geological investigations have included the drilling of 20 deep boreholes with over 20 000 metres of drilling, together with almost 2000 line kilometres of seismic surveys and over 8000 line kilometres of airborne geophysical surveys. Hydrogeological testing and groundwater sampling and testing have provided additional information on the ground conditions at the site. (author)

Preliminary assessment of potential underground stability (wedge and spalling) at Forsmark, Simpevarp and Laxemar sites

Energy Technology Data Exchange (ETDEWEB)

Martin, Derek [Univ. of Alberta, Edmonton (Canada). Geotechnical Engineering

2005-12-15

In SKB's Underground Design Premises the objective in the early design phase is to estimate if there is sufficient space for the repository at a site. One of the conditions that could limit the space available is stability of the underground openings, i.e., deposition tunnels and deposition boreholes. The purpose of this report is to provide a preliminary assessment of the potential for wedge instability and spalling that may be encountered at the Forsmark, Simpevarp and Laxemar sites based on information from the site investigations program up to July 30, 2004. The rock mass spalling strength was defined using the in-situ results from SKB's Aespoe Pillar Stability Experiment and AECL's Mine-by Experiment. These experiments suggest that the rock mass spalling strength for crystalline rocks can be estimated as 0.57 of the mean laboratory uniaxial compressive strength. A probability-based methodology utilizing this in-situ rock mass spalling strength has been developed for assessing the risk for spalling in a repository at the Forsmark, Simpevarp and Laxemar sites. The in-situ stresses and the uniaxial compressive strength data from these sites were used as the bases for the analyses. Preliminary findings from all sites suggest that, generally, the risk for spalling increases as the depth of the repository increases, simply because the stress magnitudes increase with depth. The depth at which the risk for spalling is significant, depends on the individual sites which are discussed below. The greatest uncertainty in the spalling analyses for Forsmark is related to the uncertainty in the horizontal stress magnitudes and associated stress gradients with depth. The confidence in these analyses can only be increased by increasing the confidence in the stress and geology model for the site. From the analyses completed it appears that spalling in the deposition tunnels can be controlled by orienting the tunnels approximately parallel to the maximum horizontal

Chemistry data from surface ecosystems in Forsmark and Laxemar-Simpevarp. Site specific data used for estimation of CR and K{sub d} values in SR-Site

Energy Technology Data Exchange (ETDEWEB)

Troejbom, Mats [Mats Troejbom Konsult AB (Sweden); Norden, Sara [Svensk Kaernbraenslehantering AB (Sweden)

2010-11-15

This report is a background report for the biosphere analysis of the SR-Site Safety Assessment. This work aims to compile information from the Forsmark and Laxemar-Simpevarp sites in order to select and provide relevant site data for parameter sed in the Radionuclide Dose Model. This report contains an overview of all available chemistry data from the surface ecosystems at Forsmark and Laxemar-Simpevarp areas, comprising hydrochemistry of shallow groundwater, porewater, lake water, stream water and sea water as well as the chemical composition of the regolith and biota of the terrestrial, limnic and marine ecosystems. Detailed references to data reports are tabulated and all sampling points are shown in a large number of maps in Chapter 2. An explorative analysis in Chapter 3 is the basis for the final selection of site data described in Chapter 4

Interdisciplinary hydrogeologic site characterization at the Nevada Test Site

International Nuclear Information System (INIS)

Hawkins, W.L.; Wagoner, J.L.; Drellack, S.L.

1992-01-01

The Nevada Test Site was established in 1950 as a continental area for testing nuclear devices. Hydrogeologic investigations began in earnest with the US Geological Survey mapping much of the area from 1960 to 1965. Since 1963, all nuclear detonations have been underground. Most tests are conducted in vertical shafts, but a small percentage are conducted in tunnels. The majority of detonation points are above the water table, primarily in volcanic rocks, but sometimes in alluvium. Hydrogeologic investigations began in earnest with the US Geological Survey's mapping of much of the NTS region from 1960 to 1965. Following the BANEBERRY test in December 1970, which produced an accidental release of radioactivity to the atmosphere, the US Department of Energy (then the Atomic Energy Commission) established the Containment Evaluation Panel (CEP). Results of interdisciplinary hydrogeologic investigations for each test location are included in a Containment Prospectus which is thoroughly reviewed by the CEP

Mapping the global depth to bedrock for land surface modelling

Science.gov (United States)

Shangguan, W.; Hengl, T.; Yuan, H.; Dai, Y. J.; Zhang, S.

2017-12-01

Depth to bedrock serves as the lower boundary of land surface models, which controls hydrologic and biogeochemical processes. This paper presents a framework for global estimation of Depth to bedrock (DTB). Observations were extracted from a global compilation of soil profile data (ca. 130,000 locations) and borehole data (ca. 1.6 million locations). Additional pseudo-observations generated by expert knowledge were added to fill in large sampling gaps. The model training points were then overlaid on a stack of 155 covariates including DEM-based hydrological and morphological derivatives, lithologic units, MODIS surfacee reflectance bands and vegetation indices derived from the MODIS land products. Global spatial prediction models were developed using random forests and Gradient Boosting Tree algorithms. The final predictions were generated at the spatial resolution of 250m as an ensemble prediction of the two independently fitted models. The 10-fold cross-validation shows that the models explain 59% for absolute DTB and 34% for censored DTB (depths deep than 200 cm are predicted as 200 cm). The model for occurrence of R horizon (bedrock) within 200 cm does a good job. Visual comparisons of predictions in the study areas where more detailed maps of depth to bedrock exist show that there is a general match with spatial patterns from similar local studies. Limitation of the data set and extrapolation in data spare areas should not be ignored in applications. To improve accuracy of spatial prediction, more borehole drilling logs will need to be added to supplement the existing training points in under-represented areas.

Physically based probability criterion for exceeding radionuclide concentration limits in heterogeneous bedrock

International Nuclear Information System (INIS)

Worman, A.; Xu, S.; Dverstorp, B.

2004-01-01

A significant problem in a risk analysis of the repository for high-level nuclear waste is to estimate the barrier effect of the geosphere. The significant spatial variability of the rock properties implies that migrating RNs encounter a distribution of bedrock properties and mass-transfer mechanisms in different proportions along the transport paths. For practical reasons, we will never be able to know exactly this distribution of properties by performing a reasonable amount of measurements in a site investigation. On the contrary, recent experimental studies reveal that crystalline bedrock can possess a marked heterogeneity of various physical and geochemical properties that potentially may have a certain impact on the transport of RNs in fractured bedrock. Also current field investigation techniques provide only fragmentary information of the properties of the geosphere. This is a basic motivation for treating flows of water and solute elements in groundwaters by means of stochastic continuum models. The stochastic analysis is based on the idea that we know only certain point values of the property fields and use this information to estimate intermediate values. The probabilistic properties of the stochastic analysis are suitable input variables for risk analyses of the relevant sequence of extreme events for which empirical observations are rare or non-existing. The purpose of this paper is to outline the implications of the stochastic approach for estimating probabilities that certain concentration limits are exceeded at discharge points from. the bedrock in case of a leakage from the waste repository. The analysis is restricted to the water flow and solute transport in the bedrock alone without consideration of the full sequence of events in a full risk analysis and the Bayesian statistics involved in such conditioned (and cross-correlated) event series. The focus is on the implication for the risk analysis of the auto-covariance structure in bedrock

Drilling methods to keep the hydrogeological parameters of natural aquifer

International Nuclear Information System (INIS)

Chen Xiaoqin

2004-01-01

In hydrogeological drilling, how to keep the hydrogeological parameters of natural aquifer unchanged is a deeply concerned problem for the technicians, this paper introduces the methods taken by the state-owned 'Red Hill' geological company of Uzbekistan. By the research and contrast of different kinds of flush liquid, the company has found the methods to reduce the negative effects of drilling on the permeability of the vicinal aquifer. (author)

Modelling Waterfall Retreat in Heterogenous Bedrock

Science.gov (United States)

Attal, M.; Hodge, R. A.; Williams, R.; Baynes, E.

2016-12-01

Bedrock rivers are the mediators of environmental change through mountainous landscapes. In response to an increase in uplift rate for example, a "knickpoint" (often materialised as a waterfall) will propagate upstream, separating a domain downstream where the river and its adjacent hillslopes have steepened in response to the change from a "relict" domain upstream which is adjusted to the conditions before the change (Crosby and Whipple 2006). Many studies assume that knickpoint propagation rate scales with drainage area, based on the stream power theory. However, recent studies in a range of locations have found no obvious relationship between knickpoint retreat rate and drainage area, potentially resulting from the stream power law neglecting (i) the influence of sediment on the processes associated with waterfall migration and (ii) thresholds for bedrock detachment (Cook et al. 2013; Mackey et al. 2014; DiBiase et al. 2015; Baynes et al. 2015; Brocard et al. 2016). In this study, we develop a 1D model of waterfall retreat in horizontally bedded bedrock with varying joint spacing. In the model, knickpoint migration is based on two rules: a waterfall will start migrating once the threshold flow depth (a function of knickpoint height and joint spacing) has been exceeded (Lamb and Dietrich 2009), and the migration rate will then be a function of the water-depth-to-waterfall-height ratio, based on experimental results by Baynes (2015). Using a hydrograph based on a Poisson rectangular pulse rainfall simulator (Tucker and Bras 2001), we demonstrate the importance of structure in controlling the speed at which waterfalls migrate but also their number and the length over which they are distributed (Fig. 1). The model is applied to the Jökulsá á Fjöllum, NE Iceland, where rapid migration of waterfalls as a result of discrete events has been identified (Baynes et al. 2015), using new constraints on joint spacing derived from high resolution lidar survey of the gorge

Hydrogeological Characteristics of Groundwater Yield in Shallow ...

African Journals Online (AJOL)

Hydrogeological Characteristics of Groundwater Yield in Shallow Wells of the ... of Water Resources and Lower Niger River Basin Development Authority in Ilorin. ... moment correlation, multiple and stepwise multiple regression analysis.

Hydrogeology and water quality of the Leetown area, West Virginia

Science.gov (United States)

Kozar, Mark D.; McCoy, Kurt J.; Weary, David J.; Field, Malcolm S.; Pierce, Herbert A.; Schill, William Bane; Young, John A.

2008-01-01

The U.S. Geological Survey’s Leetown Science Center and the co-located U.S. Department of Agriculture’s National Center for Cool and Cold Water Aquaculture both depend on large volumes of cold clean ground water to support research operations at their facilities. Currently, ground-water demands are provided by three springs and two standby production wells used to augment supplies during periods of low spring flow. Future expansion of research operations at the Leetown Science Center is dependent on assessing the availability and quality of water to the facilities and in locating prospective sites for additional wells to augment existing water supplies. The hydrogeology of the Leetown area, West Virginia, is a structurally complex karst aquifer. Although the aquifer is a karst system, it is not typical of most highly cavernous karst systems, but is dominated by broad areas of fractured rock drained by a relatively small number of solution conduits. Characterization of the aquifer by use of fluorometric tracer tests, a common approach in most karst terranes, therefore only partly defines the hydrogeologic setting of the area. In order to fully assess the hydrogeology and water quality in the vicinity of Leetown, a multi-disciplinary approach that included both fractured rock and karst research components was needed. The U.S. Geological Survey developed this multi-disciplinary research effort to include geologic, hydrologic, geophysical, geographic, water-quality, and microbiological investigations in order to fully characterize the hydrogeology and water quality of the Leetown area, West Virginia. Detailed geologic and karst mapping provided the framework on which hydrologic investigations were based. Fracture trace and lineament analysis helped locate potential water-bearing fractures and guided installation of monitoring wells. Monitoring wells were drilled for borehole geophysical surveys, water-quality sampling, water-level measurements, and aquifer tests to

Perspectives of natural isotopes application for solving hydrogeological problems of mineral deposits

International Nuclear Information System (INIS)

Rozkowski, A.

1978-01-01

Results of hydrogeological studies made with use of natural isotopes and carried out within the Lublin Coal Field are presented in the paper. The studies have proved advantageous possibilities of isotope technique application for solving the hydrogeological problems of mineral deposits. Examination of isotope relations in ground waters complements traditional hydrogeological methods. This trend of complex investigations enables solving some peculiar hydrodynamic and hydrochemical problems. Exact recognition of these conditions is required to elaborate out proper prognosis on water content degree in given deposit and on value of ground water inflow into areas of designed mines. (author)

Mineralization of the ancient hydrogeological conditions in the northeast of Ordos basin

International Nuclear Information System (INIS)

Gao Junyi

2012-01-01

Ordos basin, North East, to the Eocene as a turning point, in the generation of the ancient hydrogeological conditions have distinct changes experienced at least two ancient evolution of hydrogeological conditions, that is closed in the early flow into basin Late open drain basin. Closed in the early period of the inner flow basin, since the purpose of layer deposition, the direction of the ancient hydrodynamic interlayer oxidation is consistent with the direction of oxidation. Hydrogeological conditions of the ancient point of view, in the Ordos basin, North East looking for interlayer oxidation zone type uranium has a guiding role. (author)

Synthetic hydrogeological study on Beishan preselected area for high-level radioactive waste repository in China

International Nuclear Information System (INIS)

Guo Yonghai; Su Rui; Ji Ruili; Wang Hailong; Liu Shufen; Zong Zihua; Dong Jiannan; Zhang Ming

2014-01-01

On the basis of large scale field hydrogeological investigation, synthetic hydrogeological studies related to groundwater system characteristics, permeability of rock bodies, groundwater dynamic, hydrogeochemistry, isotopic hydrology, CFC's of groundwater and groundwater flow field simulation were carried out for Beishan area, Gansu province. According to analysis on a large amount of hydrogeological data, the characteristics of groundwater circulation, groundwater hydrodynamics and hydrgeochemistry were described and the suitability of Beishan area as the potential area of high-level radioactive waste disposal was evaluated in the paper. Through this study, the hydrogeological study and evaluation methods in the siting of China's high level radioactive waste repository were set up. Furthermore, the important hydrogeological scientific evidence was provided for optimal site filtration of China's high-level radioactive waste repository in Beishan area. (authors)

Joint Russian-American hydrogeological-geochemical studies of the Karachai-Mishelyak system, South Urals, Russia

International Nuclear Information System (INIS)

Drozhko, E.G.; Glagolenko, Y.U.; Mokrov, Y.G.; Postovalova, G.A.; Samsonova, L.M.; Glagolev, A.V.; Ter-Saakian, S.A.; Glinsky, M.L.; Vasil'kova, N.A.; Skokov, A.V.; Wollenberg, H.A.; Tsan, C.F.; Frangos, W.; Solbau, R.D.; Stevenson, K.A.

1997-01-01

In September 1994, a Russian-American team conducted hydrogeological, geochemical, geophysical, and radiometric measurements in the teritory of the Mayak Production Association, Russia. The primary purpose of these operations was to examine the frontal area of a radioelement- and nitrate-laden groundwater plume moving from the disposal site, Lake Karachai, toward the Mishelyak River. Activities encompassed (1) isolation of hydrologic intervgals in two wells and production of water from these intervals, to comapre isolated versus open-well sampling methods and to determine hydraulic transmissivities of the aquifer(s); (2) surface and soil-water sampling, accompanying radiometric measurements and subsequent chemical analyses; and (3) electrical resistivity profiling in areas of expected contrasting resistivity. Preliminary results indicate that (1) 60 Co, 137 Cs, and 90 Sr are present in small concentrations (∝0.1% of permissible levels) in water of the Mishelyak River; (2) analyses of water samples collected by a downhole sampler and of water produced from packed-off intevals agree within limits of laboratory accuracy, attesting to the efficacy of the sampling methods presently used by the Russian workers; (3) considerable differences in contaminant concentrations exist between nearby wells, supporting the concept that the plume from Lake Karachai toward the Mishelyak River is controlled by steeply dipping fractures and shear zones; and (4) strong contrasts occur between the electrical resistivities of soil and bedrock. (orig./SR)

Hydrogeological research at the site of the Asse salt mine

International Nuclear Information System (INIS)

Batsche, H.; Rauert, W.; Klarr, K.

1980-01-01

In connection with the storage of radioactive wastes in the abandoned Asse salt mine near Brunswick (Federal Republic of Germany), the hydrogeology of the ridge of hills of Asse has been investigated. In order to obtain as detailed information as possible on the hydrogeological conditions, a long-term investigation programme has been set up and many methods of investigation have been used. Hydrogeological boring operations resulted in important scientific findings regarding, for example, the course of the salt table and the main anhydrite which towers up above the salt table into the overlying collapsed rocks. Hydrochemical data showed the hydraulic effect of transverse faults. Isotopic hydrological measurements permitted distinction between the flow behaviour of the groundwater in different aquifers. The origin of the salt springs at the northwest end of the structure can be explained. Some additional pumping and labelling tests are expected to yield quantitative results concerning hydraulic interrelationships recognized to date. The very complex hydrogeological structure of the ridge of hills of Asse is the result of the multiple succession of permeable and impermeable layers on the flanks of the structure, and, furthermore, is possibly due to the fact that in some individual faults groundwater may seep through normally impermeable layers as well as via waterways at the salt table. (author)

Stress variations during a glacial cycle at 500 m depth in Forsmark and Oskarshamn: Earth model effects

Energy Technology Data Exchange (ETDEWEB)

Lund, Bjoern [Uppsala Univ. (Sweden). Dept. of Earth Sciences

2006-06-15

This study has considered the response to a glaciation of Earth models of increasingly complex structure in elastic parameters and viscosity. The models are one-dimensional in the sense that they vary only in the depth direction, i.e. there are only uniform, horizontal layers in the models. I find that as the complexity of the models increase, and the properties of the uppermost kilometer of the Earth become less affected by average properties from deeper down, the flexural stresses at 500 m depth decrease, as expected. A lower Young's modulus, lower compressibility and lower density in the uppermost layer all act to lower the stresses. However, the three properties act differently on the resulting response. Introducing layering in Young's modulus generally decreases the stresses all along a profile through the ice model. Going from incompressible to compressible models affect the stresses outside the ice edge significantly more than the stresses under the ice sheet. Introducing layering in density conversely affect the stresses under the ice sheet more than those outside the ice edge. The combined effects of the most complex models tested here show that the glacially induced horizontal stresses at 500 m depth decrease to levels very similar in magnitude to the loading stress. There are, however, temporal variations in these horizontal stresses that do not follow the loading stress and which induce tensional or compressional horizontal stresses that persist when no ice is present.As is well known, changes in viscosity structure has a very large effect on the Earth response. Viscosity affect both the magnitudes of the induced stresses and the temporal behavior of the stress evolution. This is confirmed in the current study.The glacially induced stresses for some of the models have been used in combination with the current background stress field at Forsmark and Oskarshamn, as estimated in SKB's site models, to evaluate fault stability throughout a

Stress variations during a glacial cycle at 500 m depth in Forsmark and Oskarshamn: Earth model effects

International Nuclear Information System (INIS)

Lund, Bjoern

2006-06-01

This study has considered the response to a glaciation of Earth models of increasingly complex structure in elastic parameters and viscosity. The models are one-dimensional in the sense that they vary only in the depth direction, i.e. there are only uniform, horizontal layers in the models. I find that as the complexity of the models increase, and the properties of the uppermost kilometer of the Earth become less affected by average properties from deeper down, the flexural stresses at 500 m depth decrease, as expected. A lower Young's modulus, lower compressibility and lower density in the uppermost layer all act to lower the stresses. However, the three properties act differently on the resulting response. Introducing layering in Young's modulus generally decreases the stresses all along a profile through the ice model. Going from incompressible to compressible models affect the stresses outside the ice edge significantly more than the stresses under the ice sheet. Introducing layering in density conversely affect the stresses under the ice sheet more than those outside the ice edge. The combined effects of the most complex models tested here show that the glacially induced horizontal stresses at 500 m depth decrease to levels very similar in magnitude to the loading stress. There are, however, temporal variations in these horizontal stresses that do not follow the loading stress and which induce tensional or compressional horizontal stresses that persist when no ice is present.As is well known, changes in viscosity structure has a very large effect on the Earth response. Viscosity affect both the magnitudes of the induced stresses and the temporal behavior of the stress evolution. This is confirmed in the current study.The glacially induced stresses for some of the models have been used in combination with the current background stress field at Forsmark and Oskarshamn, as estimated in SKB's site models, to evaluate fault stability throughout a glacial cycle. The

An ice flow modeling perspective on bedrock adjustment patterns of the Greenland ice sheet

Directory of Open Access Journals (Sweden)

M. Olaizola

2012-11-01

Full Text Available Since the launch in 2002 of the Gravity Recovery and Climate Experiment (GRACE satellites, several estimates of the mass balance of the Greenland ice sheet (GrIS have been produced. To obtain ice mass changes, the GRACE data need to be corrected for the effect of deformation changes of the Earth's crust. Recently, a new method has been proposed where ice mass changes and bedrock changes are simultaneously solved. Results show bedrock subsidence over almost the entirety of Greenland in combination with ice mass loss which is only half of the currently standing estimates. This subsidence can be an elastic response, but it may however also be a delayed response to past changes. In this study we test whether these subsidence patterns are consistent with ice dynamical modeling results. We use a 3-D ice sheet–bedrock model with a surface mass balance forcing based on a mass balance gradient approach to study the pattern and magnitude of bedrock changes in Greenland. Different mass balance forcings are used. Simulations since the Last Glacial Maximum yield a bedrock delay with respect to the mass balance forcing of nearly 3000 yr and an average uplift at present of 0.3 mm yr⁻¹. The spatial pattern of bedrock changes shows a small central subsidence as well as more intense uplift in the south. These results are not compatible with the gravity based reconstructions showing a subsidence with a maximum in central Greenland, thereby questioning whether the claim of halving of the ice mass change is justified.

Bedrock Geologic Map of Vermont - Faults and Contacts

Data.gov (United States)

Vermont Center for Geographic Information — The bedrock geology was last mapped at a statewide scale 50 years ago at a scale of 1:250,000 (Doll and others, 1961). The 1961 map was compiled from 1:62,500-scale...

Bedrock Geologic Map of Vermont - Geochronology Sample Locations

Data.gov (United States)

Vermont Center for Geographic Information — The bedrock geology was last mapped at a statewide scale 50 years ago at a scale of 1:250,000 (Doll and others, 1961). The 1961 map was compiled from 1:62,500-scale...

The occurrence of waterfowl in the biotest basin at the Forsmark nuclear power plant, Sweden, 1981-1984

International Nuclear Information System (INIS)

Sandstroem, U.

1985-01-01

During the period Sep 1981 to Aug 1984 a monthly census was taken of waterfowl in the Biotest basin and its surroundings at Forsmark, as well as in a reference area in the region. During the same period the staff of the Biotest basin made weekly censuses of the basin. The aim of the censuses was to establish if there was any increase in the number of waterfowl in the Biotest basin and its surroundings caused by the discharge of cooling water from the two nuclear power reactors that are in operation in Forsmark. Seventeen waterfowl species were observed in the area during the period studied. Of these species five were regularly observed viz.: the Mute Swan (Cygnus olor), the Mallard (Anas plathyryncos), the Tufted Duck (Aythya fuligula), the Goldeneye (Bucephala clangula) and the Goosander (Mergus merganser). The first four species were generally found in low numbers in the Biotest basin and its surroundings, as well as in the reference area. This implies that the Biotest basin and its surroundings has not become an area of importance during the winter for waterfowl, with one exception: the Goosander. The Goosander showed an increasing population growth in the Biotest basin and its surroundings during the studied period with a maximum average in in the basin during the last winter. As a result, the size of the Goosander population may affect the number of small fish in the Biotest basin. (author)

Updated model for radionuclide transport in the near-surface till at Forsmark - Implementation of decay chains and sensitivity analyses

Energy Technology Data Exchange (ETDEWEB)

Pique, Angels; Pekala, Marek; Molinero, Jorge; Duro, Lara; Trinchero, Paolo; Vries, Luis Manuel de [Amphos 21 Consulting S.L., Barcelona (Spain)

2013-02-15

The Forsmark area has been proposed for potential siting of a deep underground (geological) repository for radioactive waste in Sweden. Safety assessment of the repository requires radionuclide transport from the disposal depth to recipients at the surface to be studied quantitatively. The near-surface quaternary deposits at Forsmark are considered a pathway for potential discharge of radioactivity from the underground facility to the biosphere, thus radionuclide transport in this system has been extensively investigated over the last years. The most recent work of Pique and co-workers (reported in SKB report R-10-30) demonstrated that in case of release of radioactivity the near-surface sedimentary system at Forsmark would act as an important geochemical barrier, retarding the transport of reactive radionuclides through a combination of retention processes. In this report the conceptual model of radionuclide transport in the quaternary till at Forsmark has been updated, by considering recent revisions regarding the near-surface lithology. In addition, the impact of important conceptual assumptions made in the model has been evaluated through a series of deterministic and probabilistic (Monte Carlo) sensitivity calculations. The sensitivity study focused on the following effects: 1. Radioactive decay of {sup 135}Cs, {sup 59}Ni, {sup 230}Th and {sup 226}Ra and effects on their transport. 2. Variability in key geochemical parameters, such as the composition of the deep groundwater, availability of sorbing materials in the till, and mineral equilibria. 3. Variability in hydraulic parameters, such as the definition of hydraulic boundaries, and values of hydraulic conductivity, dispersivity and the deep groundwater inflow rate. The overarching conclusion from this study is that the current implementation of the model is robust (the model is largely insensitive to variations in the parameters within the studied ranges) and conservative (the Base Case calculations have a

Hydrogeological investigation for sitting disposal repository for high level radioactive waste

International Nuclear Information System (INIS)

Guo Yonghai; Liu Shufen; Lv Chuanhe

2005-01-01

Based on the research experiences of our country and some developed countries in the world, the purpose, process and methods, as well as the function of hydrogeological investigation for sitting disposal repository for high radioactive waste are discussed. Meanwhile, the topic related to the acquisition of hydrogeological parameters is described as well, aiming at providing reference for the future study. (authors)

Input and turnover of forest tree litter in the Forsmark and Oskarshamn areas

Energy Technology Data Exchange (ETDEWEB)

Mjoefors, Kristina; Johansson, Maj-Britt; Nilsson, Aake [Dept. of Forest Soi ls, Swedish Univ. of Agricultural Sciences (Sweden); Hyvoenen, Riitta [Dept. of Eco logy, Swedish Univ. of Agricultural Sciences (Sweden)

2007-04-15

The site investigations reported here were conducted to provide data for the comprehensive descriptive ecosystem model that is being constructed. This report provides estimates of annual inputs of aboveground litter from trees (dry mass and amounts of C and N), litter decomposition rates and changes in organic and inorganic components in litter during decomposition. The study in the Forsmark area comprised two Norway spruce (Picea abies (L.) Karst) stands (sites F1 and F3), and a mixed stand of Norway spruce and alder (Alnus glutinosa (L.) Gaertn.) (site F2). The study in the Oskarshamn area comprised one common oak stand (Quercus robur L.) (site O1), one Scots pine stand (Pinus silvestris L.) (site O2) and one Norway spruce stand (site O3). In the Forsmark area, the aboveground litterfall from trees was of similar magnitude at sites F1 and F2, but considerably lower at site F3. At the former sites the average annual litterfall amounted to 195 and 231 gdw/m{sup 2} respectively, whereas the latter site received only 136 gdw/m{sup 2}. There was also a large variation in annual litterfall between stands in the Oskarshamn area. The spruce stand at site O3 exhibited the highest litterfall (almost 400 gdw/m{sup 2}), followed by the oak stand at site O1 (with almost 300 gdw/m{sup 2}), whereas the pine stand at site O2 had the lowest (less than 150 gdw/m{sup 2}). The proportion of needles/leaves in the total litterfall varied between 65% and 75% for the stands. The amount of carbon (C) returned in aboveground litterfall amounted to between 60 and 110 gdw/m{sup 2}/yr at the forest sites within the Forsmark area. The corresponding range for the sites in the Oskarshamn area was 70 to 190 gdw/m{sup 2}/yr. At sites O1 and O2 in Oskarshamn, about 3.6 gdw/m{sup 2}/yr of nitrogen (N) were returned annually to the forest floor by the aboveground litterfall. This was over four times the N amount deposited in the Scots pine stand in the same area (about 0.8 gdw/m{sup 2}/yr). At the

Input and turnover of forest tree litter in the Forsmark and Oskarshamn areas

International Nuclear Information System (INIS)

Mjoefors, Kristina; Johansson, Maj-Britt; Nilsson, Aake; Hyvoenen, Riitta

2007-04-01

The site investigations reported here were conducted to provide data for the comprehensive descriptive ecosystem model that is being constructed. This report provides estimates of annual inputs of aboveground litter from trees (dry mass and amounts of C and N), litter decomposition rates and changes in organic and inorganic components in litter during decomposition. The study in the Forsmark area comprised two Norway spruce (Picea abies (L.) Karst) stands (sites F1 and F3), and a mixed stand of Norway spruce and alder (Alnus glutinosa (L.) Gaertn.) (site F2). The study in the Oskarshamn area comprised one common oak stand (Quercus robur L.) (site O1), one Scots pine stand (Pinus silvestris L.) (site O2) and one Norway spruce stand (site O3). In the Forsmark area, the aboveground litterfall from trees was of similar magnitude at sites F1 and F2, but considerably lower at site F3. At the former sites the average annual litterfall amounted to 195 and 231 gdw/m 2 respectively, whereas the latter site received only 136 gdw/m 2 . There was also a large variation in annual litterfall between stands in the Oskarshamn area. The spruce stand at site O3 exhibited the highest litterfall (almost 400 gdw/m 2 ), followed by the oak stand at site O1 (with almost 300 gdw/m 2 ), whereas the pine stand at site O2 had the lowest (less than 150 gdw/m 2 ). The proportion of needles/leaves in the total litterfall varied between 65% and 75% for the stands. The amount of carbon (C) returned in aboveground litterfall amounted to between 60 and 110 gdw/m 2 /yr at the forest sites within the Forsmark area. The corresponding range for the sites in the Oskarshamn area was 70 to 190 gdw/m 2 /yr. At sites O1 and O2 in Oskarshamn, about 3.6 gdw/m 2 /yr of nitrogen (N) were returned annually to the forest floor by the aboveground litterfall. This was over four times the N amount deposited in the Scots pine stand in the same area (about 0.8 gdw/m 2 /yr). At the Forsmark sites, the N return in

Litho-stratigraphic and Hydrogeological Evaluation of Groundwater ...

African Journals Online (AJOL)

ADOWIE PERE

2015-10-30

://www.ajol.info/index.php/jasem http://www.bioline.org.br/ja. Litho-stratigraphic and Hydrogeological Evaluation of Groundwater System in Parts of. Benin Metropolis, Benin City Nigeria: The Key to Groundwater Sustainability.

Contribution to optimisation of Environmental Isotopes tracing in Hydrogeology. Case study of Madagascar

International Nuclear Information System (INIS)

RAJAOBELISON, J.

2003-01-01

The aim of this work is to suggest some improvements on the theory of interpretation and on the methodological approach for the optimum use of environmental isotopes tracing applied to hydrogeological investigation. A review of the theory of environmental isotopes used in hydrogeology has been made. The main constraints have been highlighted and led to some comments and proposals of improvement, in particular with regard to the continental effect on stable isotopes, to the seasonal variation of groundwater 1 4C content, and to the appropriate model for fractured crystalline aquifers. A literature survey on ten specific scientific papers, dealing with isotopic hydrology in miscellaneous types of aquifers and catchments, allowed to draw a synthesis of the hydrogeological, geochemical and isotopic constraints. A proposal of optimum methodological approach, taking into account the above mentioned constraints, have been inferred. The results of an on-going hydrogeological investigation carried out in the Southern crystalline basement and coastal sedimentary aquifers of Madagascar highlights an unusual methodological approach based on the lack of initial basic hydrogeological data. Besides, it shows to what extent the experience of the above mentioned research works can apply in the specific case of the complex aquifers of Madagascar. The lessons gained from this study contribute to enrich the synthesis of environmental isotopes constraints in hydrogeology and lead to a more realistic methodological approach proposal wich is likely to better make profitable the isotope hydrology technology

The make up of crystalline bedrock - crystalline body and blocks