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Sample records for hydrogeochemical studies sdm-site

  1. 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

  2. Geology Laxemar. Site descriptive modelling SDM-Site Laxemar

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    Wahlgren, Carl-Henric (Geological Survey of Sweden, Uppsala (Sweden)); Curtis, Philip; Hermanson, Jan; Forssberg, Ola; Oehman, Johan (Golder Associates AB (Sweden)); Fox, Aaron; La Pointe, Paul (Golder Associates Inc (United States)); Drake, Henrik (Dept. of Earth Sciences, Univ. of Goeteborg, Goeteborg (Sweden)); Triumf, Carl-Axel; Mattsson, Haakan; Thunehed, Hans (GeoVista AB, Luleaa (Sweden)); Juhlin, Christopher (Dept. of Earth Sciences, Uppsala Univ., Uppsala (Sweden))

    2008-11-15

    The geological work during the SDM Site Laxemar modelling stage has involved the continued development of deterministic models for rock domains (RSM) and deformation zones (ZSM), the identification and deterministic modelling of fracture domains (FSM), and the development of statistical models for fractures and minor deformation zones (geological discrete fracture network (DFN) modelling). The geological DFN model addresses fractures/structures with a size of less than 1 km, which is the lower cut-off of structures included in the deterministic modelling of deformation zones. In order to take account of variability in data resolution, deterministic models for rock domains and deformation zones are presented in both regional and local scale model volumes, while the geological DFN model is valid only within specific fracture domains inside the Laxemar local model volume. The geological and geophysical data that constitute the basis for the SDM-Site Laxemar modelling work comprise all data that have been acquired from Laxemar, i.e. all data that were available at the data freeze for SDM-Site Laxemar at August 31, 2007. Selected quality controlled data from the complementary cored borehole KLX27A have also been utilised in the modelling work. Data from the following investigations were acquired during the complete site investigation between the data freezes for Laxemar 1.2 and SDM-Site Laxemar as defined above: A revised bedrock geological map at the ground surface. Geological and geophysical data from 40 new cored boreholes and 14 percussion boreholes. Sampling and subsequent modal and geochemical analytical work of bedrock samples taken in connection with excavations in southern Laxemar. Detailed mapping of fractures and rock units along 10 trench excavations and 2 large surface exposures (drill sites for KLX09 and KLX11A/KLX20A). Special studies involving more detailed characterisation of deformation zones identified in the geological single-hole interpretation

  3. Confidence assessment. Site descriptive modelling SDM-Site Forsmark

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    2008-09-15

    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

  4. Bedrock hydrogeology Forsmark. Site descriptive modelling, SDM-Site Forsmark

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    Follin, Sven (SF GeoLogic AB, Taeby (Sweden))

    2008-12-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) has conducted site investigations at two different locations, the Forsmark and Laxemar-Simpevarp areas, with the objective of siting a final repository for spent nuclear fuel according to the KBS-3 concept. Site characterisation should provide all data required for an integrated evaluation of the suitability of the investigated site and an important component in the characterisation work is the development of a hydrogeological model. The hydrogeological model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It also provides input to the safety assessment. Another important use of the hydrogeological model is in the environmental impact assessment. This report presents the understanding of the hydrogeological conditions of the bedrock at Forsmark reached following the completion of the surface-based investigations and provides a summary of the bedrock hydrogeological model and the underlying data supporting its development. It constitutes the main reference on bedrock hydrogeology for the site descriptive model concluding the surface-based investigations at Forsmark, SDM-site, and is intended to describe the hydraulic properties and hydrogeological conditions of the bedrock at the site and to give the information essential for demonstrating understanding

  5. Bedrock hydrogeochemistry Forsmark. Site descriptive modelling SDM-Site Forsmark

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    Laaksoharju, Marcus (Geopoint AB, Sollentuna (Sweden)); Smellie, John (Conterra AB, Partille (Sweden)); Tullborg, Eva-Lena (Terralogica, Graabo (Sweden)); Gimeno, Maria (Univ. of Zaragoza, Zaragoza (Spain)); Hallbeck, Lotta (Microbial Analytics, Goeteborg (Sweden)); Molinero, Jorge (Amphos XXI Consulting S.L., Barcelona (Spain)); Waber, Nick (Univ. of Bern, Bern (Switzerland))

    2008-12-15

    The overall objectives of the hydrogeochemical site description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site, and to use this understanding to develop models that address 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 porewater and their evolution with time. The specific aims of the hydrogeochemical work were: To document the hydrogeochemistry at the Forsmark site with focus on the development of conceptual models to describe and visualise the site. To provide relevant parameter values to be used for safety assessment calculations. To provide the hydrogeochemical basis for the modelling work by other teams, in particular hydrogeology. To take account of the feedback from the SR-Can safety assessment work that bears relevance to the hydrogeochemical modelling work. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. In this report, the groundwaters have been interpreted in relation to their origin, evolution and composition, which require close integration with geological, climatological and hydrogeological information. Past climate changes are one of the major driving forces for long-term hydrogeochemical changes (hundreds to thousands of years) and are, therefore, of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the Fennoscandian crystalline bedrock. In contrast, redox buffer capacity of the bedrock will minimise the effects on changes in alkalinity and redox at repository depths, therefore limiting the variations in pH and Eh significantly, regardless of major changes in groundwater composition. There is

  6. Confidence assessment. Site-descriptive modelling SDM-Site Laxemar

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    2008-12-15

    The objective of this report is to assess the confidence that can be placed in the Laxemar site descriptive model, based on the information available at the conclusion of the surface-based investigations (SDM-Site Laxemar). 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. Procedures for this assessment have been progressively refined during the course of the site descriptive modelling, and applied to all previous versions of the Forsmark and Laxemar site descriptive models. They include assessment of whether all relevant data have been considered and understood, identification of the main uncertainties and their causes, possible alternative models and their handling, and consistency between disciplines. The assessment then forms the basis for an overall confidence statement. The confidence in the Laxemar site descriptive model, based on the data available at the conclusion of the surface based site investigations, has been assessed by exploring: - Confidence in the site characterization data base, - remaining issues and their handling, - handling of alternatives, - consistency between disciplines and - main reasons for confidence and lack of confidence in the model. Generally, the site investigation database is of high quality, as assured by the quality procedures applied. It is judged that the Laxemar site descriptive model has an overall high level of confidence. Because of the relatively robust geological model that describes the site, the overall confidence in the Laxemar Site Descriptive model is judged to be high, even though details of the spatial variability remain unknown. The overall reason for this confidence is the wide spatial distribution of the data and the consistency between

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

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

    2009-01-15

    , hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on available primary data from the extended data freeze L2.3 at Laxemar (November 30 2007). The data interpretation was carried out during November 2007 to September 2008. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. The original works by the ChemNet modellers are presented in four level III reports containing complementary information for the bedrock hydrogeochemistry Laxemar Site Descriptive Model (SDM-Site Laxemar, R-08-93) level II report. There is also a fifth level III report: Fracture mineralogy of the Laxemar area (R-08-99). This report presents the modelling work performed by the UZ (Univ. of Zaragoza) group as part of the work plan for Laxemar-Simpevarp 2.2 and 2.3. The main processes determining the global geochemical evolution of the Laxemar-Simpevarp groundwaters system are mixing and reaction processes. Mixing has taken place between different types of waters (end members) over time, making the discrimination of the main influences not always straightforward. Several lines of evidence suggest the input of dilute waters (cold or warm), at different stages, into a bedrock with pre-existing very saline groundwaters. Subsequently, marine water entered the system over the Littorina period (when the topography and the distance to the coast allowed it) and mixed with pre-existent groundwaters of variable salinity. In the Laxemar subarea mainland, the Littorina input occurred only locally and it has mostly been flushed out by the subsequent input of warm meteoric waters with a distinctive modern isotopic signature. In addition to mixing processes and superimposed to their

  8. Emplacement mechanisms and structural influences of a younger granite intrusion into older wall rocks - a principal study with application to the Goetemar and Uthammar granites. Site-descriptive modelling SDM-Site Laxemar

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    Cruden, Alexander R. (Dept. of Geology, Univ. of Toronto (Canada))

    2008-12-15

    The c. 1.80 Ga old bedrock in the Laxemar-Simpevarp area, which is the focus of the site investigation at Oskarshamn, is dominated by intrusive rocks belonging to the c. 1.86-1.65 Ga Transscandinavian Igneous Belt (TIB). However, the site investigation area is situated in between two c. 1.45 Ga old anorogenic granites, the Goetemar granite in the north and the Uthammar granite in the south. This study evaluates the emplacement mechanism of these intrusions and their structural influence on the older bedrock. Field observations and structural measurements indicate that both the Goetemar and the Uthammar granites are discordant and have not imposed any significant ductile deformation on their wall-rocks. The apparent conformity of geological contacts and fabrics in the wall rocks and the southern margin of the Goetemar granite is coincidental and inherited from the pattern of Svecokarelian deformation of the TIB. However, interpretation of regional aeromagnetic data suggests that the granites occur within a broad, NNE-SSW trending linear belt, pointing to deep seated tectonic control on their generation, ascent and emplacement. Thermochronology indicates that the granites were emplaced at depths between 4 and 8 km into brittle wall rocks. The 3-D shape of the Goetemar and Uthammar plutons has been investigated by 2.75D forward modelling of the residual gravity anomalies due to both granites. Both granites are associated with strong residual gravity anomalies of up to -10 mgal. Constraints on the geometry of the plutons at the surface are provided from surface geology maps and several deep boreholes located on or close to the model profiles. A further variable in the gravity modelling is introduced by either allowing the upper contact of the plutons to assume the most suitable orientation to produce the best fit between the modelled and observed gravity ('unconstrained models') or by forcing the near surface orientation of the contacts to be vertical (&apos

  9. Fracture mineralogy of the Forsmark site. SDM-Site Forsmark

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    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

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

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    2009-12-15

    The Swedish Nuclear Fuel and Waste Management Company (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 SDM 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 of 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 Laxemar, presents an integrated understanding of the Laxemar-Simpevarp area (with special emphasis on the Laxemar subarea) at the completion of the surface-based investigations, which were conducted during the period 2002 to 2007. A summary is also provided 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 of the data analyses and modelling of the different disciplines. The Laxemar-Simpevarp area is located in the province of Smaaland within the municipality of Oskarshamn, about 230 km south of Stockholm. The candidate area for site investigation is located along the shoreline of the strait of Kalmarsund, within a 1.8 billion year old suite of well preserved bedrock belonging to the Transscandinavian Igneous Belt formed during

  11. 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

  12. Compilation of data used for the analysis of the geological and hydrogeological DFN models. Site descriptive modelling SDM-Site Laxemar

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    Hermanson, Jan; Fox, Aaron; Oehman, Johan (Golder Associates (Sweden)); Rhen, Ingvar (SWECO (Sweden))

    2008-08-15

    This report provides an overview and compilation of the various data that constitutes the basis for construction of the geological and hydrogeological discrete feature network (DFN) models as part of model version SDM-Site Laxemar. This includes a review of fracture data in boreholes and in outcrop. Furthermore, the basis for the construction of lineament maps is given as well as a review of the hydraulic test data from cored and percussion-drilled boreholes. An emphasis is put on graphical representation of borehole logs in the form of composites of geological, hydrogeological and even hydrogeochemical data in the case of cored boreholes. One major contribution is a compilation of characteristics of minor local deformation zones (MDZs) identified in cored boreholes. Basic orientation data and fracture intensity data are presented as a function of depth for individual boreholes. The coupling between hydrogeological data and geological data is further refined in plots of Posiva flow log (PFL) data vs. geological single hole interpretation data

  13. Geological discrete fracture network model for the Laxemar site. Site Descriptive Modelling. SDM-Site Laxemar

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    La Pointe, Paul; Fox, Aaron (Golder Associates Inc (United States)); Hermanson, Jan; Oehman, Johan (Golder Associates AB, Stockholm (Sweden))

    2008-12-15

    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 modelling team in the production of the SDM-Site Laxemar geological discrete-fracture network (DFN) model. The DFN builds upon the work of other geological models, including the deformation zone and rock domain models. The geological DFN is a statistical model for stochastically simulating rock fractures and minor deformation zones at a scale of less than 1,000 m (the lower cut-off of the DZ models). The geological DFN is valid within six distinct fracture domains inside the Laxemar local model subarea: FSM{sub C}, FSM{sub E}W007, FSM{sub N}, FSM{sub N}E005, FSM{sub S}, and FSM{sub W}. The models are built using data from detailed surface outcrop maps, geophysical lineament maps, and the cored borehole record at Laxemar. The conceptual model for the SDM-Site Laxemar geological DFN model revolves around the identification of fracture domains based on relative fracture set intensities, orientation clustering, and the regional tectonic framework (including deformation zones). A single coupled fracture size/fracture intensity concept (the Base Model) based on a Pareto (power-law) distribution for fracture sizes was chosen as the recommended parameterisation. A slew of alternative size-intensity models were also carried through the fracture analyses and into the uncertainty and model verification analyses. Uncertainty is modelled by analysing the effects on fracture intensity (P32) that alternative model cases can have. Uncertainty is parameterised as a ratio between the P32 of the

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

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    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

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

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    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

  16. Explorative analysis of microbes, colloids and gases together with microbial modelling. Site description model SDM-Site Laxemar

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    Hallbeck, Lotta; Pedersen, Karsten (Microbial Analytics Sweden AB, Goeteborg (Sweden))

    2008-08-15

    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 the major driving force 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, 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 Laxemar site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and Univ. researchers with expertise in geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on available primary data from the extended data freeze L2.3 (Nov 2007). This report focuses on microbiology, colloids and gases. Several methods must be used to characterise active microbial communities in groundwater. Microbial parameters of interest are the total number of cells (TNC) and the presence of various metabolic groups of

  17. Hydrogeochemical and spectroscopic studies of radioactive materials in Ayrakan and Cheshmeh Shotori areas, northeastern Isfahan province

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    Mostafa Esmaeili Vardanjani

    2011-11-01

    Full Text Available Groundwaters hydrochemistry of Ayrakan and Cheshmeh Shotori areas and geochemistry of rare earth elements, indicate Ayrakan alkali granite as the origin of uranium and other dissolved elements in groundwaters of these areas. Geochemical and hydrogeochemical studies as well as the trend of uranium and thorium transition and mobility in aqueous environments of these areas indicate uranium adsorption by iron hydroxide (goethite as the deterrent agent against uranium transition and mobility from depth to surface. Gamma-ray spectroscopic study of sediments from Cheshmeh Shotori area by HPGe detector indicates the presence of 226Ra in high contents and as the radioactive nuclide that is the reason for high activity of these sediments. Production of 226Ra from 238U decay, shorter half-life of 226Ra compared to 238U, radium transition by groundwaters from depth to surface as well as hydrogeochemical evidences, all suggest the possibility of existence of hidden uranium deposit and uranium mineralization in depth and the distance between Ayrakan and Cheshmeh Shotori areas.

  18. Hydrogeochemical quality and suitability studies of groundwater in northern Bangladesh.

    Science.gov (United States)

    Islam, M J; Hakim, M A; Hanafi, M M; Juraimi, Abdul Shukor; Aktar, Sharmin; Siddiqa, Aysha; Rahman, A K M Shajedur; Islam, M Atikul; Halim, M A

    2014-07-01

    Agriculture, rapid urbanization and geochemical processes have direct or indirect effects on the chemical composition of groundwater and aquifer geochemistry. Hydro-chemical investigations, which are significant for assessment of water quality, were carried out to study the sources of dissolved ions in groundwater of Dinajpur district, northern Bangladesh. The groundwater samplish were analyzed for physico-chemical properties like pH, electrical conductance, hardness, alkalinity, total dissolved solids and Ca2+, Mg2+, Na+, K+, CO3(2-), HCO3(-), SO4(2-) and Cl- ions, respectively. Based on the analyses, certain parameters like sodium adsorption ratio, soluble sodium percentage, potential salinity, residual sodium carbonate, Kelly's ratio, permeability index and Gibbs ratio were also calculated. The results showed that the groundwater of study area was fresh, slightly acidic (pH 5.3-6.4) and low in TDS (35-275 mg I(-1)). Ground water of the study area was found suitable for irrigation, drinking and domestic purposes, since most of the parameters analyzed were within the WHO recommended values for drinking water. High concentration of NO3- and Cl- was reported in areas with extensive agriculture and rapid urbanization. Ion-exchange, weathering, oxidation and dissolution of minerals were major geochemical processes governing the groundwater evolution in study area. Gibb's diagram showed that all the samples fell in the rock dominance field. Based on evaluation, it is clear that groundwater quality of the study area was suitable for both domestic and irrigation purposes.

  19. Validation of coastal oceanographic models at Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-12-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterization at two different locations, the Forsmark and the Laxemar-Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The characterization 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 and the coupled discrete basin (CDB-) model employed to simulate the water exchange in the near-shore coastal zone in the Laxemar-Simpevarp area, an encompassing measurement program entailing data from six stations (of which two are close) 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 Laxemar- Simpevarp study area at its interfacial boundary to the coarse resolution (CR-) model of the entire Baltic was reproduced. In addition to this, it is of particular interest how the time-varying density-determining properties, salinity and temperature, at the borders are propagated into the FR-domain and further influence the water exchange with the interior, more secluded, basins. An important part of the validation process has been to carefully evaluate which measurement data that can be considered reliable. The result was that some periods of foremost near-surface salinity data had to be discarded due to growth of algae on the conductivity sensors. Interference with ship traffic and lack of absolute calibration of the salinity meters necessitated dismissal of measurement data too. In this study so-called Mesan data have been consistently used for the meteorological forcing of the 3D-models. Relative the assessed data that can be accepted as adequate, the outcome of the

  20. 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

  1. Geological evolution, palaeoclimate and historical development of the Forsmark and Laxemar-Simpevarp areas. Site descriptive modelling SDM-Site

    Energy Technology Data Exchange (ETDEWEB)

    Soederbaeck, Bjoern (ed.)

    2008-06-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterization at two different locations, the Forsmark and Laxemar-Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The site investigations started in 2002 and were completed in 2007. The analysis and modelling of data from the site investigations, which have taken place during and after these investigations, provide a foundation for the development of an integrated, multidisciplinary site descriptive model (SDM) for each of the two sites. A site descriptive model constitutes a description of the site and its regional setting, covering the current state of the geosphere and the biosphere, as well as those natural processes that affect or have affected their long-term development. Hitherto, a number of reports presenting preliminary site descriptive models for Forsmark and Laxemar-Simpevarp have been published. In these reports, the evolutionary and historical aspects of the site were included in a separate chapter. The present report comprises a further elaboration of the evolutionary and historical information included in the preliminary SDM reports, but presented here in a separate, supplementary report to the final site description, SDM-Site. The report is common to the two investigated areas, and the overall objective is to describe the long-term geological evolution, the palaeoclimate, and the post-glacial development of ecosystems and of the human population at the two sites. The report largely consists of a synthesis of information derived from the scientific literature and other sources not related to the site investigations. However, considerable information from the site investigations that has contributed to our understanding of the past development at each site is also included. This unique synthesis of both published information in a regional perspective and new site-specific information breaks new ground in our understanding

  2. Description of surface hydrology and near-surface hydrogeology at Forsmark. Site descriptive modelling SDM. Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Per-Olof (Artesia Grundvattenkonsult AB, Taeby (Sweden))

    2008-12-15

    This report describes the modelling of the surface hydrology and near-surface hydrogeology that was performed for the final site descriptive model of Forsmark produced in the site investigation stage, SDM-Site Forsmark. The comprehensive investigation and monitoring programme forms a strong basis for the developed conceptual and descriptive model of the hydrological and near-surface hydrological system of the site investigation area. However, there are some remaining uncertainties regarding the interaction of deep and near-surface groundwater and surface water of importance for the understanding of the system: The groundwaters in till below Lake Eckarfjaerden, Lake Gaellbotraesket, Lake Fiskarfjaerden and Lake Bolundsfjaerden have high salinities. The hydrological and hydrochemical interpretations indicate that these waters are relict waters of mainly marine origin. From the perspective of the overall water balance, the water below the central parts of the lakes can be considered as stagnant. However, according to the hydrochemical interpretation, these waters also contain weak signatures of deep saline water. Rough chloride budget calculations for the Gaellbotraesket depression also raise the question of a possible upward flow of deep groundwater. No absolute conclusion can be drawn from the existing data analyses regarding the key question of whether there is a small ongoing upward flow of deep saline water. However, Lake Bolundsfjaerden is an exception where the clear downward flow gradient from the till to the bedrock excludes the possibility of an active deep saline source. The available data indicate that there are no discharge areas for flow systems involving deep bedrock groundwater in the northern part of the tectonic lens, where the repository is planned to be located (the so-called 'target area'). However, it can not be excluded that such discharge areas exist. Data indicate that the prevailing downward vertical flow gradients from the QD to

  3. Hydrogeochemical processes and geochemical modeling in a coastal aquifer: Case study of the Marathon coastal plain, Greece

    Science.gov (United States)

    Papazotos, Panagiotis; Koumantakis, Ioannis; Kallioras, Andreas; Vasileiou, Eleni; Perraki, Maria

    2017-04-01

    Determining the hydrogeochemical processes has always been a challenge for scientists. The aim of this work is the study of the principal hydrogeochemical processes controlling groundwater quality in the Marathon coastal plain, Greece, with emphasis on the origin of the solutes. Various physicochemical parameters and major ions of twenty-five groundwater samples were analyzed. The hydrogeochemical data of groundwater were studied in order to determine the major factors controlling the chemical composition and hydrogeochemical evolution. In the Marathon coastal plain, three different zones of the alluvial granular aquifer system have been detected, considering the geochemical processes and recharge, which affect its hydrochemical characteristics. The alluvial granular aquifer system is divided eastwards into three zones: a) the natural recharge zone, b) the reverse ion exchange zone and c) the diffusion sea water zone. Cl-is the dominant anion and Na+and Ca2+ are the dominant cations, as determined by plotting the analyses on the respective Piper diagram. Near the coastline high concentrations of Na+ and Cl- were observed indicating a zone of seawater intrusion. On the other hand, westward there is increasing concentration of HCO3- with simultaneous decrease of Na+is indication of a recharge zone from karstic aquifers of the study area. Between the aforementioned zones there is an intermediate one, where reverse ion exchange takes place due to high concentrations of dissolved Na+ and Ca2+ adsorption. The saturation indices (SI) were calculated using the geochemical modeling software PHREEQC. Mineral phases of halite, sylvite, gypsum and anhydrite were estimated to be undersaturated in the water samples, suggesting these phases are minor or absent in the host rock. On the other hand, calcite, aragonite and dolomite are close to equilibrium; these minerals are present in the host rocks or in the unsaturated zone, possibly increasing the Ca2+, Mg2+ and HCO3

  4. Earthquakes: hydrogeochemical precursors

    Science.gov (United States)

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  5. Hydrogeochemical and stream-sediment reconnaissance, orientation study, Ouachita Mountain area, Arkansas. National Uranium Resource Evaluation Program

    Energy Technology Data Exchange (ETDEWEB)

    Steele, K. F.

    1982-08-01

    A hydrogeochemical ground water orientation study was conducted in the multi-mineralized area of the Ouachita Mountains, Arkansas in order to evaluate the usefulness of ground water as a sampling medium for uranium exploration in similar areas. Ninety-three springs and nine wells were sampled in Clark, Garland, Hot Springs, Howard, Montgomery, Pike, Polk, and Sevier Counties. Manganese, barite, celestite, cinnabar, stibnite, copper, lead, and zinc are present. The following parameters were determined: pH, conductivity, alkalinity, U, Br, Cl, F, He, Mn, Na, V, Al, Dy, NO/sub 3/, NH/sub 3/, SO/sub 4/, and PO/sub 4/. The minerals appear to significantly affect the chemistry of the ground water. This report is issued in draft form, without detailed technical and copy editing. This was done to make the report available to the public before the end of the National Uranium Resource Evaluation.

  6. Hydrogeochemical processes and isotopes analysis. Study case: "La Línea Tunnel", Colombia

    Science.gov (United States)

    Piña, Adriana; Donado, Leonardo; Cramer, Thomas

    2017-04-01

    Hydrogeochemical and stable isotopes analyses have been widely used to identify recharge and discharge zones, flowpaths, type, origin and age of water, chemical processes between minerals and groundwater as well as effects caused by anthropogenic or natural pollution. In this paper we analyze the interactions between groundwater and surface water using as laboratory the tunnels located at the La Línea Massif in the Cordillera Central of the Colombian Andes. The massif is formed by two igneous-metamorphic fractured complexes (Cajamarca and Quebradagrande group) plus andesithic porphyry rocks from the tertiary period. There, eight main fault zones related to surface creeks were identified and main inflows inside the tunnels were reported. 60 water samples were collected in surface and inside the tunnel in fault zones in two different years, 2010 and 2015. To classify water samples, a multivariate statistical analysis combining Factor Analysis (FA) with Hierarchical Cluster Analysis (HCA) was performed. Then, analyses of the major chemical elements and water isotopes (18O, 2H and 3H) were used to define the origin of dissolved components and to analyse the evolution in time. Most samples were classified as bicarbonate calcite water or bicarbonate magnesium water type. Isotopic analyses show a characteristic behavior for east and west watershed and each geologic group. According to the FA and HCA, obtained factors and clusters are first related to the location of the samples (surface or tunnel samples) followed by the geology. Surface samples behave according to the Colombian meteoric line as inflows related to permeable faults while less permeable faults show hydrothermal processes. Finally, water evolution in time shows a decrease of pH, conductivity and Mg2+ related to silicate weathering or precipitation/dissolution processes that affect the spacing in fractures and consequently, the hydraulic properties.

  7. Hydrogeochemical and isotopic studies of groundwater in the middle voltaian aquifers of the Gushegu district of the Northern region

    Science.gov (United States)

    Salifu, Musah; Yidana, Sandow Mark; Anim-Gyampo, Maxwell; Appenteng, Michael; Saka, David; Aidoo, Felix; Gampson, Enoch; Sarfo, Mark

    2017-06-01

    This work is to establish the hydrochemistry and origin of groundwater in some parts of the Gushegu district of the Northern Region of Ghana. Hydrochemical data from 19 groundwater and 7 rock samples have been used to evaluate water quality, water types, and sources of various ions as well as origin of the groundwater. The study results show that the quality of groundwater from the area is generally not good due to their fluoride (F-), bicarbonate (HCO3 -) and electrical conductivity (EC) concentrations. The F- contents of the groundwater have values as high as 1.97 mg/L, with 53 % of the groundwater having concentrations of F- exceeding the WHO recommended allowable limits. These high F- values have the potential of causing serious health problems such as kidney failure, dental and skeletal fluorosis, reproductive problem and reduction in intelligent quotient of consumers. A plot of Gibbs diagram reveals that rock weathering and precipitation are the major hydrogeochemical processes regulating the water chemistry of the study area. Petrographic thin-section analyses of rock samples identify minerals present to be muscovite, plagioclase feldspars, quartz, sericite and iron oxide. Stable isotope (18O and 2H) composition of the waters reveals that most of the groundwater is likely to be recharged from local precipitation, indicating their meteoric origin. Some samples, however, showed considerable evaporation.

  8. Statistical and hydrogeochemical approach to study processes that affect groundwater composition in the Ferrara province (Italy)

    Science.gov (United States)

    Di roma, Antonella; Vaccaro, Carmela

    2017-04-01

    The ground water should not be seen only as a reserve for the water supply, but also be protected for its environmental value. Groundwater plays an essential role in the hydrological cycle for which the characterization, pollution prevention, monitoring and restoration are essential in view of the recovery and identification of the water bodies to be submitted to recharge for the adaptation to DM n. 100/2016. Groundwater of Ferrara province presents salinisation problems and pollution of noxious metals that can be mitigated through recharge processes evaluated based on the specific site characteristics. It is essential to know the hydrogeochemical characteristics of different aquifer levels. To do this have been discuss analytical results of groundwater (2014-2015 monitoring phreatic ground water and temporal series from 2003-2015 A1-A2-A3 samples from Emilia Romagna databases). Results showed that in the territory analyzed insist both salinization and refreshening processes. Factor analysis(FA) conducted on samples has divided them into three groups. 1: samples affected by ionic exchange, 2: pH reaction on heavy metal, 3: samples affected by mineralization. The geochemical groundwater facies changed from Ca-HCO3, and NaHCO3 with a small samples group of CaSO4 and through geochemical investigations were observed the reactions that take place in the waters mixing of different composition. The Na excesses are explained by ionic exchange processes. A determinant role is played by ionic exchange between Ca and Na. In this territory is important also the role of CH4 presence which typically rises towards the surface along faults and fractures and influence rise of deep water with different composition. On samples selected from FA Group 1 has been observed an increase of the CEC (Cation exchange capacity). Adsorption-desorption exchanges take place between water and the fine fraction sediment rich in clay minerals. Higher CEC values are found in rich organic substance

  9. Numerical modelling of surface hydrology and near-surface hydrogeology at Forsmark. Site descriptive modelling SDM. Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-09-15

    reduced in order to reach the observed accumulated discharge. 2. The uppermost layer of Quaternary deposits in Forsmark is very high-conductive. A drainage function was activated in the model to describe the fast transport of water in the upper soil layer to the water courses. 3. Anisotropy in the hydraulic conductivity of the till was applied in the model. 4. The model was extended to a depth of 600 m (from 150 m), where a no flow boundary condition was applied. When validating the model, the model was run for an independent data period. After the validation and evaluation of the model results, it was decided to run an additional sensitivity analysis, including simulations of a pumping test, in order to further investigate possible reasons for the high calculated heads in the bedrock and the problems related to the surface water discharge during the validation period. The results from the additional sensitivity analysis showed that the bedrock properties had to be modified to lower the calculated heads in the bedrock and to improve the agreement with the responses observed during the pumping test. The vertical conductivity was reduced by a factor of ten, and the horizontal conductivity of the sheet joints was increased by a factor of ten. The storage coefficient of the rock was reduced by several orders of magnitude to achieve fast responses similar to those observed in the pumping test. To reach a good agreement between measurements and the calculated heads in the bedrock an activation of the drainage at the SFR repository was needed. The final mean absolute error between observed and calculated groundwater elevation in the Quaternary deposits was 0.28 m, and the corresponding value for the bedrock was 0.41 m. The solute transport modelling presented in this report included particle tracking, PT, and advection-dispersion, AD, simulations. The studied particle and AD solute sources were placed in the bedrock as well as on the ground surface. When modelling transport from

  10. identification of hydrogeochemical processes in groundwater using ...

    African Journals Online (AJOL)

    PROF EKWUEME

    GROUNDWATER USING MAJOR ION CHEMISTRY: A CASE STUDY. OF YENAGOA ... chemistry of the groundwater and identify the dominant hydrogeochemical processes and mechanisms responsible for the evolution of ... from silicate weathering process which was also supported by higher HCO3 values. Reverse ion ...

  11. Hydrogeochemical assessment of groundwater in Kashmir Valley ...

    Indian Academy of Sciences (India)

    Ca–HCO3, Mg–HCO3, Ca–Mg–HCO3, Na–HCO3 were the dominant hydrogeochemical facies. High concentration of HCO3 and pH less than 8.8 clearly indicated that intense chemical weathering processes have taken place in the study area. The groundwater flow pattern in the area follows the local surface topography ...

  12. Hydrogeochemical analysis and quality evaluation of groundwater ...

    African Journals Online (AJOL)

    GREG

    2013-05-08

    May 8, 2013 ... hydrogeochemical parameters were evaluated, while techniques such as sodium absorption ratio. (SAR), sodium percent, residual sodium ... water chemistry also has a potential use for tracing the origins and the history of water as well ... are especially subject to this action. It is hoped that this study would ...

  13. Hydrogeochemical framework and factor analysis of fluoride ...

    African Journals Online (AJOL)

    Fluoride contamination of groundwater within the Savelugu-Nanton District was assessed using hydrogeochemical framework and multivariate statistical approach. Eighty-one (No) boreholes were sampled for quality assessment in May and June 2008. The main objective of this study was to assess the fluoride levels in ...

  14. Groundwater hydrogeochemical characteristics in rehabilitated coalmine spoils

    Science.gov (United States)

    Gomo, M.; Masemola, E.

    2016-04-01

    The investigation aims to identify and describe hydrogeochemical processes controlling the evolution of groundwater chemistry in rehabilitated coalmine spoils and their overall influence on groundwater quality at a study area located in the Karoo basin of South Africa. A good understanding of the processes that controls the evolution of the mine water quality is vital for the planning, application and management of post-mining remedial actions. The study utilises scatter plots, statistical analysis, PHREEQC hydrogeochemical modelling, stoichiometric reaction ratios analysis, and the expanded Durov diagram as complimentary tools to interpret the groundwater chemistry data collected from monitoring boreholes from 1995 to 2014. Measured pH ranging between 6-8 and arithmetic mean of 7.32 shows that the groundwater system is characterised by circumneutral hydrogeochemical conditions period. Comparison of measured groundwater ion concentrations to theoretical reaction stoichiometry identifies Dolomite-Acid Mine Drainage (AMD) neutralisation as the main hydrogeochemical process controlling the evolution of the groundwater chemistry. Hydrogeochemical modelling shows that, the groundwater has temporal variations of calcite and dolomite saturation indices characterised by alternating cycles of over-saturation and under-saturation that is driven by the release of sulphate, calcium and magnesium ions from the carbonate-AMD neutralization process. Arithmetic mean concentrations of sulphate, calcium and magnesium are in the order of 762 mg/L, 141 mg/L and 108 mg/L. Calcium and magnesium ions contribute to very hard groundwater quality conditions. Classification based on total dissolved solids (TDS), shows the circumneutral water is of poor to unacceptable quality for drinking purposes. Despite its ability to prevent AMD formation and leaching of metals, the dolomite-AMD neutralisation process can still lead to problems of elevated TDS and hardness which mines should be aware of

  15. Hydrogeochemical assessment of groundwater in Kashmir Valley ...

    Indian Academy of Sciences (India)

    Hydrogeochemical assessment of groundwater in Kashmir Valley, India. 1033. Figure 1. Geology of the study area and the location of sampling sites. 4. Results and discussion ..... 1036. G H Jeelani et al. F ig u re. 2 . Spa tia l v a ria tio n o f m a jo r io ns in g ro undw a ter a cro ss the a llu via l ba sin o f the. Ka sh mir. V a lley.

  16. Hydrogeochemical processes as environmental indicators in drip water: Study of the Cueva del Agua (Southern Spain

    Directory of Open Access Journals (Sweden)

    Francisco Sanchez-Martos

    2008-01-01

    Full Text Available Karst caves exhibit a wide range of hydrological and hydrochemical responses to infiltration events, due to their physical heterogeneity space and dynamic variability over time, and due to non-Gaussian inputs (rain and outputs (discharge. This paper reviews different approaches of studying seepage water in caves, in order to understand the infiltration regimen in the non-saturated zone of karst areas. As an illustration, we describe a four-year study of the active carbonate-water system the Cueva del Agua (Granada, southern Spain that automatically logs the discharge from a stalactite. The results indicate that: (1 the drip water regime is not seasonal, but is linked instead to slow infiltration. Sudden changes in drip water regime occur due to infiltration along preferential flow paths and the draining of water of supersaturated water from reserves in the microfissure and pore system; (2 the drip rate is not linear over time. When dripping is constant, barometric oscillation of the air is the principal factor causing a chaotic a drip flow regime. Over a short period of two to three days, a mean variation in air pressure inside the cave of 10 (±3.7 mbar causes a oscillation the drip rate of 0.5 (±0.2 mm/h. The increase air translates into an the relative thickness of the gaseous phase of the drip water at the cost of the aqueous phase, so leading to a reduction the drip rate from the stalactite.

  17. The East River, Colorado Community Watershed: Hydrogeochemical Studies Spanning Scales and Disciplines

    Science.gov (United States)

    Williams, K. H.

    2016-12-01

    The Lawrence Berkeley National Laboratory and its collaborating institutions are establishing a so-called "Community Watershed" in the headwaters of the East River near Crested Butte, Colorado (USA) designed to quantify processes impacting the ability of mountainous systems to retain and release water, nutrients, carbon, and metals. The East River Community Watershed spans a wide range of scales from hillslope to catena to catchment, with surface water and groundwater linking these geomorphic compartments. Research is highly multi-disciplinary involving a diverse collection of hydrologists, plant ecologists, geochemists, geomorphologists, microbiologists, and climate scientists pursuing both mechanistic and synoptic studies. Studies are focused on assessing the impact of climate perturbations, such as early snowmelt, on coupled ecohydrological and biogeochemical processes as they relate to both water availability and water quality. Data collection activities and monitoring infrastructure are emplaced within the catchment in such a way as to assess the aggregate impact of fine scale processes on catchment scale behavior. Monitoring occurs over diversity of time scales from minutes to months to years, with observational data being used to populate and constrain reactive transport models describing water and nutrient flows across the aforementioned scales of enquiry. Strong infrastructural investments in both data and monitoring networks include dispersed stream gaging, spatially distributed stream water sampling, meteorological station networks, elevation dependent fluxes of carbon and water, and remote sensing datasets, designed to establish baseline data required to assess the impacts of both natural and simulated climate perturbations (e.g. snowmelt manipulation).

  18. Investigating the provenance of thermal groundwater using compositional multivariate statistical analysis: a hydrogeochemical study from Ireland

    Science.gov (United States)

    Blake, Sarah; Henry, Tiernan; Murray, John; Flood, Rory; Muller, Mark R.; Jones, Alan G.; Rath, Volker

    2016-04-01

    The geothermal energy of thermal groundwater is currently being exploited for district-scale heating in many locations world-wide. The chemical compositions of these thermal waters reflect the provenance and hydrothermal circulation patterns of the groundwater, which are controlled by recharge, rock type and geological structure. Exploring the provenance of these waters using multivariate statistical analysis (MSA) techniques increases our understanding of the hydrothermal circulation systems, and provides a reliable tool for assessing these resources. Hydrochemical data from thermal springs situated in the Carboniferous Dublin Basin in east-central Ireland were explored using MSA, including hierarchical cluster analysis (HCA) and principal component analysis (PCA), to investigate the source aquifers of the thermal groundwaters. To take into account the compositional nature of the hydrochemical data, compositional data analysis (CoDa) techniques were used to process the data prior to the MSA. The results of the MSA were examined alongside detailed time-lapse temperature measurements from several of the springs, and indicate the influence of three important hydrogeological processes on the hydrochemistry of the thermal waters: 1) increased salinity due to evaporite dissolution and increased water-rock-interaction; 2) dissolution of carbonates; and 3) dissolution of metal sulfides and oxides associated with mineral deposits. The use of MSA within the CoDa framework identified subtle temporal variations in the hydrochemistry of the thermal springs, which could not be identified with more traditional graphing methods (e.g., Piper diagrams), or with a standard statistical approach. The MSA was successful in distinguishing different geological settings and different annual behaviours within the group of springs. This study demonstrates the usefulness of the application of MSA within the CoDa framework in order to better understand the underlying controlling processes

  19. Hydrogeochemical characterization of groundwater in the Outaouais Region (Québec, Canada) - A regional scale study

    Science.gov (United States)

    Montcoudiol, N.; Molson, J. W.; Lemieux, J.

    2013-12-01

    As part of the Québec regional groundwater characterization program (PACES), a detailed groundwater quality survey was undertaken in the Outaouais Region (Québec, Canada). During the summers of 2011 and 2012, 139 samples were taken from municipal and private wells which were analysed for major ions, nutrients, metals and sulphides. About 70% of the samples were obtained from bedrock wells, mainly in the Canadian Shield and the remainder from wells screened in Quaternary deposit aquifers. Hydrogeochemical facies were determined for 127 samples which had anion-cation charge balance errors within ×10 %. Ca-HCO3 is the dominant water type (65%) which was mainly found in unconfined aquifers, especially Quaternary deposits, and is typical of recently infiltrated rainwater. Other relevant water types are Na-HCO3 and Na-Cl (17 and 6% respectively), characteristic of confined aquifers. This classification by water type is supported by multivariate statistical analysis, namely Principal Component Analysis (PCA) and Hierarchical Clustering Analysis (HCA). PCA allows the identification of three factors controlling groundwater chemistry: salinity, silicate dissolution and F-bearing mineral dissolution. HCA results show that the samples can be grouped into seven clusters. Clusters 1 to 4 are mostly Ca-HCO3 water type and are representative of the enrichment in major ions due to carbonate and silicate dissolution, cluster 1 being closer to rainwater and cluster 4 the most evolved. Cluster 5, made of one sample with a particular chemistry, is not yet fully understood. Samples from cluster 6 present various degrees of Na-Ca exchange, a consequence of remnant Champlain Sea water (some samples from cluster 7 in confined zones) being replaced by infiltrating recharge water. Samples from cluster 7 are evolved waters with high Total Dissolved Solid (TDS) concentrations: they are remnants of the Champlain Sea in confined aquifers (bromide detected) or diluted/mixed by infiltrating

  20. River-spring connectivity and hydrogeochemical interactions in a shallow fractured rock formation. The case study of Fuensanta river valley (Southern Spain)

    Science.gov (United States)

    Barberá, J. A.; Andreo, B.

    2017-04-01

    In upland catchments, the hydrology and hydrochemistry of streams are largely influenced by groundwater inflows, at both regional and local scale. However, reverse conditions (groundwater dynamics conditioned by surface water interferences), although less described, may also occur. In this research, the local river-spring connectivity and induced hydrogeochemical interactions in intensely folded, fractured and layered Cretaceous marls and marly-limestones (Fuensanta river valley, S Spain) are discussed based on field observations, tracer tests and hydrodynamic and hydrochemical data. The differential flow measurements and tracing experiments performed in the Fuensanta river permitted us to quantify the surface water losses and to verify its direct hydraulic connection with the Fuensanta spring. The numerical simulations of tracer breakthrough curves suggest the existence of a groundwater flow system through well-connected master and tributary fractures, with fast and multi-source flow components. Furthermore, the multivariate statistical analysis conducted using chemical data from the sampled waters, the geochemical study of water-rock interactions and the proposed water mixing approach allowed the spatial characterization of the chemistry of the springs and river/stream waters draining low permeable Cretaceous formations. Results corroborated that the mixing of surface waters, as well as calcite dissolution and CO2 dissolution/exsolution, are the main geochemical processes constraining Fuensanta spring hydrochemistry. The estimated contribution of the tributary surface waters to the spring flow during the research period was approximately 26-53% (Fuensanta river) and 47-74% (Convento stream), being predominant the first component during high flow and the second one during the dry season. The identification of secondary geochemical processes (dolomite and gypsum dissolution and dedolomitization) in Fuensanta spring waters evidences the induced hydrogeochemical

  1. Importance of hydrogeochemical processes in the coastal wetlands: A case study from Edremit-Dalyan coastal wetland, Balıkesir-Turkey

    Science.gov (United States)

    Somay, Melis A.

    2016-11-01

    Investigating the hydrogeochemical properties of wetlands allow us to protect them in a sustainable fashion in global scale. Edremit-Dalyan coastal wetland (EDCW) is located in southern part of Biga Peninsula (Mount Ida) which is the most important eco-tourism center in Turkey. Water sampling was done from the hydrologic basin of coastal wetland that consists of a geothermal site, ore deposits area, treatment facility area and olive tree breeding area. EC values of wetland vary between 440 and 2190 μS/cm and water type shows a shift from CaHCO3 to NaClSO4. Al, As, Cd, Cu, Fe, Pb and Zn concentrations exceed the tolerance limits in wetland area probably due to ore deposits around the Edremit Plain. Concentrations of As are high in wetland area exceeding both aquatic life and drinking water As standards of 10 μg/L by as much as 3 times are observed. The dominant As species is As (III). For the living organisms, this situation can be dangerous. Oxygen-18 and deuterium composition of the samples between -7.18 and -6.13‰, and between -42.6 and -34.4‰, respectively in the study area and all the waters are of meteoric origin. Oxygen-18 enrichment can be observed around Derman and coastal zone due to the geothermal activity and evaporation, respectively.

  2. Meteorological, hydrological and hydrogeological monitoring data and near-surface hydrogeological properties data from Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Werner, Kent (EmpTec, Taeby (Sweden)); Oehman, Johan (Golder Associates AB, Stockholm (Sweden)); Holgersson, Bjoern (SWECO VIAK, Stockholm (Sweden)); Roennback, Kristoffer (Aqualog AB, Goeteborg (Sweden)); Marelius, Fredrick (WSP Sverige, Stockholm (Sweden))

    2008-12-15

    This report presents and analyses meteorological, hydrological and hydrogeological time-series data and near-surface hydrogeological properties data from the Laxemar-Simpevarp area, available in SKB's Sicada database at time of the Laxemar 2.3 data freeze (Aug. 31, 2007). The meteorological data set includes data from two local stations, located on the island of Aespoe and at Plittorp, located further inland. In addition, the data evaluation uses a longer-term data set from 7 surrounding stations, operated by SMHI. As part of this study, a time series is constructed of the water content of snow. According to the data evaluation, the site-average annual precipitation and potential evapotranspiration can be estimated to be on the order of 600 and 535 mm, respectively. In particular, precipitation demonstrates a near-coastal gradient, with less precipitation at the coast compared to areas further inland. The surface-water level data set includes data from 4 lake-level gauging stations and 3 sea-level gauging stations. All lakes are located above sea level, including the near-coastal Lake Soeraa. Hence, no intrusion of sea water to lakes takes place. There is a strong co-variation among the monitored lake-water levels, typically with maxima during spring and minima during late summer and early autumn. Concerning the sea as a hydraulic boundary, the maximum and minimum sea levels (daily averages) during the site-investigation period were -0.52 and 0.71 metres above sea level, respectively, whereas the average sea level was 0.03 metres above sea level (RHB 70). The data set on stream discharge, surface-water temperature and electrical conductivity includes data from 9 discharge-gauging stations in 7 streams. Based on the discharge data, the site-average specific discharge for the years 2005-2007 can be estimated to 165 mm/y, which is within the interval of the estimated long-term average. Overall, discharge-data errors are likely to be small. The hydrogeological

  3. Hydrogeochemical processes controlling the high fluoride concentration in groundwater: a case study at the Boden block area, Orissa, India.

    Science.gov (United States)

    Dey, R K; Swain, S K; Mishra, Sulagna; Sharma, Prachi; Patnaik, Tanushree; Singh, V K; Dehury, B N; Jha, Usha; Patel, R K

    2012-05-01

    The present investigation reports the assessment of hydrochemical/geochemical processes controlling the concentration of fluoride in groundwater of a village in India (Boden block, Orissa). Boden block is one of the severely affected fluoride-contaminated areas in the state of Orissa (India). The sampling and subsequent analysis of water samples of the study area was carried out following standard prescribed methods. The results of the analysis indicate that 36.60% groundwater F(-) concentration exceeds the limit prescribed by the World Health Organization for drinking water. The rock interaction with groundwater containing high concentration of HCO(3)(-) and Na(+) at a higher pH value of the medium could be one of the important reasons for the release of F(-) from the aquatic matrix into groundwater. Geochemical classification of groundwater based on Chadha rectangular diagram shows that most of the groundwater samples having fluoride concentration more than 1.5 mg L(-1) belongs to the Na-K-HCO(3) type. The saturation index values evaluated for the groundwater of the study area indicated that it is oversaturated with respect to calcite, whereas the same is undersaturated with respect to fluorite content. The deficiency of calcium ion concentration in the groundwater from calcite precipitation favors fluorite dissolution leading to excess of fluoride concentration. The risk index was calculated as a function of fluoride level in drinking water and morbidity of fluorosis categorizes high risk for villages of Amera and Karlakote panchayat of Boden block.

  4. Hydrogeochemical studies of the Rustler Formation and related rocks in the Waste Isolation Pilot Plant Area, Southeastern New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, M.D.; Lambert, S.J.; Robinson, K.L. (eds.)

    1991-08-01

    Chemical, mineralogical, isotopic, and hydrological studies of the Culebra dolomite member of the Rustler Formation and related rocks are used to delineate hydrochemical facies and form the basis for a conceptual model for post-Pleistocene groundwater flow and chemical evolution. Modern flow within the Culebra in the Waste Isolation Pilot Plant (WIPP) area appears to be largely north-to-south; however, these flow directions under confined conditions are not consistent with the salinity distribution in the region surrounding the WIPP Site. Isotopic, mineralogical, and hydrological data suggest that vertical recharge to the Culebra in the WIPP area and to the immediate east and south has not occurred for several thousand years. Eastward increasing {sup 234}U/{sup 238}U activity ratios suggest recharge from a near-surface Pleistocene infiltration zone flowing from the west-northwest and imply a change in flow direction in the last 30,000 to 12,000 years. 49 refs., 34 figs., 4 tabs.

  5. Hydrogeochemical analysis and quality evaluation of groundwater ...

    African Journals Online (AJOL)

    A total of 20 groundwater samples from boreholes and hand dug wells withinOnicha-Uburu and its environs were assessed to determine their suitability for irrigation purposes. Physical and hydrogeochemical parameters were evaluated, while techniques such as sodium absorption ratio (SAR), sodium percent, residual ...

  6. Modelagua, a new interactive program of inverse mass-balance model for hydrogeochemical studies -- an example of its application in Aguascalientes, Mexico

    Science.gov (United States)

    Gonzalez, P.; Fagundo, J.; Fagundo, R.; Suárez, M.; Melian, C.; Cortes, A.; Ramos, J. A.

    2003-04-01

    The geochemical models consists on the application of physical-chemical principles to the interpretation of hydrogeochemical systems. This methodology has been developed according to two approaches: a) the inverse one, mass-balance, that uses a well-known data of the chemical composition of the water and the rock with the objective of identifying in a quantitative way the geochemical reactions that give origin to this composition, and b) the direct one that in the basis of some well-known initial conditions of the water-rock system, it predicts the characteristics of the resulting solution of the performance of hypothetical chemical reactions. With the reference of interactive programs such as BALANCE and NETPATH, for modelling net geochemical mass-balance reactions between an initial and final water along a hydrologic flow path, which also computes the mixing proportion of two initial waters and net geochemical reactions that can account for the observed composition of a final water, an interactive program of inverse model has been developed (MODELAGUA) that not only allow starting from well-known data of the chemical composition of the water and the rock to identify in a quantitative way the geochemical reactions that give origin to this composition, but allow to do analysis of mixture of waters and net geochemical reactions that can account for the observed composition of a final water, making use of natural tracer whose geochemical behavior allows them to be used as conservative ions. In this work is presented MODELAGUA, as a new interactive program of inverse model mass-balance and an example in Aguascalientes, Mexico of its application.

  7. Hydrogeochemical characteristics of water intakes from groundwater sources in Seversk

    Science.gov (United States)

    Karmalov, A. I.; Dutova, E. M.; Vologdina, I. V.; Pokrovsky, D. S.; Pokrovskiy, V. D.; Kuzevanov, K. K.

    2016-09-01

    The article describes the hydrogeochemical environment behavior analysis of groundwater intake which, in its turn. provides the utility and drinking water supply for Seversk. The reasons for temporary changes of the hydrogeochemical aquifer indicators in the producing areas have been highlighted. The main factor could be upset hydrodynamic conditions during long-term operation. Changed hydrogeochemical indicators have been revealed not only during the technological water treatment process but also during water transportation to consumers. Chemical composition water changes are related to secondary mineral and sludge formation on technological equipment. Precipitation is a polymineral mixture predominantly a ferrous phase. whereas phosphate and carbonate phases are secondary. Clay minerals are also found.

  8. Hydrogeological and hydrogeochemical characterization of a karstic mountain region

    Science.gov (United States)

    Simsek, Celalettin; Elci, Alper; Gunduz, Orhan; Erdogan, Burhan

    2008-03-01

    Karstic limestone formations in the Mediterranean basin are potential water resources that can meet a significant portion of groundwater demand. Therefore, it is necessary to thoroughly study the hydrogeology and hydrogeochemistry of karstic mountain regions. This paper presents a detailed hydrogeological and hydrogeochemical characterization of the Nif Mountain karstic aquifer system in western Turkey, an important recharge source for the densely populated surrounding area. Based on the geological and hydrogeological studies, four major aquifers were identified in the study area including the allochthonous limestone in Bornova flysch, conglomerate-sandstone and clayey-limestone in Neogene series, and the Quaternary alluvium. Physicochemical characteristics of groundwater were measured in situ, and samples were collected at 59 locations comprised of springs and wells. Samples were analyzed for major ions, isotopic composition, arsenic, boron and heavy metals among other trace elements. It was found that the hydrogeological structure is complex with many springs having a wide range of discharge rates. High-discharge springs originate from allochthonous limestone units, whereas low-discharge springs are formed at the contacts with claystone and limestone units. Using stable isotope analysis data, a δ18O-deuterium relationship was obtained that lies between the Mediterranean meteoric and mean global lines. Tritium analyses showed that low-discharge springs originating from contact zones had longer circulation times compared to the high-discharge karstic springs. Furthermore, hydrogeochemical data revealed that groundwater quality significantly deteriorated as water moved from the mountain to the plains. Heavy metal, arsenic and boron concentrations were generally within drinking-water quality standards with a few exceptions occurring in residential and industrial areas located at the foothills of the mountain. Elevated arsenic concentrations were related to local

  9. 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% of some of the delineated sub-catchments. No major water courses flow through the central part of the site investigation area. Many brooks in the area have been deepened for considerable distances for drainage purposes. The horizontal hydraulic conductivity and specific yield of the till, the values of which are based on measurements, are typical or slightly higher than in the surrounding region. Groundwater levels in Quaternary deposits are very shallow, on average less than 0.7 m below ground during 50% of the time. Post-glacial land uplift, in combination with the flat topography, implies fast shoreline displacement. This has resulted in a young terrestrial system that contains a number of newborn lakes and wetlands. The recently isolated and shallow oligotrophic hardwater lakes that are typical for the area are unique in Sweden.The marine ecosystem at Forsmark is situated in a relatively productive coastal area in a region of otherwise fairly low primary production. The seabed is dominated by erosion and transport bottoms with heterogeneous and mobile sediments, consisting mainly of sand and gravel with varying fractions of glacial clay. Based on an overall conceptual model, it was possible to identify pools and fluxes of elements in the landscape that are of potential relevance for a safety assessment. The quantification of these elements, using both field- and model-based estimates, makes it possible to determine the relative importance of the different ecosystems with regard to elemental transport and accumulation. A special emphasis has been put on the description of transport and accumulation of organic matter, since detailed knowledge on the carbon dynamics provides a way of analysing how different ecosystem components are linked to each other through fluxes of energy, i.e. carbon. This provides a baseline for making predictions of dispersal and accumulation of matter, including radionuclides, within and between ecosystems. By this approach, the safety assessment is provided with a tool to predict how and where radionuclides are transported and accumulated in the landscape, making it possible to calculate potential doses to humans and other biota for the specific site. In the terrestrial landscape at Forsmark, many of the vegetation types are sinks for organic matter. The largest sink is the vegetation itself, but also the soil accumulates organic material, although in smaller quantities. The exception is the wetlands that are of significant importance for accumulation of organic matter and other elements, such as phosphorus, in the soil organic pool. In particular, the reed-dominated wetlands surrounding many of the lakes accumulate large amounts of organic matter and associated elements. The most important inflow of elements to lakes is via water from the terrestrial areas.

  10. Hydrogeochemical characteristics of the River Idrijca (Slovenia

    Directory of Open Access Journals (Sweden)

    Tjaša Kanduč

    2008-06-01

    Full Text Available The hydrogeochemical and isotope characteristics of the River Idrijca, Slovenia, where the world’s second largest mercury (Hg mine is located, were investigated. The River Idrijca, a typical steep mountain river has an HCO3- - Ca2+ - Mg2+ chemical composition. Its Ca2+/Mg2+ molar ratio indicates that dolomite weathering prevails in the watershed. The River Idrijca and its tributaries are over saturated with respect to calcite and dolomite. The pCO2 pressure is up to 13 times over atmospheric pressure and represents a source of CO2 to the atmosphere. δ18O values in river water indicate primary control from precipitation and enrichment of the heavy oxygen isotope of infiltrating water recharging the River Idrijca from its slopes.The δ13 CDIC values range from −10.8 to −6.6 ‰ and are controlled by biogeochemical processes in terrestrial environments and in the stream: 1 exchange with atmospheric CO2, 2 degradation of organic matter, 3 dissolution of carbonates, and 4 tributaries. The contributions of these inputs were calculated according to steady state equations and are estimated to be -11 %: 19 %: 31 %: 61 % in the autumn and 0 %: 6 %: 9 %: 35 % in the spring sampling seasons.

  11. Hydrogeochemical precursors of strong earthquakes in Kamchatka: further analysis

    Directory of Open Access Journals (Sweden)

    P. F. Biagi

    2001-01-01

    Full Text Available For many years, ion and gas content data have been collected from the groundwater of three deep wells in the southern area of the Kamchatka peninsula, Russia. In the last ten years, five earthquakes with M > 6.5 have occurred within 250 km of the wells. In a previous study, we investigated the possibility that the hydrogeochemical time series contained precursors. The technique used was to assume that each signal with an amplitude of three times the standard deviation is an irregularity and we then defined anomalies as irregularities occurring simultaneously in the data for more than one parameter at each well. Using this method, we identified 11 anomalies with 8 of them being possible successes and 3 being failures as earthquake precursors. Precursors were obtained for all five earthquakes that we considered. In this paper, we allow for the cross-correlation found between the gas data sets and in some cases, between the ion data sets. No cross-correlation has been found between gas and ion content data. Any correlation undermines the idea that an anomaly might be identified from irregularities appearing simultaneously on different parameters at each site. To refine the technique, we re-examine the hydrogeochemical data and define as anomalies those irregularities occurring simultaneously only in the data of two or more uncorrelated parameters. We then restricted the analysis to the cases of just the gas content data and the ion content data. In the first case, we found 6 successes and 2 failures, and in the second case, we found only 3 successes. In the first case, the precursors appear only for three of the five earthquakes we considered, and in the second case, only for two, but these are the earthquakes nearest to the wells. Interestingly, it shows that when a strict set of rules for defining an anomaly is used, the method produces only successes and when less restrictive rules are used, earthquakes further from the well are implicated, but

  12. Hydrogeochemical study of water in some aquifers of the Estado de Mexico; Estudio hidrogeoquimico de agua de algunos manantiales del Estado de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Lopez, A.; Balcazar, M.; Flores, J.H.; Cardenas, S. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Schubert, M. [UFZ Centre for Environmental Research Leipzig-Halle GMBH, Permoser Str. 15, 04318 Leipzig (Germany)

    2005-07-01

    The National Institute of Nuclear Research of Mexico (ININ), has developed a technique that allows to study the association of recharge mechanisms, residence times of the water in the aquifers, as well as the local lithology and the geochemical parameters. The viability of this technique was proven on November 2004 in the aquifers (La Perita, El Tunel y El Pedregal) located in the Asuncion Tepexoyuca, Estado de Mexico. It was observed that so much the aquifer El Tunel like La Perita are used for the human consumption, the aquifer of El Pedregal is used for the fish cultivation. The studies were carried out during March 2003 to November 2004. In the aquifer La Perita the maximum values of the radon concentration (0.76 Bq L{sup -1}) they were observed in the summertime time (December). In the spring El Tunel the maximum values of the radon concentration (4.08 Bq L{sup -1}) they were observed in the rainy season (September) this increment can be due to the contributions of the recharge of aquifers that it allows the haulage of the radon of other alternating roads of infiltration of the rain water. Of the physicochemical and radiochemical analyses carried out in the water samples of the studied aquifers, it is deduced that they are waters of good quality since for the human consumption since that they are inside on the maximum permissible limits as for their potability according to national and international standards. Likewise it was observed that the water of the aquifers is a single aquifer, since that its differences they due to the time of permanency of the water inside the aquifer. The classification of the underground water deduced that it is calcic and/or magnesic bi carbonated water belonging to the type of meteoric waters of recent infiltration. (Author)

  13. Isotopic and hydrogeochemical characterization of high-altitude karst aquifers in complex geological settings. The Ordesa and Monte Perdido National Park (Northern Spain) case study

    Energy Technology Data Exchange (ETDEWEB)

    Lambán, L.J., E-mail: javier.lamban@igme.es [Geological Survey of Spain (IGME) (Spain); Jódar, J., E-mail: jorge.jodar@upc.edu [Department of Geotechnical Engineering and Geosciences, Technical University of Catalonia (UPC), Barcelona (Spain); Custodio, E., E-mail: emilio.custodio@upc.edu [Department of Geotechnical Engineering and Geosciences, Technical University of Catalonia (UPC), Barcelona (Spain); Soler, A., E-mail: albertsoler@ub.edu [Grup de Mineralogia Aplicada i Medi Ambient, Departament Cristal lografia Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona (UB) (Spain); Sapriza, G., E-mail: g.sapriza@usask.ca [Global Institute for Water Security, National Hydrology Research Centre (Canada); Soto, R., E-mail: r.soto@igme.es [Geological Survey of Spain (IGME) (Spain)

    2015-02-15

    The Ordesa and Monte Perdido National Park, located in the Southern Pyrenees, constitutes the highest karst system in Western Europe. No previous studies regarding its geochemical and isotopic groundwater characterization are available in this area. This work presents the results of field and sampling campaigns carried out between July 2007 and September 2013. The groundwater presents high calcium bicarbonate contents due to the occurrence of upper Cretaceous and lower Paleocene–Eocene carbonate materials in the studied area. Other relevant processes include dissolution of anhydrite and/or gypsum and incongruent dissolution of Mg-limestone and dolomite. The water stable isotopes (δ{sup 18}O, δ{sup 2}H) show that the oceanic fronts from the Atlantic Ocean are responsible for the high levels of precipitation. In autumn, winter, and spring, a deuterium excess is found in the recharge water, which could be related to local atmospheric transport of low-altitude snow sublimation vapour and its later condensation on the snow surface at higher altitude, where recharge is mostly produced. The recharge zones are mainly between 2500 m and 3200 m a.s.l. The tritium content of the water suggests short groundwater transit times. The isotopic composition of dissolved sulphate points to the existence of regional fluxes mixed with local discharge in some of the springs. This work highlights the major role played by the altitude difference between the recharge and discharge zones in controlling the chemistry and the vertical variability of the isotopic composition in high-altitude karst aquifers. - Highlights: • Environmental tracers are essential to study complex alpine karst aquifers. • The long presence of snow controls the deuterium excess in groundwater. • Seasonal δD content in springs depends on gap between recharge and discharge points. • The first hydrogeological characterization of the Ordesa National Park is presented. • Sulphate content in springs comes

  14. Results of a hydrogeological and hydrogeochemical study of a semi-arid karst aquifer in Tezbent plateau, Tebessa region, northeast of Algeria

    Science.gov (United States)

    Belfar, Dalila; Fehdi, Chemseddine; Baali, Fethi; Salameh, Elias

    2017-06-01

    The Hammamet Plain, situated in the northwest of the Tezbent mountain range, northeast of Algeria, drains carbonate aquifers through some important karst springs. The physical and chemical characteristics of spring and well water samples were studied for 2 years to assess the origin of groundwater and determine the factors driving the geochemical composition. The ionic speciation and mineral dissolution/precipitation was calculated. Water wells, characterizing groundwater circulation at shallow depths, are moderate to high mineralized waters of Na-HCO3 type. In contrast to the shallow environment, the CO2-rich, deeper waters are of the Ca-HCO3-SO4 type and undergo significant changes in the baseline chemistry along flow lines with increasing residence time. The main factors controlling the groundwater composition and its seasonal variations are the geology, because of the presence of carbonate formations, the elevation and the rate of karst development. In both groups, the carbonate chemistry is diagnostic of the effect of karst development. The supersaturation with respect to calcite indicates CO2 degassing, occurring either inside the aquifer in open conduits, or at the outlet in reservoirs. The undersaturation with respect to calcite shows the existence of fast flow and short residence time conditions inside the aquifer. Interaction between groundwater and surrounding host rocks is believed to be the main process responsible for the observed chemical characteristics of groundwater in the study area.

  15. Geological and hydrogeochemical research, tools for karst management in the north of the Caraş Gorges (Banat Mountains, Romania)

    OpenAIRE

    Marius Vlaicu; Cristian Mihai Munteanu; Constantin Marin; Alin Tudorache

    2010-01-01

    The karst geosystems functioning frequently implies very quick mass and energy transfers, which make them highly sensitive to any natural or anthropogenic disturbance. Therefore, the groundwater resources, threatened by agricultural and industrial pollution, should be carefully exploited, taking into account the intrinsic vulnerability of the region. This paper aims to present the results of the geological, geomorphological and hydrogeochemical studies carried out in the Banat Mountains (Roma...

  16. Hydrogeochemical and isotopic characterization of Pesnica River, Slovenia

    Directory of Open Access Journals (Sweden)

    Tjaša Kanduč

    2016-12-01

    Full Text Available The surface water geochemistry and carbon cycling studied here depend mainly on geological composition of the river catchment. The investigated surface waters in the river Pesnica catchment that are heavily hydromorphologicaly altered (reservoirs, channelization, land melioration systems represent waters inflenced by chemical weathering of carbonates and of mostly clastic rocks (claystone, sandstones, marlstones and siltstones. The objectives of our study were to analyze hydrogeochemical and isotopic composition of dissolved (δ13CDIC and particulate carbon (δ13CPOC with characterization of suspended matter and evaluate biogeochemical processes in Pesnica River in Slovenia before and after the retention. Surface waters are generally close to saturation regarding calcite and dolomite, dissolved CO2 is 49 to 1000 times oversaturated relative to atmosphere. δ13C DIC was in the range from -14.8 to -4.2 ‰ and shows following biogeochemical processes in river system: degradation of organic matter, dissolution of carbonates and biological activity, which was confimed with SEM microscopy and EDXS microanalysis. Results of SEM/EDXS showed that suspended matter is composed of K, Mg and Ca from locations Pesnica 1 and Pesnica 2 (above retention Perniško lake. Sample from Pesnica 3 (below retention shows higher biological activity, while sample from Pesnica 4 (tributary of Pesnica, drainage channel Biš contains a lot of particles of microporous structure and fier structure, which are probably of anthropogenic origin. δ13CPOC is changing from -29.5 to-27.6‰ and showed different stages of degraded terrestrial material. More negative δ13CPOC are shown at location at drainage channel Biš and show higher terrestrial input in river system as locations 1, 2 and 3 Pesnica, which have higher δ13CPOC values. This fist results about suspended matter in Pesnica watershed serve for evaluation of anthropogenic inflences specially in relation with further

  17. Uranium Hydrogeochemical and Stream Sediment Reconnaissance in southwestern Montana

    Energy Technology Data Exchange (ETDEWEB)

    Broxton, D.E.

    1978-02-01

    The Los Alamos Scientific Laboratory conducted a Hydrogeochemical and Stream Sediment Reconnaissance in southwestern Montana from early August to mid-October of 1976. A total of 1240 water and 1933 sediment samples were collected from 1994 locations at a nominal density of one location per 10 km/sup 2/. The water samples were collected from streams, wells, and springs; sediment samples were taken at streams and springs. All samples were analyzed at Los Alamos for total uranium by fluorometry or delayed-neutron counting. The uranium content of water samples ranges from below the detection limit (less than 0.3 ppB) to 45.30 ppB and has a mean value of 1.40 ppB. The uranium content of the sediment samples ranges between 0.20 and 206.80 ppM and averages 6.12 ppM. The chosen uranium anomaly threshold value was 7 ppB for surface waters (streams), 9 ppB for groundwaters (wells and springs), and 25 ppM for all sediment samples. The study area consists of the following lithologic groups: Precambrian basement complex, Precambrian Belt metasediments, Paleozoic and Mesozoic shelf sediments, Cretaceous and early Tertiary volcanic and plutonic rocks, Laramide orogenic clastic sediments, and middle to late Tertiary volcanic rocks and intermontane basin sediments. Most of the anomalous water and sediment samples with well-developed dispersion trains occur in areas underlain by or adjacent to silicic plutonic rocks of the Idaho and Boulder batholiths. These anomalies may indicate the presence of uraniferous veins and pegmatites similar to those already known to exist in the area. Fewer anomalous water samples occur in areas underlain by Precambrian basement complex and Tertiary basin fill.

  18. Water Quality and Hydrogeochemical Characteristics of Surface Water and Groundwaters in Aksu (Isparta Plain

    Directory of Open Access Journals (Sweden)

    Şehnaz Şener

    2015-12-01

    Full Text Available In this study, geological, hydrological, hydrogeological, hydrogeochemical characteristics of the Aksu (Isparta plain were investigated. In addition, determination of the water quality and availability in current status besides groundwater dynamics were aimed in the scope of work. The study area is located in the southwest Turkey, and lithological units belonging to Beydaglari autochthonous and Antalya nappes are observed. The most important surface water and groundwater reservoirs are Aksu river and alluvial-karst aquifers, respectively. Hydrogeochemical characteristics and quality of the water are important because water is used as drinking water and irrigation water in the plain. For this purpose, in situ measurements and chemical analyzes were carried out in the period of May-2013 on water resources. According to the obtained results, water resources is Mg-HCO3, Ca-HCO3, and Mg-Ca-HCO3 facies. According to the Water Pollution Control Regulation, all surface and groundwaters are determined in 4th water quality class in terms of sulfur owing to water-rock interaction. The assessment of the usage properties of the waters indicate that water sources is suitable for drinking and irrigation water usage in generally.

  19. Hydrogeochemical Evolution of the Laxemar Site

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B. (Univ. of Zaragoza (Spain)); Salas, Joaquin; Molinero, Jorge (Amphos 21, Barcelona (Spain))

    2010-11-15

    induce changes in the geochemical composition of groundwater around the repository. In this way, the present report summarizes the results obtained by the geochemical simulations performed to simulate the hydrogeochemical evolution of groundwaters in the Laxemar area. In the safety assessment of the candidate repository site, a series of functions and parameters must be evaluated. From a geochemical point of view, the most important are redox properties, pH and concentration of solutes. Other factors to be considered are the groundwater content of potassium, sulphide and iron, as they might affect the chemical stability of the buffer and the canister. Additionally, the effects of grouting in the geosphere and cement materials in the engineered barriers could affect groundwater's pH. Discussions of the results will be focused on these aspects. The starting point of the geochemical calculations is a series of hydrological models (using ConnectFlow and DarcyTools), which, based on the understanding of the palaeohydrogeological history of the sites (which assumes the presence of different water mixing events due to the input of different reference waters over the time), have provided information on (1) the transport of fractions of selected reference waters (deep saline, old meteoric, glacial, marine and present meteoric waters), in the case of the temperate period, or (2) the transport of salts, in the case of the glacial cycle. In the latter case, the rock volume initially contains a mixture of two reference waters: a deep saline groundwater and a dilute water from meteoric origin. The proportion of these two waters can be obtained from the salinity at any point in the rock volume. With the advancement and retreat of the glacier, the proportion of a third mixing end-member is calculated from the decrease of salinity at any point in the rock volume (a newly incoming glacial melt-water), changing the proportions of the other two reference waters correspondingly. Finally

  20. Hydrogeochemical Analysis of an Overexploited Aquifer In Bangladesh Toward Managed Aquifer Recharge Project Implementation

    Science.gov (United States)

    Rahman, M. A.; Wiegand, B. A.; Pervin, M.; Sauter, M.

    2012-12-01

    In most parts of the upper Dupitila aquifer (Dhaka City, Bangladesh) the average groundwater depletion reaches 2-3 m/year due to increasing water demands of the growing population. To counteract overexploitation of the aquifer, a more sustainable water management is required. The analysis of the local water resources system suggests that Managed Aquifer Recharge (MAR) would help to restore groundwater resources to strengthen water supply of Dhaka City, e.g., by using collected urban monsoon runoff and excess surface water from rivers. To assess possible effects of surface water or rainwater injection on groundwater quality, a comprehensive hydrogeochemical survey of the Dupitila aquifer is required. This paper presents hydrogeochemical data to document the current status of groundwater quality and to evaluate potential groundwater pollution by mobilization of hazardous chemicals as a result of changes in the hydrochemical equilibria. We performed a comprehensive review of available secondary data sources and will present new results from hydrochemical and Sr isotope investigations of water samples that were conducted within this study. Currently, groundwater quality in the upper Dupitila aquifer is characterized by variations in the electrical conductivity in the range of 200 to 1100 μS/cm, which may indicate some anthropogenic contamination by leakage from waste disposal including the sewage network and from surface water infiltration into the groundwater aquifer. Dissolved oxygen concentrations range from 1.0 to 4.9 mg/L (average 2.5 mg/L) in the upper Dupitila aquifer, while the lower Dupilita aquifer shows dissolved oxygen concentrations in the range 0 to 0.7 mg/L. Concentrations of major ions show some variation primarily due to a sedimentologically/mineralogically heterogeneous aquifer composition (sand, gravel, clay horizons), but may also be affected by anthropogenic processes. The groundwater composition is predominated by Ca-Mg-HCO3 and saturation values

  1. HYDROGEOCHEMICAL CHARACTERISTICS OF THE ST. IVAN SPRING IN ISTRIA, CROATIA

    Directory of Open Access Journals (Sweden)

    Tatjana Vlahović

    2000-12-01

    Full Text Available In addition to geological, hydrogeological investigations and groundwater tracing, detailed surveying of the groundwater quality is becoming particularly important for environmental impact monitoring on karst aquifers. Groundwater quality data contain two types of information i.e. the natural chemistry of water and its modifications caused by antropogenic impacts. The method of results presentation as well as the importance of water quality surveying particularly with respect to the indicators showing its natural chemistry, are shown here exemplified by the St. Ivan spring in Istria, Croatia. Natural chemistry of the groundwater is a consequence of hydrogeochemical facies, and it is used here for interpretation of spring generating conditions and the origin of groundwater. Results obtained so far confirm that the extent of recharge area of the spring change in dependence of the hydrological conditions. Hydrogeochemical characteristics of the spring are presented graphically in the form of correlation diagrams showing major groundwater parameters, saturation conditions and trends of particular parameters as a function of time.

  2. Hydrogeochemical attributes and ground water quality of Ngbo Community in Ohaukwu Area Council, Ebonyi State, Nigeria

    Directory of Open Access Journals (Sweden)

    Omaka Ndukaku Omaka

    2015-01-01

    Full Text Available This study evaluated the hydrogeochemical attributes and quality of groundwater resources in Ngbo, Ohaukwu Area Council of Ebonyi State, Nigeria in order to determine whether boreholes in the area were suitable for potable uses. Eleven groundwater samples were collected from hand-dug boreholes between February and March, 2013. The physiochemical parameters of the samples were then analyzed to determine electrical conductivity, total dissolved solids, total alkalinity, major cations and anions, and trace metals. The quality of these characteristics was evaluated by comparing them to the Nigerian Institute of Standards, the Bureau of Indian Standards and the World Health Organization standards for drinking water quality. Mass abundance of the major ions was in the order of Mg2+ > Ca2+ for cations, Cl- > SO4 2 - > NO3 - > PO4 3 - for anions and Fe > As > Mn > Cu > Zn > Cr > Ni > Pb > Cd for trace metals. Correlation analysis revealed both positive and negative correlations among the parameters. Also, one-way ANOVA tests revealed that no significant differences existed between physiochemical parameters (F = 1.004 < Fcrit =1.977, major cations and anions (F =0.547 < Fcrit =2.008 and trace metals (F = 0.772 < Fcrit = 1.940 regardless of the sampling location. Groundwater in the area was generally hard, alkaline and highly mineralized, making it unsuitable for drinking in some places due to high total hardness and TDS; but it was generally suitable for irrigation purposes. It is recommended that boreholes be flushed regularly to aid in the removal of mineralized deposits, and that regular hydrogeochemical studies be conducted in order to detect future deterioration of water quality

  3. Hydrogeochemical analysis and evaluation of surface water quality of Pratapgarh district, Uttar Pradesh, India

    Science.gov (United States)

    Tiwari, Ashwani Kumar; Singh, Abhay Kumar; Singh, Amit Kumar; Singh, M. P.

    2017-07-01

    The hydrogeochemical study of surface water in Pratapgarh district has been carried out to assess the major ion chemistry and water quality for drinking and domestic purposes. For this purpose, twenty-five surface water samples were collected from river, ponds and canals and analysed for pH, electrical conductivity, total dissolved solids (TDS), turbidity, hardness, major cations (Ca2+, Mg2+, Na+ and K+), major anions (HCO3 -, F-, Cl-, NO3 -, SO4 2-) and dissolved silica concentration. The analytical results show mildly acidic to alkaline nature of surface water resources of Pratapgarh district. HCO3 - and Cl- are the dominant anions, while cation chemistry is dominated by Na+ and Ca2+. The statistical analysis and data plotted on the Piper diagram reveals that the surface water chemistry is mainly controlled by rock weathering with secondary contributions from agriculture and anthropogenic sources. Ca2+-Mg2+-HCO3 -, Ca2+-Mg2+-Cl- and Na+-HCO3 --Cl- are the dominant hydrogeochemical facies in the surface water of the area. For quality assessment, values of analysed parameters were compared with Indian and WHO water quality standards, which shows that the concentrations of TDS, F-, NO3 -, Na+, Mg2+ and total hardness are exceeding the desirable limits in some water samples. Water Quality Index (WQI) is one of the most effective tools to communicate information on the quality of any water body. The computed WQI values of Pratapgarh district surface water range from 28 to 198 with an average value of 82, and more than half of the study area is under excellent to good category.

  4. Hydrogeochemical signatures of thermal springs compared to deep formation water of North Germany

    Science.gov (United States)

    Bozau, Elke; van Berk, Wolfgang

    2014-05-01

    Thermal springs and hot deep formation waters can be used for geothermal energy production. Depending on the chemical composition of the used waters, geothermal power plants have to deal with scaling and corrosion effects. Therefore, the understanding of the hydrogeochemical behaviour of such waters can be helpful to enhance the efficiency of the energy production. This study is comparing hydrogeochemical characteristics of thermal springs in the Harz Mountains (North Germany) and deep formation water of the North German Basin. The Harz Mountains consist of uplifted Palaeozoic rocks, whereas the North German Basin consists of sedimentary layers of Permian, Mesozoic and Cenozoic age. Volcanic rocks are included in the Permian layers. The thickness of the sedimentary basin varies between 2 km and more than 8 km. The deep aquifers of the North German Basin are mostly not involved in the recent meteoric water cycle. Their waters have contents of Total Dissolved Solids (TDS) up to about 400 g/L. Thermal springs of the Harz Mountains are situated close to the main fracture system of the region. These springs are connected to the meteoric water cycle and display lower contents of TDS (Harz Mountains and the North German Basin. The concentrations of calcium, sodium, and chloride differ due to salt dissolution and feldspar transformation (albitisation) in the thermal springs as well as in the deep formation waters. Based on today's knowledge hydrochemical and stratigraphical data from the North German Basin can be used to elucidate the geological origin of the thermal springs in the Harz Mountains. Acknowledgements. The presented data are results of the collaborative research program "gebo" (Geothermal energy and high performance drilling), financed by the Ministry of Science and Culture of the State of Lower Saxony and the company Baker Hughes.

  5. Hydrogeochemical contrast between brown and grey sand aquifers in shallow depth of Bengal Basin: consequences for sustainable drinking water supply.

    Science.gov (United States)

    Biswas, Ashis; Nath, Bibhash; Bhattacharya, Prosun; Halder, Dipti; Kundu, Amit K; Mandal, Ujjal; Mukherjee, Abhijit; Chatterjee, Debashis; Mörth, Carl-Magnus; Jacks, Gunnar

    2012-08-01

    Delineation of safe aquifer(s) that can be targeted by cheap drilling technology for tubewell (TW) installation becomes highly imperative to ensure access to safe and sustainable drinking water sources for the arsenic (As) affected population in Bengal Basin. This study investigates the potentiality of brown sand aquifers (BSA) as a safe drinking water source by characterizing its hydrogeochemical contrast to grey sand aquifers (GSA) within shallow depth (water guidelines, which warrants rigorous assessment of attendant health risk for Mn prior to considering mass scale exploitation of the BSA for possible sustainable drinking water supply. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Hydrogeochemical and isotopic characterization of the groundwater ...

    African Journals Online (AJOL)

    Additionally, to these findings, this article discussed the anthropogenic processes involved, whose effects are evident in many samples with nitrate concentrations above the WHO standards. Generally, the groundwater in the study area show signs of human contamination. Recent studies also indicate the development of ...

  7. New insight into unstable hillslopes hydrology from hydrogeochemical modelling.

    Science.gov (United States)

    Bertrand, C.; Marc, V.; Malet, J.-P.

    2010-05-01

    In the black marl outcrops of the French South Alps, sub surface flow conditions are considered as the main triggering factor for initiation and reactivation of landslides. The problem is traditionally addressed in term of hydrological processes (how does percolation to the water table occur?) but in some cases the origin of water is also in question. Direct rainfall is generally assumed as the only water source for groundwater recharge in shallow hillslope aquifers. The bedrock is also supposed impervious and continuous. Yet the geological environment of the study area is very complex owing to the geological history of this alpine sector. The autochthonous callovo-oxfordian black marl bedrock is highly tectonized (Maquaire et al., 2003) and may be affected by large, possibly draining discontinuities. A deep water inflow at the slip surface may at least locally result in increase the pore pressure and decrease the effective shearing resistance of the landslide material. In the active slow-moving landslide of Super-Sauze (Malet and Maquaire, 2003), this question has been addressed using hydrochemical investigations. The groundwater was sampled during five field campaigns uniformly spread out over the year from a network of boreholes. Water chemistry data were completed by geochemical and mineralogical analyses of the marl material. The major hydro-geochemical processes over area proved (1) mixing processes, (2) pyrite alteration, (3) dissolution/precipitation of carbonates and (4) cations exchange (de Montety et al., 2007). A geochemical modelling was carried out using the model Phreeqc (Parkhurst and Appelo, version 2.15, 2008) to check how suitable was observed water chemistry with the reservoir characteristics. The modelling exercise was based on a kinetics approach of soil-water interactions. The model simulates the rock alteration by the dissolution of the primary minerals and the precipitation of new phases. Initial parameters were obtained from geochemical

  8. Identification of hydrogeochemical processes in groundwater using ...

    African Journals Online (AJOL)

    The study approach includes detailed geochemical analysis of groundwater samples collected from domestic boreholes for major constituents such as Ca2+, Mg2+, Na+, K+, HCO3, Cl-, SO4 2-, and NO3- and the hydrochemical data was subjected to multivariate statistical analysis and conventional graphical plots.

  9. Hydrogeochemical evolution and potability evaluation of saline ...

    Indian Academy of Sciences (India)

    However, the aquifer system displays an even distribution of strong and weak acids for both the monsoonal regimes. Thehydrogeochemistry is controlled by aquifer lithology with a general occurrence of ion exchange and acid–base reaction processes across the study area. Spatial disposition of major cations indicates ...

  10. Hydrogeochemical analysis for Tasuj plain aquifer, Iran

    Indian Academy of Sciences (India)

    Dendrograms from 2000 to 2009 were studied to understand the temporal variation of groundwater quality. Comparing the distributions of groundwater types in 2000 and 2009, we found that the mixing zone was expanded. This may be due to artificial groundwater recharge in the recharge area and the effect of inverse ion ...

  11. Hydrogeochemical analysis for Tasuj plain aquifer, Iran

    Indian Academy of Sciences (India)

    However, hierarchical cluster analysis (HCA) identified five water types in the groundwater samples because HCA was able to analyze ... ture, industry and public uses. This study focuses on the Tasuj plain aquifer, one of the ... rectly by cluster analysis (Lambrakis et al. 2004;. Singh et al. 2004). In summary, multivariate sta-.

  12. Hydrogeochemical and isotopic characterization of the groundwater ...

    African Journals Online (AJOL)

    POSTE7

    hardness (Durfor and Becker, 1964). About 40% of the sampled groundwater is considered hard compared to the WHO standard; while 60.87% of the groundwater in the study area can be considered soft, 17.39% moderately hard, 13.04% hard and 8.7% very hard. The problem of hard water is primarily because it does not.

  13. Groundwater circulation and hydrogeochemical evolution in ...

    Indian Academy of Sciences (India)

    In this study, analysis of hydrogeological conditions, as well as hydrochemistry and isotopic tools were used to get an insight into the processes controlling mineralization, recharge conditions, and flow pattern of groundwater in a typical arid alluvial-lacustrine plain in Qaidam Basin, northwest China. Analysis of the dissolved ...

  14. Preliminary Hydrogeochemical Site Description SFR (version 0.2)

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin (Geosigma AB, Uppaala (Sweden)); Tullborg, Eva-Lena (Terralogica AB, Graabo (Sweden)); Smellie, John (Conterra AB, Partille (Sweden))

    2010-05-15

    The final repository for low and intermediate level radioactive operational waste, SFR, located about 150 km north of Stockholm, is to undergo a future extension. The present on-going project, scheduled from 2007 to 2011, is to define and characterise a suitable bedrock volume for the extended repository. This will include the drilling and geoscientific evaluation of seven core-drilled and four percussion boreholes as well as subsequent interpretation and modelling based on the obtained results in order to provide the necessary information for safety assessment and repository design. This report presents a preliminary hydrogeochemical site description for the SFR site and should be considered as an early progress report rather than a complete hydrochemical site descriptive model. The completed hydrogeochemical field investigations have yielded chemical data from a total of 12 borehole sections in five boreholes and additional data from the entire length of two open boreholes in connection with hydraulic tests. These data, together with data from a total of 18 early boreholes in the present SFR tunnel system, were used in the interpretation work. The main part of the data consisted of basic groundwater analyses including major ions and isotopes. Some sporadic gas, microbe and measured redox data are available, but these are either not treated in this report, or are only briefly discussed. This was due to time constraints since special care is needed when interpreting few data of varying quality. The groundwaters in the SFR dataset cover a maximum depth down to about .400 masl and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the delta18O values show a wide variation (-1.55 to -0.75% V-SMOW) similar to that reported from the Forsmark site investigations. At the SFR, marine indicators such as Mg/Cl, K/Cl and Br/Cl also show relatively large variations considering the limited salinity range. From very few measured Eh values, and

  15. Hydrogeochemical conditions at the Haestholmen site

    Energy Technology Data Exchange (ETDEWEB)

    Luukkonen, A.; Pitkaenen, P. [VTT Communities and Infrastructure, Espoo (Finland); Ruotsalainen, P. [Fintact Oy (Finland); Leino-Forsman, H. [VTT Chemical Technology, Espoo (Finland); Snellman, M. [Posiva Oy, Helsinki (Finland)

    1999-06-01

    The characterisation and interpretation of groundwater geochemistry has been ongoing at several study sites for spent fuel disposal in Finland since the late 1980s. The former evaluation of the Haestholmen groundwater from depths to 240 m was performed between 1980 and 1992 during the investigations for the construction of the reactor waste repository. Haestholmen was included in the site characterisation programme for spent fuel disposal in 1997. The sampling of groundwater down to 1000 m was started in 1997 from deep boreholes and this study presents the evaluation of the hydro-geochemistry at Haestholmen extending below 200m. The dilute HCO{sub 3}-rich groundwater seems to be limited to the upper 60 m and it is probably controlled by subhorizontal zone R1. According to the tritium data, the dilute groundwater is recently infiltrated, less than 45 years ago. Brackish SO{sub 4}-rich groundwater has been obtained from a depth of about 60 m to a depth of about 600 m. The data show a strong input of the Litorina sea water mixed in the groundwater system as well as input of glacial melt water in the brackish ground-water layer. The infiltration of Litorina sea water is based on marine Br/Cl ratios, {delta}O-18/{delta}H-2, and {delta}S-34 data. The C-14 datings, together with a higher salinity than the present Baltic indicate a Litorina Sea water origin. Melt water is interpreted according to decreasing {delta}H-2 and {delta}O-18 with salinity and depth in the brackish water layer. The saline groundwater is obtained from below 600 m. Stable isotope ({delta}O-18 and {delta}H-2) results, high Ca/Cl, Ca/Mg and Br/Cl ratios suggest a hydrothermal saline end-member. However, the marine signature is also observable in saline water, which is interpreted to originate from the Pre-Weichselian Sea, possibly from the Eem Sea. In accordance with another study site, Olkiluoto, the hydrochemistry of Haestholmen seems to contain a layered sequence of climatic and shoreline changes

  16. Hydrogeochemical modelling of geothermal systems in the Malm Aquifer

    Science.gov (United States)

    Baumann, Thomas; Ueckert, Martina

    2017-04-01

    The Malm sediments in the Bavarian Molasse Basin are very suitable for hydrogeothermal heat and energy production and for energy storage. With the conversion of the Pullach injection well to a production well it was possible to quantify the reactions in the reservoir and to validate the hydrogeochemical models. This data set was complemented by the results from a heat storage test. The calibrated hydrogeochemical model was used to predict and optimize the long term behaviour of geothermal doublets. In facilities using more than two wells, mixing ratios for the production wells were assessed and optimized. Most of the simulations showed a benign long-term behaviour, even in more complex systems. Dissolution of carbonates at the injection wells propagates into the reservoir and contributes to an increase of the injectivity. It also seems to be possible to make use of the gas load which is otherwise crucial to maintain to prevent the formation of scalings. The situation changes for geothermal heat storage systems, eg. a geothermal doublet in combination with a combined heat and power plant. The cyclic operation causes a significant increase of the carbonate concentrations. Consequently, the amount of eg. CO2 that has to be added to the water to prevent precipitation of carbonates during the heating cycle, has to increase as well. The simulation results show that a doublet system for heat storage reaches an unstable situation after a few cycles. These results are supported by the data form a heat storage test and by the data from the conversion of the Pullach well. The model also shows that long-term operation is possible in a triplet setup.

  17. 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

  18. Comprehensive studies of hydrogeochemical processes and quality status of groundwater with tools of cluster, grouping analysis, and fuzzy set method using GIS platform: a case study of Dalcheon in Ulsan City, Korea.

    Science.gov (United States)

    Venkatramanan, S; Chung, S Y; Rajesh, R; Lee, S Y; Ramkumar, T; Prasanna, M V

    2015-08-01

    This research aimed at developing comprehensive assessments of physicochemical quality of groundwater for drinking and irrigation purposes at Dalcheon in Ulsan City, Korea. The mean concentration of major ions represented as follows: Ca (94.3 mg/L) > Mg (41.7 mg/L) > Na (19.2 mg/L) > K (3.2 mg/L) for cations and SO4 (351 mg/L) > HCO3 (169 mg/L) > Cl (19 mg/L) for anions. Thematic maps for physicochemical parameters of groundwater were prepared, classified, weighted, and integrated in GIS method with fuzzy logic. The maps exhibited that suitable zone of drinking and irrigation purpose occupied in SE, NE, and NW sectors. The undesirable zone of drinking purpose was observed in SW and central parts and that of irrigation was in the western part of the study area. This was influenced by improperly treated effluents from an abandoned iron ore mine, irrigation, and domestic fields. By grouping analysis, groundwater types were classified into Ca(HCO3)2, (Ca,Mg)Cl2, and CaCl2, and CaHCO3 was the most predominant type. Grouping analysis also showed three types of irrigation water such as C1S1, C1S2, and C1S3. C1S3 type of high salinity to low sodium hazard was the most dominant in the study area. Equilibrium processes elucidated the groundwater samples were in the saturated to undersaturated condition with respect to aragonite, calcite, dolomite, and gypsum due to precipitation and deposition processes. Cluster analysis suggested that high contents of SO4 and HCO3 with low Cl was related with water-rock interactions and along with mining impact. This study showed that the effluents discharged from mining waste was the main sources of groundwater quality deterioration.

  19. Hydrogeochemical investigation of groundwater in shallow coastal aquifer of Khulna District, Bangladesh

    Science.gov (United States)

    Islam, S. M. Didar-Ul; Bhuiyan, Mohammad Amir Hossain; Rume, Tanjena; Azam, Gausul

    2017-12-01

    Groundwater acts as a lifeline in the coastal regions to meet out the domestic, drinking, irrigational and industrial needs. To investigate the hydrogeochemical characteristics of groundwater and its suitability, twenty samples were collected from the shallow tubewells of study area having screen depth 21-54 m. The water quality assessment has been carried out by evaluating the physicochemical parameters such as temperature, pH, EC, TDS and major ions i.e., Na+, K+, Ca2+, Mg2+, Cl-, SO4 2-, NO3 -, HCO3 -. Results found that, the water is slightly alkaline and brackish in nature. The trends of cations and anions are Na+ > Ca2+ > Mg2+ > K+ and Cl- > HCO3 - > SO4 2- > NO3 -, respectively and Na-Cl-HCO3 is the dominant groundwater type. The analyzed samples were also characterized with different indices, diagram and permissible limit i.e., electric conductivity (EC), total dissolved solids (TDS), chloride content (Cl), soluble sodium percentage (SSP), sodium adsorption ratio (SAR), residual sodium carbonate (RSC), magnesium adsorption ratio (MAR), Kelley's ratio (KR), Wilcox diagram and USSL diagram, and results showed that groundwater are not suitable for drinking and irrigational use. The factors responsible for the geochemical characterization were also attempted by using standard plot and it was found that mixing of seawater with entrapped water plays a significant role in the study area.

  20. Hydrogeochemical Characteristics of Groundwater Highly Polluted with Nitrate in an Agricultural Area of Hongseong, Korea

    Directory of Open Access Journals (Sweden)

    Hyun-su Kim

    2016-08-01

    Full Text Available The hydrogeochemical characteristics of groundwater, in an area where widespread contamination by nitrate ( NO 3 − was anticipated, were studied using traditional geochemical investigation and multivariate statistical analysis. Widespread NO 3 − contamination as high as 67.2 mg/L as NO3–N was observed, and positively correlated with that for chemicals ( Cl − , major cations with surface origin. Principal component analysis (PCA revealed that three processes affected groundwater chemistry of the area: (1 leaching of pollutants from the ground surface; (2 reduction of NO 3 − in areas with low dissolved oxygen (DO; and (3 ingress of low NO 3 − deep groundwater. Five sample groups were identified from cluster analysis, and analysis of land use patterns around each group showed that fate and distribution of NO 3 − contamination were mainly controlled by surface topography and predominant land use type. The highest NO 3 − concentrations were associated with confined livestock feeding operations in hilly terrain areas, where infiltrating water also had high DO. Lower NO 3 − concentrations found in the lowland flat areas were thought to be due to either reducing conditions in rice paddies leading to N attenuation or drawing in of deep groundwater by pumping to meet agricultural needs during periods of low rainfall.

  1. Geological and hydrogeochemical research, tools for karst management in the north of the Caraş Gorges (Banat Mountains, Romania

    Directory of Open Access Journals (Sweden)

    Marius Vlaicu

    2010-01-01

    Full Text Available The karst geosystems functioning frequently implies very quick mass and energy transfers, which make them highly sensitive to any natural or anthropogenic disturbance. Therefore, the groundwater resources, threatened by agricultural and industrial pollution, should be carefully exploited, taking into account the intrinsic vulnerability of the region. This paper aims to present the results of the geological, geomorphological and hydrogeochemical studies carried out in the Banat Mountains (Romania, in order to widely assess and map the vulnerability of the most exposed karst aquifers. Following the principles of the EPIK method and using GIS, we were able to delineate upon degree 4 vulnerability classes (low, moderate, high, very high. Moreover, each unit has been assigned to a specific protection framework, comprising suitable management solutions, designed for environmental managers.

  2. Identifying and assessing human activity impacts on groundwater quality through hydrogeochemical anomalies and NO3-, NH4+, and COD contamination: a case study of the Liujiang River Basin, Hebei Province, P.R. China.

    Science.gov (United States)

    Peng, Cong; He, Jiang-Tao; Wang, Man-Li; Zhang, Zhen-Guo; Wang, Lei

    2018-02-01

    In the face of rapid economic development and increasing human activity, the deterioration of groundwater quality has seriously affected the safety of the groundwater supply in eastern China. Identifying and assessing the impact of human activities is key to finding solutions to this problem. This study is an effort to scientifically and systematically identify and assess the influence of human activities on groundwater based on irregularities in hydrochemical properties and water contamination, which are considered to directly result from anthropogenic activity. The combination of the hydrochemical anomaly identification (HAI) and the contaminant identification (CI) was proposed to identify the influence of human activities on groundwater quality. And the degree of abnormality was quantified by the background threshold value. The principal component analysis (PCA) and land use map were used to verify the reliability of the identification result. The final result show that the strong influence areas mainly distributed in the south of the basin and the affected indicators contained the major elements and NO 3 - , NH 4 + , COD. Impacts from anthropogenic activities can be divided into two types: mine drainage that disrupts natural water-rock interaction processes, agricultural cultivation, and sewage emissions that contribute to nitrate pollution.

  3. hydrogeochemical hydrogeochemical and biophysical

    African Journals Online (AJOL)

    eobe

    In situ measurements of temperature, pH, TDS, and EC were determined intrusively with appropriate probes. The Cat ions K+, Ca2+, Na2+ Mg2+ and heavy metals Zn,. Cu, Fe, Ba and Mn were determine using Atomic. Absorption Spectrometer (AAS) Model PYE Unicam SP. 2900. Other parameters were also determined by.

  4. Hydro-geophysical interpretation of fractured and karstified limestones reservoirs: A case study from Amdoun region (NW Tunisia) using electrical resistivity tomography, digital elevation model (DEM) and hydro-geochemical approaches

    Science.gov (United States)

    Redhaounia, Belgacem; Aktarakçi, Hasan; Ilondo, Batobo Ountsche; Gabtni, Hakim; Khomsi, Sami; Bédir, Mourad

    2015-12-01

    Groundwater from fractures and karst in limestone rocks is an important source of drinking water in the semi-arid climatic environment of North-Western Tunisia where cool and rainy seasons alternate with hot dry seasons. Due to varying climatic conditions and anthropogenic interventions the fractured limestone aquifer systems (Abiod and Boudabbous/El Gueria Formations) tend to be complex. The lack of data on the fractured and karstified aquifers in Amdoun region (NW Tunisia) to establish the hydrogeological potential between different rock formations of Upper Cretaceous and Lower Eocene has often discouraged researchers from attempting to model such aquifers. On the SE flank of the Jebel Sabbah anticline, Electrical Resistivity Tomography Data were collected along three different lines of 315 m of length each. The expected vertical penetration depth was 60 m. This hydro-geophysical investigation consisting of geological, structural, and geo-morphological studies, has demonstrated that groundwater in the carbonate rocks, in Amdoun area, occur in fracture zones and weathered parts of the rocks in the karst aquifers. The hydrochemical data (major ion geochemistry) indicate that these groundwaters are characterized by the dominance a Ca-Mg-HCO3 water type. Geochemical pattern is mainly controlled by the dissolution of carbonate minerals. Generally, TDS increases from the Amdoun Monts towards the discharge area (53 < TDS<332 mg l-1). These results are assessed using numerous geophysical data such as ERT imaging and geological knowledge. Finally, we show how these results could be used to improve the management of karst groundwater resources in Amdoun (NW Tunisia) complex terrain.

  5. Hydrogeochemical investigation of six geothermal sites in Honduras, Central America

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.E.; Truesdell, A.H.; Grigsby, C.O.; Janik, C.J.; Shevenell, L.A.; Paredes, J.R.; Gutierrez, J.W.; Trujillo, Jr.; Counce, D.A.

    1987-06-01

    We conducted detailed hydrogeochemical investigations at six geothermal sites in western Honduras: Azacualpa, El Olivar, Pavana, Platanares, Sambo Creek, and San Ignacio. None of the sites is associated with Quaternary silicic volcanism, although El Olivar lies adjacent to a small Quaternary basalt field and Pavana is part of a belt of hot spring activity parallel to and 35 km east of the Central American volcanic arc. None of the sites contains acid-sulfate waters indicative of vapor-dominated conditions. Thermal fluids are characterized by pH between 7 and 10, Cl<125 mg/l, HCO/sub 3/>Cl, SO/sub 4/greater than or equal toCl, Bless than or equal to17 mg/l, Liless than or equal to4 mg/l, and Asless than or equal to1.25 mg/l. Stable isotope analyses of the water show that recharge to the geothermal systems generally occurs from areas of higher elevation adjacent to the sites. Tritium contents of apparently undiluted thermal fluids range from 0 to 0.4 T.U., indicating residence times of fluids in the systems of more than 500 y. Various geochemical indicators show that mixing of hot and cold end-member fluids occurs in the system at Platanares and, to a lesser degree, in the systems at San Ignacio and Azacualpa. No mixing is apparent in the fluids discharging at Pavana, Sambo Creek, or El Olivar. Boiling is the dominant process responsible for subtle geochemical variations at Azacualpa and, possibly, San Ignacio. Our best estimates of subsurface reservoir temperatures are 225/sup 0/C at Platanares, 190/sup 0/C at San Ignacio, 185/sup 0/C at Azacualpa, 155/sup 0/C at Sambo Creek, 150/sup 0/C at Pavana, and 120/sup 0/C at El Olivar. The estimated power output of the three hottest sites is 45 thermal megawatts at Platanares, 14 thermal megawatts at San Ignacio, and 13 thermal megawatts at Azacualpa.

  6. Hydro-geochemical paths of multi-layer groundwater system in coal mining regions - Using multivariate statistics and geochemical modeling approaches.

    Science.gov (United States)

    Liu, Pu; Hoth, Nils; Drebenstedt, Carsten; Sun, Yajun; Xu, Zhimin

    2017-12-01

    Groundwater is an important drinking water resource that requires protection in North China. Coal mining industry in the area may influence the water quality evolution. To provide primary characterization of the hydrogeochemical processes and paths that control the water quality evolution, a complex multi-layer groundwater system in a coal mining area is investigated. Multivariate statistical methods involving hierarchical cluster analysis (HCA) and principal component analysis (PCA) are applied, 6 zones and 3 new principal components are classified as major reaction zones and reaction factors. By integrating HCA and PCA with hydrogeochemical correlations analysis, potential phases, reactions and connections between various zones are presented. Carbonates minerals, gypsum, clay minerals as well as atmosphere gases - CO 2 , H 2 O and NH 3 are recognized as major reactants. Mixtures, evaporation, dissolution/precipitation of minerals and cation exchange are potential reactions. Inverse modeling is finally used, and it verifies the detailed processes and diverse paths. Consequently, 4 major paths are found controlling the variations of groundwater chemical properties. Shallow and deep groundwater is connected primarily by the flow of deep groundwater up through fractures and faults into the shallow aquifers. Mining does not impact the underlying aquifers that represent the most critical groundwater resource. But controls should be taken to block the mixing processes from highly polluted mine water. The paper highlights the complex hydrogeochemical evolution of a multi-layer groundwater system under mining impact, which could be applied to further groundwater quality management in the study area, as well as most of the other coalfields in North China. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Hydrogeochemical and Isotopic Study of Groundwaters from the Gañuelas-Mazarrón Tertiary Basin (Murcia, Spain); Estudio Hidrogeoquímico e Isotópico de las Aguas de la Cuenca Terciaria de Gañuelas-Mazarrón (Murcia, España)

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigo-Naharro, J.; Delgado, A.; Clemente-Jul, C.; Pérez del Villar, L.

    2015-07-01

    The hydrogeochemical characterisation of groundwaters from the Gañuelas-Mazarrón Tertiary Basin included: i) to establish the different hydrofacies present in the basin; ii) to perform a cluster analysis in order to reduce the water samples, grouping them according to their physicochemical characteristics; and iii) to determine the most relevant ion ratios for understanding the water/ rock interaction processes that regulate the main features and evolution of groundwaters. It has also been discussed the origin and concentration of the minor and trace elements to evaluate the capability of groundwaters to transport heavy elements, toxic or innocuous, towards the surface, thus determining their suitability for human consumption. Besides, the hydrogeochemical modeling has allowed determining the degree of groundwaters saturation with respect to the most representative mineral phases of the aquifers, which, in turn, it has been used to calculate their theoretical temperature in depth. The isotopic characterisation of groundwaters has included the isotopic signatures of the stable (δ18O, δ2H, δ13C-DIC, δ34S(SO4 2-) and δ18O(SO4 2-)) and radioactive (238U, 234U and 226Ra) isotopes. The first have been used to distinguish the groundwaters origin, as well as the origin of the dissolved C and SO4 2-. The radioactive isotopes have been used to determine the water/rock interaction processes involving 238U radioactive series, as well as to explain the origin of the dissolved 222Rn in groundwaters. The most important hydrogeochemical results obtained from groundwaters are: i) a large variety of hydrofacies is represented in them, corroborated by the cluster analysis; ii) they are not suitable for human consumption; iii) they have remained, apparently, over-saturated with respect to calcite and aragonite, and under-saturated with respect to gypsum, anhydrite and halite, over time; iv) they present theoretical temperatures in depth much higher than in the surface; v) they

  8. Assessment of impacts by open-loop geothermal system operation on hydrogeochemical properties in riverside aquifer

    Science.gov (United States)

    Koh, E. H.; Park, B. H.; Park, J.; Lee, K. K.; Lee, S. Y.

    2016-12-01

    Open-loop ground source heat pump (GSHP) utilizes groundwater in the subsurface, which maintains constant temperature regardless of seasonal changes, to be circulated through a heat pump system coupled with pumping and injection wells. During operation of the open-loop GSHP facilities, the hydrogeochemical properties of the subsurface aquifer can be altered by contacting with atmospheric air, changing temperature and pressure. Such changes in the water quality can impede energy efficiency of the open-loop GSHP. Therefore, it is important to monitor the groundwater components regularly before and after the operation of GSHP. In the riverside area of the Yangpyeong, South Korea, an open-loop GSHP has been installed for a test research, which has objectives to improve energy efficiency of the open-loop GSHP facilities and to evaluate environmental changes caused by the GSHP operation. Because the study area is located near the Han River, it is necessary to assess hydrochemical changes of groundwater resulted by the open-loop GSHP operation in consideration of interaction between the river water and groundwater. Periodic monitoring of groundwater and river water quality had been conducted from Jan., 2014 to Apr., 2016 including the operation periods of the open-loop GSHP after Apr., 2015. As the result of the open-loop GSHP operation, there were no abrupt changes in groundwater quality parameters except an increase in Cl- concentration and decrease in DO concentration over the study area. The enriched Cl- concentration was observed in both river water and groundwater based on estimation of effects by eutrophication in the river. Lowering DO concentration throughout the study area was affected by re-injection of the pumped groundwater with depleted DO during the GSHP operation with an increase of Fe2+ concentration. Such changes in the water chemistry were evaluated not to give a harmful influence on the long-term operation of the GSHP system in the study area.

  9. Hydrogeochemical characterization and Natural Background Levels in urbanized areas: Milan Metropolitan area (Northern Italy)

    Science.gov (United States)

    De Caro, Mattia; Crosta, Giovanni B.; Frattini, Paolo

    2017-04-01

    Although aquifers in densely populated and industrialized areas are extremely valuable and sensitive to contamination, an estimate of the groundwater quality status relative to baseline conditions is lacking for many of them. This paper provides a hydrogeochemical characterization of the groundwater in the Milan metropolitan area, one of the most densely populated areas in Europe. First, a conceptual model of the study area based on the analysis of the spatial distribution of natural chemical species and indicator contaminants is presented. The hydrochemical facies of the study area depend on the lithology of catchments drained by the main contributing rivers and on the aquifer settings. The anthropogenic influence on the groundwater quality of superficial aquifers is studied by means of probability plots, concentration versus depth plots and spatial-temporal plots for nitrate, sulfate and chloride. These allow differentiation of contaminated superficial aquifers from deep confined aquifers with baseline water quality. Natural Background Levels (NBL) of selected species (Cl, Na, NH4, SO4, NO3, As, Fe, Mn and Zn) are estimated by means of the pre-selection (PS) and the component separation (CS) statistical approaches. The NBLs depend on hydrogeological settings of the study area; sodium, chloride, sulfate and zinc NBL values never exceed the environmental water quality standards. NBL values of ammonium, iron, arsenic and manganese exceed the environmental water quality standards in the anaerobic portion of the aquifers. On the basis of observations, a set of criteria and precautions are suggested for adoption with both PS and CS methods in the aquifer characterization of highly urbanized areas.

  10. Hydrogeochemical evaluation. Preliminary site description Laxemar subarea - version 1.2

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-04-15

    Siting studies for SKB's programme of deep geological disposal of nuclear fuel waste currently involves the investigation of two locations, Simpevarp and Forsmark, on the eastern coast of Sweden to determine their geological, hydrogeochemical and hydrogeological characteristics. Present work completed has resulted in Model version 1.2 for Laxemar subarea which represents the third evaluation of the available Simpevarp area groundwater analytical data collected up to November, 2004. Model version 1.2 focusses on improving the methodology and tools used for evaluating the hydrochemistry combined with a sensitivity and uncertainty analysis of the available data. The major goal has been to consolidate groundwater geochemical understanding and the models used at the site. The complex groundwater evolution and patterns at Simpevarp 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 Laxemar/Simpevarp are considered local and extend down to depths of around 600-1,000 m depending on local topography. Close to the Baltic Sea coastline where topographical variation is small, groundwater flow penetration to depth will subsequently be less marked. In contrast, the Laxemar subarea is characterised by higher topography resulting in a much more dynamic groundwater circulation which appears to extend to 1,000 m depth in the vicinity of borehole KLX02. The marked differences in the groundwater flow regimes between the Laxemar and Simpevarp are reflected in the groundwater chemistry where four major

  11. Hydrogeological pre-modelling exercises. Assessment of impact of the Aespoe Hard Rock Laboratory. Sensitivities of palaeo-hydrogeology. Development of a local near-surface Hydro-DFN for KLX09B-F. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, Lee; Jackson, Peter; Joyce, Steve; Roberts, David; Shevelan, John; Swift, Ben (Serco Assurance, Harwell (GB)); Gylling, Bjoern; Marsic, Niko (Kemakta Konsult AB, Stockholm (SE)); Hermanson, Jan; Oehman, Johan (Golders Associates (SE))

    2007-12-15

    Numerical modelling has been used to investigate the potential impact of the Aespoe HRL on regional groundwater flow and hydro-geochemistry in the Laxemar study area. The numerical models have been adapted for this application from the ones use in the site-descriptive modelling (SDM) and SR-Can assessment modelling based on Laxemar version 1.2. In order to test the robustness of the simulation results, sensitivities were studied with respect to different flow boundary conditions and the hydraulic properties of the Quaternary deposits, particularly those beneath the sea around the Aespoe island. The simulations show that the Aespoe HRL has a local effect on the groundwater situation. Typically, in the simulations, the rock under the Aespoe island, the bays around it and the Aevroe area (mainly western part of the islands of Aevroe, Mjaelen and Haaloe) are influenced. In the sensitivity study, visualisations of the drawdown caused by the HRL tunnel system show small differences in the results for head versus flux top boundary conditions, little sensitivity to a change in the surface infiltration rate, but most sensitivity to the contact between the sea and the bedrock beneath the seabed sediments. For all simulation cases considered, results suggest that the Aespoe HRL has not been in operation sufficiently long to have affected the chemistry of samples collected at Laxemar and Simpevarp, though there is some possibility that Aevroe samples have been altered, at least for boreholes in the western part of Aevroe, Mjaelen and Haaloe. The distribution of flow and discharge areas around the bay at Aespoe is clearly affected by the HRL for all cases. Using the drawdown in percussion drilled boreholes around Aespoe as an interference test suggests that there is a partial reduction in the hydraulic contact between the sea and the groundwater system in the bedrock beneath. It is recommended that the conclusions about appropriate hydraulic properties for Quaternary sediments

  12. Identification of the hydrogeochemical processes and assessment of groundwater quality using classic integrated geochemical methods in the Southeastern part of Ordos basin, China.

    Science.gov (United States)

    Yang, Qingchun; Li, Zijun; Ma, Hongyun; Wang, Luchen; Martín, Jordi Delgado

    2016-11-01

    Insufficient understanding of the hydrogeochemistry of aquifers makes it necessary to conduct a preliminary water quality assessment in the southern region of Ordos Basin, an arid area in the world. In this paper, the major ions of groundwater have been studied aiming at evaluating the hydrogeochemical processes that probably affect the groundwater quality using 150 samples collected in 2015. The two prevalent hydrochemical facies, HCO3Mg·Na·Ca and HCO3Mg·Ca·Na type water, have been identified based on the hydrochemical analysis from Piper trilinear diagram. Compositional relations have been used to assess the origin of solutes and confirm the predominant hydrogeochemical processes responsible for the various ions in the groundwater. The results show that the ions are derived from leaching effect, evaporation and condensation, cation exchange, mixing effect and human activities. Finally groundwater quality was assessed with single factor and set pair methods, the results indicate that groundwater quality in the study region is generally poor in terms of standard of national groundwater quality. The results obtained in this study will be useful to understand the groundwater quality status for effective management and utilization of the groundwater resource. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Hydrogeochemical evaluation for Simpevarp model version 1.2. Preliminary site description of the Simpevarp area

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-12-01

    Siting studies for SKB's programme of deep geological disposal of nuclear fuel waste currently involves the investigation of two locations, Simpevarp and Forsmark, 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 Simpevarp groundwater analytical data collected up to April, 2004. The deepest fracture groundwater samples with sufficient analytical data reflected depths down to 1.7 km. Model version 1.2 focusses on geochemical and mixing processes affecting the groundwater composition in the uppermost part of the bedrock, down to repository levels, and eventually extending to 1000 m depth. The groundwater flow regimes at Laxemar/Simpevarp are considered local and extend down to depths of around 600-1000 m depending on local topography. The marked differences in the groundwater flow regimes between Laxemar and Simpevarp are reflected in the groundwater chemistry where four major hydrochemical groups of groundwaters (types A-D) have been identified: TYPE A: This type comprises dilute groundwaters (< 1000 mg/L Cl; 0.5-2.0 g/L TDS) of Na-HCO{sub 3} type present at shallow (<200 m) depths at Simpevarp, but at greater depths (0-900 m) at Laxemar. At both localities the groundwaters are marginally oxidising close to the surface, but otherwise reducing. Main reactions involve weathering, ion exchange (Ca, Mg), surface complexation, and dissolution of calcite. Redox reactions include precipitation of Fe-oxyhydroxides and some microbially mediated reactions (SRB). Meteoric recharge water is mainly present at Laxemar whilst at Simpevarp potential mixing of recharge meteoric water and a modern sea component is observed. Localised mixing of meteoric water with deeper saline groundwaters is indicated at both Laxemar and Simpevarp. TYPE B: This type comprises brackish groundwaters (1000-6000 mg/L Cl; 5-10 g/L TDS) present at

  14. Description of regolith at Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Sohlenius, Gustav; Hedenstroem, Anna (Geological Survey of Sweden (SGU), Uppsala (Sweden))

    2008-11-15

    This report compiles all known available information regarding the regolith in the Laxemar-Simpevarp regional model area. Regolith refers to the loose deposits overlying the bedrock. In the Laxemar-Simpevarp area, all known regolith was deposited during the Quaternary period and is consequently often referred to as Quaternary deposits (QD). In the terrestrial areas the uppermost part of the regolith, which has been affected by climate and vegetation, is referred to as soil. The geographical and stratigraphical distributions of the regolith have been used to construct a model showing the distribution of regolith depths in the whole model area. The stratigraphical units shown in the regolith depth and stratigraphy model have been characterised with respect to physical and chemical properties. Most of the data used for that characterisation have been obtained from the site investigation but some data were taken from the literature. All QD in the Laxemar area have most probably been deposited during or after the latest deglaciation. The ice sheet in the area moved from the north-west during the latest ice age. The Baltic Sea completely covered the investigated area after the latest deglaciation c 12,000 BC. Land uplift was fastest during the first few thousand years following the deglaciation and has subsequently decreased to the present value of 1 mm/year. Older QD have been eroded in areas exposed to waves and currents and the material has later been redeposited. Fine-grained sediments have been deposited on the floor of bays and in other sheltered positions. Peat has accumulated in many of the wetlands situated in topographically low positions. The groundwater table in many of the former wetlands has been artificially lowered to obtain land for forestry and agriculture, which has caused the peat to partly or completely oxidise. As land uplift proceeds, some new areas are being subjected to erosion at the same time as other new areas are becoming lakes and sheltered bays where fine-grained sediments can accumulate. The distribution of QD's on both land and sea areas is shown on a map over the whole Laxemar- Simpevarp regional model area. Data obtained from several investigations have been used to produce that map. The accuracy of the map therefore varies and the most detailed information was obtained from the central part of the model area. The geographical distribution and depth of the QD is largely determined by the topography of the underlying bedrock. Areas with exposed bedrock and a thin till cover dominate the whole regional model area, including the sea floor. These areas are crossed by a number of fissure valleys where the regolith cover is considerably thicker. Glacial clay with a thin cover of sand is the dominating surface deposit in the valleys on the sea floor. In the bays and land areas, the valleys are dominated by clay gyttja, which at many locations in the terrestrial areas is covered by a thin layer of peat. There are several glaciofluvial deposits, with a north strike, in the investigated area. The Tuna esker in the western part of the model area is the largest of these deposits. In a morphological sense, that esker is the most significant QD in the model area. In certain areas the till has a more coherent distribution than in the area in general. These areas are characterised by hummocks, which are probably not due to the morphology of the underlying bedrock. The properties of soils have been classified at sites representing ten land classes. These results were used together with the QD map and other geographical information to produce a soil-type map over the terrestrial part of the model area. Podsol, Leptosol and Regosol are the most commonly occurring soil types in the area. Wetlands and areas used as arable land, i.e. for cultivation of crops, are to a large extent covered by different types of Histosol. Most data showing the total depth of the regolith cover were obtained from geophysical investigations. The stratigraphical distribution of QD was obtained from drilling and excavations. The results show that the stratigraphical distribution of QD in the investigated area is rather uniform. Till is the oldest QD in the area, and is subsequently resting directly upon the bedrock surface. The till in the valleys is often overlain by glacial clay, which in many valleys is overlain by a thin layer of sand followed by clay gyttja and peat. The most common QD have been analysed with respect to grain size distribution. Porosity and density has been calculated for some of the QD. Data from the literature have been used for the QD when site-specific data necessary for calculating these values are not available. The till has a low content of fine material and is dominated by sand and gravel. In some of the valleys the till underlying the clay is surprisingly well sorted with respect to grain size. The contents of elements in the regolith from the Laxemar area are close to the Swedish averages.

  15. 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

  16. 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 mineral has a central role in the forming of today's hydrochemistry in surface systems, and probably also on the composition of the dilute, non-brackish, groundwater in the upper parts of the fractured bedrock. The rich supply of calcium and the high alkalinity affects the structure of the whole ecosystem, for example by forming the oligotrophic hardwater lakes which are characteristic for the area. One major issue in the report is if there can be found any indications on deep groundwater discharge in the surface system. According to observations in surface water and shallow groundwater, and to the hydrological/hydrochemical conceptual model, there is probably no ongoing deep discharge into the freshwater surface system. In restricted areas there are, however, indications that relict marine remnants, which also includes deep saline signatures, prevail in the groundwater at relatively shallow depths in the Quaternary deposits, but not reach the surface due to the downwards directed groundwater flow pattern that generally prevail in the area. This hydrochemical pattern could according to the conceptual model probably be explained by influence from marine remnants formed under a previous hydrological regime and these signatures are preserved because of stagnant conditions in some areas

  17. 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 the lakes are dominated by species resistant to low oxygen concentrations, mainly due to poor oxygen conditions during the winter. The streams in Forsmark are all very small, and long stretches of the streams are dry during summer. The downstream parts of some of the streams may function as passages for migrating fish, and extensive spawning migration between the sea and a downstream lake has been observed. Human activities in the area have affected the limnic ecosystem, and large parts of the streams in the Forsmark area consist of man-made ditches. Moreover, one of the lakes has been lowered and one has been divided into two basins. The ecosystem carbon models for the Forsmark area show that the lakes that contain a microbial mat have larger primary production than respiration, and thus show a positive net ecosystem production (NEP). In lakes that lack a microbial mat, respiration is similar in magnitude as primary production and net ecosystem production is close to zero. Carbon mass balance models for the Forsmark lakes indicate, in accordance with the ecosystem models, that the larger lakes (with a microbial mat) in the area have a positive NEP. However, in contrast to the ecosystem models, the mass balance models indicate that the smaller lakes in the area have negative NEP, regardless of the occurrence of a microbial mat. A low proportion (7-10%) of the carbon incorporated into primary producers in the lake is transported upwards in the food web, and instead most carbon is consumed by bacteria in the form of DOC and POC. The mass balances for a number of elements in Forsmark lakes show that the proportions of different fluxes to and from the lakes are dependent on lake size and position in the catchment, but also on the specific properties of the different elements. The Laxemar-Simpevarp lakes are small and all but one are characterized as brown-water lakes. The lakes have moderate phosphorus concentrations, whereas the concentrations of nitrogen and dissolved organic carbon tend to be high. Because of the brownish water, light penetration is poor and the depth of the photic zone is generally small. In accordance, macrophyte coverage in the lakes is small and biota is dominated by heterotrophic organisms, particularly bacteria. Perch is the predominant fish species in numbers, as well as in weight, in the lakes in the area. Most of the streams in the Laxemar-Simpevarp area are small with mostly calm or slowly flowing water and many of the streams have dry sections in the summer. Most lakes in the Laxemar-Simpevarp area are affected by human activities; the water level in most lakes has been lowered, and one lake, Soeraamagasinet, was originally a sea bay but was dammed in order to ensure freshwater reserves to the nuclear power plant. Water is pumped from Laxemaraan to Soeraamagasinet in order to maintain the available water storage in the lake.

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

    Energy Technology Data Exchange (ETDEWEB)

    Troejbom, Mats (Mopelikan, Norrtaelje (Sweden)); Soederbaeck, Bjoern; Kalinowski, Birgitta (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden))

    2008-10-15

    Based on a mathematical/statistical approach, a large number of visualisations and models reflect the hydrochemistry of the Laxemar-Simpevarp area, with the intention of providing an understanding of important processes and factors that affect the hydrochemistry of the surface systems. In order to widen the perspective, all data from Laxemar stage 2.3, 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 provide a general understanding of the site and to explain observed overall patterns and anomalies, and ultimately to present a conceptual model that explains the present hydrochemistry of the surface system in the light of the past. The report may also serve 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 topography in the Laxemar-Simpevarp area is characterised by elevated areas covered by thin or no Quaternary deposits, intersected by deep fissure valleys filled with thick sediments. This topography, in combination with the withdrawal of the Baltic Sea due to isostatic land uplift, are two important factors determining the hydrochemistry of the Laxemar-Simpevarp area. Furthermore, marine remnants in the Quaternary deposits influence the hydrochemistry in areas at low elevation close to the coast, whereas higher-lying areas are mostly influenced by atmospheric deposition and weathering processes. The vegetation cover has also great impact on the hydrochemistry of the surface system. Degradation of biogenic carbon generates large numbers of H+ ions, which drive weathering processes in the Quaternary deposits as well as in the upper parts of the bedrock. The present situation in the surface system is a consequence of the palaeohydrological past. In higher elevated areas, meteoric recharge has a great influence on the observed hydrochemistry, which is usually characterised by dilute fresh waters of low ionic strength. In lower areas close to the coast, there are indications of ongoing flushing of marine relicts since the area was covered by sea water. At most locations in the Laxemar-Simpevarp area, this flushing is more or less completed and concentrations of marine ions may be explained by deposition and anthropogenic sources. As much as 2/3 of the Cl input to the surface system has been estimated to originate from anthropogenic sources as road salt. One important question in the hydrochemical evaluation is whether there are any indications of deep groundwater discharge in the surface system. It can be concluded from observations in shallow groundwater that deep groundwater signatures are present in the Quaternary deposits in potential deep discharge areas beneath lakes and brackish bays. On land, no deep signatures have been detected neither in surface water nor in groundwater, which indicates that shallow meteoric recharge/discharge patterns dominate and that potential regional deep discharge is too dilute to be detected in surface water

  19. Identification of the Hydrogeochemical Processes in Groundwater Using Classic Integrated Geochemical Methods and Geostatistical Techniques, in Amol-Babol Plain, Iran

    Directory of Open Access Journals (Sweden)

    Tahoora Sheikhy Narany

    2014-01-01

    Full Text Available Hydrogeochemical investigations had been carried out at the Amol-Babol Plain in the north of Iran. Geochemical processes and factors controlling the groundwater chemistry are identified based on the combination of classic geochemical methods with geographic information system (GIS and geostatistical techniques. The results of the ionic ratios and Gibbs plots show that water rock interaction mechanisms, followed by cation exchange, and dissolution of carbonate and silicate minerals have influenced the groundwater chemistry in the study area. The hydrogeochemical characteristics of groundwater show a shift from low mineralized Ca-HCO3, Ca-Na-HCO3, and Ca-Cl water types to high mineralized Na-Cl water type. Three classes, namely, C1, C2, and C3, have been classified using cluster analysis. The spatial distribution maps of Na+/Cl−, Mg2+/Ca2+, and Cl-/HCO3- ratios and electrical conductivity values indicate that the carbonate and weathering of silicate minerals played a significant role in the groundwater chemistry on the southern and western sides of the plain. However, salinization process had increased due to the influence of the evaporation-precipitation process towards the north-eastern side of the study area.

  20. Microbial diversity and hydrogeochemical characteristics of natural CO2-rich springs in Korea

    Science.gov (United States)

    Ko, D.; Do, H. K.; Yun, S. T.; Chung, H.

    2016-12-01

    Natural CO2-rich springs are unique ecosystems where microbial communities are adapted to extreme conditions including low pH. We analyzed bacterial and archaeal community composition and hydrogeochemical features in two different natural CO2-rich springs located in the south-eastern part of Korea. Analyses of hydrogeochemical characteristics and 16S rRNA gene pyrosequencing of bacteria and archaea showed remarkable distinction between the two CO2-rich springs, Hansil (HS) and Chosukol (CS). Both springs were weakly acidic (pH 5.1 to 6.2), but the electrical conductivity and the concentration of major ions such as Ca2+, Mg2+, Na+, K+, Fe+ and HCO3- were significantly higher in HS spring than in CS spring. Among the bacterial communities, the family of Gallionellaceae (ferro-oxidant), a member of the order Gallionellales was predominant in HS spring, occupying 72% of the total abundance. On the other hand, in CS spring, Oxalobacteraceae (chemolithotrophs) and Comamonadaceae (chemoorganotrophs), the families of the order Burkholderiales were predominant and their relative abundance was 65 and 21%, respectively. Among the archaeal communities, the phylum Thaumarchaeota was predominant in CS spring, its relative abundance being 72%. In HS spring, the phyla Thaumarchaeota, Euryarchaeota and Crenarchaeota were relatively evenly distributed. Our results suggest that the significant differences in bacterial and archaeal communities of each CO2-rich spring are closely related to hydrogeochemical characteristics, and also those were in accordance with the geological formation process of CO2-rich springs.

  1. Hydrogeochemical investigation of groundwater in Jericho area in the Jordan Valley, West Bank, Palestine

    Science.gov (United States)

    Da'as, Ammar; Walraevens, Kristine

    2013-06-01

    Water resources in the Middle East, particularly in Palestine, are extremely scarce and costly. The Jordan Valley is a fertile productive region, described as the food basket of Palestine. Groundwater originating from the Quaternary Aquifer System forms the main water resource in the Jordan Valley. However, the quality of this groundwater is threatened mainly by the high chloride concentration. The most representative area of the Jordan Valley is Jericho area, which was chosen to be the study area. The study area (65 km2) is almost a flat area with a gentle decline towards the east. It is the lowest land on earth with ground levels reaching 400 meters below sea level (mbsl) near the Dead Sea shores. The Quaternary Aquifer System in the study area could be divided into an upper alluvial layer with thickness varying from 40 to 150 m and a lower low-permeable Lisan layer, which crops out in the eastern part of the study area with thickness over 200 m. Hydrogeochemical investigation reveals that the water is generally earth alkaline with higher content of earth alkalis and prevailing chloride. According to Stuyfzand (1986) and Piper's (1944) classification systems, water type in the Alluvial Aquifer varies from fresh hard CaMgHCO3 or MgCaHCO3 water in the west and northwest to brackish very-hard MgNaCl or NaMgCl in the middle. In the east, the water becomes brackish-salt extremely-hard MgNaCl or NaCl. Groundwater quality is deteriorating (increase in salinity) spatially towards the east and vertically with increasing depth (when nearing the Lisan Formation). As an indication of groundwater salinity, total dissolved solids show some variability with time over the last 21 years (1983-2004). In short-time scale, there are high seasonal and yearly fluctuations with regard to salinity, specifically in Cl- and SO42- contents. Spring water from the Upper Cenomanian Aquifer (CaHCO3) represents the fresh end member, while Rift Valley Brines (RVB-CaNaCl) and Dead Sea Brines (DSB

  2. Geochemical tracing and hydrogeochemical modelling of water-rock interactions during salinization of alluvial groundwater (Upper Rhine Valley, France)

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Y., E-mail: yann.lucas@eost.u-strasbg.fr [Universite de Strasbourg et CNRS, Laboratoire d' Hydrologie et de Geochimie de Strasbourg, Ecole et Observatoire des Sciences de la Terre, 1, rue Blessig, 67084 Strasbourg Cedex (France); Schmitt, A.D., E-mail: anne-desiree.schmitt@univ-fcomte.fr [Universite de Strasbourg et CNRS, Laboratoire d' Hydrologie et de Geochimie de Strasbourg, Ecole et Observatoire des Sciences de la Terre, 1, rue Blessig, 67084 Strasbourg Cedex (France)] [Universite de Franche-Comte et CNRS-UMR 6249, Chrono-Environnement, 16, Route de Gray, 25030 Besancon Cedex (France); Chabaux, F., E-mail: francois.chabaux@eost.u-strasbg.fr [Universite de Strasbourg et CNRS, Laboratoire d' Hydrologie et de Geochimie de Strasbourg, Ecole et Observatoire des Sciences de la Terre, 1, rue Blessig, 67084 Strasbourg Cedex (France); Clement, A.; Fritz, B. [Universite de Strasbourg et CNRS, Laboratoire d' Hydrologie et de Geochimie de Strasbourg, Ecole et Observatoire des Sciences de la Terre, 1, rue Blessig, 67084 Strasbourg Cedex (France); Elsass, Ph. [BRGM, GEODERIS, 1, rue Claude Chappe, 57070 Metz (France); Durand, S. [Universite de Strasbourg et CNRS, Laboratoire d' Hydrologie et de Geochimie de Strasbourg, Ecole et Observatoire des Sciences de la Terre, 1, rue Blessig, 67084 Strasbourg Cedex (France)

    2010-11-15

    Research highlights: {yields} Major and trace elements along with strontium and uranium isotopic ratios show that groundwater geochemical characteristics along the saline plumes cannot reflect a conservative mixing. {yields} A coupled hydrogeochemical model demonstrates that cationic exchange between alkalis from polluted waters and alkaline-earth elements from montmorillonite present in the host rock of the aquifer is the primary process. {yields} The model requires only a small amount of montmorillonite. {yields} It is necessary to consider the pollution history to explain the important chloride, sodium and calcium concentration modifications. {yields} The model shows that the rapidity of the cationic exchange reactions insures a reversibility of the cation fixation on clays in the aquifer. - Abstract: In the southern Upper Rhine Valley, groundwater has undergone intensive saline pollution caused by the infiltration of mining brines, a consequence of potash extraction carried out during the 20th century. Major and trace elements along with Sr and U isotopic ratios show that groundwater geochemical characteristics along the saline plumes cannot reflect conservative mixing between saline waters resulting from the dissolution of waste heaps and one or more unpolluted end-members. The results imply the occurrence of interactions between host rocks and polluted waters, and they suggest that cationic exchange mechanisms are the primary controlling process. A coupled hydrogeochemical model has been developed with the numerical code KIRMAT, which demonstrates that cationic exchange between alkalis from polluted waters and alkaline-earth elements from montmorillonite present in the host rock of the aquifer is the primary process controlling the geochemical evolution of the groundwater. The model requires only a small amount of montmorillonite (between 0.75% and 2.25%), which is in agreement with the observed mineralogical composition of the aquifer. The model also proves

  3. Hydrogeochemical characterization of groundwater of peninsular Indian region using multivariate statistical techniques

    Science.gov (United States)

    Jacintha, T. German Amali; Rawat, Kishan Singh; Mishra, Anoop; Singh, Sudhir Kumar

    2017-10-01

    Groundwater quality of Chennai, Tamil Nadu (India) has been assessed during different seasons of year 2012. Three physical (pH, EC, and TDS) and four chemical parameters (Ca2+, Cl-, TH, Mg2+ and SO4 2-) from 18 bore wells were assessed. The results showed that pH of majority of groundwater samples indicates a slightly basic condition (7.99post-monsoon and 8.35pre-monsoon). TH was slightly hard [322.11 mg/lpre-monsoon, 299.37 mg/lpost-monsoon but lies under World Health Organization (WHO) upper limit]. EC, TDS, Ca2+ and Mg2+ concentrations were under WHO permissible limit during post-monsoon (1503.42 μS/cm, 1009.37, 66.58 and 32.42 mg/l respectively) and pre-monsoon (1371.58 μS/cm, 946.84, 71.79 and 34.79 mg/l, respectively). EC shows a good correlation with SO4 2- ( R 2 = 0.59pre-monsoon, 0.77post-monsoon) which indicates that SO4 2- plays a major role in EC of ground water of bore wells. SO4 2- has also showed positive correlations with TDS ( R 2 = 0.84pre-monsoon, 0.95post-monsoon) and TH ( R 2 = 0.70pre-monsoon, 0.75post-monsoon). The principal component analysis (PCA)/factor analysis (FA) was carried out; Factor1 explains 59.154 and 69.278 % of the total variance during pre- and post-monsoon, respectively, with a strong positive loading on Ca2+, Mg2+, SO4 2-, TDS and a negative loading on pH. Factor2 accounts for 13.94 and 14.22 % of the total variance during pre- and post-monsoon, respectively, and was characterized by strong positive loading of only pH and poor/negative loading of EC, Ca2+, Mg2+, SO4 2-, TDS and TH during pre- and post-monsoon. We recommend routine monitoring and thorough treatment before consumption. Further, this study has demonstrated the effectiveness of PCA/FA to assess the hydrogeochemical processes governing the groundwater chemistry in the area.

  4. Hydrogeochemical characteristics and assessment of water quality in the Al-Saad Lake, Abha Saudi Arabia

    Science.gov (United States)

    Mallick, Javed

    2017-10-01

    Hydrogeochemical characteristics and assessment of water quality investigations have been carried out at Abha, located in Saudi Arabia, where Al-Saad Lake represents a rare example of natural endorheic lake. The ecosystem within and around the Al-Saad Lake including catchment area is of great social, cultural, aesthetic, environmental and economic values to Abha. Sampling and experiments of lake water has been carried out with the aim of characterizing the main physico-chemical parameters, such as DO, EC, TDS, Mg2+, Ca2+, Na+, K+, SO4 2-, Cl-, HCO3, NO3 - and F- concentration. The ordinary kriging (OK) method was used to produce the spatial patterns of water quality. The Result of DO (mean 5.38 mg/L) trend in Al-Saad Lake is not very encouraging as majority of the lake area is under DO stress or marginally above it. So, proper management strategies are needed to be formulated to protect flora and fauna of the lake. Furthermore, the chemical analysis results show the abundance of the major cations in the order Mg2+ > Ca2+ > Na+ > K+ whereas the abundance of anions are in the order SO4 2- > Cl- > HCO3 > NO3 - > F-. The result obtained in this investigation inferred that the cations in water i.e. sodium and iron are within the permissible limits but magnesium and potassium have exceeded the permissible limit. Whereas anions such as nitrate and fluoride are within the permissible range but chloride and sulphate have exceeded the permissible limits. The concentration of cation, magnesium (Mg) and potassium (K) in the lake water has exceeded the desirable range (30, 10 mg/L, respectively). This may be due to weathering and transported from rocks and particularly from sulphate deposits such as gypsum and anhydride and subsequently ends up in water. The concentration of anion, Sulphate (SO4) and chloride are above the desirable limit. The major source of bicarbonate are the carbonate rocks containing calcite (CaCO3) and dolomite (CaMg (CO3)2), Calcium (Ca) and Magnesium

  5. Factors controlling groundwater quality in the Yeonjegu District of Busan City, Korea, using the hydrogeochemical processes and fuzzy GIS.

    Science.gov (United States)

    Venkatramanan, Senapathi; Chung, Sang Yong; Selvam, Sekar; Lee, Seung Yeop; Elzain, Hussam Eldin

    2017-10-01

    The hydrogeochemical processes and fuzzy GIS techniques were used to evaluate the groundwater quality in the Yeonjegu district of Busan Metropolitan City, Korea. The highest concentrations of major ions were mainly related to the local geology. The seawater intrusion into the river water and municipal contaminants were secondary contamination sources of groundwater in the study area. Factor analysis represented the contamination sources of the mineral dissolution of the host rocks and domestic influences. The Gibbs plot exhibited that the major ions were derived from the rock weathering condition. Piper's trilinear diagram showed that the groundwater quality was classified into five types of CaHCO3, NaHCO3, NaCl, CaCl2, and CaSO4 types in that order. The ionic relationship and the saturation mineral index of the ions indicated that the evaporation, dissolution, and precipitation processes controlled the groundwater chemistry. The fuzzy GIS map showed that highly contaminated groundwater occurred in the northeastern and the central parts and that the groundwater of medium quality appeared in most parts of the study area. It suggested that the groundwater quality of the study area was influenced by local geology, seawater intrusion, and municipal contaminants. This research clearly demonstrated that the geochemical analyses and fuzzy GIS method were very useful to identify the contaminant sources and the location of good groundwater quality.

  6. 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

  7. Hydrogeochemical evaluation of the Simpevarp area, model version 1.1

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-02-01

    Siting studies for SKB's programme of deep geological disposal of nuclear fuel waste currently involves the investigation of two locations, Simpevarp and Forsmark, on the eastern coast of Sweden to determine their geological, hydrogeochemical and hydrogeological characteristics. Present work completed has resulted in model version 1.1 which represents the first evaluation of the available Simpevarp groundwater analytical data collected up to July 1st, 2003 (i.e. the first 'data freeze' of the site). The HAG (Hydrochemical Analytical Group) group had access to a total of 535 water samples collected 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 fracture groundwater samples with sufficient analytical data reflected depths down to 250 m. Furthermore, most of the waters sampled (79%) 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 Simpevarp are a result of many factors such as: a) the flat topography and proximity to the Baltic Sea, b) 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 composition caused by microbial processes or water/rock interactions. The sampled groundwaters reflect to various degrees of modern or ancient water/rock interactions and mixing processes. Higher topography to the west of Simpevarp has resulted in hydraulic gradients which have partially flushed out old water types. Except for sea waters, most surface waters and some groundwaters from percussion boreholes are fresh, non-saline waters according to the classification used for Aespoe groundwaters. The rest

  8. Hydrogeochemical impact of CO{sub 2} leakage from geological sequestration on shallow potable aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Cahill, A.G.

    2013-09-15

    Over the past 10 years scientists have worked in earnest to understand the potential effects of leakage in order that an informed decision on CCGS implementation can be made. This research can be broadly described as aiming to answer two key questions; how deleterious is leakage of CCGS to groundwater resources? and can it be detected geochemically? Some common hydrochemical development is apparent from the literature however many aspects of hydrogeological and hydrogeochemical impact of leakage into shallow aquifers used in water supply remain unclear. In this Ph.D. study an integrated approach was employed in order to answer the two key questions regarding leakage of CO{sub 2} into shallow aquifers. Consequently a combination of laboratory and field investigations were conducted supported by numerical geochemical modeling in order to identify, constrain and quantify processes controlling groundwater chemistry evolution. The output is 4 journal articles and 3 technical reports. In paper I and technical report I simple batch reactors were employed coupled to comprehensive sediment characterization to determine the likely effects of CO{sub 2} on water chemistry in a range of shallow aquifers. Results showed aquifers can be broadly divided into three types; carbonate dominated, silicate dominated and mixed. Each aquifer type showed distinct water chemistry evolution thus inherent risks vary. These studies also highlighted the complexity of risk assessment and detection caused by the range of formation types potentially overlying storage reservoirs. Investigations described in Papers II, III and technical report II increase applicability to real leakage by observing in situ effects including groundwater flow. A silicate dominated shallow aquifer in Vroegum, western Denmark forms the focus of study upon which a series of investigations were conducted. The main field study involved injection of 1600 kg of gas phase CO{sub 2} into the shallow Vroegum aquifer over 72 days

  9. 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

  10. The Survey of hydro-geochemical and health related of water quality in Ramian city, Golestan province

    Directory of Open Access Journals (Sweden)

    fahimeh Khanduzi

    2015-12-01

    Full Text Available Background and Purpose: Investigation of water quality is an important step for the suitable use of water resources in order to drinking and irrigation. Water quality affects agriculture programming.  Hence the need of the study of water quality is strongly considered in the water resources management. Material and Methods: In this study Hydro-geochemical quality of ground water resources in the Ramian city -Golestan province has been studied for drinking and agriculture purpose. For this purpose, 15 qualitative characteristics of the 13 wells of Golestan province in two dry and wet seasons in 2011-2012 were analyzed by Aua Chem and Aq-qa. Results: The results showed that the ground water in the study area is classified in hard and very hard water. The original cations and anions in water are Ca2+> Mg2+> Na+ and HCO3-> Cl-> SO42-. Based on hydro-chemical diagram the dominant of water type is classified as Ca-HCO3. Salinity index of water indicated that more samples in two seasons are in the middle class. According to Schuler and Wilcox groundwater quality index, they are moderate suitable for agricultural and drinking consumption and in for agricultural purpose and 77% cases are in C3-S1 category. Conclusion: The results show that too much salt is one of the most important problems of water supply in the Ramian city for irrigation. This reduced plant growth or even stops the growth of some plant. If water resources in this area do not manage, after shortly time the soil will be suffered and polluted.

  11. Investigation of hydrogeochemical properties of the Hüdai (Afyon ...

    Indian Academy of Sciences (India)

    Sandıklı-Hüdai geothermal field is one of the geothermal systems in Afyon and environ, located approximately 40 km southwest of Afyon. The study area consists of volcanic, sedimentary and metamorphic rocks. Kestel greenschist formation of Paleozoic age forms the basement rock in the area while quartzite which is a ...

  12. Investigation of hydrogeochemical properties of the Hüdai (Afyon ...

    Indian Academy of Sciences (India)

    Sandıklı-Hüdai geothermal field is one of the geothermal systems in Afyon and environ, located approx- imately 40 km southwest of Afyon. The study area consists of volcanic, sedimentary and metamorphic rocks. Kestel greenschist formation of Paleozoic age forms the basement rock in the area while quartzite which is a ...

  13. Investigation of Hydro-Geochemical Characteristics of Groundwater ...

    African Journals Online (AJOL)

    The average temperature of the groundwater samples is 29 oC, The water is slightly acidic with pH values between 4.28 – 7.72. Elevated Electrical Conductivity (EC) values in some coastal wells suggest possible pollution by seawater. The study also reveals saltwater contamination in the area as Chloride contents in some ...

  14. Hydrogeochemical appraisal of fluoride in groundwater of Langtang ...

    African Journals Online (AJOL)

    Polished thin sections for rocks were prepared and studied. Geochemical results from analysis of the samples (rock and water) show that four major rock units make up the geology of the area; coarse porphyritic biotite granite, migmatite, rhyolite and riebeckite granites, the minor ones are pegmatite, trachyte, aplite and fine ...

  15. Uraniam hydrogeochemical and stream sediment reconnaissance of the Wiseman NTMS Quadrangle, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    1981-09-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Wiseman NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form through the Grand Junction Office Information System at Oak Ridge National Laboratory. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field observations have not been included in this volume. These data are, however, available on the magnetic tape. Appendix A describes the sample media and summarizes the analytical results for each medium. The data were subdivided by one of the Los Alamos National Laboratory (LANL) sorting programs of Zinkl and others (198a) into stream sediment samples.

  16. Uranium hydrogeochemical and stream sediment reconnaissance of the Philip Smith Mountains NTMS quadrangle, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    1981-09-01

    Results of a hydrogeochemical and stream sediment reconnaissance of the Philip Smith Mountains NTMS quadrangle, Alaska are presented. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. In this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume. These data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data were subsetted by one of the Los Alamos National Laboratory (LANL) sorting programs into groups of stream sediment and lake sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1000000 scale maps of pertinent elements have been included in this report.

  17. Uranium hydrogeochemical and stream sediment reconnaissance of the Mt. Hayes NTMS quadrangle, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    1981-05-01

    Results of a hydrogeochemical and stream sediment reconnaissance of the Mt. Hayes quadrangle, Alaska, are presented. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. In this data release are location data, field analyses, and Laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume. These data are, however, available on the magnetic tape. Appendices A to D describe the sample media and summarize the analytical results for each medium. The data were subsetted by one of the Los Alamos National Laboratory (LANL) sorting programs into groups of stream sediment, lake sediment, stream water, lake water, and ground water samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1000000 scale maps of pertinent elements have been included in this report.

  18. Uranium hydrogeochemical and stream sediment reconnaissance of the Yakutat NTMS quadrangle, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    1981-09-01

    Results of a hydrogeochemical and stream sediment reconnaissance of the Yakutat NTMS quadrangle, Alaska are presented. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. In this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume. These data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data were subsetted by one of the Los Alamos National Laboratory (LANL) sorting programs into groups of stream sediment and lake sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1000000 scale maps of pertinent elements have been included in this report.

  19. Groundwater Recharge and Hydrogeochemical Evolution in Leizhou Peninsula, China

    Directory of Open Access Journals (Sweden)

    Yintao Lu

    2015-01-01

    Full Text Available An analysis of the stable isotopes and the major ions in the surface water and groundwater in the Leizhou Peninsula was performed to identify the sources and recharge mechanisms of the groundwater. In this study, 70 water samples were collected from rivers, a lake, and pumping wells. The surface water was considered to have a lower salinity than the groundwater in the region of study. The regression equations for δD and δ18O for the surface water and the groundwater are similar to those for precipitation, indicating meteoric origins. The δD and δ18O levels in the groundwater ranged from −60‰; to −25‰; and −8.6‰; to −2.5‰, respectively, and were lower than the stable isotope levels from the winter and spring precipitation. The groundwater in the southern area was classified as the Ca2+-Mg2+-HCO3--type, whereas the groundwater in the northern area included three types (Na+-Cl−-type, Ca2+-Mg2+-HCO3--type, and Ca2+-Mg2+-Cl−-type, indicating rapid and frequent water-rock exchange in the region. A reasonable conclusion is that the groundwater chemistry is dominated by rock weathering and rainwater of local origin, which are influenced by seawater carried by the Asian monsoon.

  20. Hydrogeochemical characteristics and sources of salinity of the springs near Wenquanzhen in the eastern Sichuan Basin, China

    Science.gov (United States)

    Guo, Juan; Zhou, Xun; Wang, Lidong; Zhang, Yuqi; Shen, Xiaowei; Zhou, Haiyan; Ye, Shen; Fang, Bin

    2017-12-01

    Natural springs have the potential to provide important information on hydrogeochemical processes within aquifers. This study used traditional and classic technical methods and procedures to determine the characteristics and evolution of springs to gain further knowledge on the differences between hot saline springs and cold fresh springs. In a short river segment near Wenquanzhen in the eastern Sichuan Basin, southwest China, several natural springs coexist with total dissolved solids (TDS) ranging from less than 1 to 15 g/L and temperatures from 15 to 40 °C. The springs emanate from the outcropping Lower and Middle Triassic carbonates in the river valley cutting the core of an anticline. The cold springs are of Cl·HCO3-Na·Ca and Cl·SO4-Na types, and the hot saline springs are mainly of Cl-Na type. The chemistry of the springs has undergone some changes with time. The stable hydrogen and oxygen isotopes indicate that the spring waters are of a meteoric origin. The salinity of the springs originates from dissolution of minerals, including halite, gypsum, calcite and dolomite. The evolution of the springs involves the following mechanisms: the groundwater receives recharge from infiltration of precipitation, then undergoes deep circulation in the core of the anticline (incongruent dissolution of the salt-bearing strata occurs), and emerges in the river valley in the form of hot springs with high TDS. Groundwater also undergoes shallow circulation in the northern and southern flanks of the anticline and appears in the river valley in the form of cold springs with low TDS.

  1. The assessment of processes controlling the spatial distribution of hydrogeochemical groundwater types in Mali using multivariate statistics

    Science.gov (United States)

    Keita, Souleymane; Zhonghua, Tang

    2017-10-01

    Sustainable management of groundwater resources is a major issue for developing countries, especially in Mali. The multiple uses of groundwater led countries to promote sound management policies for sustainable use of the groundwater resources. For this reason, each country needs data enabling it to monitor and predict the changes of the resources. Also given the importance of groundwater quality changes often marked by the recurrence of droughts; the potential impacts of regional and geological setting of groundwater resources requires careful study. Unfortunately, recent decades have seen a considerable reduction of national capacities to ensure the hydrogeological monitoring and production of qualit data for decision making. The purpose of this work is to use the groundwater data and translate into useful information that can improve water resources management capacity in Mali. In this paper, we used groundwater analytical data from accredited, laboratories in Mali to carry out a national scale assessment of the groundwater types and their distribution. We, adapted multivariate statistical methods to classify 2035 groundwater samples into seven main groundwater types and built a national scale map from the results. We used a two-level K-mean clustering technique to examine the hydro-geochemical records as percentages of the total concentrations of major ions, namely sodium (Na), magnesium (Mg), calcium (Ca), chloride (Cl), bicarbonate (HCO3), and sulphate (SO4). The first step of clustering formed 20 groups, and these groups were then re-clustered to produce the final seven groundwater types. The results were verified and confirmed using Principal Component Analysis (PCA) and RockWare (Aq.QA) software. We found that HCO3 was the most dominant anion throughout the country and that Cl and SO4 were only important in some local zones. The dominant cations were Na and Mg. Also, major ion ratios changed with geographical location and geological, and climatic

  2. Hydrogeochemical investigation of Küçük Menderes River coastal wetland, Selçuk-Izmir, Turkey

    Science.gov (United States)

    Somay, A. Melis; Gemici, Ünsal; Filiz, Sevki

    2008-07-01

    Küçük Menderes River forms a rich coastal wetland inside in the Selçuk plain. Three saline/brackish lakes, one swamp and Küçük Menderes River are these wetlands’ components. Alkaline-slightly alkaline type lakes are recharged from precipitation and karstic springs that discharge from marble-schist and marble-alluvium contacts in the northern and southern parts of the study area. Water types of the wetland are Na-Cl and Na-Ca-Mg-HCO3-Cl in both rainy and dry seasons. Both seawater intrusion and evaporation, as being the sources of the ions, justify the presence of Na-Cl, Na-SO4 and Cl-SO4, in the wetland water. Environmental isotopes were used to identify the relationship between wetland and groundwater in the Selçuk plain. The δ18O and δD composition of wetland area samples have changed between -6.42 to -4.56‰, and -36.40 to -23.80‰, respectively. The lakes and rivers are plotted on the mixing line by slope of 5.2 and these data indicate that wetland is affected from seawater intrusion. The recharge area that was sampled in order to compare the wetland has Ca-HCO3 water type with a neutral-slightly alkaline pH values and the main hydrogeochemical process is weathering the different types of silicates. Iron, manganese and selenium are the dominant minor ions due to the high biological activities and organic matters in the lakes. There are two contamination risks for this wetland: (1) waste disposal site and (2) water treatment plant where the purified waters are released into the river. EC, Al, As, Cd, Cu, Fe and Zn values exceed those of aquatic life standards. In the near future these sites will pose a danger for wetland wild life and surrounding irrigation water suppliers.

  3. Uranium hydrogeochemical and stream sediment reconnaissance of the Survey Pass NTMS quadrangle, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Shettel, D.L. Jr.; Langfeldt, S.L.; Youngquist, C.A.; D' Andrea, R.F. Jr.; Zinkl, R.J. (comps.)

    1981-09-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Survey Pass NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form through the Grand Junction Office Information System at Oak Ridge National Laboratory. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume. These data are, however, available on the magnetic tape. Appendix A describes the sample media and summarizes the analytical results for each medium. The data were subdivided by one of the Los Alamos National Laboratory (LANL) sorting programs of Zinkl and others (1981a) into stream sediment samples. For the group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1000000 scale maps of pertinent elements have been included in this report. In addition, maps showing results of multivariate statistical analyses have been included. Further information about the HSSR program in general, or about the LANL portion of the program in particular, can be obtained in quarterly or semiannual program progress reports on open-file at DOE's Technical Library in Grand Junction. Information about the field and analytical procedures used by LANL during sample collection and analysis may be found in any HSSR data release prepared by the LANL and will not be included in this report.

  4. HYDROGEOCHEM: A coupled model of HYDROlogic transport and GEOCHEMical equilibria in reactive multicomponent systems

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, G.T.; Tripathi, V.S.

    1990-11-01

    This report presents the development of a hydrogeochemical transport model for multicomponent systems. The model is designed for applications to proper hydrological setting, accommodation of complete suite of geochemical equilibrium processes, easy extension to deal with chemical kinetics, and least constraints of computer resources. The hydrological environment to which the model can be applied is the heterogeneous, anisotropic, saturated-unsaturated subsurface media under either transient or steady state flow conditions. The geochemical equilibrium processes included in the model are aqueous complexation, adsorption-desorption, ion exchange, precipitation-dissolution, redox, and acid-base reactions. To achieve the inclusion of the full complement of these geochemical processes, total analytical concentrations of all chemical components are chosen as the primary dependent variables in the hydrological transport equations. Attendant benefits of this choice are to make the extension of the model to deal with kinetics of adsorption-desorption, ion exchange, precipitation-dissolution, and redox relatively easy. To make the negative concentrations during the iteration between the hydrological transport and geochemical equilibrium least likely, an implicit form of transport equations are proposed. To alleviate severe constraints of computer resources in terms of central processing unit (CPU) time and CPU memory, various optional numerical schemes are incorporated in the model. The model consists of a hydrological transport module and geochemical equilibrium module. Both modules were thoroughly tested in code consistency and were found to yield plausible results. The model is verified with ten examples. 79 refs., 21 figs., 17 tabs.

  5. Hydrogeochemical processes in the Plio-Quaternary Remila aquifer (Khenchela, Algeria)

    Science.gov (United States)

    Aouidane, Laiche; Belhamra, Mohamed

    2017-06-01

    The Remila Plain is a synclinal structure in northeast Algeria, situated within a semi-arid climate zone and composed of Mio-Pliocene-Quaternary deposits. Within the syncline, the Plio-Quaternary aquifer is the main source of drinking water for cattle and for agricultural irrigation water. This work aims to investigate the origin of groundwater mineralization and to identify the primary hydrogeochemical processes controlling groundwater evolution in the Remila aquifer. A total of 86 water samples from boreholes were analyzed for major, minor and stable isotopes (18O, 2H) over three seasons: first during low water levels in 2013, second during high water levels in 2014 and third for stable isotopes during low water levels in 2015. The analysis showed that the aquifer is controlled by five principal geochemical processes: (I) the dissolution of evaporite rocks, (II) cation exchange and reverse exchange reactions, (III) congruent dissolution of carbonates (calcite, dolomite) coupled with the dissolution of gypsum and calcite precipitation, (IV) sulfate reduction under anaerobic conditions, and (V) saltwater intrusion in the northeastern Sabkha plains. The 18O and deuterium concentrations in groundwater are very low, indicating that the aquifer is recharged by evaporated rainfall originating from the north slope of the Aurès Mountains which confirms that the aquifer is recharged in the southern part of the plain.

  6. Hydrogeochemical investigations in a drained lake area: the case of Xynias basin (Central Greece).

    Science.gov (United States)

    Charizopoulos, Nikos; Zagana, Eleni; Stamatis, Georgios

    2016-08-01

    In Xynias drained Lake Basin's area, central Greece, a hydrogeochemical research took place including groundwater sampling from 30 sampling sites, chemical analysis, and statistical analysis. Groundwaters present Ca-Mg-HCO3 as the dominant hydrochemical type, while their majority is mixed waters with non-dominant ion. They are classified as moderately hard to hard and are characterized by oxidizing conditions. They are undersaturated with respect to gypsum, anhydrite, fluorite, siderite, and magnesite and oversaturated in respect to calcite, aragonite, and dolomite. Nitrate concentration ranges from 4.4 to 107.4 mg/L, meanwhile 13.3 % of the samples exceed the European Community (E.C.) drinking water permissible limit. The trace elements Fe, Ni, Cr, and Cd present values of 30, 80, 57, and 50 %, respectively, above the maximum permissible limit set by E.C. Accordingly, the majority of the groundwaters are considered unsuitable for drinking water needs. Sodium adsorption ratio values (0.04-3.98) and the electrical conductivity (227-1200 μS/cm) classify groundwaters as suitable for irrigation uses, presenting low risk and medium soil alkalization risk. Factor analysis shows that geogenic processes associated with the former lacustrine environment and anthropogenic influences with the use of fertilizers are the major factors that characterized the chemical composition of the groundwaters.

  7. Hydrogeochemical alteration of groundwater due to a CO2 injection test into a shallow aquifer in Northeast Germany

    Science.gov (United States)

    Dethlefsen, Frank; Peter, Anita; Hornbruch, Götz; Lamert, Hendrik; Garbe-Schönberg, Dieter; Beyer, Matthias; Dietrich, Peter; Dahmke, Andreas

    2014-05-01

    The accidental release of CO2 into potable aquifers, for instance as a consequence of a leakage out of a CO2 store site, can endanger drinking water resources due to the induced geochemical processes. A 10-day CO2 injection experiment into a shallow aquifer was carried out in Wittstock (Northeast Germany) in order to investigate the geochemical impact of a CO2 influx into such an aquifer and to test different monitoring methods. Information regarding the site investigation, the injection procedure monitoring setup, and first geochemical monitoring results are described in [1]. Apart from the utilization of the test results to evaluate monitoring approaches [2], further findings are presented on the evaluation of the geophysical monitoring [3], and the monitoring of stable carbon isotopes [4]. This part of the study focuses of the hydrogeochemical alteration of groundwater due to the CO2 injection test. As a consequence of the CO2 injection, major cations were released, i.e. concentrations increased, whereas major anion concentrations - beside bicarbonate - decreased, probably due to increased anion sorption capacity at variably charged exchange sites of minerals. Trace element concentrations increased as well significantly, whereas the relative concentration increase was far larger than the relative concentration increase of major cations. Furthermore, geochemical reactions show significant spatial heterogeneity, i.e. some elements such as Cr, Cu, Pb either increased in concentration or remained at stable concentrations with increasing TIC at different wells. Statistical analyses of regression coefficients confirm the different spatial reaction patterns at different wells. Concentration time series at single wells give evidence, that the trace element release is pH dependent, i.e. trace elements such as Zn, Ni, Co are released at pH of around 6.2-6.6, whereas other trace elements like As, Cd, Cu are released at pH of 5.6-6.4. [1] Peter, A., et al., Investigation of

  8. Hydrogeochemical and stable isotopic investigations on CO2-rich mineral waters from Harghita Mts. (Eastern Carpathians, Romania)

    Science.gov (United States)

    Kis, Boglárka-Mercedesz; Baciu, Călin; Kármán, Krisztina; Kékedy-Nagy, Ladislau; Francesco, Italiano

    2013-04-01

    There is a worldwide interest on geothermal, mineral and groundwater as a resource for energy, drinking water supply and therapeutic needs. The increasing trend in replacing tap water with commercial bottled mineral water for drinking purposes has become an economic, hydrogeologic and medical concern in the last decades. Several investigations have been carried out worldwide on different topics related to geothermal and mineral waters, dealing with mineral water quality assessment, origin of geothermal and mineral waters, geochemical processes that influence water chemistry and water-rock interaction In Romania, the Călimani-Gurghiu-Harghita Neogene to Quaternary volcanic chain (Eastern Carpathians) is one of the most important areas from the point of view of CO2-rich mineral waters. These mineral water springs occur within other post-volcanic phenomena like dry CO2 emissions, moffettes, bubbling pools, H2S gas emissions etc. Mineral waters from this area are used for bottling, local spas and drinking purposes for local people. The number of springs, around 2000 according to literature data, shows that there is still a significant unexploited potential for good quality drinking water in this area. Within the youngest segment of the volcanic chain, the Harghita Mts., its volcaniclastic aprons and its boundary with the Transylvanian Basin, we have carried out an investigation on 23 CO2-rich mineral water springs from a hydrogeochemical and stable isotopic point of view. The mineral waters are Ca-Mg-HCO3 to Na-Cl type. Sometimes mixing between the two types can be observed. We have detected a great influence of water-rock interaction on the stable isotopic composition of the mineral waters, shown by isotopic shifts to the heavier oxygen isotope, mixing processes between shallow and deeper aquifers and local thermal anomalies. Acknowledgements: The present work was financially supported by the Romanian National Research Council, Project PN-II-ID-PCE-2011-3-0537 and by

  9. Geoelectrical Resistivity and Hydrogeochemical Contrast between the Area that Has Been Applied with Fertilization for Long Duration and Non-Fertilization

    Directory of Open Access Journals (Sweden)

    Nur Islami

    2010-11-01

    Full Text Available Integrated geoelectrical resistivity, hydrogeochemical and soil properties analysis methods were used to study the area that has been applied with fertilization for long duration and non-Fertilization in Machang, North Kelantan. The Machang plain is covered with Quaternary fluvial sediments overlying granite bedrock. The drainage system is dendritic with the main river flowing into the South China Sea. In this study, the area was divided into two sites. Site-1 is the non-fertilized site, and Site-2 is the regularly-fertilized site. At shallow depth from the surface to depths of 75 cm a lower average geoelectrical resistivity values were obtained from the regularly fertilized site which has not been fertilized for the last ten months prior to the survey. The average resistivity values were around 0.366 times less in unfertilized sites. Residual nitrate and chloride were still present at the regularly chemically fertilized sites. At sites where no chemical fertilizer was added, the nitrate and chloride concentration were also found. These are due to the faces excretion of from the farm animals. The presence of nitrate and chloride content in pore water reduced the resistivity values. Thus despite low moisture content, the resistivity values to remain low. Normally, resistivity values are inversely proportional to moisture content for area with similar soil condition

  10. Preliminary assessment of the geothermal potential of Rosario de la Frontera area (Salta, NW Argentina): Insight from hydro-geological, hydro-geochemical and structural investigations

    Science.gov (United States)

    Invernizzi, C.; Pierantoni, P. P.; Chiodi, A.; Maffucci, R.; Corrado, S.; Baez, W.; Tassi, F.; Giordano, G.; Viramonte, J.

    2014-10-01

    This work is part of a project aimed to the development and application of hydrogeological, hydrogeochemical and geological methodologies for the study of the geothermal system of Rosario de La Frontera (NW Argentina). The surface thermal manifestations of this area, whose temperatures range from 22.6 to 92.6 °C, are mainly located in the northern sector of Sierra de la Candelaria anticline. This regional structure crops out between the provinces of Salta and Tucuman (NW Argentina), at the foothills of the central Andean retro-wedge. The present investigation focuses on hydrogeological and structural data, and isotopic compositions (18O, D and 3H) of thermal springs. Preliminary results allowed to define: i) the meteoric origin of spring water and their long (more than 50 years) residence time at depth, ii) a positive water balance, ranging between 2 and 4 millions of m3/yr, and iii) a conservative geothermal reservoir volume of about 39 km3, iv) a geothermal potential with Er = 5.6*1018 J and Ef = 0.8*1018 J.

  11. Application of multivariate statistical technique for hydrogeochemical assessment of groundwater within the Lower Pra Basin, Ghana

    Science.gov (United States)

    Tay, C. K.; Hayford, E. K.; Hodgson, I. O. A.

    2017-06-01

    Multivariate statistical technique and hydrogeochemical approach were employed for groundwater assessment within the Lower Pra Basin. The main objective was to delineate the main processes that are responsible for the water chemistry and pollution of groundwater within the basin. Fifty-four (54) (No) boreholes were sampled in January 2012 for quality assessment. PCA using Varimax with Kaiser Normalization method of extraction for both rotated space and component matrix have been applied to the data. Results show that Spearman's correlation matrix of major ions revealed expected process-based relationships derived mainly from the geochemical processes, such as ion-exchange and silicate/aluminosilicate weathering within the aquifer. Three main principal components influence the water chemistry and pollution of groundwater within the basin. The three principal components have accounted for approximately 79% of the total variance in the hydrochemical data. Component 1 delineates the main natural processes (water-soil-rock interactions) through which groundwater within the basin acquires its chemical characteristics, Component 2 delineates the incongruent dissolution of silicate/aluminosilicates, while Component 3 delineates the prevalence of pollution principally from agricultural input as well as trace metal mobilization in groundwater within the basin. The loadings and score plots of the first two PCs show grouping pattern which indicates the strength of the mutual relation among the hydrochemical variables. In terms of proper management and development of groundwater within the basin, communities, where intense agriculture is taking place, should be monitored and protected from agricultural activities. especially where inorganic fertilizers are used by creating buffer zones. Monitoring of the water quality especially the water pH is recommended to ensure the acid neutralizing potential of groundwater within the basin thereby, curtailing further trace metal

  12. The effects of physical and geochemical heterogeneities on hydro-geochemical transport and effective reaction rates

    Science.gov (United States)

    Atchley, Adam L.; Navarre-Sitchler, Alexis K.; Maxwell, Reed M.

    2014-09-01

    The role of coupled physical and geochemical heterogeneities in hydro-geochemical transport is investigated by simulating three-dimensional transport in a heterogeneous system with kinetic mineral reactions. Ensembles of 100 physically heterogeneous realizations were simulated for three geochemical conditions: 1) spatially homogeneous reactive mineral surface area, 2) reactive surface area positively correlated to hydraulic heterogeneity, and 3) reactive surface area negatively correlated to hydraulic heterogeneity. Groundwater chemistry and the corresponding effective reaction rates were calculated at three transverse planes to quantify differences in plume evolution due to heterogeneity in mineral reaction rates and solute residence time (τ). The model is based on a hypothetical CO2 intrusion into groundwater from a carbon capture utilization and storage (CCUS) operation where CO2 dissolution and formation of carbonic acid created geochemical dis-equilibrium between fluids and the mineral galena that resulted in increased aqueous lead (Pb2 +) concentrations. Calcite dissolution buffered the pH change and created conditions of galena oversaturation, which then reduced lead concentrations along the flow path. Near the leak kinetic geochemical reactions control the release of solutes into the fluid, but further along the flow path mineral solubility controls solute concentrations. Simulation results demonstrate the impact of heterogeneous distribution of geochemical reactive surface area in coordination with physical heterogeneity on the effective reaction rate (Krxn,eff) and Pb2 + concentrations within the plume. Dissimilarities between ensemble Pb2 + concentration and Krxn,eff are attributed to how geochemical heterogeneity affects the time (τeq) and therefore advection distance (Leq) required for the system to re-establish geochemical equilibrium. Only after geochemical equilibrium is re-established, Krxn,eff and Pb2 + concentrations are the same for all three

  13. Uranium hydrogeochemical and stream-sediment reconnaissance of the Big Delta NTMS quadrangle, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L. C.; D& #x27; Andrea, Jr., R. F.; Zinkl, R. J.; Shettel, Jr., D. L.; Langfeldt, S. L. [comps.

    1982-02-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Big Delta NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into groups of stream-sediment and lake-sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report.

  14. Uranium hydrogeochemical and stream-sediment reconnaissance of the Mt. Michelson NTMS quadrangle, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Zinkl, R.J.; Shettel, D.L. Jr.; Langfeldt, S.L.; Hardy, L.C.; D' Andrea, R.F. Jr. (comps.)

    1982-04-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Mt. Michelson NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into groups of stream-sediment and lake-sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report.

  15. The effects of physical and geochemical heterogeneities on hydro-geochemical transport and effective reaction rates.

    Science.gov (United States)

    Atchley, Adam L; Navarre-Sitchler, Alexis K; Maxwell, Reed M

    2014-09-01

    The role of coupled physical and geochemical heterogeneities in hydro-geochemical transport is investigated by simulating three-dimensional transport in a heterogeneous system with kinetic mineral reactions. Ensembles of 100 physically heterogeneous realizations were simulated for three geochemical conditions: 1) spatially homogeneous reactive mineral surface area, 2) reactive surface area positively correlated to hydraulic heterogeneity, and 3) reactive surface area negatively correlated to hydraulic heterogeneity. Groundwater chemistry and the corresponding effective reaction rates were calculated at three transverse planes to quantify differences in plume evolution due to heterogeneity in mineral reaction rates and solute residence time (τ). The model is based on a hypothetical CO2 intrusion into groundwater from a carbon capture utilization and storage (CCUS) operation where CO2 dissolution and formation of carbonic acid created geochemical dis-equilibrium between fluids and the mineral galena that resulted in increased aqueous lead (Pb(2+)) concentrations. Calcite dissolution buffered the pH change and created conditions of galena oversaturation, which then reduced lead concentrations along the flow path. Near the leak kinetic geochemical reactions control the release of solutes into the fluid, but further along the flow path mineral solubility controls solute concentrations. Simulation results demonstrate the impact of heterogeneous distribution of geochemical reactive surface area in coordination with physical heterogeneity on the effective reaction rate (Krxn,eff) and Pb(2+) concentrations within the plume. Dissimilarities between ensemble Pb(2+) concentration and Krxn,eff are attributed to how geochemical heterogeneity affects the time (τeq) and therefore advection distance (Leq) required for the system to re-establish geochemical equilibrium. Only after geochemical equilibrium is re-established, Krxn,eff and Pb(2+) concentrations are the same for all

  16. Semi-supervised Machine Learning for Analysis of Hydrogeochemical Data and Models

    Science.gov (United States)

    Vesselinov, Velimir; O'Malley, Daniel; Alexandrov, Boian; Moore, Bryan

    2017-04-01

    Data- and model-based analyses such as uncertainty quantification, sensitivity analysis, and decision support using complex physics models with numerous model parameters and typically require a huge number of model evaluations (on order of 10^6). Furthermore, model simulations of complex physics may require substantial computational time. For example, accounting for simultaneously occurring physical processes such as fluid flow and biogeochemical reactions in heterogeneous porous medium may require several hours of wall-clock computational time. To address these issues, we have developed a novel methodology for semi-supervised machine learning based on Non-negative Matrix Factorization (NMF) coupled with customized k-means clustering. The algorithm allows for automated, robust Blind Source Separation (BSS) of groundwater types (contamination sources) based on model-free analyses of observed hydrogeochemical data. We have also developed reduced order modeling tools, which coupling support vector regression (SVR), genetic algorithms (GA) and artificial and convolutional neural network (ANN/CNN). SVR is applied to predict the model behavior within prior uncertainty ranges associated with the model parameters. ANN and CNN procedures are applied to upscale heterogeneity of the porous medium. In the upscaling process, fine-scale high-resolution models of heterogeneity are applied to inform coarse-resolution models which have improved computational efficiency while capturing the impact of fine-scale effects at the course scale of interest. These techniques are tested independently on a series of synthetic problems. We also present a decision analysis related to contaminant remediation where the developed reduced order models are applied to reproduce groundwater flow and contaminant transport in a synthetic heterogeneous aquifer. The tools are coded in Julia and are a part of the MADS high-performance computational framework (https://github.com/madsjulia/Mads.jl).

  17. Hydrogeochemical modelling of seawater injection into offshore oil fields; Modellierung hydrogeochemischer Prozesse bei der Injektion von Meerwasser in Offshore-Oellagerstaetten

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Yunjiao; Berk, Wolfgang van [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Abt. Hydrogeologie; Schulz, Hans-Martin [Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum (GFZ), Potsdam (Germany). Sek. 4.3 - Organische Geochemie

    2013-01-15

    Sea water is injected into offshore oilfields and coastal-near onshore fields to maintain pressure for secondary recovery. Due to compositional differences of sea water and formation water, hydrogeochemical processes are initiated. Such processes develop from the injection well along the migration path through the reservoir, and reach the production well. Ultimately, the mixing ratio of the two water types controls processes such as precipitation of minerals or dissolution of minerals from the reservoir rock. Here, we are introducing mass balance models based on chemical thermodynamics as a hydrogeochemical tool to qualitatively and quantitatively retrace such processes. It is the aim to demonstrate how mixing of sea and formation water controls type and amount of scaling and mineral dissolution, exemplarily in the UK Miller oilfield (North Sea). The presented approach and the results shall highlight the applicability of hydrogeochemical mass balance models in order to predict scale-forming processes. Finally, an outlook is presented about predictive hydrogeochemical 1D- and 3D-transport models in development. (orig.)

  18. Hydrogeochemical characterization of fluoride rich groundwater of Wailpalli watershed, Nalgonda District, Andhra Pradesh, India.

    Science.gov (United States)

    Reddy, A G S; Reddy, D V; Rao, P N; Prasad, K Maruthy

    2010-12-01

    The groundwater of Nalgonda district is well known for its very high fluoride content for the past five decades. Many researchers have contributed their scientific knowledge to unravel causes for fluoride enrichment of groundwater. In the present paper, an attempt has been made to relate the high fluoride content in the groundwater to hydrogeochemical characterization of the water in a fracture hard rock terrain--the Wailpally watershed. Groundwater samples collected from all the major geomorphic units in pre- and post-monsoon seasons were analyzed for its major ion constituents such as Ca(2+), Mg(2+), Na(+), K(+), CO3-, HCO3-, Cl(-), SO4(-2), NO3-, and F(-). The groundwaters in the watershed have the average fluoride content of 2.79 mg/l in pre-monsoon and 2.83 mg/l in post-monsoon. Fluoride concentration in groundwater does not show perceptible change neither with time nor in space. The ionic dominance pattern is in the order of Na(+) > Ca(2+) > Mg(2+) > K(-) among cations and HCO3- Cl(-) > SO4(-2) NO3- F(-) among anions in pre-monsoon. In post-monsoon, Mg replaces Ca(2+) and NO3- takes the place of SO4(-2). The Modified Piper diagram reflect that the water belong to Ca(+2)-Mg(+2)-HCO3- to Na(+)-HCO3- facies. Negative chloralkali indices in both the seasons prove that ion exchange between Na(+) and K(+) in aquatic solution took place with Ca(+2) and Mg(+2) of host rock. The interpretation of plots for different major ions and molar ratios suggest that weathering of silicate rocks and water-rock interaction is responsible for major ion chemistry of groundwater in Wailpally watershed. Chemical characteristics and evolution of this fluoride-contaminated groundwater is akin to normal waters of other hard rock terrain; hence, it can be concluded that aquifer material play an important role in the contribution of fluoride in to the accompanying water. High fluoride content in groundwater can be attributed to the continuous water-rock interaction during the

  19. Aragonite-calcite precipitation in vertical fractures of the "Erzberg" siderite deposit (Austria): Hydrogeochemical and neotectonic implications

    Science.gov (United States)

    Boch, Ronny; Wang, Xianfeng; Kluge, Tobias; Kurz, Walter; Leis, Albrecht; Lin, Ke; Pluch, Hannes; Mittermayr, Florian; Dietzel, Martin

    2017-04-01

    The ore deposit "Erzberg" represents the worldwide largest FeCO3 occurrence and is amongst Austria's most prominent geological places due to its historic, economic and scientific value. The iron-ore (siderite/ankerite) bearing Devonian carbonates of the open pit mine locally host sequential aragonite-calcite precipitates infilling vertical fractures. These typically laminated carbonates are referred to as erzbergite in mineral collections. To study their formation conditions we recovered samples on-site, i.e. from the rare veins being cm to dm in horizontal and tenths of meters in vertical extension. Additionally, samples from our university collection and private collectors were investigated. Some of the fractures filled with aragonite/calcite further exhibit cataclastic sediments, damage zones and slickenside striations. Modern water samples were collected from fractures currently accessible to conduct hydrochemical analyses and modeling. Selected precipitates were analyzed applying microscopic techniques, XRD, electron microprobe elemental mapping, stable and clumped isotopes, and 238U-234U-230Th radiometric dating. Erzbergite veins show either uni- or bidirectional growth, i.e. on one or both fracture/fault planes toward complete infilling depending on vadose water flow. The laminated precipitates are dominated by aragonite relative to pristine as well as partially diagenetic (Mg)-calcite. Intercalated and recurrent brownish Fe-rich layers consisting of goethite, quartz, muscovite are probably of detrital origin. Stable C and O isotopes of the precipitates reveal pronounced spatiotemporal variations in which low δ18O values (-10.4 to -5.1 ‰ VPDB) reflect a meteoric origin and low temperatures of the erzbergite depositing solutions. Carbonate clumped isotope measurements verify formation temperatures ≤25 °C. High δ13C values (-0.7 to +6.8 ‰ VPDB) of the precipitates indicate an origin from dissolution of local ankerite and limestone, without a

  20. Hydro-geochemical characterization of Treated Domestic Waste Water for possible use in homestead irrigation and managed aquifer recharge in the coastal city of Khulna, Bangladesh

    Science.gov (United States)

    Hamid, T.; Ahmed, K. M.

    2016-12-01

    Bangladesh is among the most densely populated countries in the world. Rapid and unplanned urbanization in Bangladesh has resulted in heterogeneous land use pattern and larger demands for municipal water. To meet the ever-increasing demand of water for such population, the usage of treated domestic waste water (DWW) has become a viable option that can serve specific purposes, i.e. homestead irrigation, managed aquifer recharge (MAR) in major cities like Khulna, the largest city in the southwest coastal region. It is an attractive solution to minimize the deficit between the demand and supply of water in the study area where, in specific parts, city-dwellers suffer year round shortage of potable water due to high salinity in shallow depths. However, certain degree of treatment is mandatory for DWW in order to ensure the compliance of the output water with a set of standards and regulations for the DWW reuse. At present, the DWW is being treated through Constructed Wetlands but the treated water is not used and discharged into the sewer system. Wastewater that has been treated through a constructed wetland is a resource that can be used for productive uses in homestead garden irrigation, artificial aquifer recharge, and other non-potable uses. The study addresses the effectiveness of constructed wetlands in improving the quality of wastewater through on the hydro-geochemical characterization of both raw and treated DWW as well as baseline water quality analysis of surface and ground water in and around the treatment plant with consideration of seasonal variations. The study aims at sustainable development through conservation of water, satisfaction of demands, reliability of water supply, contribution to urban food supply, sustenance of livelihood and replenishment of the depleting aquifer by assessing the suitability of the treated DWW for various non-potable uses and also to provide guidelines for possible uses of treated DWW without adverse impact on environment

  1. Tracing environmental aetiological factors of chronic kidney diseases in the dry zone of Sri Lanka-A hydrogeochemical and isotope approach.

    Science.gov (United States)

    Wickramarathna, Sudeera; Balasooriya, Shyamalie; Diyabalanage, Saranga; Chandrajith, Rohana

    2017-12-01

    Chronic kidney disease of unknown aetiologies (CKDu) is increasingly recognized in tropical regions and is now considered a global health problem. A detailed hydrogeochemical investigation has been performed in three CKDu hotspots in Sri Lanka to assess the geo-environmental aetiological factors influencing this disease. A total of 71 ground- and 26 surface water samples were collected from Girandurukotte, Wilgamuwa and Nikawewa regions and analysed for major constituents and trace elements. The affected regions are dominated by Ca-Mg-HCO 3 facies groundwater that is mainly controlled by silicate weathering. Higher levels of fluoride associated with higher hardness is the main feature of groundwater from CKDu regions compared to non-CKDu regions. Results showed that 65% of the wells in the affected regions exceeded the fluoride concentration of 0.5mg/L. Environmental isotopes of groundwater in the CKDu regions are represented by the regression line of δ 2 H=5.42δ 18 O-3.59 (r 2 =0.916) with a clear isotopic differentiation between local precipitation and groundwater. None of the trace elements exceeded the recommended scales and in most cases levels are negligible in both surface and groundwater in study areas. Therefore, the involvement of trace elements such as Cd, As and Pb can be ignored as causative factors for CKDu. This study highlights the synergistic influence of fluoride and hardness that could enhance the disease, and thereby refute earlier theories that attribute trace elements as causative factors for CKDu. Higher hardness in drinking water also restricts sufficient water uptake, particularly by farmers and which affects the physiological, biochemical and nutritional requirements. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. Hydro-geochemical modeling of the spatial and the temporal geochemical variations of the granitic Strengbach catchment springs (Vosges massif, France)

    Science.gov (United States)

    Ackerer, Julien; Chabaux, François; Lucas, Yann; Pierret, Marie Claire; Viville, Daniel; Fritz, Bertrand; Clement, Alain; Beaulieu, Emilie; Negrel, Philippe

    2017-04-01

    Regular analysis of the major element concentrations in waters from springs emerging on the Strengbach catchment is made for more than 20 years (OHGE, Observatoire Hydro-Géochimique de l'Environnement). These data confirm the spatial variability of geochemical characteristics of the Strengbach springs linked, at least partly, to the lithological variability of the substratum (Pierret et al., 2014). The data also indicate that at the first order, the geochemical fluxes exported from each spring are mainly linked to the spring discharges, without significant variations of the relationships linking these two parameters between 1990 and 2010. There is also no observation of significant variations for the dissolved silica and for most of the cationic concentrations with time. Only a significant decrease of the Ca concentrations is observed for the Strengbach springs from 1990 to 2010. Numerical simulations, performed with the KIRMAT hydro-geochemical code, show that such a decrease can be considered as the response in the "bedrock" of the water-rock interactions to the variations of the soil solution chemical compositions recorded over the last 20 years, marked by a significant increase of pH and decrease of Ca concentrations. In particular, the modeling results show that the Ca concentration decrease is controlled by the couple apatite/clays, and that significant modifications of the apatite dissolution rate and clay compositions occurred between 1990 and 2010. This study shows that the temporal evolution of the Strengbach spring chemistry cannot be explained by the only variations of the clay mineral compositions, i.e. a modification of the chemical composition of the precipitated clays or a modification of the ionic exchange capacity of the clay minerals, but that it is definitely the interrelations between the apatite and the clay minerals that are involved.

  3. The groundwater quality of Aruba, Bonaire and Curaçao: a hydrogeochemical study

    NARCIS (Netherlands)

    Sambeek, M.H.G. van; Eggenkamp, H.G.M.; Vissers, M.J.M.

    2000-01-01

    Groundwater resources on the Caribbean Islands of Aruba, Bonaire and Curaçao are limited and of poor quality. The groundwater of the islands is brackish, due to both seawater mixing and the semi-arid climate of the islands.Two hundred and thirty water samples were collected to relate chemical

  4. Hydrogeochemical processes governing the origin, transport and fate of major and trace elements from mine wastes and mineralized rock to surface waters

    Science.gov (United States)

    Nordstrom, D. Kirk

    2011-01-01

    The formation of acid mine drainage from metals extraction or natural acid rock drainage and its mixing with surface waters is a complex process that depends on petrology and mineralogy, structural geology, geomorphology, surface-water hydrology, hydrogeology, climatology, microbiology, chemistry, and mining and mineral processing history. The concentrations of metals, metalloids, acidity, alkalinity, Cl-, F- and SO42- found in receiving streams, rivers, and lakes are affected by all of these factors and their interactions. Remediation of mine sites is an engineering concern but to design a remediation plan without understanding the hydrogeochemical processes of contaminant mobilization can lead to ineffective and excessively costly remediation. Furthermore, remediation needs a goal commensurate with natural background conditions rather than water-quality standards that might bear little relation to conditions of a highly mineralized terrain. This paper reviews hydrogeochemical generalizations, primarily from US Geological Survey research, that enhance our understanding of the origin, transport, and fate of contaminants released from mined and mineralized areas.

  5. Hydrogeochemical zonation and its implication for arsenic mobilization in deep groundwaters near alluvial fans in the Hetao Basin, Inner Mongolia

    Science.gov (United States)

    Jia, Yongfeng; Guo, Huaming; Jiang, Yuxiao; Wu, Yang; Zhou, Yinzhu

    2014-10-01

    High As groundwater has been found in shallow aquifers of the flat plain of the Hetao basin, but little is known about As concentration in deep groundwaters around piedmont areas, which are the major drinking water resources. One hundred and three groundwater samples from wells with depths >50 m and seven samples from one multi-level monitoring well (89 m in depth) were analyzed for chemical compositions and 18O and D isotopes to examine the geochemical processes controlling As mobilization. According to hydrogeological setting, chemical and isotopic characteristics of deep groundwater, three distinguished hydrogeochemical zones are delineated, including Recharge-Oxic Zone (Zone I), Groundwater Flow-Moderate Reducing Zone (Zone II), and Groundwater Flow-Reducing Zone (Zone III). Zone I is located in proximal fans in the recharge area with oxic conditions, where low As groundwater generally occurs. In Zone II, located in the intermediate between the fans and the flat plain with Fe-reduction predominated, groundwater As is moderate. Zone III lies in the flat plain with the occurrence of SO42- reduction, where high As groundwater is mostly found. This indicates that release of As to groundwater is primarily determined by reduction sequences. Arsenic is immobilized in O2 /NO3- reduction stage in Zone I and released in Fe-reducing conditions of Zone II, and displays a significant elevated concentration in SO4-reducing stage in Zone III. Dissolution of carbonate minerals occurs in Zone I, while Ca2+ and Mg2+ are expected to precipitate in Zone II and Zone III. In the multi-level monitoring well, both chemical and isotopic compositions are dependent of sampling depths, with the similar trend to the hydrogeochemical zonation along the flow path. The apparent increases in δD and δ18O values in Zone III reveal the possibility of high As shallow groundwater recharge to deep groundwater. It indicates that deep groundwaters in proximal fans have low As concentrations and are

  6. Hydrogeochemical characterization of a shallow groundwater system in the weathered basement aquifer of Ilesha area, southwestern Nigeria

    Directory of Open Access Journals (Sweden)

    M. N. Tijani

    2014-09-01

    Full Text Available Hydrogeochemical characterization of a weathered basement aquifer in Ilesha area, southwest Nigeria, was carried out with respect to geogenic and anthropogenic influences on the shallow groundwater system. Physico-chemical parameters revealed a pH of 6.4–8.4 and EC of 22–825 μs/cm in the urban areas compared to a pH of 7.3–10.5 and relatively higher EC of 126–1027 μs/cm in the peri-urban area. The concentrations of major cations (Ca, Na, K, Mg in the urban areas revealed relatively lower average concentrations of 28.4, 16.7, 8.4 and 5.0 mg/L, respectively, compared to 82.5, 33.4, 19.3 and 12.4 mg/L, respectively, for the peri-urban areas. The low concentrations of major cations in the urban areas can be attributed to low mineral dissolution of quartzite and muscovite quartz-schist bedrocks compared to the weathered granitic, amphibolite and biotite schist in the peri-urban areas. Hydrochemical characterization revealed two main water types; namely Ca-Mg-(Na-HCO3 mostly in the urban areas suggesting CO2-charged infiltrating recharge rainwater, and Ca-Na-(K-SO4-Cl type in the peri-urban areas as products of water–rock interactions.

  7. Application of hydrogeochemical modelling in simulating the transportation of elements in fly ash heap under different disposal systems in South Africa

    Science.gov (United States)

    Mbugua, J. M.; Ngila, J. C.; Kindness, A.; Demlie, M.

    Ash heap modelling of South African fly ash from Tutuka was carried out and the duration of transportation projected for 20 years based on two disposal scenarios, namely; irrigation of ash with rainwater, and irrigation with brines. The hydrogeochemical modeling code, PHREEQC, was applied in the study which gave insights into the speciation, release and transport of elements from the water and brines-fly ash long term interactions. Tutuka ash-water heap model showed a general sharp decrease of total elemental concentrations released during the first 2.5 years simulation as the pH value dropped from 12.6 to 8.7, after which it remained constant and their concentration remained constant up to 20 years. The elements showing this trend included Ca, Mg, Al, Fe, Sr, Zn, Na, K, Li and C(4). Generally, brines caused sharp increase in released concentration of the elements Ca, Mg, S(6) and C(4) for the first 3 years of heap irrigation whereas with water irrigation an opposite trend was observed in which the elemental concentrations decreased. Much of the release chemistry of the elements was closely related to the phase dissolution/precipitation and formation as the major controlling factors. Generally therefore, the modelled leachate quality results revealed that many elements are mobile and move through the ash heap in a progressive leaching pathway. The model could therefore be used to provide reasonable leachate quality from the modelled Tutuka ash heap which may be reaching the ground water. Overall, the ash heap modelling enhanced the understanding of the environmental impacts of ash-water-brines interactions and demonstrated that leachate composition is determined by the following factors; (i) the mass flows from the pores of fly ash, (ii) the surface dissolution of the mineral phases, (iii) the various chemical reactions involved during the ash-brine and ash-water interactions, (iv) the interactions with a gas phase (atmospheric CO2), (v) the composition of the

  8. A little island with significant groundwater resources: hydrogeological and hydrogeochemical features of the Pianosa aquifer (Tuscan Archipelago, Italy)

    Science.gov (United States)

    Giannecchini, R.; Doveri, M.; Mussi, M.; Nicotra, I.; Puccinelli, A.

    2012-12-01

    The Pianosa Island is one of the seven islands of the Tuscan Archipelago, particularly known for its typical flat morphological structure. It is formed by Neogenic-Quaternary sedimentary rocks, mainly represented by superficial calcarenite and underlying marl and clayey marl. Despite the small extension of the island (just 10,2 km2 wide, coastal perimeter of approximately 18 km, maximum altitude of 29 m a.s.l.) and poor rainfall amount (the annual average is 480,7 mm in 1951-2002 period), the Pianosa aquifer is characterized by significant groundwater resources, which supported the presence of approximately 2,000 people at the end of Eighties. Nevertheless, the groundwater overexploitation and the land use (agricultural activity and cattle-breeding, associated to the local penal settlement activity) caused important sea-water intrusion and pollution phenomena. An improvement of such situation occurs since 1998, owing to the closing of the penal settlement and its activities. This pilot research intends to describe the hydrogeological and hydrogeochemical features of the Pianosa Island aquifer system and the groundwater quality several years after the penal settlement closing. The results of a multidisciplinary approach (hydrogeological, geochemical, isotopic) show that the groundwater recharge and circulation are substantially controlled by the hydro-structural conditions. The flat and permeable superficial calcarenite allows a high infiltration rate. The water table flow direction is generally W-E, in accordance with the dip direction of the stratigraphic contact between the calcarenite and the underlying impermeable marly-clayey rocks. However, the latter present conglomerate and sandstone intercalations, sometimes in contact (by angular unconformity) with the calcarenite, determining a general continuity in groundwater circulation, which is phreatic in the calcarenite, and confined in the conglomerate and sandstone horizons. A piezometric depression with values

  9. Hydrogeochemical and Isotopic Indicators of Hydraulic Fracturing Flowback Fluids in Shallow Groundwater and Stream Water, derived from Dameigou Shale Gas Extraction in the Northern Qaidam Basin.

    Science.gov (United States)

    Zheng, Zhaoxian; Zhang, Hongda; Chen, Zongyu; Li, Xufeng; Zhu, Pucheng; Cui, Xiaoshun

    2017-06-06

    Most of the shale gas production in northwest China is from continental shale. Identifying hydrogeochemical and isotopic indicators of toxic hydraulic fracturing flowback fluids (HFFF) has great significance in assessing the safety of drinking water from shallow groundwater and streamwater. Hydrogeochemical and isotopic data for HFFF from the Dameigou shale formations (Cl/Br ratio (1.81 × 10-4-6.52 × 10-4), Ba/Sr (>0.2), δ11B (-10-1‰), and εSWSr (56-65, where εSWSr is the deviation of the 87Sr/86Sr ratio from that of seawater in parts per 104)) were distinct from data for the background saline shallow groundwater and streamwater before fracturing. Mixing models indicated that inorganic elemental signatures (Br/Cl, Ba/Sr) and isotopic fingerprints (δ11B, εSWSr) can be used to distinguish between HFFF and conventional oil-field brine in shallow groundwater and streamwater. These diagnostic indicators were applied to identify potential releases of HFFF into shallow groundwater and streamwater during fracturing, flowback and storage. The monitored time series data for shallow groundwater and streamwater exhibit no clear trends along mixing curves toward the HFFF end member, indicating that there is no detectable release occurring at present.

  10. Hydrogeological and Hydrogeochemical Modelling of the Alicun de las Torres Termal System (Province of Granada). Isotope Hydrochemistry and Gases in Groundwaters; Modelizacion Hidrogeologica e Hidrogeoquimica del Sistema Termal de Alicun de Las Torres (Provincia de Granada). Hidroquimica Isotopica y Gases en Aguas

    Energy Technology Data Exchange (ETDEWEB)

    Prado Perez, A. J.; Delgado, A.; Crespo, M. T.; Martin, A.; Vaselli, O.; Perez del Villar, L.

    2010-11-17

    In the framework of a Singular Strategic Project entitled: {sup A}dvanced Technologies of Carbon, Capture and Storage (CCS){sup ,} supported by the MICINN (Spain) and the FEDER founds (EU), specifically in the Carbon Storage Task, a comprehensive study on the CO{sub 2} leakage as DIC (Dissolved Inorganic Carbon) in the Alicun de Las Torres (Prov. of Granada) natural analogue thermal system was envisaged. This analogous system is characterised by the presence of a very important travertine formation, which can be considered as a permanent and stable sink for CO{sub 2}. In order to explain the formation of these travertine mass an hydrogeological and hydrogeochemical model of the area has been established by using the hydrochemical data, the stable and radioactive isotope characteristics, the dissolved inorganic carbon, as well as the chemical and isotopic composition of the free and dissolved gases of the above mentioned Thermal System. (Author) 11 refs.

  11. Hydro-geochemical and isotopic composition of ground water in Helwan area

    Directory of Open Access Journals (Sweden)

    W.M. Salem

    2015-12-01

    The environmental stable isotopes oxygen and hydrogen (18O, and deuterium were studied and used to identify the sources of recharge. The studied ground waters are enriched in D and 18O and the isotopic features suggest that most of the ground water recharged indirectly after evaporation prior to infiltration from irrigation return water as well as the contribution from Nile water.

  12. Hydrogeochemical variations in groundwater periodically sampled at El Hierro (Canary Islands) and its relationships with the recent eruptive and unrest periods

    Science.gov (United States)

    Luengo-Oroz, Natividad; Torres, Pedro A.; Moure, David; D'Alessandro, Walter

    2014-05-01

    . In addition, continuous CO2 measurements in the atmosphere of two galleries of the island have not shown any relevant changes since the beginning of the volcanic unrest. Taking into account this absence of significant CO2 fluxes along the whole studied period, it could be hypothesized that almost all the CO2 separated from the magma during its ascent to the surface along the different unrest processes has been dissolved in the aquifers of the island. Such finding emphasizes the important contribution that hydrogeochemical data can provide to the volcanic surveillance program of El Hierro Island.

  13. Hydrogeological, petrophysical and hydrogeochemical characteristics of the groundwater aquifers east of Wadi El-Natrun, Egypt

    Directory of Open Access Journals (Sweden)

    Zenhom E. Salem

    2016-06-01

    The concentrations of TDS and the dissolved elements are higher in the shallow groundwater compared to the deeper one, which could be related to soil salinity and evaporation processes. Ion exchange, water–rock interaction and evaporation processes are the main geochemical processes affecting the chemistry of the studied groundwater. Sodium chloride/bicarbonate types are the most common chemical types in the study area. Most of the water samples are of old meteoric origin (Na2SO4 type and old marine origin (MgCl2 type. On the basis of SAR and EC values it is concluded that most of the groundwater samples are suitable for irrigation purposes.

  14. Hydrogeological, petrophysical and hydrogeochemical characteristics of the groundwater aquifers east of Wadi El-Natrun, Egypt

    Science.gov (United States)

    Salem, Zenhom E.; El-Bayumy, Dina A.

    2016-06-01

    The studied water-bearing formations in the investigated area are the Quaternary and the Miocene aquifers. The groundwater movement takes a direction from the eastern and northern directions where the surface water sources are located to the western and southern directions. By comparing the water level data of 1960 and 2010, up to 25 m drawdown was noticed in the southern part due to excessive pumping. On the other hand, water level rising was observed in the same period reaching up to 10 m in the northwestern part due to seepage from the irrigation channel. Petrophysical properties of the studied aquifers were estimated from well logs. The formation water resistivity (Rw) averages 15.2 ohm m whereas the formation factor (F) averages 5.1. The averages of the total porosity, the effective porosity and permeability are 36.5%, 33.1% and 1126.3 mdarcy, respectively. In addition, the gamma ray logs were used to estimate the volume share of shale which showed an average value reached about 34.6%. Total porosity, effective porosity and permeability showed an increasing trend to the northwestern direction where the recharge area is located. The concentrations of TDS and the dissolved elements are higher in the shallow groundwater compared to the deeper one, which could be related to soil salinity and evaporation processes. Ion exchange, water-rock interaction and evaporation processes are the main geochemical processes affecting the chemistry of the studied groundwater. Sodium chloride/bicarbonate types are the most common chemical types in the study area. Most of the water samples are of old meteoric origin (Na2SO4 type) and old marine origin (MgCl2 type). On the basis of SAR and EC values it is concluded that most of the groundwater samples are suitable for irrigation purposes.

  15. Groundwater Quality Assessment by Using Hydrogeochemical Methods in the National Capital Territory -Delhi, India

    Science.gov (United States)

    Kumar, M.; Ramanathan, A.

    2006-05-01

    Present study has been carried out to assess the real status of groundwater, second major water resource for the drinking water supply in the National Capital Territory (NCT) of India, Delhi. Salinity and nitrate contamination are the two major problems in the area which is alarming for drinking purpose. Various graphical plots and statistical analysis has been carried out to understand the geochemical processes and its relation to the groundwater quality based on the ionic constituents, water types, hydrochemical facies and to understand nutrient chemistry (nitrate, phosphate and potassium) with spatial and seasonal variations in the groundwater nature in the study area. The concentration of nutrients in groundwater acts as an indicator to identify the nature and influence of agricultural and urban runoff on the shallow subsurface environment. Results of the study suggests that leaching from the various unlined landfill sites is the prime cause of nitrate contamination along with other factors like agricultural activities, soil mineralization processes and irrigation return flow. The result also indicates a different source of origin for the nitrate and potassium and not a common source for their origin as it was thought earlier. Local recharge is associated with low salinity of Ca- Mg-HCO3 type which is through rainfall and surface water body especially by west Yamuna canal and Yamuna River. Large lateral variation of conservative elements shows that recharge through lateral flow is not dominant in the area. Highly saline and brackish groundwater in the discharge zones like northwestern and southwestern parts of the area seem to be associated with long history of evaporation and oxidation of sulfur gases in low lying areas. In view of increasing demand of drinking water in the area, present study is vital and suggests the need of immediate management action for landfill sites.

  16. Hydrogeochemical features of groundwater resources in Tabriz plain, northwest of Iran

    Science.gov (United States)

    Barzegar, Rahim; Asghari Moghaddam, Asghar; Tziritis, Evangelos

    2017-11-01

    The present study seeks to evaluate the hydrogeochemistry of Tabriz plain in NW Iran, through major ion chemistry and their spatial variations. In order to accomplish these, groundwater sampling from 30 shallow and deep wells in the plain were carried out in July 2012. The water samples were analyzed for various physicochemical parameters such as pH, EC, Na+, Ca2+, K+, Mg2+, Cl-, CO3 2-, HCO3 -, SO4 2- and NO3 -. Chadha's diagram demonstrates that most of the groundwaters belonged to the Na-Cl and mixed Ca-Mg-Cl hydrochemical facies. The concentrations of some major ions in groundwater are above the permissible limit for drinking and domestic purposes except for a few locations. The results of saturation index computation show that dissolution of gypsum, anhydrite, halite and silicate minerals occurs frequently across the study area, whereas the groundwater is supersaturated with regard to calcite and dolomite. Cross-plots show that weathering and dissolution of different rocks and minerals, ion exchange, reverse ion exchange and anthropogenic activities, especially agricultural activities, are effective in hydrogeochemistry of the study area.

  17. Hydrogeochemical and isotopic signature of surface and groundwater in a highly industrialized sector of the Rio de la Plata coastal plain (Argentina).

    Science.gov (United States)

    Santucci, L; Carol, E; Borzi, G; García, M G

    2017-07-15

    The coastal plain of the middle estuary of the Río de la Plata is a highly industrialized area and is densely populated by sectors. The main human activity in the sector encompassed between the cities of Ensenada and Berisso is associated with the petrochemical industry. In this work, hydrogeochemical and isotopic characteristics of surface and groundwater in the impacted area are analyzed and the results are contrasted with those obtained in an undisturbed protected area. Major and trace elements were determined using standardized methods while the stable isotopes δ(18)O y δ(2)H were analyzed by mass spectroscopy. Human impact is evidenced by the occurrence of large variations in the major chemical composition of water, and also by the elevated concentrations of some trace elements that are not contributed from natural sources. These results may contribute to the understanding of chemical processes and pollutants distribution in highly industrialized coastal plain areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Hydrogeological, petrophysical and hydrogeochemical characteristics of the groundwater aquifers east of Wadi El-Natrun, Egypt

    OpenAIRE

    Zenhom E. Salem; Dina A. El-Bayumy

    2016-01-01

    The studied water-bearing formations in the investigated area are the Quaternary and the Miocene aquifers. The groundwater movement takes a direction from the eastern and northern directions where the surface water sources are located to the western and southern directions. By comparing the water level data of 1960 and 2010, up to 25 m drawdown was noticed in the southern part due to excessive pumping. On the other hand, water level rising was observed in the same period reaching up to 10 m i...

  19. Influence of hydrogeochemical processes on zero-valent iron reactive barrier performance: A field investigation

    Science.gov (United States)

    Liang, Liyuan; Moline, Gerilynn R.; Kamolpornwijit, Wiwat; West, Olivia R.

    2005-08-01

    Geochemical and mineralogical changes were evaluated at a field Fe 0-PRB at the Oak Ridge Y-12 site concerning operation performance during the treatment of U in high NO 3- groundwater. In the 5-year study period, the Fe 0 remained reactive as shown in pore-water monitoring data, where increases in pH and the removal of certain ionic species persisted. However, coring revealed varying degrees of cementation. After 3.8-year treatment, porosity reduction of up to 41.7% was obtained from mineralogical analysis on core samples collected at the upgradient gravel-Fe 0 interface. Elsewhere, Fe 0 filings were loose with some cementation. Fe 0 corrosion and pore volume reduction at this site are more severe due to the presence of NO 3- at a high level. Tracer tests indicate that hydraulic performance deteriorated: the flow distribution was heterogeneous and under the influence of interfacial cementation a large portion of water was diverted around the Fe 0 and transported outside the PRB. Based on the equilibrium reductions of NO 3- and SO 42- by Fe 0 and mineral precipitation, geochemical modeling predicted a maximum of 49% porosity loss for 5 years of operation. Additionally, modeling showed a spatial distribution of mineral precipitate volumes, with the maximum advancing from the interface toward downgradient with time. This study suggests that water quality monitoring, coupled with hydraulic monitoring and geochemical modeling, can provide a low-cost method for assessing PRB performance.

  20. Hydrogeochemical characteristics and groundwater contamination in the rapid urban development areas of Coimbatore, India

    Directory of Open Access Journals (Sweden)

    S. Selvakumar

    2017-06-01

    Full Text Available The Singanallur Sub-basin is one of the major waterways and it supplies water to the Coimbatore city. Currently, it is vulnerable to pollution due to an increase of unplanned urban developments, industrial, and agricultural activities that compromise both the quality and quantity. In the present study three major hydrochemical facies were identified (mixed Ca-Mg-Cl, Ca-Cl, and Ca-HCO3. Irrigation suitability indexes are specifies that the groundwater in the areas has very high salinity hazard and low to medium alkali hazard. The mechanism controlling groundwater chemistry originally regulated by the evaporation process is dominated by reason of arid condition and anthropogenic activities existing throughout the region. The multivariate statistical analysis (Correlation analysis (CA, principal component analysis (PCA and Hierarchical cluster analysis (HCA indicates, most of the variations are elucidated by the anthropogenic pollutant predominantly due to population growth, industrial effluents, and irrigation water return flow. This study demonstrates enhanced information of evolution of groundwater quality by integrating hydrochemical data and multivariate statistical methods are used to understand the factors influencing contamination due to natural and anthropogenic impacts.

  1. Assessment and modeling of the groundwater hydrogeochemical quality parameters via geostatistical approaches

    Science.gov (United States)

    Karami, Shawgar; Madani, Hassan; Katibeh, Homayoon; Fatehi Marj, Ahmad

    2018-03-01

    Geostatistical methods are one of the advanced techniques used for interpolation of groundwater quality data. The results obtained from geostatistics will be useful for decision makers to adopt suitable remedial measures to protect the quality of groundwater sources. Data used in this study were collected from 78 wells in Varamin plain aquifer located in southeast of Tehran, Iran, in 2013. Ordinary kriging method was used in this study to evaluate groundwater quality parameters. According to what has been mentioned in this paper, seven main quality parameters (i.e. total dissolved solids (TDS), sodium adsorption ratio (SAR), electrical conductivity (EC), sodium (Na+), total hardness (TH), chloride (Cl-) and sulfate (SO4 2-)), have been analyzed and interpreted by statistical and geostatistical methods. After data normalization by Nscore method in WinGslib software, variography as a geostatistical tool to define spatial regression was compiled and experimental variograms were plotted by GS+ software. Then, the best theoretical model was fitted to each variogram based on the minimum RSS. Cross validation method was used to determine the accuracy of the estimated data. Eventually, estimation maps of groundwater quality were prepared in WinGslib software and estimation variance map and estimation error map were presented to evaluate the quality of estimation in each estimated point. Results showed that kriging method is more accurate than the traditional interpolation methods.

  2. Influence of hydrogeochemical processes on zero-valent iron reactive barrier performance: a field investigation.

    Science.gov (United States)

    Liang, Liyuan; Moline, Gerilynn R; Kamolpornwijit, Wiwat; West, Olivia R

    2005-11-01

    Geochemical and mineralogical changes were evaluated at a field Fe0-PRB at the Oak Ridge Y-12 site concerning operation performance during the treatment of U in high NO3- groundwater. In the 5-yr study period, the Fe0 remained reactive as shown in pore water monitoring data, where increases in pH and the removal of certain ionic species persisted. However, coring revealed varying degrees of cementation. After 3.8-yr treatment, porosity reduction of up to 41.7% was obtained from mineralogical analysis on core samples collected at the upgradient gravel-Fe0 interface. Elsewhere, Fe0 filings were loose with some cementation. Fe0 corrosion and pore volume reduction at this site are more severe due to the presence of NO3- at a high level. Tracer tests indicate that hydraulic performance deteriorated: the flow distribution was heterogeneous and under the influence of interfacial cementation a large portion of water was diverted around the Fe0 and transported outside the PRB. Based on the equilibrium reductions of NO3- and SO4(2-) by Fe0 and mineral precipitation, geochemical modeling predicted a maximum of 49% porosity loss for 5 yr of operation. Additionally, modeling showed a spatial distribution of mineral precipitate volumes, with the maximum advancing from the interface toward downgradient with time. This study suggests that water quality monitoring, coupled with hydraulic monitoring and geochemical modeling, can provide a low-cost method for assessing PRB performance.

  3. Uranium in groundwater - A synopsis based on a large hydrogeochemical data set.

    Science.gov (United States)

    Riedel, Thomas; Kübeck, Christine

    2018-02-01

    Most of the knowledge on the occurrence of Uranium (U) in groundwater comes from in-situ manipulation experiments in the field, computational modelling studies or from laboratory analyses where individual processes of U mobilization were studied in isolation. Because of Uranium's vital redox chemistry it interacts, often simultaneously, with many other element cycles (e.g., sulfur, carbon, iron, and manganese) making it difficult to predict U concentrations in natural environments. For the present study a large data set was analyzed to predict the occurrence of U in groundwater from basic hydrochemistry. The data set consists of more than 8000 chemical groundwater analyses (including Uranium concentrations) from more than 2000 sampling locations. A strong relation between U concentrations and electric conductivity as well as alkalinity was observed, suggesting that weathering of geogenic source material and desorption from mineral surfaces is the principle mechanism of U release. Except for aquifers with strongly reducing conditions this process leads to a slow but continuous accumulation of U in groundwater in most cases. Importantly, the occurrence of U is modulated by the prevailing redox conditions in an aquifer. Uranium concentrations were moderate under oxic conditions and highest under manganese and nitrate-reducing conditions (heterotrophic as wells as autotrophic nitrate reduction). Only in iron- and sulfate-reducing groundwater the probability of U concentrations above 1 μg l -1 was virtually zero, as these ground waters act as U sinks. The combination of mineral weathering (especially carbonates) with mobilization of U under manganese and nitrate reducing conditions results in the highest risk of detecting U. In contrast, a low risk is associated with low pH (<7) and low mineralization of groundwater, which is the case in granitic catchments, for example. Our results further provide evidence, that agricultural practices such as liming, use of

  4. Hydrogeochemical and stream sediment special reconnaissance report for the Deep Creek Mountains, Nevada and Utah

    Energy Technology Data Exchange (ETDEWEB)

    Qualheim, B.

    1979-04-01

    This report represents the results of the reconnaissance sampling of the Deep Creek Mountains of western Utah. The Deep Creek range is located in the northwest corner of the Delta NTMS 1:250,000 and the southwestern corner of the Tooele NTMS 1:250,000 sheets and covers an area of 1750 km/sup 2/. Samples collected in this study include dry and wet stream sediments and water from available streams, wells, and springs. The samples were analyzed for uranium, as well as 15 to 20 trace elements, using neutron activation techniques. In addition, field and laboratory measurements were made on the water samples. Analytical data and field measurements are presented in tabular hard copy and fiche format. Water-sample site locations, water-sample uranium concentrations, sediment-sample site locations, and sediment-sample uranium concentrations are shown on separate overlays.

  5. Users` manual for LEHGC: A Lagrangian-Eulerian Finite-Element Model of Hydrogeochemical Transport Through Saturated-Unsaturated Media. Version 1.1

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Gour-Tsyh [Pennsylvania State Univ., University Park, PA (United States). Dept. of Civil and Environmental Engineering; Carpenter, S.L. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Earth and Planetary Sciences; Hopkins, P.L.; Siegel, M.D. [Sandia National Labs., Albuquerque, NM (United States)

    1995-11-01

    The computer program LEHGC is a Hybrid Lagrangian-Eulerian Finite-Element Model of HydroGeo-Chemical (LEHGC) Transport Through Saturated-Unsaturated Media. LEHGC iteratively solves two-dimensional transport and geochemical equilibrium equations and is a descendant of HYDROGEOCHEM, a strictly Eulerian finite-element reactive transport code. The hybrid Lagrangian-Eulerian scheme improves on the Eulerian scheme by allowing larger time steps to be used in the advection-dominant transport calculations. This causes less numerical dispersion and alleviates the problem of calculated negative concentrations at sharp concentration fronts. The code also is more computationally efficient than the strictly Eulerian version. LEHGC is designed for generic application to reactive transport problems associated with contaminant transport in subsurface media. Input to the program includes the geometry of the system, the spatial distribution of finite elements and nodes, the properties of the media, the potential chemical reactions, and the initial and boundary conditions. Output includes the spatial distribution of chemical element concentrations as a function of time and space and the chemical speciation at user-specified nodes. LEHGC Version 1.1 is a modification of LEHGC Version 1.0. The modification includes: (1) devising a tracking algorithm with the computational effort proportional to N where N is the number of computational grid nodes rather than N{sup 2} as in LEHGC Version 1.0, (2) including multiple adsorbing sites and multiple ion-exchange sites, (3) using four preconditioned conjugate gradient methods for the solution of matrix equations, and (4) providing a model for some features of solute transport by colloids.

  6. Advances in Hydrogeochemical Indicators for the Discovery of New Geothermal Resources in the Great Basin, USA

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Stuart F. [Colorado School of Mines, Golden, CO (United States). Geology and Geological Engineering; Spycher, Nicolas [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division; Sonnenthal, Eric [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division; Dobson, Patrick [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division

    2013-05-20

    This report summarizes the results of Phase I work for a go/no go decision on Phase II funding. In the first objective, we assessed the extent to which fluid-mineral equilibria controlled deep water compositions in geothermal systems across the Great Basin. Six systems were evaluated: Beowawe; Desert Peak; Dixie Valley; Mammoth; Raft River; Roosevelt. These represent a geographic spread of geothermal resources, in different geological settings and with a wide range of fluid compositions. The results were used for calibration/reformulation of chemical geothermometers that reflect the reservoir temperatures in producing reservoirs. In the second objective, we developed a reactive -transport model of the Desert Peak hydrothermal system to evaluate the processes that affect reservoir fluid geochemistry and its effect on solute geothermometry. This included testing geothermometry on “reacted” thermal water originating from different lithologies and from near-surface locations where the temperature is known from the simulation. The integrated multi-component geothermometer (GeoT, relying on computed mineral saturation indices) was tested against the model results and also on the systems studied in the first objective.

  7. Influence of Humic Acid on the Transport and Deposition of Colloidal Silica under Different Hydrogeochemical Conditions

    Directory of Open Access Journals (Sweden)

    Jingjing Zhou

    2016-12-01

    Full Text Available The transport and deposition of colloids in aquifers plays an important role in managed aquifer recharge (MAR schemes. Here, the processes of colloidal silica transport and deposition were studied by displacing groundwater with recharge water. The results showed that significant amounts of colloidal silica transport occurred when native groundwater was displaced by HA solution. Solution contains varying conditions of ionic strength and ion valence. The presence of humic acid could affect the zeta potential and size of the colloidal silica, which led to obvious colloidal silica aggregation in the divalent ion solution. Humic acid increased colloidal silica transport by formation of non-adsorbing aqueous phase silica–HA complexes. The experimental and modeling results showed good agreement, indicating that the essential physics were accurately captured by the model. The deposition rates were less than 10−8 s−1 in deionized water and monovalent ion solution. Moreover, the addition of Ca2+ and increase of IS resulted in the deposition rates increasing by five orders of magnitude to 10−4 s−1. In all experiments, the deposition rates decreased in the presence of humic acid. Overall, the promotion of humic acid in colloidal silica was strongly associated with changes in water quality, indicating that they should receive greater attention during MAR.

  8. Isotopic and Hydrogeochemical Assessment of Groundwater quality of Punjab and Haryana, India.

    Science.gov (United States)

    Jyoti, V.; Douglas, E. M.; Hannigan, R.; Schaaf, C.; Moore, J.

    2016-12-01

    Punjab and Haryana lie in the semi-arid region of northwestern India and are characterized by a limited access to freshwater resources and an increasing dependence on groundwater resources to meet human demand, resulting in overexploitation. The objectives of the present study was to characterize groundwater recharge sources using stable isotopes of (δ2H) and (δ18O) and to trace geochemical evolution of groundwater using rare earth elements (REEs). Samples were collected from 30 different locations including shallow domestic handpumps, deep irrigation wells, surface water and rainwater. Samples were analyzed for stable isotopes of (δ2H) and (δ18O) using Isotope Ratio Mass Spectrometry (IRMS) and trace elements using Inductively Coupled Plasma Mass Spectrometry (ICPMS) at University of Massachusetts Boston. Precipitation, surface water and irrigation return flow were identified as the primary sources of recharge to groundwater. Sustainability of recharge sources is highly dependent on the glacier-fed rivers from the Himalayas that are already experiencing impacts from climate change. Geochemistry of REEs revealed geochemically evolved groundwater system with carbonate subsurface weathering as major hydrological processes. Enhanced dissolution of carbonates in the future can be a serious issue with extremely hard groundwater leaving scaly deposits inside pipes and wells. This would not only worsen the groundwater quality but would impose financial implications on the groundwater users in the community. If irrigated culture is to survive as an economically viable and environmentally sustainable activity in the region, groundwater management activities have to be planned at the regional scale.

  9. Analysis of hydrogeochemical facies in groundwater of upper part of Cross River Basin, southeastern Nigeria

    Science.gov (United States)

    Stephen, Ukpai N.; Celestine, Okogbue O.; Solomon, Onwuka O.

    2017-07-01

    Upper Cross River Hydrogeological Basin lies within latitudes 60 021N to 60 241N and longitudes 80 001E to 80 161E, and is generally underlain by shales of Asu River group of Albian age. The area has Histories of intensive mineralization which influenced groundwater system, resulting to occurrence of different water types. This study determines the various water types via evaluation of major ion concentration from representative water samples collected across the area. Twenty (20) water samples were analyzed using Spectrophotometer of HACH DR/2010 series, and results showed that groundwater in the area is generally hard and polluted with TDS in some places. Statistical inspection was performed on the results using aqua-chem, and it delineated five hydro-chemical facies, namely: Ca-Mg-Cl-S04, Ca-Mg-HCO3-Cl-SO4, Ca-Mg-HCO3, Na-K-HCO3 and Na-K-Cl-SO4; all lie between slight acidic and weak alkaline water. These chemical facies (water types) diffused from non-point sources in urban area and point source from south of Abakaliki town. The dispersion of the facies plumes is possibly controlled by advection process through structural weak zones such as fractures. Hydraulic heads determined from hand-dug wells indicate local potentiometric surfaces, hence, showed local groundwater flow system which is possibly controlled by the underlying low permeable aquicludes formed by shales. The protective capacity of the aquitards was somewhat reduced by the permeating fractures which exposed the aquifers to polluting effects of mineralized water-types.

  10. Geological and hydrogeochemical controls on radium isotopes in groundwater of the Sinai Peninsula, Egypt.

    Science.gov (United States)

    Sherif, Mahmoud I; Lin, Jiajia; Poghosyan, Armen; Abouelmagd, Abdou; Sultan, Mohamed I; Sturchio, Neil C

    2017-09-20

    Radium isotopes ((226)Ra and (228)Ra) were analyzed in 18 groundwater samples from the Nubian Sandstone Aquifer System (NSAS) and the shallow alluvial aquifers overlying the basement complex of the Sinai Peninsula, Egypt. Groundwater samples from deep Nubian aquifer wells (total depths 747 to 1250m) have (226)Ra and (228)Ra activities ranging from 0.168 to 0.802 and 0.056 to 1.032Bq/L, respectively. The shallower Nubian aquifer wells (63 to 366m) have (226)Ra and (228)Ra activities ranging from 0.033 to 0.191 and 0.029 to 0.312Bq/L, respectively. The basement shallow alluvial aquifers have (226)Ra and (228)Ra activities ranging from 0.014 to 0.038 and 0.007 to 0.051Bq/L, respectively. Combined Ra activities in most wells were generally in excess of the US Environmental Protection Agency (EPA), the European Union (EU), and the World Health Organization (WHO) maximum contaminant levels (MCL) for drinking water. Radium in groundwater is produced mainly by decay of parent nuclides in the aquifer solids, and observed activities of dissolved Ra isotopes result from a combination of alpha-recoil, adsorption/desorption, co-precipitation/dissolution processes. The observed correlation between Ra activities and salinity indicates that adsorption/desorption processes may be the dominant factor controlling Ra mobility in Sinai groundwater. Radium activities in central and northern Sinai are generally higher than those in southern Sinai, consistent with a gradual increase in salinity and water-rock interaction with increasing groundwater age. Barite is approximately saturated in the groundwater and may limit maximum dissolved Ra concentration. The results of this study indicate that Sinai groundwater should be used with caution, possibly requiring Ra removal from water produced for domestic and agricultural consumption. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Hydrogeochemical processes controlling water and dissolved gas chemistry at the Accesa sinkhole (southern Tuscany, central Italy

    Directory of Open Access Journals (Sweden)

    Franco Tassi

    2014-05-01

    Full Text Available The 38.5 m deep Lake Accesa is a sinkhole located in southern Tuscany (Italy that shows a peculiar water composition, being characterized by relatively high total dissolved solids (TDS values (2 g L-1 and a Ca(Mg-SO4 geochemical facies. The presence of significant amounts of extra-atmospheric gases (CO2 and CH4, which increase their concentrations with depth, is also recognized. These chemical features, mimicking those commonly shown by volcanic lakes fed by hydrothermal-magmatic reservoirs, are consistent with those of mineral springs emerging in the study area whose chemistry is produced by the interaction of meteoric-derived waters with Mesozoic carbonates and Triassic evaporites. Although the lake has a pronounced thermocline, water chemistry does not show significant changes along the vertical profile. Lake water balance calculations demonstrate that Lake Accesa has >90% of its water supply from sublacustrine springs whose subterranean pathways are controlled by the local structural assessment that likely determined the sinking event, the resulting funnel-shape being then filled by the Accesa waters. Such a huge water inflow from the lake bottom (~9·106 m3 yr-1 feeds the lake effluent (Bruna River and promotes the formation of water currents, which are able to prevent the establishment of a vertical density gradient. Consequently, a continuous mixing along the whole vertical water column is established. Changes of the drainage system by the deep-originated waters in the nearby former mining district have strongly affected the outflow rates of the local mineral springs; thus, future intervention associated with the ongoing remediation activities should carefully be evaluated to preserve the peculiar chemical features of Lake Accesa.

  12. Radiogenic and Stable Isotope and Hydrogeochemical Investigation of Groundwater, Pajarito Plateau and Surrounding Areas, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Patrick Longmire, Michael Dale, Dale Counce, Andrew Manning, Toti Larson, Kim Granzow, Robert Gray, and Brent Newman

    2007-07-15

    From October 2004 through February 2006, Los Alamos National Laboratory, the New Mexico Environment Department-Department of Energy Oversight Bureau, and the United States Geological Survey conducted a hydrochemical investigation. The purpose of the investigation was to evaluate groundwater flow paths and determine groundwater ages using tritium/helium-3 and carbon-14 along with aqueous inorganic chemistry. Knowledge of groundwater age and flow paths provides a technical basis for selecting wells and springs for monitoring. Groundwater dating is also relevant to groundwater resource management, including aquifer sustainability, especially during periods of long-term drought. At Los Alamos, New Mexico, groundwater is either modern (post-1943), submodern (pre-1943), or mixed (containing both pre- and post-1943 components). The regional aquifer primarily consists of submodern groundwater. Mixed-age groundwater results from initial infiltration of surface water, followed by mixing with perched alluvial and intermediate-depth groundwater and the regional aquifer. No groundwater investigation is complete without using tritium/helium-3 and carbon-14 dating methods to quantify amounts of modern, mixed, and/or submodern components present in samples. Computer models of groundwater flow and transport at Los Alamos should be calibrated to groundwater ages for perched intermediate zones and the regional aquifer determined from this investigation. Results of this study clearly demonstrate the occurrence of multiple flow paths and groundwater ages occurring within the Sierra de los Valles, beneath the Pajarito Plateau, and at the White Rock Canyon springs. Localized groundwater recharge occurs within several canyons dissecting the Pajarito Plateau. Perched intermediate-depth groundwater and the regional aquifer beneath Pueblo Canyon, Los Alamos Canyon, Sandia Canyon, Mortandad Canyon, Pajarito Canyon, and Canon de Valle contain a modern component. This modern component consists

  13. Monitoring hydrogeochemical interactions in coastal mangroves in Everglades National Park using field spectroscopy and remote sensing

    Science.gov (United States)

    Lagomasino, D.; Price, R. M.; Campbell, P. K.

    2011-12-01

    Coastal tropical and subtropical environments, where there are distinct seasonal shifts in precipitation, can be highly susceptible to environmental changes caused by increasing anthropogenic pressure (e.g., urbanization, deforestation) in addition to natural "press and pulse" events, such as sea-level rise, tropical storms, and a changing climate. These man-made and natural perturbations directly affect the quality and quantity of water flowing through the ecosystem, both on the surface and subsurface. Changes in groundwater and surface water interactions will impact ecological communities, including highly vulnerable coastal mangrove communities. Nearly 1,445 km2 of mangroves cover Everglades National Park along the southern and southwestern coast of Florida. Rising sea levels, a predicted drier climate, and increased water demand may accelerate the landward migration of salt water intrusion which poses threats to the ecological communities along this coastal ecotone. This is a growing concern for the region and it is necessary that we understand the present hydrogeologic conditions to better monitor and model the future and inevitable changes to the coastal environment. The purpose of this preliminary study was to test the feasibility of measuring water quality indirectly from the spectral responses of mangrove vegetation on a regional scale. Spectra-derived biophysical indices were used to assess various relationships between the spectral signatures of the 3 main mangrove species (i.e., Avicennia germinans, Rhizophora mangle, and Laguncularia racemosa) and the ionic and nutrient concentrations in the porewater (i.e., 20cm and 100cm depths), surface water, and groundwater of the mangrove ecotone. Water samples from these sources were collected during the dry season, a transitional period, and the wet season at three sites in large, high-biomass mangroves along Shark River and two sites in dwarf, low-biomass, mangroves along Taylor River. Water samples were

  14. Hydrogeochemical Investigation of the Standard Mine Vicinity, Upper Elk Creek Basin, Colorado

    Science.gov (United States)

    Manning, Andrew H.; Verplanck, Philip L.; Mast, M. Alisa; Wanty, Richard B.

    2008-01-01

    metals were typically low and pH values were circumneutral at surrounding locations. Metal concentrations in samples collected from underground workings in the Standard Mine were also generally higher than in samples collected at aboveground sites located outside of sulfide-rich areas. Metal concentrations in discharge from the Level 1 tunnel were among the highest measured in Elk Basin. All of these observations suggest that sulfide-rich mineralized rock is the primary control on dissolved metal concentrations and pH in ground water in the Standard Mine vicinity. Waste-rock piles apparently exert another major control on metal concentrations and pH; the lowest pH and highest metal concentrations typically are found in discharge from waste-rock piles. Concentrations of several chemical constituents along with strontium isotope data indicate that none of the sampled waters could have been the primary source of metals in discharge from Level 1. Therefore, this study did not identify the primary source location for metals in Level 1 discharge. Possible sources must be located below Levels 3 and 5 or farther back into the mountainside than the ends of Levels 3 and 5. Apparent tritium/helium-3 ground-water ages ranged from 0 to 9 yr, and a considerable majority were water in the Standard Mine vicinity was weeks to months old rather than years old. Tritium, d2H, and d18O data from water entering into and discharging from the Standard Mine displayed spatial and temporal patterns indicating that these tracers were influenced by seasonal variations in their concentration in precipitation. The tracer data therefore suggest that ground water entering into and discharging from the Standard Mine was largely composed of water <1 yr old. Pronounced seasonal variations in geochemistry in Level 1 discharge also are consistent with short r

  15. Hydrogeochemical data as a tool for exploration and mapping: a case study from part of Afikpo Basin southeastern Nigeria.

    Science.gov (United States)

    Ibe, Kalu K; Akaolisa, Casmir C Z

    2010-01-01

    Fourteen (14) characters from six (6) water samples collected from springs, ponds, and streams located in Lower Cretaceous sedimentary area of Afikpo Basin have been analyzed. These include pH, turbidity, conductivity, total dissolved solid, hardness, Fe2+, Ca2+, Mg2+, K+, NO3-, Cl-, SO4(2-), and Na+. These sediments, which are Turonian and Coniacian in age, are subdivided into two by a basic rock dyke. Results of the analyses show clearly that the Turonian sediments, intruded by dolerite, have net Fe2+, HCO3-, Ca2+, Mg2+, Mn2+, Cl-, and SO4(2-) concentration while those from the younger Coniacian sediment have net higher amounts of K+, Na+, and Mn2+. The overriding mafic minerals in the basic intrusive rock possibly led to higher leaching into ground water system near it. On the other hand, the presence of feldsparthic to kaolinitic sands of the younger Coniacian units led to higher K+ and Na+ matter in the water from these zones. The formations dip away from the older sediments. Concentrations of these characters are within acceptable drinking water standards by World Health Organization but noticeable anomalous zones for Fe2+, Mg2+, and Ca2+ are zones of basic rock suites. Areas with greater Na+ and K+ are traceable to sandy units. It is thus concluded that more analysis of surface, subsurface, and pond water samples can be utilized for minerals search and geological mapping. At this stage, it forms a veritable reconnaissance tool.

  16. Main constraints for siting monitoring networks devoted to the study of earthquake related hydrogeochemical phenomena in Italy

    Directory of Open Access Journals (Sweden)

    D. Albarello

    1997-06-01

    Full Text Available Criteria and data useful to select test sites in Italy suitable for monitoring earthquake related fluctuations in geofluid natural emissions are given. For this purpose, a catalogue of thermically anomalous natural springs was compiled on the basis of recent and old documentary sources. This catalogue, reporting more than 1200 localities, can be used to identify those sites where gas-fluid emissions are presumably representative of deep water circulation. A catalogue of CO2 gas reservoirs exploited in the past and at present for industrial extraction was also compiled to identify all the areas where strong degassing activity may affect spring sources and generate enhanced water-rock interaction processes. To complete this review, data were also collected on natural springs characterized, on the basis of documentary sources, by "anomalous" behaviour during past earthquakes. An independent constraint to select the most interesting test sites was obtained by the analysis of seismic activity in this century. In this way, a number of sites were identified where it is likely to observe at least one significant earthquake (with magnitude ³ 3.5 within 20 km during a 3 year monitoring interval. These pieces of information were matched and three areas, respectively located in the Central Apennines, Southern Apennines and Sicily were identified as the most promising test sites for monitoring geofluid emissions as markers of active seismogenic processes.

  17. An analytical method for hydrogeochemical surveys: Inductively coupled plasma-atomic emission spectrometry after using enrichment coprecipitation with cobalt and ammonium pyrrolidine dithiocarbamate

    Science.gov (United States)

    Hopkins, D.M.

    1991-01-01

    Trace metals that are commonly associated with mineralization were concentrated and separated from natural water by coprecipitation with ammonium pyrollidine dithiocarbamate (APDC) and cobalt and determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The method is useful in hydrogeochemical surveys because it permits preconcentration near the sample sites, and selected metals are preserved shortly after the samples are collected. The procedure is relatively simple: (1) a liter of water is filtered; (2) the pH is adjusted; (3) Co chloride and APDC are added to coprecipitate the trace metals; and (4) later, the precipitate is filtered, dissolved, and diluted to 10 ml for a 100-fold concentration enrichment of the separated metals. Sb(III), As(III), Cd, Cr, Cu, Fe, Pb, Mo, Ni, Ag, V, and Zn can then be determined simultaneously by ICP-AES. In an experiment designed to measure the coprecipitation efficiency, Sb(III), Cd and Ag were recovered at 70 to 75% of their original concentration. The remaining metals were recovered at 85 to 100% of their original concentrations, however. The range for the lower limits of determination for the metals after preconcentration is 0.1 to 3.0 ??g/l. The precision of the method was evaluated by replicate analyses of a Colorado creek water and two simulated water samples. The accuracy of the method was estimated using a water reference standard (SRM 1643a) certified by the U.S. National Bureau of Standards. In addition, the method was evaluated by analyzing groundwater samples collected near a porphyry copper deposit in Arizona and by analyzing meltwater from glacier-covered areas favorable for mineralization in south-central Alaska. The results for the ICP-AES analyses compared favorably with those obtained using the sequential technique of GFAAS on the acidified but unconcentrated water samples. ICP-AES analysis of trace-metal preconcentrates for hydrogeochemical surveys is more efficient than GFAAS because a

  18. Characterization of Recharge Mechanisms and Sources of Groundwater Salinization in Ras Jbel Coastal Aquifer (Northeast Tunisia Using Hydrogeochemical Tools, Environmental Isotopes, GIS, and Statistics

    Directory of Open Access Journals (Sweden)

    Jamila Hammami Abidi

    2017-01-01

    Full Text Available Groundwater is among the most available water resources in Tunisia; it is a vital natural resource in arid and semiarid regions. Located in north-eastern Tunisia, the Metline-Ras Jbel-Raf Raf aquifer is a mio-plio-quaternary shallow coastal aquifer, where groundwater is the most important source of water supply. The major ion hydrochemistry and environmental isotope composition (δ18O, δ2H were investigated to identify the recharge sources and processes that affect the groundwater salinization. The combination of hydrogeochemical, isotopic, statistical, and GIS approaches demonstrates that the salinity and the groundwater composition are largely controlled by the water-rock interaction particularly the dissolution of evaporate minerals and the ion exchange process, the return flow of the irrigation water, agricultural fertilizers, and finally saltwater intrusion which started before 1980 and which is partially mitigated by the artificial recharge since 1993. As for the stable isotope signatures, results showed that groundwater samples lay on and around the local meteoric water line LMWL; hence, this arrangement signifies that the recharge of the Ras Jbel aquifer is ensured by recent recharge from Mediterranean air masses.

  19. Integrated investigation of seawater intrusion around oil storage caverns in a coastal fractured aquifer using hydrogeochemical and isotopic data

    Science.gov (United States)

    Lim, Jeong-Won; Lee, Eunhee; Moon, Hee Sun; Lee, Kang-Kun

    2013-04-01

    SummarySeawater intrusion can be activated by the construction of underground caverns which act as groundwater sinks near a coastal area. In an environment complicated with such artificial structures, seawater intrusion is not simple and thus needs to be evaluated by means of multiple analytical approaches. This study uses geochemical and isotopic indicators to assess the characteristics of salinized seepage into an underground oil storage cavern in Yeosu, Korea. Cl-/Br- ratios, principal component analysis (PCA) of chemical data, and stable isotope data were used to determine the origin and the extent of salinization. Indications of seawater intrusion into the cavern through fractured bedrocks were observed; however, it was highly probable that another source may have contributed to the observed salinity. The PCA results revealed that the seepage water chemistry was predominantly affected both by seawater mixing and cement material dissolution. The maximum seawater mixing ratio in the seepage water was estimated on the basis of the Cl--Br- mixing ratio and the Cl--δ18O relation, with the results showing considerable variation ranging from less than 1% to as high as 14%, depending on the cavern location. The spatial variations in the chemical characteristics and in mixing ratios are believed to have resulted from the hydrogeological heterogeneity of the study site, as caused by both fractured aquifer and the cavern facilities.

  20. Hydrogeochemical Characteristics and Evolution of Hot Springs in Eastern Tibetan Plateau Geothermal Belt, Western China: Insight from Multivariate Statistical Analysis

    Directory of Open Access Journals (Sweden)

    Zheming Shi

    2017-01-01

    Full Text Available The eastern Tibetan Plateau geothermal belt is one of the important medium-high temperature geothermal belts in China. However, less work has been done on the hydrochemical characteristic and its geological origin. Understanding the chemical characteristics and the hydrochemical evolution processes is important in evaluating the geothermal energy potential in this area. In the present study, we discussed the hydrochemical properties and their origins of 39 hot springs located in the eastern Tibetan Plateau geothermal belt (Kangding-Litang-Batang geothermal belt. Cluster analysis and factor analysis are employed to character the hydrochemical properties of hot springs in different fault zones and the possible hydrochemical evolution processes of these hot springs. Our study shows that the hot springs can be divided into three groups based on their locations. The hot springs in the first group mainly originate from the volcanic rock and the springs in the second group originate from the metamorphic rock while the springs in the third group originate from the result of mixture of shallow water. Water-rock interaction, cation exchange, and the water environment are the three dominant factors that control the hydrochemical evolution process in the eastern Tibetan Plateau. These results are also in well agreement with the isotopic and chemical analysis.

  1. Hydrogeochemical and stable isotope geochemical characterization of shallow ground waters and submarine ground water discharge in North-Eastern Germany

    Science.gov (United States)

    Böttcher, Michael E.; Schmiedinger, Iris; Böttcher, Gerd; Schwerdtfeger, Beate; Lipka, Marko; Westphal, Julia

    2017-04-01

    The evolution and hydrochemical composition of ground waters in Mecklenburg-Western Pommerania (North-Eastern Germany) is controlled by different natural and anthropogenic factors. In the present study, the hydrogeochemistry and stable isotope geochemistry (H, C, O, S) of shallow ground waters was investigated in 2014 and 2015. A mass balance approach is combined with physico-chemical modeling to define the mineral dissolution/precipitation potential as well as the processes taking place during the ground water development. The dissolved inorganic carbon system of the ground waters is controlled by the dissolution of biogenic carbon dioxide, the dissolution of (marine) carbonates and the oxidation of anthropogenically introduced DOC and at a few sites biogenic methane. The sulfur isotope composition of dissolved sulfate indicates the substantial impact from the oxidation of sedimentary pyrite using oxygen or nitrate as electron acceptor. The combined results are the base for a quantitative reaction path analysis. The composition of ground water is discussed with respect to its role as a source for fresh waters forming SGD and in a re-wetting wetland area (Hütelmoor) at the southern Baltic Sea coast line. Acknowledgements: The SGD/Hütelmoor part of this study is supported by German Science Foundation during DFG research training group BALTIC TRANSCOAST.

  2. Identification of earthquake precursors in the hydrogeochemical and geoacoustic data for the Kamchatka peninsula by flicker-noise spectroscopy

    CERN Document Server

    Ryabinin, G V; Gavrilov, V A; Timashev, S F

    2011-01-01

    A phenomenological systems approach for identifying potential precursors in multiple signals of different types for the same local seismically active region is proposed based on the assumption that a large earthquake may be preceded by a system reconfiguration (preparation) at different time and space scales. A nonstationarity factor introduced within the framework of flicker-noise spectroscopy, a statistical physics approach to the analysis of time series, is used as the dimensionless criterion for detecting qualitative (precursory) changes within relatively short time intervals in arbitrary signals. Nonstationarity factors for chlorine-ion concentration variations in the underground water of two boreholes on the Kamchatka peninsula and geacoustic emissions in a deep borehole within the same seismic zone are studied together in the time frame around a large earthquake on October 8, 2001. It is shown that nonstationarity factor spikes (potential precursors) take place in the interval from 70 to 50 days before...

  3. Natural attenuation of chlorinated-hydrocarbon contamination at Fort Wainwright, Alaska; a hydrogeochemical and microbiological investigation workplan

    Science.gov (United States)

    McCarthy, Kathleen A.; Lilly, Michael R.; Braddock, Joan F.; Hinzman, Larry D.

    1998-01-01

    Natural attenuation processes include biological degradation, by which microorganisms break down contaminants into simpler product compounds; adsorption of contaminants to soil particles, which decreases the mass of contaminants dissolved in ground water; and dispersion, which decreases dissolved contaminant concentrations through dilution. The primary objectives of this study are to (1) assess the degree to which such natural processes are attenuating chlorinated-hydrocarbon contamination in ground water, and (2) evaluate the effects of ground-water/surface-water interactions on natural-attenuation processes in the area of the former East and West Quartermasters Fueling Systems for Fort Wainwright, Alaska. The study will include investigations of the hydrologic, geochemical, and microbiological processes occurring at this site that influence the transport and fate of chlorinated hydrocarbons in ground water. To accomplish these objectives, a data-collection program has been initiated that includes measurements of water-table elevations and the stage of the Chena River; measurements of vertical temperature profiles within the subsurface; characterization of moisture distribution and movement in the unsaturated zone; collection of ground-water samples for determination of both organic and inorganic chemical constituents; and collection of ground-water samples for enumeration of microorganisms and determination of their potential to mineralize contaminants. We will use results from the data-collection program described above to refine our conceptual model of hydrology and contaminant attenuation at this site. Measurements of water-table elevations and river stage will help us to understand the magnitude and direction of ground-water flow and how changes in the stage of the Chena River affect ground-water flow. Because ambient ground water and surface water typically have different temperature characteristics, temperature monitoring will likely provide further insight

  4. Assessing the hydrogeochemical processes affecting groundwater pollution in arid areas using an integration of geochemical equilibrium and multivariate statistical techniques.

    Science.gov (United States)

    El Alfy, Mohamed; Lashin, Aref; Abdalla, Fathy; Al-Bassam, Abdulaziz

    2017-10-01

    Rapid economic expansion poses serious problems for groundwater resources in arid areas, which typically have high rates of groundwater depletion. In this study, integration of hydrochemical investigations involving chemical and statistical analyses are conducted to assess the factors controlling hydrochemistry and potential pollution in an arid region. Fifty-four groundwater samples were collected from the Dhurma aquifer in Saudi Arabia, and twenty-one physicochemical variables were examined for each sample. Spatial patterns of salinity and nitrate were mapped using fitted variograms. The nitrate spatial distribution shows that nitrate pollution is a persistent problem affecting a wide area of the aquifer. The hydrochemical investigations and cluster analysis reveal four significant clusters of groundwater zones. Five main factors were extracted, which explain >77% of the total data variance. These factors indicated that the chemical characteristics of the groundwater were influenced by rock-water interactions and anthropogenic factors. The identified clusters and factors were validated with hydrochemical investigations. The geogenic factors include the dissolution of various minerals (calcite, aragonite, gypsum, anhydrite, halite and fluorite) and ion exchange processes. The anthropogenic factors include the impact of irrigation return flows and the application of potassium, nitrate, and phosphate fertilizers. Over time, these anthropogenic factors will most likely contribute to further declines in groundwater quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Hydrogeochemical and geophysical investigation of the Istanbul Tuzla-Icmeler spring area for environmental and land use planning purposes.

    Science.gov (United States)

    Yalcin, Tolga; Ozürlan, Gülcin; Cekirge, Nevin

    2007-09-01

    The spring waters of Tuzla-Icmeler are on the Marmara Sea coast in Tuzla town of Istanbul city. The springs discharge a natural sodium chloride mineral water that consumed for ages for therapeutic purposes attributed to their chemical properties. Development of springs commenced during the Ottoman times and a surface collection structure was built at the discharge point of the main spring. Two deep wells were drilled to tap mineral water within the past decades. The bottled water of these springs is also sold for a couple of years and its consumption as a beverage is increasing. The geochemical properties of these springs were investigated by several researchers in the past. This study comprises geochemical and geophysical measurements performed between July 2001 and July 2002 in order to construct a conceptual hydrogeological model for environmental and land use planning purposes. The seasonal evaluation of Tuzla-Icmeler (mineral spring) shows that the chemical properties fluctuate from the beginning of summer until the beginning of winter. This indicates that the overdraft of water during the summer season causes the movement and mix of normal groundwater with the mineralized groundwater. As a result, mixing of less mineralized groundwater decreases the salinity of mineralized groundwater. Using the site-specific hydrogeological, geochemical and geophysical data, zones of protection areas were delineated in order to prevent a possible pollution access to the springs and surroundings from nearby dockyards, dwellings and vehicle traffic. For this purpose, a new land use plan was proposed using the existing settlement sustainability plans.

  6. Hydrogeological, Hydrogeochemical and Isotope Geochemical Features of the Geothermal Waters in Seferihisar and Environs, Western Anatolia, Turkey

    Science.gov (United States)

    Özgür, Nevzat; Aras Pala, Ebru; Degirmenci, Saliha

    2017-12-01

    The study area of Seferihisar is located within the Izmir-Ankara suture in the NW of the Menderes Massif in western Anatolia, Turkey. The Paleozoic metamorphic rocks of the Menderes Massif form the basement rocks in the area which are overlain by 760 m thick Izmir-flysch series consisting of metamorphic rocks, limestones and ultrabasic rocks tectonically. The Pliocene Bahçecik formation which consists of an alternation of conglomerates, sandstones, claystones, lignite and limestones and shows a thickness of 300 m overlies the (İzmir) flysch series discordantly. This is overlain by 430 m thick Yeniköy formation composed of conglomerates, sandstones, claystones and clayey limestones discordantly. The Miocene volcanic rocks of Cumaovası overlie the Yeniköy formation concordantly which are overlain by alluvium and travertine deposits. Geothermal waters which are observed in the localities of Tuzla, Cumalı, Doğanbey and Karakoç are associated with NE-SW trending faults in the area. The geothermal waters in the area are considered as Na-Cl or Na-Cl-HCO3 type waters. The geothermal waters of Seferihisar and environs are identified to be Na+K>Ca>Mg dominant cations and Cl>HCO3>SO4 dominant anions. According to the diagram of Na/100-K/100-√Mg, a certainly part of the thermal waters can be considered as equilibrated thermal waters during some waters are of immature waters. According to the results of geochemical thermometers, the reservoir temperatures of thermal waters range from 150 to 240°C. The δ2H values of thermal waters are between -13,3 to -31,9, while δ18O values range from -2,55 to -5,70. The tritium contents of thermal waters are between 13 to 64±10 TU.

  7. Integrated hydrogeochemical, isotopic and geomorphological depiction of the groundwater salinization in the aquifer system of Delhi, India

    Science.gov (United States)

    Kumar, Manish; Rao, M. Someshwar; Deka, Jyoti Prakash; Ramanathan, AL.; Kumar, Bhishm

    2015-11-01

    The problem of salinization in the Delhi aquifer, that currently exhibits rapid landuse change, is conspicuous and severe. Salinization may be caused either by a single process, or a combination of different processes; including anthropogenic related activities, water logging and evaporative concentration of salts, influx of natural saline water, upconing of brines from the deeper parts of the aquifer, and airborne salts depositions. However, there is a lack of well-proven theory that can explain the salinity of the order of 5000 μS/cm in the deeper aquifers of Delhi. This work identifies inconclusiveness in the previous theories of marine ingression, evaporation enrichment and subsequent leaching of salt. Further, the study depicts a conceptual understanding of the origin of salinity in groundwater based on the integrated investigations of groundwater quality, age and stable isotopic fingerprinting as well as GIS based mapping of geomorphic features. In order to explain the salinity observed in groundwater of NCT Delhi, a phenomenological scenario is illustrated and supported by additional evidences. The highest average EC value was for the shallow aquifer and is strongly symptomatic of anthropogenic influences on groundwater chemistry. Piper diagram showed heterogeneous water type and sufficient recharge/mixing of the groundwater from different aquifers. The relationship between Cl-/Br- ratios vs. Cl- indicated dissolution of salt deposits containing evaporative fraction present in the unsaturated zones or in the sediments of deeper aquifers and leaching of evaporative minerals from dunes of the adjacent Thar Desert. Cl-/SO42- ratio suggested the presence of connate seawater, halite dissolution and concentration of dissolved salts by evapo-transpiration of river water diverted for irrigation. The results show, that the closed inland marine conditions developed and buried with the active sedimentation in the geological past in this region, and further intensive

  8. Hydrogeochemical response of groundwater springs during central Italy earthquakes (24 August 2016 and 26-30 October 2016)

    Science.gov (United States)

    Archer, Claire; Binda, Gilberto; Terrana, Silvia; Gambillara, Roberto; Michetti, Alessandro; Noble, Paula; Petitta, Marco; Rosen, Michael; Pozzi, Andrea; Bellezza, Paolo; Brunamonte, Fabio

    2017-04-01

    Co-seismic hydrological and chemical response at groundwater springs following strong earthquakes is a significant concern in the Apennines, a region in central Italy characterized by regional karstic groundwater systems interacting with active normal faults capable of producing Mw 6.5 to 7.0 seismic events. These aquifers also provide water supply to major metropolitan areas in the region. On August 24, 2016, a Mw 6.0 earthquake hit Central Italy in the area where Latium joins Umbria, Marche and Abruzzi; this was immediately followed one hour later by a Mw 5.4 shock. The epicenter of the event was located at the segment boundary between the Mt. Vettore and Mt. Laga faults. On October 26, 2016 and on October 30, 2016, three other big shocks (Mw 5.5, Mw 6.0 and Mw 6.5) ruptured again the Vettore Fault and its NW extension. Immediately after Aug. 24, we sampled springs discharging different aquifers in the Rieti area, including the Peschiera spring, which feeds the aqueduct of Rome. Thermal springs connected with deep groundwater flowpaths were also sampled. These springs, sampled previously in 2014 and 2015, provide some pre-earthquake data. Moreover, we sampled 4 springs along the Mt. Vettore fault system: 3 small springs at Forca di Presta, close to the trace of the earthquake surface ruptures, and two in Castel Sant'Angelo sul Nera. The latter are feeding the Nera aqueduct and the Nerea S.p.A. mineral water plant, which also kindly allowed us to collect bottled water samples from the pre-seismic period. The aim of this study is to evaluate the strong earthquake sequence effects on the hydrochemistry and flow paths of groundwater from different aquifer settings based on analysis before and after seismic events. The comparison between the responses of springs ca. 40 km from the epicenter (Rieti basin) and the springs located near the epicenter (Castelsantangelo sul Nera and Forca di Presta) is especially significant for understanding the resilience of groundwater

  9. NURE hydrogeochemical and stream sediment data release for pilot study samples from portions of the Sterling and Greeley NTMS Quadrangles, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, H.P.

    1978-10-01

    During four distinct time periods between December 1976 and August 1977, students collected samples from the two areas. One purpose was to determine the effect of seasonal variations upon the elemental concentrations, particularly uranium.

  10. Contamination of waterlands by underground weirs Hydrogeochemical and hydrodynamic processes. Contaminacion de acuiferos a partir de vertederos enterrados: procesos hidrogeoquimicos e hidrodinamicos

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, A.; Font, X. (Barcelona Univ. (Spain). Facultad de Geologia)

    1993-02-01

    The present study deals with the evolution of the contamination in the central area of the pan of La Llagosta (basin of the River Besos, Barcelona); whose waterland has, up till now, been supplying numerous towns and industries and which is, at present, affected by the contamination processes due to the presence of heavy metals and organic microcontaminants. the present analysis has been effected through the application of a mathematical model for the solute flow and hydrochemical speciation models using the data from diverse sampling campaigns and the tapping sites which the Sociedad de Aguas de Barcelona has in that area. (Author)

  11. Multielement chemical and statistical analyses from a uranium hydrogeochemical and stream-sediment survey in and near the Elkhorn Mountains, Jefferson County, Montana; Part II, Stream sediments

    Science.gov (United States)

    Suits, V.J.; Wenrich, K.J.

    1982-01-01

    Fifty-two stream-sediment samples, collected from an area south of Helena, Jefferson County, Montana, were sieved into two size fractions (50 ppm for the fine fraction) were encountered in samples from the Warm Springs Creek drainage area, along Prickly Pear Creek near Welmer and Golconda Creeks and along Muskrat Creek. All groups showed a significant correlation at the 99 percent confidence level (r between 0.73 and 0.77) between U and Th. Uranium was found to correlate significantly only with Th (as mentioned above) and with -Ni in the fine fraction of the volcanics group. U correlates significantly with -Al2O3, Ba, organic C, -K2O, -Sr and Y in both size fractions for the Boulder batholith. Correlations between U and each of several elements differ for the fine and coarse fractions of the Boulder batholith group, suggesting that the U distribution in these stream sediments is in large part controlled by grain size. Correlations were found between U and CaO, Cr, Fe203, -Na2O, Sc, -SiO2, TiO2, Yb and Zr in the coarse fraction but not in the fine fraction. U correlates weakly (to the 90% confidence level, crc<.37) with -Co and -Cu in the fine but not the coarse fraction. These results are compared to a previous study in the northern Absaroka mountains. Correlation coefficients between all other elements determined from these samples are also shown in Tables 12 to 15.

  12. Hydrogeochemical Investigation of Recharge Pathways to Intermediate and Regional Groundwater in Canon de Valle and Technical Area 16, Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Brendan W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-14

    In aquifers consisting of fractured or porous igneous rocks, as well as conglomerate and sandstone products of volcanic formations, silicate minerals actively dissolve and precipitate (Eby, 2004; Eriksson, 1985; Drever, 1982). Dissolution of hydrated volcanic glass is also known to influence the character of groundwater to which it is exposed (White et al., 1980). Hydrochemical evolution, within saturated zones of volcanic formations, is modeled here as a means to resolve the sources feeding a perched groundwater zone. By observation of solute mass balances in groundwater, together with rock chemistry, this study characterizes the chemical weathering processes active along recharge pathways in a mountain front system. Inverse mass balance modeling, which accounts for mass fluxes between solid phases and solution, is used to contrive sets of quantitative reactions that explain chemical variability of water between sampling points. Model results are used, together with chloride mass balance estimation, to evaluate subsurface mixing scenarios generated by further modeling. Final model simulations estimate contributions of mountain block and local recharge to various contaminated zones.

  13. Multivariate statistical analysis and hydrogeochemical modelling of seawater-freshwater mixing along selected flow paths: Case of Korba coastal aquifer Tunisia

    Science.gov (United States)

    Slama, Fairouz; Bouhlila, Rachida

    2017-11-01

    Groundwater sampling and piezometric measurements were carried out along two flow paths (corresponding to two transects) in Korba coastal plain (Northeast of Tunisia). The study aims to identify hydrochemical processes occurring when seawater and freshwater mix. Those processes can be used as indicators of seawater intrusion progression and freshwater flushing into seawater accompanying Submarine Groundwater Discharge (SGD). Seawater fractions in the groundwater were calculated using the chloride concentration. Hierarchical cluster analysis (HCA) was applied to isolate wells potentially affected by seawater. In addition, PHREEQC was used to simulate the theoretical mixing between two end members: seawater and a fresh-brackish groundwater sample. Geochemical conventional diagrams showed that the groundwater chemistry is explained by a mixing process between two end members. Results also revealed the presence of other geochemical processes, correlated to the hydrodynamic flow paths. Direct cation exchange was linked to seawater intrusion, and reverse cation exchange was associated to the freshwater flushing into seawater. The presence of these processes indicated that seawater intrusion was in progress. An excess of Ca, that could not be explained by only cation exchange processes, was observed in both transects. Dedolomitization combined to gypsum leaching is the possible explanation of the groundwater Ca enrichment. Finally, redox processes were also found to contribute to the groundwater composition along flow paths.

  14. Tracing groundwater salinization processes in coastal aquifers: a hydrogeochemical and isotopic approach in the Na-Cl brackish waters of northwestern Sardinia, Italy

    Directory of Open Access Journals (Sweden)

    G. Mongelli

    2013-07-01

    conclusion that they are meteoric in origin. A significant consequence of the meteoric origin of the Na-Cl-type water studied here is that the Br / Cl ratio, extensively used to assess the origin of salinity in fresh water, should be used with care in carbonate aquifers that are near the coast. Overall, δ34S and δ18O levels in dissolved SO4 suggest that water–rock interaction is responsible for the Na-Cl brackish composition of the water hosted by the Jurassic and Triassic aquifers of the Nurra, and this is consistent with the geology and lithological features of the study area. Evaporite dissolution may also explain the high Cl content, as halite was detected within the gypsum deposits. Finally, these Na-Cl brackish waters are undersaturated with respect to the more soluble salts, implying that in a climate evolving toward semi-arid conditions, the salinization process could intensify dramatically in the near future.

  15. Uranium Hydrogeochemical and Stream Sediment Reconnaissance data from the area of the Teller, Bendeleben, Candle, and Kateel River Quadrangles, Seward Peninsula and vicinity, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, R.R. Jr.; Hill, D.E.

    1978-05-01

    During July-August 1976, 2026 natural waters and 2085 bottom sediments were collected from 2209 sample locations (at a nominal density of one location each 23 km/sup 2/) on streams and small lakes throughout the Teller, Bendeleben, Candle, and western one-third of the Kateel River NTMS quadrangles, Alaska. Total uranium was measured in the waters by fluorometry and in the sediments and a few waters by delayed-neutron counting. The uranium content of the waters ranged from below the detection limit of 0.02 parts per billion (ppB) to a high of 14.50 ppB, averaging 0.44 ppB, and that of the sediments ranged from a low of 0.2 parts per million (ppM) to a high of 107.4 ppM, averaing 3.93 ppM. The uranium data for water and sediment are separately presented--as computer listings that include pertinent field measurements from each location, as graphically portrayed concentration overlays at 1:250,000 scale for each quadrangle, and as reduced figures showing contours drawn at various concentration levels for each quadrangle--and their areal distributions are compared and correlated with the known features and uranium showings. A test of increasingly detailed methods of data evaluation shows that the more extensive the evaluation, the more useful the reconnaissance uranium data are likely to be. The validity and potential usefulness of the HSSR uranium data are conclusively substantiated by the fact that evidence of all 23 of the reported uranium showings in the 50,000-km/sup 2/ study area can be discerned. Several new locations of interest for further field investigation are identified in each of the quadrangles, and most notably in the Bendeleben Mountains. However, the data presented would appear equally useful in guiding field investigation around the uranium occurrences already known, as noteworthy samples often come from close by but on tributary drainages adjacent, opposite, or above them.

  16. hydrogeochemical assessment of groundwater in kaltungo and ...

    African Journals Online (AJOL)

    Admin

    anthropogenic activities and geology on the groundwater quality of ... A. Abdulhakeem Department of Geology,Federal University of Technology, Yola, Nigeria. ...... io n c u rv e s o. f s o m e c h e m ic a. l p a ra m e te rs in th e s tu d y a re a . R. 2. = 0.989. C a. + m g. (m g. /l). 1. 7. 5. 1. 5. 0. 1. 2. 5. 1. 0. 0. 7. 5. 1. 7. 5. 1. 5. 0. 1.

  17. Hydrogeochemical evolution and potability evaluation of saline ...

    Indian Academy of Sciences (India)

    for future management and monitoring strategies as well as policy making decisions. As a part of this groundwater resource assessment, the present article reports a comprehensive assessment of the alluvial aquifers of Rajnagar block from a water potability perspective, with respect to domestic, irrigation and industrial use.

  18. Hydrogeochemical analysis and evaluation of groundwater quality ...

    Indian Academy of Sciences (India)

    leaching of secondary salts and anthropogenic impact by industry and salt water intrusion. Spatial distribution of EC indicates anthropogenic .... trial estate SIPCOT (Small Industries Promotion. Corporation of Tamil Nadu) with groups of .... saline nature in the groundwater. In SUM and SWM, cluster of samples fell in Na–Cl ...

  19. Groundwater circulation and hydrogeochemical evolution in ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 126; Issue 2. Groundwater circulation ... Deuterium and oxygen-18 isotopes in groundwater samples indicate that the recharge of groundwater is happened by meteoric water andglacier melt-water in the Kunlun Mountains, and in three different recharge conditions.

  20. Hydrogeochemical analysis and evaluation of groundwater quality ...

    Indian Academy of Sciences (India)

    Water samples were collected from different formations of Gadilam river basin and analyzed to assess the major ion chemistry and suitability of water for domestic and drinking purposes. Chemical parameters of groundwater such as pH, electrical conductivity (EC), total dissolved solids (TDS), Sodium (Na+), Potassium (K+), ...

  1. Techniques to develop data for hydrogeochemical models

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, C.M.; Holcombe, L.J.; Gancarz, D.H.; Behl, A.E. (Radian Corp., Austin, TX (USA)); Erickson, J.R.; Star, I.; Waddell, R.K. (Geotrans, Inc., Boulder, CO (USA)); Fruchter, J.S. (Battelle Pacific Northwest Lab., Richland, WA (USA))

    1989-12-01

    The utility industry, through its research and development organization, the Electric Power Research Institute (EPRI), is developing the capability to evaluate potential migration of waste constitutents from utility disposal sites to the environment. These investigations have developed computer programs to predict leaching, transport, attenuation, and fate of inorganic chemicals. To predict solute transport at a site, the computer programs require data concerning the physical and chemical conditions that affect solute transport at the site. This manual provides a comprehensive view of the data requirements for computer programs that predict the fate of dissolved materials in the subsurface environment and describes techniques to measure or estimate these data. In this manual, basic concepts are described first and individual properties and their associated measurement or estimation techniques are described later. The first three sections review hydrologic and geochemical concepts, discuss data requirements for geohydrochemical computer programs, and describe the types of information the programs produce. The remaining sections define and/or describe the properties of interest for geohydrochemical modeling and summarize available technique to measure or estimate values for these properties. A glossary of terms associated with geohydrochemical modeling and an index are provided at the end of this manual. 318 refs., 9 figs., 66 tabs.

  2. Hydrogeochemical and isotopic characterization of the groundwater ...

    African Journals Online (AJOL)

    POSTE7

    The climate fluctuates between semi-arid and arid. The rainfall in this region is very irregular and ... and locally communicate freely with the semi-Quaternary through leakages. The shallow groundwater of the ...... L'évaporation des nappes phréatiques sous climat aride est-elle indépendante de la nature du sol ? C.R. Acad.

  3. Hydrogeochemical assessment of groundwater in Kaltungo and ...

    African Journals Online (AJOL)

    Analytical results indicate that groundwater samples from kaltungo and environs are polluted due to high concentrations of iron, fluoride, nitrate, and coliform bacteria. Iron concentrations ... mg/l to 163.7 mg/l. Piper trilinear plots classified the water into Ca-(Mg)-HCO3 which belongs to the normal alkaline fresh water type.

  4. Hydrochemical assessment of freshening saline groundwater using multiple end-members mixing modeling: A study of Red River delta aquifer, Vietnam

    Science.gov (United States)

    Kim, Ji-Hyun; Kim, Kyoung-Ho; Thao, Nguyen Thi; Batsaikhan, Bayartungalag; Yun, Seong-Taek

    2017-06-01

    In this study, we evaluated the water quality status (especially, salinity problems) and hydrogeochemical processes of an alluvial aquifer in a floodplain of the Red River delta, Vietnam, based on the hydrochemical and isotopic data of groundwater samples (n = 23) from the Kien Xuong district of the Thai Binh province. Following the historical inundation by paleo-seawater during coastal progradation, the aquifer has been undergone progressive freshening and land reclamation to enable settlements and farming. The hydrochemical data of water samples showed a broad hydrochemical change, from Na-Cl through Na-HCO3 to Ca-HCO3 types, suggesting that groundwater was overall evolved through the freshening process accompanying cation exchange. The principal component analysis (PCA) of the hydrochemical data indicates the occurrence of three major hydrogeochemical processes occurring in an aquifer, namely: 1) progressive freshening of remaining paleo-seawater, 2) water-rock interaction (i.e., dissolution of silicates), and 3) redox process including sulfate reduction, as indicated by heavy sulfur and oxygen isotope compositions of sulfate. To quantitatively assess the hydrogeochemical processes, the end-member mixing analysis (EMMA) and the forward mixing modeling using PHREEQC code were conducted. The EMMA results show that the hydrochemical model with the two-dimensional mixing space composed of PC 1 and PC 2 best explains the mixing in the study area; therefore, we consider that the groundwater chemistry mainly evolved by mixing among three end-members (i.e., paleo-seawater, infiltrating rain, and the K-rich groundwater). The distinct depletion of sulfate in groundwater, likely due to bacterial sulfate reduction, can also be explained by EMMA. The evaluation of mass balances using geochemical modeling supports the explanation that the freshening process accompanying direct cation exchange occurs through mixing among three end-members involving the K-rich groundwater. This

  5. GROUND WATER ASSESSMENT IN AGRICULTURAL AREA, CASE STUDY FROM MACHANG-MALAYSIA (Penilaian Air Tanah di Daerah Pertanian, Studi Kasus di Machang Malaysia

    Directory of Open Access Journals (Sweden)

    Nur Islami

    2010-11-01

    Full Text Available ABSTRACT The study area is located in Machang, North Kelantan - Malaysia. The North Kelantan plain is covered with Quaternary sediments overlying granite bedrock. The drainage system is dendritic with the main river flowing into the South China Sea. Hydrogeochemical method was used to study groundwater of shallow aquifer characters within the area. Based on water samples analysis collected from the study area, it can be deduced that the cations and anions concentration are good for domestic use except in the southern region which the nitrate concentration is higher (more than 20 mg/l compared to the northern region (relatively zero. The areas that possibly possess nitrate-contaminated groundwater have been mapped along with groundwater flow patterns. The southern and middle part of the study area has an east to west groundwater flow pattern, making it impossible for contaminated water from the southern region to enter the northern area, despite in the northern area has lower elevation. ABSTRAK Lokasi area studi adalah berada di Machang, Kelantan Utara – Malaysia. Dataran tanah wilayah Kelantan Utara dilapisi oleh batuan Sedimen Kuarter yang mana batuan granit sebagai batuan dasar. Sistem pengairan adalah berbentuk jaringan dendritik dengan sungai utama mengalir ke Laut Cina Selatan. Metoda hydrogeochemical digunakan untuk mempelajari karakter air tanah dari akuifer dangkal untuk keseluruhan area studi. Berdasarkan pada analisa air yang diperoleh dari area studi, dapat disimpulkan bahwa konsentrasi kation dan anion baik digunakan untuk kehidupan sehari hari kecuali air tanah di area sebelah selatan yang mana kandungan nitratnya tinggi (lebih dari 20 mg/l dibandingkan di area sebelah utara (hampir tidak ada kandungan nitrat. Area yang memungkinkan memiliki konsentrasi nitrat pada air tanah dipetakan dengan kombinasi pola aliran air tanah. Pola aliran air tanah di area belahan selatan dan bagian tengah adalah dari timur ke barat yang mana tidak

  6. A preliminary study on the geochemical environment for deep geological disposal of high level radioactive waste in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Koh, Yong Kwon; Park, Byoung Yun

    2000-03-01

    Geochemical study on the groundwater from crystalline rocks (granite and gneiss) for the deep geological disposal of high-level radioactive waste was carried out in order to elucidate the hydrogeochemical and isotope characteristics and geochemical evolution of the groundwater. Study areas are Jungwon, Chojeong, Youngcheon and Yusung for granite region, Cheongyang for gneiss region, and Yeosu for volcanic region. Groundwaters of each study areas weree sampled and analysed systematically. Groundwaters can be grouped by their chemistry and host rock. Origin of the groundwater was proposed by isotope ({sup 18}O, {sup 2}H, {sup 13}C, {sup 34}S, {sup 87}Sr, {sup 15}N) studies and the age of groundwater was inferred from their tritium contents. Based ont the geochemical and isotope characteristics, the geochemical evolutions of each types of groundwater were simulated using SOLVEQ/CHILLER and PHREEQC programs.

  7. Studies of the mobility of uranium and thorium in Nevada Test Site tuff

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, H.A.; Flexser, S.; Smith, A.R. [Lawrence Berkeley Lab., CA (United States)

    1991-06-01

    Hydro-geochemical processes must be understood if the movement of radionuclides away from a breached radioactive waste canister is to be modeled and predicted. In this respect, occurrences of uranium and thorium in hydrothermal systems are under investigation in tuff and in rhyolitic tuff that was heated to simulate the effects of introduction of radioactive waste. In these studies, high-resolution gamma spectrometry and fission-track radiography are coupled with observations of alteration mineralogy and thermal history to deduce the evidence of, or potential for movement of, U and Th in response to the thermal environment. Observations to date suggest that U was mobile in the vicinity of the heater but that localized reducing environments provided by Fe-Ti-Mn-oxide minerals concentrated U and thus attenuated its migration.

  8. Freshwater lenses as ecological and population sustenance, case study in the coastal wetland of Samborombón Bay (Argentina).

    Science.gov (United States)

    Tanjal, Carolina; Carol, Eleonora; Richiano, Sebastián; Santucci, Lucía

    2017-09-15

    Freshwater lenses associated to shell ridges and sand sheets exist on the coastal wetland of Samborombón Bay. As they constitute one of the most vulnerable aquifer systems, it is the aim of this study to determine the hydrogeochemical processes that condition the chemical quality of its groundwater and to assess their present and future capability as sustenance of native woods and local villagers. To achieve this, hydrogeomorphological field surveys were made and groundwater samples were taken. Results show that lenses have a mean thickness of 12m and its chemical quality depends on the dissolution of CO 2(g) and carbonates, weathering of silicates and ion exchange. Lenses can be affected by long-term climatic variability and mining. The study of morphology and geochemistry of the freshwater lenses bring lights into important information about the management of water resources and conservation of the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Batch and column studies of adsorption of Li, Ni and Br by a reference sand for contaminant transport experiments

    Energy Technology Data Exchange (ETDEWEB)

    Seigel, M.D. [Sandia National Labs., Albuquerque, NM (United States); Ward, D.B.; Bryan, C.R. [Univ. of New Mexico, Albuquerque, NM (United States)] [and others

    1995-09-01

    A processed quartz sand (Wedron 510), mined from the St. Peter sandstone, has been characterized by a variety of chemical and physical methods for use as a reference porous media in transport model validation experiments. Wedron 510 sand was used in an intermediate-scale experiment involving migration of Ni, Li and Br through a 6-m high x 3-m diameter caisson. Ni and Li adsorption/desorption, and Li/Ni site-competition experiments yielded information on the importance of the trace mineral phases to adsorption of Li and Ni by the sand. The presence of an iron hydroxide coating similar to goethite on the sand grains is suggested by visual observation and leaching experiments. Kaolinite was identified by SEM and XRD as a significant trace mineral phase in the sand and occurs as small particles coating the sand grains. Quartz, the predominant constituent of the sand by weight, does not appear to contribute significantly to the adsorption properties of the sand. Qualitatively, the adsorption properties of the sand can be adequately modeled as a two-mineral system (goethite and kaolinite). The studies described in this report should provide a basis for understanding transport of Ni, Li and Br through porous media similar to the reference sand. Techniques were developed for obtaining parameter values for surface complexation and kinetic adsorption models for the sand and its mineral components. These constants can be used directly in coupled hydrogeochemical transport codes. The techniques should be useful for characterization of other natural materials and elements in high-level nuclear waste in support of coupled hydrogeochemical transport calculations for Yucca Mountain.

  10. Geo-Electric and Hydrogeochemical Mapping of Quaternary ...

    African Journals Online (AJOL)

    Michael Horsfall

    Depth to water level ranges from 3.5m to 5.5m. Ground water flow is from northeast to southwest towards the Warri River. Ground water which is used here for domestic purposes without treatment is soft and it is shown that the most important factor contributing to groundwater chemistry is weathering of the aquifer matrix.

  11. Hydrogeochemical and anthropogenic influence on the quality of ...

    African Journals Online (AJOL)

    REGINA

    2013-11-14

    Nov 14, 2013 ... chemical quality of groundwater is controlled by natural processes such as precipitation, mineral weathering and evaporation-crystallisation and also significantly influenced by anthropogenic processes (Lerner and. Barrett, 1996). Variation in levels of water constituents. (major ions) may be attributed to the ...

  12. Hydrogeochemical and anthropogenic influence on the quality of ...

    African Journals Online (AJOL)

    REGINA

    2013-11-14

    Nov 14, 2013 ... Key words: Groundwater chemistry, microbial quality, anthropogenic influence, Rio del Rey Basin. ... traced to the use of water from shallow, unprotected ...... Low salinity water. (SAR < 6) can also be used for irrigation on most soils with little danger of developing harmful levels of exchangeable sodium ...

  13. Investigation of Hydro-Geochemical Characteristics of Groundwater ...

    African Journals Online (AJOL)

    Michael Horsfall

    presence of multiple aquifers. The need to ascertain the quality of water used by humans has become very intense in the past decade. (Olatunji, et al., 2005; Nwankwoala et al., 2007). It has also been established that geology has a role to play in the chemistry of subsurface water (Abimbola, et al., 2002; Olatunji, et al., 2001) ...

  14. Hydrogeochemical characteristics of the River Sava watershed in Slovenia

    Directory of Open Access Journals (Sweden)

    Tjaša Kanduč

    2007-06-01

    Full Text Available The River Sava is a typical HCO3- – Ca2+ – Mg2+ River. Total alkalinity increases in the part of the watershed composed of carbonate and clastic rocks, which are less resistant to weathering processes. Ca2+/Mg2+ ratios are around 2 in the carbonate part of the watershed and increase in the watershed composed of carbonate and clastic rocks, indicating dissolution of calcite with magnesium. According to PHREEQC for Windows calculations, the River Sava and its tributaries are oversaturated with respect to calcite and dolomite. δ18OH2O and δDH2O are related to the meteorological patterns in the drainage basin. River water temperatures fluctuate annually following air temperatures.The relationship between the temperature and δ18OH2O and δDH2O values primarily reflects the strong dependenceof δ18O and δD on precipitation and evaporative enrichment in heavy oxygen and hydrogen isotopes of infiltrating water recharging the River Sava from its slopes.The δ13CDIC values are controlled by processes in the terrestrial ecosystem and stream proces-ses such as: (1 dissolution of carbonates, (2 soil derived CO2, and (3 equilibration with atmospheric CO2. Lower δ13CDIC values are observed in the spring sampling season due to abundant precipitation related to soil leaching of CO2 in the river system. From discharge and concentration measurements of sulphate and according to the drainage area of the River Sava basin, the annual sulphur fluxat the border with Croatia was estimated to be 1.4 × 107 g SO4/km2. Assuming that the sources of SO42- to the Sava are its tributaries, precipitationand other sources, the contributions of these inputs were calculated according to steady state equations and estimated to be 52 : 8 : 40 %, respectively. Other sources are attributed to human influences such as industrial pollution and oxidation of sulphides.

  15. hydrogeochemical appraisal of fluoride in groundwater of langtang ...

    African Journals Online (AJOL)

    DIBAL

    samples (rock and water) show that four major rock units make up the geology of the area; coarse porphyritic biotite granite, migmatite ... INTRODUCTION. In most rural communities in northern Nigeria, the supply of water for drinking and other purposes is solely from surface (ponds, streams and rivers) and groundwater.

  16. Geophysical and hydrogeochemical evaluation of a spring In Ado ...

    African Journals Online (AJOL)

    The ER utilized pole-pole and Schlumberger electrode arrays for profiling and Vertical Electrical Soundings (VES) respectively. A hand-dug well was sited at higher elevation and ten meters away from the spring. Microbial and physicochemical analyses were conducted on water samples from the spring and the well.

  17. Geo-Electric and Hydrogeochemical Mapping of Quaternary ...

    African Journals Online (AJOL)

    SO4 2-> Cl- for the anions; trends that are not only a departure from normal pristine conditions, but also basically different from those observed in nearby Warri and indicative of possible contamination. The relatively low calcium and magnesium content is identified as a potential health problem if water constitutes the main ...

  18. Geochemistry and hydrogeochemical process of groundwater in the ...

    African Journals Online (AJOL)

    Ground water is the only hydrous resource exploited in the Souf valley of Algerian Sahara. Several techniques and conventional graphical plots were used to define the geochemistry of the aquifer. Based on the ionic components, hydrochemical facies, the factors controlling groundwater chemistry are assessed and defined ...

  19. 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.

  20. Geological Geophysical and structural studies in Mina Ratones (Pluton de Albala); Estudios geologico-estructurales y geofisicos en Mina Ratones (Pluton de Albala)

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Estaun, A.; Carbonell, R.; Marti, D.; Flecha, I. [Instituto de Ciencias de la Tierra Jaume Almera. Barcelona (Spain); Escuder Viruete, J. [Universidad complutense de Madrid. Madrid (Spain)

    2002-07-01

    Mina Ratones environmental restoration project included petrological, structural,geophysical, hydrogeological and hydrogeochemical studies. The main objective of the geologic-structural and geophysical studies was the Albala granite structural characterization around the Mina Ratones uranium mine. The location of facies, fault zones (faults and dykes) as well as the distribution of some physical properties inside the rock massif was obtained for a granitic black of 900, 500, and 500 m. The geologic-structural and geophysical techniques applied to Mina Ratones provided a multidisciplinary approach for high resolution characterization of rock massif, and the structures potentially containing fluids,able to be applied to the hydrogeological modelling to a particular area. Geological studies included a detailed structural mapping of the area surrounding the mine (1:5,000 scale), the geometric, kinematics, and dynamics analysis of fractures of all scales, the petrology and geochemistry of fault rocks and altered areas surrounding fractures, and the microstructural studies of samples from surface and core lags. The construction of geostatistical models in two and three dimensions had helped to characterize the Mina Ratones rock massif showing the spatial distribution of fault zones, fracture intensity, granite composition heterogeneities, fluid-rock interaction zones, and physical properties. (Author)

  1. Contamination of fluoride in groundwater and its effect on human health: a case study in hard rock aquifers of Siddipet, Telangana State, India

    Science.gov (United States)

    Narsimha, A.; Sudarshan, V.

    2017-09-01

    Hydrogeochemical investigation has been carried out in the granitic terrain of Siddipet area, Medak district, Telangana State, India with an aim to understand the distribution of fluoride in the groundwater and to understand the relationship of fluoride with other major ions, and also to identify the high fluoride-bearing groundwater zones. 104 groundwater samples were analyzed in the study area for fluoride and other major ions like calcium, magnesium, chloride, carbonate, bicarbonate, sodium, potassium, sulfate, and nitrate in addition to pH and electrical conductivity. The studies revealed that the concentration of fluoride in groundwater is ranging from 0.2 to 2.2 mg L-1 with a mean of 1.1 mg L-1. Nearly 22 % of groundwater has more than the permissible limit of fluoride (1.5 mg L-1), which is responsible for the endemic dental fluorosis in the area concerned. Geochemical classification of groundwater shows that Na-HCO3, Ca-Cl, and Ca-HCO3-Na are the dominant hydrochemical facies. Gibbs diagram shows rock-water interaction dominance and evaporation dominance, which are responsible for the change in the quality of water in the hard rock aquifer of the study area. The groundwater in villages and its environs are affected by fluoride contamination, and consequently majority of the population living in these villages suffer from dental fluorosis. Hence, they are advised to consume drinking water which has less than 1.5 mg L-1 fluoride to avoid further fluorosis risks.

  2. Geological and ecological assessment of the exposure degree of the Zăton-Bulba karst system (Mehedinţi Plateau to anthropogenic hazards: intrinsic vulnerability and biodiversity study

    Directory of Open Access Journals (Sweden)

    Cristian Goran

    2010-01-01

    Full Text Available The Mehedinţi Plateau represents an area highly marked by the intensity of the karst processes and by the diversity of the exokarst and endokarst features. The analyzed area includes two parallel limestone bars, developed on the Carpathian structures direction (NNE-SSW. The geological and geomorphological research, guided by a working protocol similar to that of the EPIK method, highlighted the role played by the lithology, structure, tectonics, epikarst and protective cover, related to the infiltration conditions, flow parameters and impact area of a potential contamination event; also, we carried on microtectonic studies on the Bulba Valley, Peşterii Hill, Podul Natural Cave and Bulba Cave. In addition to the results obtained following the EPIK method protocol, we bring forward data concerning the water quality, performing hydrogeochemical analyses on water samples collected from the main sources in the region. Our research has been focused on TDS, on cations (Ca2+, Mg2+, Na+, K+, NH4+ and on anions (HCO3-, Cl-. We conclude by modelling the cumulative abundance and the species richness of the harvestmen (Opiliones in the studied area, under different degrees of human impact on habitats

  3. Study

    Directory of Open Access Journals (Sweden)

    Erum Zahir

    2017-05-01

    Full Text Available Physicochemical properties like density, viscosity, boiling point, saponification value (SV, iodine value (IV,and peroxide value (PV of Corn and Mustard oils were studied to evaluate the compositional quality of oils and also to investigate the effect on the use of same oil for repeated frying as it ultimately changes the physicochemical, nutritional and sensory properties of the oil. FT-IR spectroscopy was used to evaluate the degree of oxidation after heating and frying processes. Results revealed that due to the temperature change in the oil there is a notable difference in the spectral band which showed that the proportions of the fatty acids were changed. The spectra of Corn oil at the boiling point and at multiple frying times with a piece of potato showed frequencies in range of 2852.7–2926.0 cm−1 while in Mustard oil an additional peak was observed at 3633.8 cm−1 which exhibits the secondary oxidized product formation.

  4. The hydrogeochemical evolution of a barrier island freshwater reservoir: Conceptual understanding and identification of key processes

    Science.gov (United States)

    Seibert, Stephan; Holt, Tobias; Greskowiak, Janek; Freund, Holger; Böttcher, Michael E.; Massmann, Gudrun

    2017-04-01

    Coastal aquifers play an important role in satisfying the water demands for many people in the world. However, exposition to storm surges, climate change and extensive abstraction pose a threat to current and future use of these valuable water resources in many cases. To mitigate water quality constraints and ensure safe water supply applications, an in-depth understanding of relevant process that determine the water quality is required. We investigated two freshwater reservoirs below the barrier island Spiekeroog, Germany. The main freshwater reservoir is located at the western part of the island, ˜350 years old and has a vertical extension of ˜45m. The other investigated freshwater reservoir is located at the east of Spiekeroog, only a few decades old and has a vertical extension reactions. The expected freshening time of the main aquifer was estimated by means of the retardation formula for sharp fronts and corresponds to ˜880 years. A 1D PHREEQC simulation showed, however, that the effects of ongoing freshening on the present water quality (after ˜350 years) are negligible. Calculated decalcification rates amount to ˜4.4 mm/year which corresponds to ˜1.5 m downward movement of the decalcification front within the last 350 years. pH values ranging between 7.5-8.5 confirm that groundwater at Spiekeroog is in equilibrium with calcite and underline that calcite dissolution is an important process. With respect to the redox system, the data indicates oxygen and nitrate reduction within the first meters of the saturated zone but Mn-Oxide and Fe-Oxide reduction rates seem to be low in the aquifer based on measured dissolved Mn(2+) and Fe(2+) concentrations. The absence of dissolved Fe(2+) could be explained by the formation of iron sulfide minerals which is in agreement with observed sulfate reduction at greater depth indicated by elevated H2S concentrations and PHREEQC speciation calculations.

  5. Hydrogeochemical and stream sediment reconnaissance basic data report for Williams NTMS quadrangle, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Wagoner, J.L.

    1979-02-01

    Wet and dry sediments were collected throughout the 18,500-km/sup 2/arid-to-semiarid region and water samples at available streams, springs, and wells. Samples were collected between August 1977 and January 1978. Results of neutron activation analyses of uranium and trace elements and other field and laboratory analyses are presented in tabular hardcopy and microfiche format. The report includes six full-size overlays for use with the Williams NTMS 1:250,000 quadrangle. Sediment samples are divided into five general groups according to the source rock from which the sediment was derived. Background uranium concentrations for the quadrangle are relatively low, ranging from 1.91 to 2.40 ppM, with the highest associated with the Precambrian igneous and metamorphic complexes of the Basin and Range province. Uranium correlates best with the rare-earth elements and iron, scandium, titanium, and manganese. Known uranium occurrences are not readily identified by the stream sediment data.

  6. Hydrogeochemical and microbiological effects on fractures in the Excavation Damaged Zone (EDZ)

    Energy Technology Data Exchange (ETDEWEB)

    Laaksoharju, Marcus (Geopoint AB, Sollentuna (Sweden)); Gimeno, Maria; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Earth Science Dept., Zaragoza (Spain)); Pedersen, Karsten (Microbial Analytics, Moelnlycke (Sweden))

    2009-01-15

    Due to the disturbances associated with the excavation, construction and closure of the repository for storage of spent nuclear fuel, the saturation state of the groundwaters at repository depth with respect to several mineral phases may change and mineral precipitation/dissolution reactions may take place. In addition, changing groundwater conditions may facilitate microbial growth on fracture walls. These processes are of importance since they may influence the stability and safety of the Excavation Damaged Zone (EDZ) because precipitation and microbial growth may seal the hydraulically conductive fractures caused by the repository construction. Different processes expected to occur in the EDZ during the open repository conditions and after repository closure have been evaluated based on data from Forsmark, Laxemar and Aespoe. Geochemical modelling by using PHREEQC was applied to simulate the following cases: - increase of temperature to 50 deg C and 100 deg C to simulate the thermal effects from spent nuclear fuel; - open repository conditions simulating atmospheric conditions (equilibrium with atmospheric partial pressures of CO{sub 2}(g) and O{sub 2}(g)); - mixing with deep saline water simulating up-coning; - mixing with shallow infiltration waters simulating down-coning; - mixing with different proportions of cement dissolution porewater. The effect of variable temperatures (up to 100 deg C) on most of the above modelled processes has also been assessed. A preliminary estimation of the effect of mineral precipitation on the hydraulic conductivity of the EDZ has been carried out. For most of the modelling cases, the estimated decrease of the hydraulic conductivity in ten years is smaller than 2%. Microbial evaluation was used to identify the potential for microbial calcite and iron hydroxide formation during various repository conditions. The most important groundwater parameters for microorganisms, are pH and carbonate, ferrous iron, methane and the dissolved organic carbon (DOC) concentrations. The following cases where evaluated: - The potential for microbial iron hydroxide production will be large in all groundwater with ferrous iron. The production will be significant as soon as the oxygen concentration rises above 0.3 mg/L. This will trigger an increase in the Eh towards the range where iron oxidation is favourable (> 100 mV). The potential for microbial calcite formation production will be large in all groundwater with high concentrations of DOC and methane, irrespective of oxygen, Eh or pH. - Deep groundwater generally has less ferrous iron and DOC than intermediate and shallow groundwaters. It can, therefore, be assumed that the rate of microbial iron oxide and calcite formation will decrease, relative to the unchanged situation, except for cases where deep groundwater contains a high concentration of methane that mixes with a sulphate or oxygen rich groundwater. - Shallow groundwater generally has more ferrous iron and DOC (and less methane) than intermediate (unchanged) groundwater. It can, therefore, be assumed that the rate of microbial iron oxide and calcite formation will increase in relation to the unchanged situation. - The contamination explosives with nitrogen compounds will not influence the concentrations of ferrous iron, DOC or methane and the situation will, therefore, not change in relation to the unchanged situation. - The increase in pH from cement grouting will not have a large effect on the microorganisms. However, observations made in tunnels elsewhere where low pH cement has been injected reveal vivid microbial growth and formation of up to 5 cm thick slime layers on the tunnel walls, the slime clogged water conducting fractures. - There is no information available about the potential for microbial growth and activity at 50 deg C and 100 deg C. As a rule of thumb, biological processes double with every 10 deg C increase in temperature. Increasing temperature will then most probably speed up the bio-precipitating processes. It is important to note that the calculations included in this report correspond to a preliminary assessment of the groundwater sealing potential. More sophisticated calculations are required in order to increase the accuracy of the modelling and especially to be able to quantify the effects from microbial sealing. Some of these improvements include the incorporation of mineral dissolution reactions able to increase the concentrations of dissolved elements, the evaluation of kinetic vs. equilibrium approaches to the dissolution/precipitation reactions, the refinement of the thermodynamic description of the cement and grout constitutive phases and the inclusion of more realistic recipes for the low-pH cement, and probably, the implementation of reactive transport models of the EDZ and its surroundings.

  7. Uranium hydrogeochemical and stream sediment reconnaissance in Lincoln and Flathead Counties, northwest Montana

    Energy Technology Data Exchange (ETDEWEB)

    Aamodt, P.L.

    1977-05-01

    Between mid-May and late June 1976, 3409 water and water-transported sediment samples were collected from 1781 locations spread over an approximate 17000-km/sup 2/ area of northwestern Montana. All of the samples were analyzed for total uranium at the LASL, using standardized procedures and rigorous quality controls, the waters by fluorometry and the sediment (and those waters with greater than 10 ppb uranium) by delayed-neutron counting methods. All of the field collection, treatment, and packaging of the samples was performed following strict LASL specifications. The uranium concentrations measured in the waters range from undetectable (less than 0.2) ppb to 173.6 ppb, but average only 0.66 ppb. The low uranium concentrations in the waters of this area are thought to be due primarily to a general lack of readily soluble uranium and dilution with spring runoff. Those locations which did have abnormally high uranium were examined more closely, and follow-up field examinations are recommended in the vicinity of some of these sites. The uranium content of the sediment samples range from 0.5 ppM to 52.2 ppM and average 4.56 ppM. Sample locations with high and/or anomalous uranium values were examined with respect to the local geology, water chemistry, and other relevant factors. A distinct correlation between the high uranium in sediment and epithermal and mesothermal veins associated with nearby faults and folds is evident at several locations. Areas believed to be favorable for follow-up field investigations based on the sediment data are indicated. A correlation between high uranium in water and high uranium in sediment is evident at only a single location. The generally low uranium concentrations in water and moderate concentrations in sediment seem to indicate that most of the uranium that does exist in this area is bound up in resistant minerals.

  8. Hydrogeochemical and stream sediment reconnaissance basic data for Hutchinson NTMS Quadrangle, Kansas

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-27

    Results of a reconnaissance geochemical survey of the Hutchinson Quadrangle, Kansas are reported. Field and laboratory data are presented for 592 groundwater and 616 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the survey area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. The groundwater data indicate that the southwestern corner of the quadrangle offers some potential for uranium mineralization. Five large clusters of groundwaters with high uranium values occur here. Wells in the southwestern corner produce waters from the Permian Nippewalla Group and the overlying Kiowa Shale that often contain high concentrations of arsenic, molybdenum, selenium, and vanadium which are known to associate with uranium in sandstone deposits. The stream sediment data indicate that most of the uranium and thorium anomalies occur as placer-type concentrations associated with Quaternary deposits. There are three areas that show groups of high uranium and thorium concentrations in the stream sediments; one in the northeast in Chase, Lyon, Morris, and Wabaunsee Counties; one in Dickinson and Geary Counties; and the third, the large area west of long. 97/sup 0/ 20' W.

  9. Hydrogeochemical and stream sediment reconnaissance basic data report for Kingman NTMS Quadrangle, Arizona, California, and Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Qualheim, B.J.

    1978-07-01

    This report presents the results of the geochemical reconnaissance sampling in the Kingman 1 x 2 quadrangle of the National Topographical Map Series (NTMS). Wet and dry sediment samples were collected throughout the 18,770-km arid to semiarid area and water samples at available streams, springs, and wells. Neutron activation analysis of uranium and trace elements and other measurements made in the field and laboratory are presented in tabular hardcopy and microfiche format. The report includes five full-size overlays for use with the Kingman NTMS 1 : 250,000 quadrangle. Water sampling sites, water sample uranium concentrations, water-sample conductivity, sediment sampling sites, and sediment-sample total uranium and thorium concentrations are shown on the separate overlays. General geological and structural descriptions of the area are included and known uranium occurrences on this quadrangle are delineated. Results of the reconnaissance are briefly discussed and related to rock types in the final section of the report. The results are suggestive of uranium mineralization in only two areas: the Cerbat Mountains and near some of the western intrusives.

  10. Cross-Correlation Earthquake Precursors in the Hydrogeochemical and Geoacoustic Signals for the Kamchatka Peninsula

    CERN Document Server

    Ryabinin, G V; Polyakov, Yu S; Timashev, S F

    2012-01-01

    We propose a new type of earthquake precursor based on the analysis of correlation dynamics between geophysical signals of different nature. The precursor is found using a two-parameter cross-correlation function introduced within the framework of flicker-noise spectroscopy, a general statistical physics approach to the analysis of time series. We consider an example of cross-correlation analysis for water salinity time series, an integral characteristic of the chemical composition of groundwater, and geoacoustic emissions recorded at the G-1 borehole on the Kamchatka peninsula in the time frame from 2001 to 2003, which is characterized by a sequence of three groups of significant seismic events. We found that cross-correlation precursors took place 27, 31, and 35 days ahead of the strongest earthquakes for each group of seismic events, respectively. At the same time, precursory anomalies in the signals themselves were observed only in the geoacoustic emissions for one group of earthquakes.

  11. Origin of brine in the Kangan gasfield: isotopic and hydrogeochemical approaches

    NARCIS (Netherlands)

    Bagheri, R.; Nadri, A.; Raeisi, E.; Kazemi, G.A.; Eggenkamp, H.G.M.; Montaseri, A.

    2014-01-01

    The Kangan Permo-Triassic brine aquifer and the overlying gas reservoir in the southern Iran are located in Kangan and Dalan Formations, consisting dominantly of limestone, dolomite, and to a lesser extent, shale and anhydrite. The gasfield, 2,900 m in depth and is exploited by 36 wells, some of

  12. Hydrogeochemical Impact of CO2 Leakage from Geological Sequestration on Shallow Potable Aquifers

    DEFF Research Database (Denmark)

    Cahill, Aaron Graham

    Climate change induced by anthropogenic CO2 emissions is widely accepted to be the greatest immediate threat faced by modern civilization. Carbon capture and geological storage (CCGS) is one of the most promising geoengineering technologies currently within reach by which to, at least partially......, mitigate this threat. The capture, compression and injection of CO2 in supercritical state into deep saline aquifers is a technique which attracts criticism not least for its additional cost to energy production but more so for delaying transition to renewable energies and risks posed to the environment....... During migration CO2 would dissolve into groundwater forming carbonic acid, induce water-rock reactions and thus change groundwater chemistry. Therefore prior to implementation of this potentially necessary technology, environmental risks associated with leakage must be understood. Over the past 10 years...

  13. Uranium hydrogeochemical and stream sediment reconnaissance of the Trinidad NTMS Quadrangle, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Morris, W.A.; LaDelfe, C.M.; Weaver, T.A.

    1978-10-01

    During the field seasons of 1976 and 1977, 1,060 natural water and 1,240 waterborne sediment samples were collected from 1,768 locations in the Trinidad, Colorado, NTMS quadrangle. The samples from this 19,600-km/sup 2/ area were analyzed at the Los Alamos Scientific Laboratory for total uranium. The uranium concentrations in waters ranged from less than the detection limit of 0.02 parts per billion (ppb) to 88.3 ppb, with a mean value of 4.05 ppb. The concentrations in sediments ranged from 1.3 parts per million (ppM) to 721.9 ppM, with a mean value of 5.55 ppM. Based on simple statistical analyses of these data, arbitrary anomaly thresholds were set at 20 ppb for water samples and 12 ppM for sediment samples. By this definition, fifty-eight water and 39 sediment samples were considered anomalous. At least five areas delineated by the data appear to warrant more detailed investigations. Twenty-six anomalous water samples outline a broad area corresponding to the axis of the Apishapa uplift, seven others form a cluster in Huerfano Park, and five others outline a small area in the northern part of the San Luis Valley. Twenty-three anomalous sediment samples outline an area corresponding generally to Precambrian metamorphic rocks in the Culebra Range, and seven anomalous sediment samples form a cluster near Crestone Peak in the Sangre de Cristo Mountains.

  14. Technogenic effect of liquidation of coal mines on earth’s entrails: hydrogeochemical aspect

    Science.gov (United States)

    Tarasenko, I. A.; Zinkov, A. V.; Chudaev, O. V.; Vetoshkina, A. V.; Holodilov, I. I.

    2017-10-01

    The authors of the paper have established the geochemical features of the composition of underground waters and regularities of their formation in the areas of the liquidated coal mines of Russia and Ukraine. It is shown that the mine flood resulted in the formation of technogenic waters which geochemical specificity originates in the feeding field and is transformed in the direction of the filtration flow. It depends on the geological structure of sedimentary basins and the presence in the coal and supra-coal beds of the marine, salt-bearing and freshwater groups of geological formations. The water types are distinguished characterizing the conditions and processes of their formation that may be the regional markers in the hydrochemical and geological constructions. The technogenic waters influenced the safety of the underground waters, sources of water supply of the regions, and surface water channels. The pollutions are of local character in space.

  15. Reactive-transport modeling of fly ash-wate-brines interactions from laboratory-scale column studies

    Science.gov (United States)

    Mbugua, John M.; Catherine Ngila, J.; Kindness, Andrew; Demlie, Molla

    Dynamic leaching tests are important studies that provide more insights into time-dependent leaching mechanisms of any given solid waste. Hydrogeochemical modeling using PHREEQC was applied for column modeling of two ash recipes and brines generated from South African coal utility plants, Sasol and Eskom. The modeling results were part of a larger ash-brine study aimed at acquiring knowledge on (i) quantification and characterization of the products formed when ash is in contact with wate-brines in different scenarios, (ii) the mineralogical changes associated with wate-brine-ash interactions over time, (iii) species concentration, and (iv) leaching and transport controlling factors. The column modeling was successfully identified and quantified as important reactive mineralogical phases controlling major, minor and trace elements' release. The pH of the solution was found to be a very important controlling factor in leaching chemistry. The highest mineralogical transformation took place in the first 10 days of ash contact with either water or brines, and within 0.1 m from the column inflow. Many of the major and trace elements Ca, Mg, Na, K, Sr, S(VI), Fe, are leached easily into water systems and their concentration fronts were high at the beginning (within 0.1 m from the column inflow and within the first 10 days) upon contact with the liquid phase. However, their concentration decreased with time until a steady state was reached. Modeling results also revealed that geochemical reactions taking place during ash-wate-brine interactions does affect the porosity of the ash, whereas the leaching processes lead to increased porosity. Besides supporting experimental data, modeling results gave predictive insights on leaching of elements which may directly impact on the environment, particularly ground water. These predictions will help develop scenarios and offer potential guide for future sustainable waste management practices as a way of addressing the co

  16. Statistical study to identify the key factors governing ground water recharge in the watersheds of the arid Central Asia.

    Science.gov (United States)

    Zhu, Binq-Qi; Wang, Yue-Ling

    2016-01-01

    Understanding the source and recharge of ground waters is of great significance to our knowledge in hydrological cycles in arid environments over the world. Northern Xinjiang in northwestern China is a significant repository of information relating to the hydrological evolution and climatic changes in central Asia. In this study, two multivariate statistical techniques, hierarchical cluster analysis (HCA) and principal component analysis (PCA), were used to assess the ground water recharge and its governing factors, with the principal idea of exploring the above techniques to utilize all available hydrogeochemical variables in the quality assessment, which are not considered in the conventional techniques like Stiff and Piper diagrams. Q-mode HCA and R-mode PCA were combined to partition the water samples into seven major water clusters (C1-C7) and three principal components (PC1-PC3, PC1 salinity, PC2 hydroclimate, PC3 contaminant). The water samples C1 + C4 were classified as recharge area waters (Ca-HCO3 water), C2 + C3 as transitional zone waters (Ca-Mg-HCO3-SO4 water), and C5 + C6 + C7 as discharge area waters (Na-SO4 water). Based on the Q-mode PCA scores, three groups of geochemical processes influencing recharge regimes were identified: geogenic (i.e., caused by natural geochemical processes), geomorphoclimatic (caused by topography and climate), and anthropogenic (caused by ground water contamination). It is proposed that differences in recharge mechanism and ground water evolution, and possible bedrock composition difference, are responsible for the chemical genesis of these waters. These will continue to influence the geochemistry of the northern Xinjiang drainage system for a long time due to its steady tectonics and arid climate. This study proved that the chemistry differentiation of ground water can effectively support the identification of ground water recharge and evolution patterns.

  17. Deciphering groundwater quality for irrigation and domestic purposes - a case study in Suri I and II blocks, Birbhum District, West Bengal, India

    Science.gov (United States)

    Das, Shreya; Nag, S. K.

    2015-07-01

    Assessment of the hydrochemical characteristics of water and aquifer hydraulic properties is important for groundwater planning and management in the study area. It is not only the basic need for human existence but also a vital input for all development activities. The present hydro-geochemical study of groundwater samples from the Suri I and II blocks of Birbhum district, West Bengal (23.76 ∘-23.99 ∘N; 87.42 ∘-87.64 ∘E) was carried out to assess their suitability for agricultural, domestic and drinking purposes. For this study, samples were collected from 26 locations during the post-monsoon and pre-monsoon sessions spanning over 2012 and 2013. Groundwater samples were analyzed for their physical and chemical properties using standard laboratory methods. Physical and chemical parameters of groundwater such as pH, electrical conductivity, total dissolved solids, Na, K, Ca, Mg, Fe, Cl, HCO3, SO4 and F were determined. Various water quality indices like SAR, SSP, PI, RSC, MAR and KR have been calculated for each water sample to identify the irrigational suitability standard. According to most of these parameters, the groundwater has been found to be well to moderately suitable for irrigation. In the post-monsoon session exceptionally high RSC values for around 80% samples indicate an alkaline hazard to the soil. The ion balance histogram for post-monsoon indicates undesirable ion balance values according to fresh water standards whereas in pre-monsoon, the samples show good ion balance in water. For determination of the drinking suitability standard of groundwater, three parameters have been considered - total hardness (TH), Piper's trilinear diagram and water quality index study. Groundwater of the present study area has been found to be moderately-hard to hard during both sampling sessions and hence poses no health risk which could arise due to excess consumption of calcium or magnesium. Hydrogeochemical facies in the form of Piper's trilinear diagram plot

  18. Mechanism of groundwater inrush hazard caused by solution mining in a multilayered rock-salt-mining area: a case study in Tongbai, China

    Science.gov (United States)

    Zeng, Bin; Shi, Tingting; Chen, Zhihua; Xiang, Liu; Xiang, Shaopeng; Yang, Muyi

    2018-01-01

    The solution mining of salt mineral resources may contaminate groundwater and lead to water inrush out of the ground due to brine leakage. Through the example of a serious groundwater inrush hazard in a large salt-mining area in Tongbai County, China, this study mainly aims to analyse the source and channel of the inrushing water. The mining area has three different types of ore beds including trona (trisodium hydrogendicarbonate dihydrate, also sodium sesquicarbonate dihydrate, with the formula Na2CO3 × NaHCO3 × 2H2O, it is a non-marine evaporite mineral), glauber (sodium sulfate, it is the inorganic compound with the formula Na2SO4 as well as several related hydrates) and gypsum (a soft sulfate mineral composed of calcium sulfate dihydrate, with chemical formula CaSO4 × 2H2O). Based on characterisation of the geological and hydrogeological conditions, the hydrochemical data of the groundwater at different points and depths were used to analyse the pollution source and the pollutant component from single or mixed brine by using physical-chemical reaction principle analysis and hydrogeochemical simulation method. Finally, a possible brine leakage connecting the channel to the ground was discussed from both the geological and artificial perspectives. The results reveal that the brine from the trona mine is the major pollution source; there is a NW-SE fissure zone controlled by the geological structure that provides the main channels through which brine can flow into the aquifer around the water inrush regions, with a large number of waste gypsum exploration boreholes channelling the polluted groundwater inrush out of the ground. This research can be a valuable reference for avoiding and assessing groundwater inrush hazards in similar rock-salt-mining areas, which is advantageous for both groundwater quality protection and public health.

  19. Vadose Zone Transport Field Study: Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Andy L.; Conrad, Mark E.; Daily, William D.; Fink, James B.; Freedman, Vicky L.; Gee, Glendon W.; Hoversten, Gary M.; Keller, Jason M.; Majer, Ernest L.; Murray, Christopher J.; White, Mark D.; Yabusaki, Steven B.; Zhang, Z. F.

    2006-07-31

    migration (e.g. BC Cribs and Trenches). The improved models have been also coupled with inverse models and newly-developed parameter scaling techniques to allow estimation of field-scale and effective transport parameters for the vadose zone. The development and utility of pedotransfer functions for describing fine-scale hydrogeochemical heterogeneity and for incorporating this heterogeneity into reactive transport models was explored. An approach based on grain-size statistics appears feasible and has been used to describe heterogeneity in hydraulic properties and sorption properties, such as the cation exchange capacity and the specific surface area of Hanford sediments. This work has also led to the development of inverse modeling capabilities for time-dependent, subsurface, reactive transport with transient flow fields using an automated optimization algorithm. In addition, a number of geophysical techniques investigated for their potential to provide detailed information on the subtle changes in lithology and bedding surfaces; plume delineation, leak detection. High-resolution resistivity is now being used for detecting saline plumes at several waste sites at Hanford, including tank farms. Results from the field studies and associated analysis have appeared in more than 46 publications generated over the past 4 years. These publications include test plans and status reports, in addition to numerous technical notes and peer reviewed papers.

  20. Utilization of GIS modeling in geoenvironmental studies of Qaroun Lake, El Fayoum Depression, Egypt

    Science.gov (United States)

    Attia, Abdelaal H.; El-Sayed, Salah Abdelwahab; El-Sabagh, Moustafa E.

    2018-02-01

    Qaroun Lake, the study area, is a natural protectorate located at the northern part of El Fayoum Depression, Egypt. An integrated approach including hydrochemistry, mineralogy of sediments and GIS analysis and modeling was conducted in order to determine the different geoenvironmental parameters affecting the lake environmental system. Forty two environmental water and sediment samples were collected from the lake and relevant drains in 2013. The water samples were analyzed for major ions and trace elements and the sediment ones were analyzed for clay and non-clay minerals. This study showed that the saline water of the lake (31490 Mg2+ > Ca2+ > K+ - Cl- > SO42- > HCO3- > CO32-. The water salt assemblages were KCl - NaCl - Na2SO4 - MgSO4 - CaSO4 - Ca(HCO3)2 reflecting a mixed water type. The contents of NaCl, Na2SO4 and MgSO4 salts were found to be fully controlled with the lake depths. The hydrogeochemical investigations revealed that the evaporation concentration is the primary process of the lake water evolution. The presence of trace elements in the lake water is essentially of allochtonous origin. The GIS-based maps indicated that the concentrations of Zn, Co, Mo, Pb, F and Cd elements in water had increased in the eastern part of the lake; meanwhile, the contents of NO3- ions had increased in the southwestern part indicating that these parts were the most vulnerable to the potential pollution with such elements. The XRD analysis revealed the existence of different mineral assemblages (quartz, kaolinite, goethite, calcite, halite, hematite, feldspar, gypsum, dolomite and saponite) in bottom sediments. The mineral concentrations varied greatly from place to another place along the lake and their distributions were asymmetric. The dominant minerals were the quartz and calcite. The mineralogical compositions of sediments were highly affected by the natural and man-mad activities. The most effective processes were the type of the water and solid materials coming

  1. Groundwater fluoride enrichment in an active rift setting: Central Kenya Rift case study

    Energy Technology Data Exchange (ETDEWEB)

    Olaka, Lydia A., E-mail: lydiaolaka@gmail.com [Department of Geology, University of Nairobi, P.O Box 30197, Nairobi (Kenya); Wilke, Franziska D.H. [Geoforschungs Zentrum, Telegrafenberg, 14473 Potsdam (Germany); Olago, Daniel O.; Odada, Eric O. [Department of Geology, University of Nairobi, P.O Box 30197, Nairobi (Kenya); Mulch, Andreas [Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, 60325 Frankfurt (Germany); Institut für Geowissenschaften, Goethe Universität Frankfurt, Altenhöferallee 1, 60438 Frankfurt (Germany); Musolff, Andreas [UFZ-Helmholtz-Centre for Environmental Research, Department of Hydrogeology, Permoserstr. 15, 04318 Leipzig (Germany)

    2016-03-01

    Groundwater is used extensively in the Central Kenya Rift for domestic and agricultural demands. In these active rift settings groundwater can exhibit high fluoride levels. In order to address water security and reduce human exposure to high fluoride in drinking water, knowledge of the source and geochemical processes of enrichment are required. A study was therefore carried out within the Naivasha catchment (Kenya) to understand the genesis, enrichment and seasonal variations of fluoride in the groundwater. Rocks, rain, surface and groundwater sources were sampled for hydrogeochemical and isotopic investigations, the data was statistically and geospatially analyzed. Water sources have variable fluoride concentrations between 0.02–75 mg/L. 73% exceed the health limit (1.5 mg/L) in both dry and wet seasons. F{sup −} concentrations in rivers are lower (0.2–9.2 mg/L) than groundwater (0.09 to 43.6 mg/L) while saline lake waters have the highest concentrations (0.27–75 mg/L). The higher values are confined to elevations below 2000 masl. Oxygen (δ{sup 18}O) and hydrogen (δD) isotopic values range from − 6.2 to + 5.8‰ and − 31.3 to + 33.3‰, respectively, they are also highly variable in the rift floor where they attain maximum values. Fluoride base levels in the precursor vitreous volcanic rocks are higher (between 3750–6000 ppm) in minerals such as cordierite and muscovite while secondary minerals like illite and kaolinite have lower remnant fluoride (< 1000 ppm). Thus, geochemical F{sup −} enrichment in regional groundwater is mainly due to a) rock alteration, i.e. through long residence times and natural discharge and/or enhanced leakages of deep seated geothermal water reservoirs, b) secondary concentration fortification of natural reservoirs through evaporation, through reduced recharge and/or enhanced abstraction and c) through additional enrichment of fluoride after volcanic emissions. The findings are useful to help improve water management

  2. Groundwater of crystalline foundation of the Tatar anticline

    Energy Technology Data Exchange (ETDEWEB)

    Anisimov, B.V.; Abdullin, N.G.; Bars, Ye.A.; Doronkin, K.N.; Kaveyev, I.Kh.; Plotnikov, N.A.

    1979-01-01

    Results are presented from studying the hydrogeochemical features of the crystalline foundation of the Tatar anticline according to data of well 2000 from the Minnibayevskiy field. The expediency of further study of the collector properties and possible oil content of the Archean rocks in the marginal parts of the anticline is substantiated.

  3. Linking air and water transport in intact soils to macropore characteristics inferred from X-ray computed tomography

    DEFF Research Database (Denmark)

    Katuwal, Sheela; Nørgaard, Trine; Møldrup, Per

    2015-01-01

    Soil macropores often control fluid flow and solute transport, and quantification of macropore characteristics including their variability in space and time are essential to predict soil hydraulic and hydrogeochemical functions. In this study, measurements of air and solute transport properties a...

  4. Water quality modeling based on landscape analysis: Importance of riparian hydrology

    Science.gov (United States)

    Thomas Grabs

    2010-01-01

    Several studies in high-latitude catchments have demonstrated the importance of near-stream riparian zones as hydrogeochemical hotspots with a substantial influence on stream chemistry. An adequate representation of the spatial variability of riparian-zone processes and characteristics is the key for modeling spatiotemporal variations of stream-water quality. This...

  5. Groundwater quality and its suitability for domestic and agricultural ...

    African Journals Online (AJOL)

    Hydrogeochemical analysis of groundwater samples collected from parts of the Wilberforce Island in Bayelsa State, Southern Nigeria has been carried out in an attempt to assess the suitability of the groundwater for domestic and agricultural purposes in the area. The study was based on thirteen groundwater samples ...

  6. Interpretation of geology, geophysics and hydrochemistry for selection of geothermal drilling sites, Canon de San Diego Grant, Sandoval county, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, J.B.; McIntyre, J.R.; Klein, C.W.; Beyer, J.H.

    1978-11-01

    This project began in mid-1977 as an evaluation of the geology and hydrogeology of the Canon de San Diego Grant for Sunoco Energy Development Co. (Sunedco) and evolved late in 1977, at Sunedco's direction, into a more comprehensive study of geophysical, geologic and hydrogeochemical data. This has been used to select sites for the possible drilling of deep geothermal wells.

  7. Hydrogeochemical data for thermal and nonthermal waters and gases of the Valles Caldera- southern Jemez Mountains region, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Shevenell, L.; Goff, F.; Vuataz, F.; Trujillo, P.E. Jr.; Counce, D.; Janik, C.J.; Evans, W.

    1987-03-01

    This report presents field, chemical, gas, and isotopic data for thermal and nonthermal waters of the southern Jemez Mountains, New Mexico. This region includes all thermal and mineral waters associated with Valles Caldera and many of those located near the Nacimiento Uplift, north of San Ysidro. Waters of the region can be categorized into five general types: (1) surface and near-surface meteoric waters; (2) acid-sulfate waters at Sulphur Springs (Valles Caldera); (3) thermal meteoric waters in the ring fracture zone (Valles Caldera); (4) deep geothermal waters of the Baca geothermal field and derivative waters in the Soda Dam and Jemez Springs area (Valles Caldera); and (5) mineralized waters near San Ysidro. Some waters display chemical and isotopic characteristics intermediate between the types listed. Data in this report will help in interpreting the geothermal potential of the Jemez Mountains region and will provide background for investigating problems in hydrology, structural geology, hydrothermal alterations, and hydrothermal solution chemistry.

  8. Verification of the both hydrogeological and hydrogeochemical code results by an on-site test in granitic rocks

    Directory of Open Access Journals (Sweden)

    Michal Polák

    2007-01-01

    Full Text Available The project entitled “Methods and tools for the evaluation of the effect of engeneered barriers on distant interactions in the environment of a deep repository facility” deals with the ability to validate the behavior of applied engeneered barriers on hydrodynamic and migration parameters in the water-bearing granite environment of a radioactive waste deep repository facility. A part of the project represents a detailed mapping of the fracture network by means of geophysical and drilling surveys on the test-site (active granite quarry, construction of model objects (about 100 samples with the shape of cylinders, ridges and blocks, and the mineralogical, petrological and geochemical description of granite. All the model objects were subjected to migration and hydrodynamic tests with the use of fluorescein and NaCl as tracers. The tests were performed on samples with simple fractures, injected fractures and with an undisturbed integrity (verified by ultrasonic. The gained hydrodynamic and migration parameters of the model objects were processed with the modeling software NAPSAC and FEFLOW. During the following two years, these results and parameters will be verified (on the test-site by means of a long-term field test including the tuning of the software functionality.

  9. Hydro-geochemical evaluation of groundwater quality in Akoko North West local government area of Ondo State, Nigeria

    Directory of Open Access Journals (Sweden)

    Temitope Dare Timothy Oyedotun

    2012-04-01

    Full Text Available A sudden geometric increase in population of Akoko North West Local Government Area of Ondo State has led to an increase in demand for water and harnessing of subsurface water reserve. A total of twenty six water samples obtained from both boreholes and hand-dug wells were analyzed for their physico-chemical characteristics with the aim of assessing their quality, usability and also to determine the level of their contamination in the local government which is dominated by granite gneisses, charnockites, and augen gneisses as the main rock types. The following physico-chemical properties were analyzed for in the samples collected: electrical conductivity (EC, pH, total alkalinity (TA, total dissolved solids (TDS, total suspended solids (TSS, acid neutralizing capacity (ANC with major cations (Na+, Mg2+, Ca2+, anions (PO43-, HCO3-, SO43- and several heavy metals (Zn2+, Fe2+, As+, Ni+, Pb2+, Cd+, Cu2+. The following results were obtained from the analysis: Zn2+ (0.109 – 0.437 ppm, Fe2+ (0.216 – 0.726 ppm, As+ (0.01 – 0.03 ppm, Ni+ (0.036 – 0.074, Pb2+ (0.003 – 0.010, Cd+ (0.002 – 0.007, Cu2+ (0.086 – 0.241 with appreciable abundances of PO43-, Cd+, Fe2+and Ni+ some exceeding while some others are below the WHO acceptable level for drinking water, thereby making it a serious source of concern as it indicates varying levels of faecal contamination (from leaky septic tanks, interception with pit latrines and heavy metal liberation into the water consumed by the residents. It was also noticed that the water was fresh based on the analysis of the Total Dissolved Solids and the Pb2+ concentrations almost exceeded the standard permissible limit. Generally, it was concluded that the overall quality of the ground water is averagely good physico-chemically.

  10. Hydrogeochemical and stream sediment reconnaissance basic data for Sherman NTMS Quadrangle, Texas; Oklahoma. Uranium resource evaluation report

    Energy Technology Data Exchange (ETDEWEB)

    1978-09-29

    Field and laboratory data are presented for 718 groundwater and 715 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the survey area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. Groundwater data indicate that uranium concentrations above the 85th percentile are predominant in the Trinity Group (Lower Cretaceous), and the Taylor and Navarro Groups (Upper Cretaceous). Values of uranium above the 85th percentile also occur in the Permian units located in the northwestern section of the survey area. Several trends delineating saline water are discernable, the most notable of which occur in sections of the Woodbine Formation and the Permian units. Less distinguishing saline trends occur in many of the Upper Cretaceous formations. Stream sediment data indicate that uranium concentrations above the 85th percentile occur in sections of the Fredericksburg Group parallel to the contact with the Washita Group, in the Eagle Ford Formation, and in the Taylor Group. High values of uranium in the Fredericksburg Group appear to be associated with carbonates and marine clays. High values of uranium in the Eagle Ford Formation are most likely associated with heavy and/or resistate mineral assemblages. High values of uranium occurring in the Taylor Group may be related to the carbonate and phosphatic lithologies which comprise this group.

  11. Hydrogeochemical characterisation and evaluation of groundwater resources and review of groundwater management schemes in Kamiesberg, Northern Cape

    CSIR Research Space (South Africa)

    Van Wyk, I

    2012-01-01

    Full Text Available Kamiesberg, located in the semi-arid regions of South Africa, depends primarily on subsurface water resources for domestic, agricultural and industrial use. In order to assess geochemical evolution of groundwater and to identify salinization, a...

  12. National uranium resource evaluation program: hydrogeochemical and stream sediment reconnaissance basic data for Ely quadrangle, Nevada; Utah

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-15

    Field and laboratory data are presented for 1937 sediment samples from the Ely Quadrangle, Nevada; Utah. The samples were collected by Savannah River Laboratory; laboratory analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee.

  13. Origin of groundwater salinity and hydrogeochemical processes in a confined coastal aquifer: Case of the Rhone delta (Southern France)

    Energy Technology Data Exchange (ETDEWEB)

    Montety, Veronique de [Universite d' Avignon et des Pays de Vaucluse - INRA, UMR 1114 EMMAH, F-84000 Avignon (France)], E-mail: veronique.de-montety@univ-avignon.fr; Radakovitch, Olivier; Vallet-Coulomb, Christine [CEREGE, Aix-Marseille Universite, CNRS-CDF-IRD, Europole Mediterraneen de L' Arbois, BP 80, 13545 Aix en Provence (France); Blavoux, Bernard [Universite d' Avignon et des Pays de Vaucluse - INRA, UMR 1114 EMMAH, F-84000 Avignon (France); Hermitte, Daniel [CEREGE, Aix-Marseille Universite, CNRS-CDF-IRD, Europole Mediterraneen de L' Arbois, BP 80, 13545 Aix en Provence (France); Valles, Vincent [Universite d' Avignon et des Pays de Vaucluse - INRA, UMR 1114 EMMAH, F-84000 Avignon (France)

    2008-08-15

    The Rhone delta, South of France (Camargue, 750 km{sup 2}) is a coastal saline wetland located along the Mediterranean Sea. The confined aquifer of this delta shows high values of electrical conductivity rising from the north (4 mS/cm) to the shoreline (58 mS/cm). This work aims to identify the origin of groundwater salinity and the geochemical processes occurring in this coastal confined aquifer according to the degree of salinity. A natural tracing approach is considered using monthly sampling in 8 piezometers for chemical and isotopic analyses ({sup 18}O, {sup 2}H, {sup 13}C{sub TDIC}). Ionic and isotopic ratios demonstrate that strong salinities are due to a simple mixing between Mediterranean seawater and freshwater; seawater contribution reaches up to 98% at 8 km from the shoreline. Seawater intrusion induces a particular groundwater chemistry which varies with the degree of seawater contribution: (1) In the less saline part of the aquifer (seawater contribution <20%), the intrusion induces an increase of Na{sup +} in groundwater leading to Ca{sup 2+}/Na{sup +} exchange processes. The {delta}{sup 13}C{sub TDIC} analyses show that matrix exchange processes most likely occur for the less saline samples. (2) In the saline part of the aquifer (seawater contribution >20%), the intrusion induces SO{sub 4} reduction which is confirmed by highly depleted {delta}{sup 13}C{sub TDIC} values (up to -19 per mille ). The {delta}{sup 13}C{sub TDIC} also reveals that methanogenesis processes may occur in the most reductive part of the aquifer. Due to SO{sub 4} reduction, the intrusion induces a shift in carbonate equilibrium leading to supersaturation with respect to dolomite and/or magnesian calcite. Thus carbonate precipitation may occur in the area strongly influenced by seawater.

  14. Sulfur and oxygen isotope compositions of Upper Triassic sulfates from northern Apennines (Italy) : paleogeographic and hydrogeochemical implications

    OpenAIRE

    Boschetti, T.

    2011-01-01

    Upper Triassic bedded evaporite sulfate of the Burano Formation outcropping at Cerreto Pass between Tuscany and Emilia-Romagna in the Northern Apennines were analyzed for sulfur and oxygen isotope compositions, yielding d34S and d18O values of 15.5±0.4‰ and 10.8±1.2‰, respectively (mean ±99% confidence intervals). Combining these values with those of other Burano Formation sulfate deposits along the Apennine chain, mean for d34S and d18O values are obtained (15.2±0.2‰ and 10.9±0.5‰, respectiv...

  15. Environmental management of Aznalcóllar mine and its influence in the hydrogeochemical of the pit lake.

    Science.gov (United States)

    Santofimia, E; López-Pamo, E; Montero, E

    2013-08-01

    Since its 1995 closure and the subsequent 1998 accident, the Aznalcóllar mine pit has been used as a disposal site for diverse metal-rich materials, such as the polluted soils removed during the cleaning of areas along the Guadiamar River, waste rock, pyrite sludge, and ashes deriving from pyrite roasting. At present, the mining pit is partly flooded and contains a highly acidic (pH 2.7) pit lake with approximately 6 Mm3 of metal and sulphate-rich water. Recent detailed research performed in the area has proven that the reaction of the lake water with both the dumping mining wastes and the inflow of acid mine waters are strongly modifying the water quality of the pit lake. A major change was identified in the water quality that resulted from the dumping of 1.4 Mm3 of pyritic wastes during 2005 and 2006. The oxidative dissolution of this mineral has resulted in: (1) a total consumption of dissolved oxygen, (2) a notable increase of electric conductivity (from 8.6 to 12 mS/cm) and (3) a strong acidification (pH from 4.2 to 2.7) and an important heating that was observed as a result of the exothermic character of pyrite oxidation. Despite the total lack of oxidizing agents-such as 02 and Fe(III) (Fe[III] < 5% total Fe)-in the pit lake, pyrite is being oxidized with a continuous increase of the SO(4)2- and Fe concentrations.

  16. Uranium hydrogeochemical and stream sediment reconnaissance of the Arminto NTMS quadrangle, Wyoming, including concentrations of forty-three additional elements

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, T.L.

    1979-11-01

    During the summers of 1976 and 1977, 570 water and 1249 sediment samples were collected from 1517 locations within the 18,000-km/sup 2/ area of the Arminto NTMS quadrangle of central Wyoming. Water samples were collected from wells, springs, streams, and artifical ponds; sediment samples were collected from wet and dry streams, springs, and wet and dry ponds. All water samples were analyzed for 13 elements, including uranium, and each sediment sample was analyzed for 43 elements, including uranium and thorium. Uranium concentrations in water samples range from below the detection limit to 84.60 parts per billion (ppb) with a mean of 4.32 ppb. All water sample types except pond water samples were considered as a single population in interpreting the data. Pond water samples were excluded due to possible concentration of uranium by evaporation. Most of the water samples containing greater than 20 ppb uranium grouped into six clusters that indicate possible areas of interest for further investigation. One cluster is associated with the Pumpkin Buttes District, and two others are near the Kaycee and Mayoworth areas of uranium mineralization. The largest cluster is located on the west side of the Powder River Basin. One cluster is located in the central Big Horn Basin and another is in the Wind River Basin; both are in areas underlain by favorable host units. Uranium concentrations in sediment samples range from 0.08 parts per million (ppm) to 115.50 ppm with a mean of 3.50 ppm. Two clusters of sediment samples over 7 ppm were delineated. The first, containing the two highest-concentration samples, corresponds with the Copper Mountain District. Many of the high uranium concentrations in samples in this cluster may be due to contamination from mining or prospecting activity upstream from the sample sites. The second cluster encompasses a wide area in the Wind River Basin along the southern boundary of the quadrangle.

  17. 3DHYDROGEOCHEM: A 3-DIMENSIONAL MODEL OF DENSITY-DEPENDENT SUBSURFACE FLOW AND THERMAL MULTISPECIES-MULTICOMPONENT HYDROGEOCHEMICAL TRANSPORT

    Science.gov (United States)

    This report presents a three-dimensional finite-element numerical model designed to simulate chemical transport in subsurface systems with temperature effect taken into account. The three-dimensional model is developed to provide (1) a tool of application, with which one is able...

  18. National Uranium Resource Evaluation Program. Hydrogeochemical and stream sediment reconnaissance basic data for Manhattan NTMS Quadrangle, Kansas

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-13

    Results of a reconnaissance geochemical survey of the Manhattan Quadrangle, Kansas, are reported. Field and laboratory data are presented for 674 groundwater and 718 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the survey area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. The groundwater data indicate that the most promising area for potential uranium mineralization occurs in the western-northwestern part of the quadrangle where waters are produced from the Quaternary loess deposits, and the Cretaceous Greenhorn-Graneros and Dakota Formations. Associated elements in the quadrangle include arsenic, potassium, manganese, vanadium, and selenium. The stream sediment data indicate that the highest average uranium concentrations in sediments from the Manhattan Quadrangle are obtained from the Pennsylvanian Wabaunsee Group followed by the Cretaceous Carlile Shale, Greenhorn-Graneros and Dakota Formations. In the northwestern corner of the quadrangle, high concentrations of uranium are associated with high concentrations of barium, niobium, strontium, titanium, vanadium, yttrium, and zirconium. In southeast Cloud County and extending to the northeast, high values of total uranium are associated with high values of titanium, yttrium, zirconium, and low U-FL/U-NT values. These associations indicate that the uranium is probably present in heavy and/or resistate minerals.

  19. Incorporating the social dimension into hydrogeochemical investigations for rural development: the Bir Al-Nas approach for socio-hydrogeology

    Science.gov (United States)

    Re, Viviana

    2015-11-01

    A replicable multidisciplinary approach is presented for science-based groundwater management practices: Bir Al-Nas (Bottom-up IntegRated Approach for sustainabLe grouNdwater mAnagement in rural areaS). This approach provides a practical example of the concept of "socio-hydrogeology", a way of incorporating the social dimension into hydrogeological investigations, as reinforced by the translation of the Arabic bir al-nas: "the people's well". To achieve this, hydrogeologists act as "social hydrologists" during their monitoring activities, which often bring them into contact with local communities and end users (and polluters) of water. Not only can they retrieve reliable information about traditional know-how and local issues, but they can also change the public perception of science/scientists to create the basis for mutual collaboration and understanding in view of implementing improved integrated groundwater management. The final outcomes are expected to be an increased awareness of communities at the local level and a clear understanding of their water issues and needs from the very early stages of the investigation. Although the importance of using such methods in groundwater analysis and management is widely recognized, hydrogeological investigations are currently dominated by sectorial approaches that are easier to implement but less sustainable. The pressure of population growth, the shift towards more water-dependent economies, climate change and its impact on water availability will require scientists to use a more integrated approach, such as Bir Al-Nas, when dealing with increasing water pollution and water-scarcity issues.

  20. The continuous automatic monitoring network installed in Tuscany (Italy) since late 2002, to study earthquake precursory phenomena

    Science.gov (United States)

    Pierotti, Lisa; Cioni, Roberto

    2010-05-01

    monitoring stations. This has been carried out on the basis of: i) hydrogeologic and structural studies in order to assess the underground fluid circulation regime; ii) a detailed geochemical study of all the natural manifestations present in the selected territories, such as cold and hot springs and gas emission zones; iii) logistical aspects. Therefore, a detailed hydrogeochemical study was performed in 2002. A total of 150 water points were sampled in Garfagnana/Lunigiana area (N-W Tuscany) and analysed. Based on the results of this multidisciplinary study, five water points suitable for the installation of the monitoring stations, were selected. They are: Bagni di Lucca (Bernabò spring), Gallicano (Capriz spring) and Pieve Fosciana (Prà di Lama spring) in Garfagnana, Equi Terme (main spring feeding the swimming pool of the thermal resort) and Villafranca in Lunigiana (well feeding the public swimming pool). In the Amiata area, in the preliminary campaign, 69 water points were sampled and analyzed and five sites were selected. They are Piancastagnaio, Santa Fiora, Pian dei Renai and Bagnore, which are fed by the volcanic aquifer, and Bagno Vignoni borehole, which is fed by the evaporite carbonate aquifer. The installation and start-up process of the monitoring systems in the Garfagnana-Lunigiana area begun in November 2002; in the Monte Amiata region it begun in June 2003. From the day of installation, a periodic water sampling and manual measurement of the main physical and physicochemical parameters have been carried out on a monthly basis. Such activity has the double function of performing a cross-check of the monitoring instrumentation, and carrying out additional chemical and isotopic analysis. The continuous automatic monitoring stations operate with flowing water (about 5 litres per minute) and record the following parameters: temperature (T), pH, electrical conductivity (EC), redox potential (ORP) and the content of CO2 and CH4 dissolved in water. Data are

  1. Is rhizosphere remediation sufficient for sustainable revegetation of mine tailings?

    Science.gov (United States)

    Huang, Longbin; Baumgartl, Thomas; Mulligan, David

    2012-07-01

    Revegetation of mine tailings (fine-grained waste material) starts with the reconstruction of root zones, consisting of a rhizosphere horizon (mostly topsoil and/or amended tailings) and the support horizon beneath (i.e. equivalent to subsoil - mostly tailings), which must be physically and hydro-geochemically stable. This review aims to discuss key processes involved in the development of functional root zones within the context of direct revegetation of tailings and introduces a conceptual process of rehabilitating structure and function in the root zones based on a state transition model. Field studies on the revegetation of tailings (from processing base metal ore and bauxite residues) are reviewed. Particular focus is given to tailings' properties that limit remediation effectiveness. Aspects of root zone reconstruction and vegetation responses are also discussed. When reconstructing a root zone system, it is critical to restore physical structure and hydraulic functions across the whole root zone system. Only effective and holistically restored systems can control hydro-geochemical mobility of acutely and chronically toxic factors from the underlying horizon and maintain hydro-geochemical stability in the rhizosphere. Thereafter, soil biological capacity and ecological linkages (i.e. carbon and nutrient cycling) may be rehabilitated to integrate the root zones with revegetated plant communities into sustainable plant ecosystems. A conceptual framework of system transitions between the critical states of root zone development has been proposed. This will illustrate the rehabilitation process in root zone reconstruction and development for direct revegetation with sustainable plant communities. Sustainable phytostabilization of tailings requires the systematic consideration of hydro-geochemical interactions between the rhizosphere and the underlying supporting horizon. It further requires effective remediation strategies to develop hydro-geochemically stable

  2. Groundwater quality in an abandoned metal extraction site: the case study of Campello Monti (NW Italy)

    Science.gov (United States)

    Mehta, Neha; Lasagna, Manuela; Antonella Dino, Giovanna; De Luca, Domenico Antonio

    2017-04-01

    Extractive activities present threat to natural water systems and their effects are observed even after the cessation of activities. The harmful effects of extractive activities such as deterioration of water sources by low quality waters or by allowing leaching of metals into groundwater makes it necessary to carry out careful, scientific and comprehensive studies on this subject. Consequently, the same problem statement was chosen as part of a PhD research Project. The PhD research is part of REMEDIATE project (A Marie Sklodowska-Curie Action Initial Training Network for Improved decision making in contaminated land site investigation and risk assessment, Grant Agreement No. 643087). The current work thus points out on the contamination of groundwater sources due to past mining activities in the area. Contaminated groundwater may act as possible contamination source to surface water also. The impacts on water systems connected to mining activities depend on the ore type, metal being extracted, exploitation method, ore processing, pollution control efforts, geochemical and hydrogeochemical conditions of water and surroundings. To evaluate the effects posed by past metal extracting activities the study was carried out at an abandoned site used for extracting nickel in Campello Monti (Valstrona municipality, Piedmont region, Italy). Campello Monti is located in basement of Southern Italian Alps in the Ivrea Verbano Zone. The area is composed of mafic rocks intruded by mantle periodite. The mafic formation consists of peridotites, pyroxenites, gabbros, anorthosites, gabbro-norite, gabbro-diorite and diorite. Mines were used for nickel exploitation from 9th Century and continued until 1940s. The long history of nickel extraction has left the waste contaminated with Ni and Co in the mountains alongwith tunnels used for carrying out metal extracting activities. The area around the site is used for housing, shows the presence of domestic animals and has Strona creek

  3. Origin and structures of groundwater humic substances from three Danish aquifers

    DEFF Research Database (Denmark)

    Grøn, C.; Wassenaar, L.; Krog, M.

    1996-01-01

    and halogens, hydrolyzable amino acids and carbohydrates, carbon isotopes) applied to aquatic humic and fulvic acids led to consistent structural interpretations for each of the three aquifers studied. For humic substances in two-aquifers, the analyses suggested source rocks in agreement with geological...... and hydrogeochemical information. In a third aquifer, source rock identification was inconclusive, and multiple fossil and recent organic carbon sources are suggested....

  4. The potential for criticality following disposal of uranium at low-level waste facilities: Uranium blended with soil

    Energy Technology Data Exchange (ETDEWEB)

    Toran, L.E.; Hopper, C.M.; Naney, M.T. [and others

    1997-06-01

    The purpose of this study was to evaluate whether or not fissile uranium in low-level-waste (LLW) facilities can be concentrated by hydrogeochemical processes to permit nuclear criticality. A team of experts in hydrology, geology, geochemistry, soil chemistry, and criticality safety was formed to develop achievable scenarios for hydrogeochemical increases in concentration of special nuclear material (SNM), and to use these scenarios to aid in evaluating the potential for nuclear criticality. The team`s approach was to perform simultaneous hydrogeochemical and nuclear criticality studies to (1) identify some achievable scenarios for uranium migration and concentration increase at LLW disposal facilities, (2) model groundwater transport and subsequent concentration increase via sorption or precipitation of uranium, and (3) evaluate the potential for nuclear criticality resulting from potential increases in uranium concentration over disposal limits. The analysis of SNM was restricted to {sup 235}U in the present scope of work. The outcome of the work indicates that criticality is possible given established regulatory limits on SNM disposal. However, a review based on actual disposal records of an existing site operation indicates that the potential for criticality is not a concern under current burial practices.

  5. Uranium hydrogeochemical and stream sediment reconnaissance data release for the Elk City NTMS Quadrangle, Idaho/Montana, including concentrations of forty-five additional elements

    Energy Technology Data Exchange (ETDEWEB)

    Broxton, D.E.; Beyth, M.

    1980-07-01

    Totals of 1580 water and 1720 sediment samples were collected from 1754 locations in the quadrangle. Elemental concentration, field measurement, weather, geologic, and geographic data for each sample location are listed for waters in Appendix I-A and for sediments in Appendix I-B. Uranium/thorium ratios for sediment samples are also included in Appendix I-B. All elemental analyses were performed at the LASL. Water samples were initially analyzed for uranium by fluorometry. All water samples containing more than 40 parts per billion (ppB) uranium were reanalyzed by delayed-neutron counting (DNC). A supplemental report containing the multielement analyses of water samples will be open filed in the near future. Sediments were analyzed for uranium and thorium as well as aluminum, antimony, arsenic, barium, beryllium, bismuth, cadmium, calcium, cerium, cesium, chlorine, chromium, cobalt, copper, dysprosium, europium, gold, hafnium, iron, lanthanum, lead, lithium, lutetium, magnesium, manganese, nickel, niobium, potassium, rubidium, samarium, selenium, scandium, silver, sodium, strontium, tantalum, terbium, tin, titanium, tungsten, vanadium, ytterbium, zinc, and zirconium. Basic statistics for 40 of these elements are presented. All sediments were analyzed for uranium by delayed-neutron counting. Other elemental concentrations in sediments were determined by neutron-activation analysis for 30 elements, by x-ray fluorescence for 12 elements, and by arc-source emission spectrography for 2 elements. Analytical results for sediments are reported as parts per million.

  6. Raw data report of elemental analyses from hydrogeochemical and stream sediment samples taken near Sterling and Fort Morgan, Northeastern Colorado, December 1976 and January 1977

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, J.C.

    1977-03-01

    Water and sediment samples were collected from 125 sites near Sterling and Fort Morgan, Colorado, from Dec. 20, 1976, to Jan. 15, 1977. The samples were analyzed for U using fluorometry and delayed-neutron counting, and for various elements using emission spectrometry, energy-dispersive x-ray fluorometry, and neutron activation analysis. Several parameters were measured at each sample site during the sampling. The data from each sample site and for the elemental analyses are included in this document. (DLC)

  7. Linking a Large-Watershed Hydrogeochemical Model to a Wetland Community-Ecosystem Model to Estimate Plant Invasion Risk in the Coastal Great Lakes Region, USA

    Science.gov (United States)

    Currie, W. S.; Bourgeau-Chavez, L. L.; Elgersma, K. J.; French, N. H. F.; Goldberg, D. E.; Hart, S.; Hyndman, D. W.; Kendall, A. D.; Martin, S. L.; Martina, J. P.

    2014-12-01

    In the Laurentian Great Lakes region of the Upper Midwest, USA, agricultural and urban land uses together with high N deposition are contributing to elevated flows of N in rivers and groundwater to coastal wetlands. The functioning of coastal wetlands, which provide a vital link between land and water, are imperative to maintaining the health of the entire Great Lakes Basin. Elevated N inflows are believed to facilitate the spread of large-stature invasive plants (cattails and Phragmites) that reduce biodiversity and have complex effects on other ecosystem services including wetland N retention and C accretion. We enhanced the ILHM (Integrated Landscape Hydrology Model) to simulate the effects of land use on N flows in streams, rivers, and groundwater throughout the Lower Peninsula of Michigan. We used the hydroperiods and N loading rates simulated by ILHM as inputs to the Mondrian model of wetland community-ecosystem processes to estimate invasion risk and other ecosystem services in coastal wetlands around the Michigan coast. Our linked models produced threshold behavior in the success of invasive plants in response to N loading, with the threshold ranging from ca. 8 to 12 g N/m2 y, depending on hydroperiod. Plant invasions increased wetland productivity 3-fold over historically oligotrophic native communities, decreased biodiversity but slightly increased wetland N retention. Regardless of invasion, elevated N loading resulted in significantly enhanced rates of C accretion, providing an important region-wide mechanism of C storage. The linked models predicted a general pattern of greater invasion risk in the southern basins of lakes Michigan and Huron relative to northern areas. The basic mechanisms of invasion have been partially validated in our field mesocosms constructed for this project. The general regional patterns of increased invasion risk have been validated through our field campaigns and remote sensing conducted for this project.

  8. Uranium hydrogeochemical and stream sediment reconnaissance data release for the Dubois NTMS Quadrangle, Idaho/Montana, including concentrations of forty-five additional elements

    Energy Technology Data Exchange (ETDEWEB)

    LaDelfe, C.M.

    1980-08-01

    Totals of 1024 water samples and 1600 sediment samples were collected from 1669 locations in the Dubois quadrangle. Water samples were taken at streams, springs, and wells; sediment samples were collected from streams and springs. All field and analytical data are presented for waters in Appendix I-A and for sediments in I-B. All elemental analyses were performed at the LASL. Water samples were initially analyzed for uranium by fluorometry. All water samples containing more than the upper detection limit of uranium were reanalyzed by delayed neutron counting. Sediments were analyzed for uranium and thorium as well as aluminum, antimony, arsenic, barium, beryllium, bismuth, cadmium, calcium, cerium, cesium, chlorine, chromium, cobalt, copper, dysprosium, europium, gold, hafnium, iron, lanthanum, lead, lithium, lutetium, magnesium, manganese, nickel, niobium, potassium rubidium, samarium, scandium, selenium, silver, sodium, strontium, tantalum, terbium, tin, titanium, tungsten, vanadium, ytterbium, zinc and zirconium. All sediments were analyzed for uranium by delayed-neutron counting. Other elemental concentrations in sediments were determined by neutron-activation analysis for 30 elements, by x-ray fluorescence for 12 elements, and by arc-source emission spectrography for 2 elements. Analytical results for sediments are reported as parts per million.

  9. Hydrogeochemical and mineralogical effects of sustained CO2 contamination in a shallow sandy aquifer: A field-scale controlled release experiment

    DEFF Research Database (Denmark)

    Cahill, Aaron Graham; Marker, Pernille Aabye; Jakobsen, Rasmus

    2014-01-01

    were taken pre and postinjection and analyzed to search for effects on mineralogy and sediment properties. Results showed the simulated leak to evolve in two distinct phases; an advective elevated ion pulse followed by increasing persistent acidification. Spatial and temporal differences in evolution...

  10. 3DHYDROGEOCHEM: A 3-DIMENSIONAL MODEL OF DENSITY-DEPENDENT SUBSURFACE FLOW AND THERMAL MULTISPECIES-MULTICOMPONENT HYDROGEOCHEMICAL TRANSPORT (EPA/600/SR-98/159)

    Science.gov (United States)

    This report presents a three-dimensional finite-element numerical model designed to simulate chemical transport in subsurface systems with temperature effect taken into account. The three-dimensional model is developed to provide (1) a tool of application, with which one is able ...

  11. National Uranium Resource Evaluation Program. Hydrogeochemical and stream sediment reconnaissance basic data for Beeville NTMS Quadrangle, Texas. Uranium resource evaluation project

    Energy Technology Data Exchange (ETDEWEB)

    1979-10-31

    Results of a reconnaissance geochemical survey of the Beeville Quadrangle, Texas are reported. Field and laboratory data are presented for 373 groundwater and 364 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the survey area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. The groundwater data indicate that the northwestern corner of the quadrangle is the most favorable for potential uranium mineralization. Favorability is indicated by high uranium concentrations; high arsenic, molybdenum, and vanadium concentrations; and proximity and similar geologic setting to the mines of the Karnes County mining district. Other areas that appear favorable are an area in Bee and Refugio Counties and the northeastern part of the quadrangle. Both areas have water chemistry similar to the Karnes County area, but the northeastern area does not have high concentrations of pathfinder elements. The stream sediment data indicate that the northeastern corner of the quadrangle is the most favorable for potential mineralization, but agricultural practices and mineralogy of the outcropping Beaumont Formation may indicate a false anomaly. The northwestern corner of the quadrangle is considered favorable because of its proximity to the known uranium deposits, but the data do not seem to support this.

  12. Hydrogeochemical characteristics and genesis of the high-temperature geothermal system in the Tashkorgan basin of the Pamir syntax, western China

    Science.gov (United States)

    Li, Yiman; Pang, Zhonghe; Yang, Fengtian; Yuan, Lijuan; Tang, Pinghui

    2017-11-01

    High-temperature geothermal systems in China, such as those found in Tenchong and Tibet, are common. A similar system without obvious manifestations found in the Tashkorgan basin in the western Xinjiang Autonomous Region, however, was not expected. The results from borehole measurements and predictions with geothermometers, such as quartz, Na-K and Na-K-Mg, indicate that the reservoir temperature is approximately 250-260 °C. Geothermal water is high in Total Dissolved Solids (>2.5 g/L) and SiO2 content (>273 mg/L), and the water type is Cl·SO4-Na, likely resulting from water-rock interactions in the granodiorite reservoirs. Based on isotope analysis, it appears to be recharged by local precipitation and river water. Evidence from the relationships between major ions and the Cl and molar Na/Cl ratio suggests mixing between deep geothermal water and shallow cold groundwater during the upwelling process. Mixing ratios calculated by the relationship between Cl and SiO2 show that the proportion from cold end-members are 96-99% and 40-90% for riparian zone springs and geothermal water from boreholes, respectively. Active regional tectonic and Neo-tectonic movements in the Pamir syntax as well as radioactive elements in the granodiorite reservoir of the Himalayan stage provide basis for the high heat flow background (150-350 mW/m2). NNW trending fault systems intersecting with overlying NE faults provide circulation conduits with high permeability for geothermal water.

  13. Uranium hydrogeochemical and stream sediment reconnaissance data from the area of the Shishmaref, Kotzebue, Selawik and Shungnak Quadrangles, northern Seward Peninsula and vicinity, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Warren, R.G.; Hill, D.E.; Sharp, R.R. Jr.

    1978-05-01

    During the summer of 1976, 1336 water and 1251 sediment samples were collected for Los Alamos Scientific Laboratory (LASL) from 1356 streams and small lakes or ponds within Shishmaref, Kotzebue, Selawik, and western portion of Shungnak NTMS quadrangles in western Alaska. Both a water and sediment sample were generally obtained from each location at a nominal location density of 1/23 km/sup 2/. Total uranium was measured in waters by fluorometry and in sediments and a few waters by delayed neutron counting at LASL. Uranium concentrations in waters have a mean of 0.31 ppB and a maximum of 9.23 ppB, and sediments exhibit a mean of 3.44 ppM and a maximum of 37.7 ppM. A large number of high-uranium concentrations occur in both water and sediment samples collected in the Selawik Hills. At least two locations within the Selawik Hills appear favorable for further investigation of possible uranium mineralization. A cluster of high-uranium sediments, seen in the Waring Mountains, are probably derived from a lower Cretaceous conglomerate unit which is assocated with known airborne radiometric anomalies. Apparently less favorable areas for further investigation of possible uranium mineralization are also located in the Waring Mountains and Kiana Hills. Additional samples were collected within the Shungnak quadrange to increase the sampling density used elsewhere in the area to about one location per 11 km/sup 2/ (double-density). Contoured plots of uranium concentrations for both waters and sediments were prepared for all double-density sample locations, and then for the even-numbered and odd-numbered locations separately. These plots indicate that the HSSR sampling density of 1/23 km/sup 2/ used in lowland areas of Alaska provide essentially the same definition of relative areal uranium distributions in waters and sediments as seen when the density is doubled. These plots indicate that regional distribution patterns for uranium are well defined without selective sampling of geologic units.

  14. Arsenic enrichment and mobilization in the Holocene alluvial aquifers of the Chapai-Nawabganj district, Bangladesh: A geochemical and statistical study

    Energy Technology Data Exchange (ETDEWEB)

    Reza, A.H.M. Selim [Department of Earth Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Jean, Jiin-Shuh, E-mail: Jiinshuh@mail.ncku.edu.tw [Department of Earth Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Lee, Ming-Kuo [Department of Geology and Geography, Auburn University, Auburn, AL 36849 (United States); Yang, Huai-Jen; Liu, Chia-Chuan [Department of Earth Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China)

    2010-08-15

    Research highlights: {yields} Four factors (i.e., salinity factor, As-enrichment factor, reduction factor, and hardness factor) control groundwater geochemistry. {yields} Hydrochemical facies analysis showed that most of the water samples are dominated by Ca and HCO{sub 3} ions. {yields} Cluster 1 water types are highly enriched in As; an alternative water source is thus needed for domestic water supply. Possible solutions are to install tube wells in the deeper Pleistocene aquifers or use clean surface water sources such as reservoirs or rain water. {yields} Cluster 4 water types contain low concentration As, below the Bangladesh standard (<50 {mu}g/L), and this type of water is generally suitable for extraction for domestic uses. {yields} Statistical analyses show that As, Fe and Mn are strongly correlated in sediments. By comparison, As is not correlated with Fe but is positively correlated with Mn in groundwater. {yields} Geochemical correlations along with results of sequential leaching experiments suggest that bacterial reductive dissolution of MnOOH and FeOOH is the primary mechanism for releasing As into the groundwater. {yields} Geochemical studies using sequential-extraction results and scanning electron microscopy on sediment samples demonstrate that Fe- and Mn-oxyhydroxides and Fe- and Mn-oxyhydroxide-coated quartz and feldspar, are the dominant carriers of As in the sediments. - Abstract: Core sediments from three boreholes (to a depth of 50 m) and groundwater from 20 As-enriched water wells were collected in the Chapai-Nawabganj area of northwestern Bangladesh for geochemical analyses. Multivariate statistical analyses including factor analysis, cluster analysis and multidimensional scaling were applied to the hydrogeochemical data. The results show that a few factors adequately represent the traits that define water chemistry. Sodium, Cl, SO{sub 4}, total dissolved solids (TDS), and electrical conductivity (EC) are grouped under the first factor

  15. Rare earth and trace element signatures for assessing an impact of rock mining and processing on the environment: Wiśniówka case study, south-central Poland.

    Science.gov (United States)

    Migaszewski, Zdzisław M; Gałuszka, Agnieszka; Dołęgowska, Sabina

    2016-12-01

    A detailed hydrogeochemical study was performed in the Wiśniówka mining area (south-central Poland). This covered three acid pit bodies, historic tailings acid ponds, acid pools, and additionally two neighboring rivers. All these acid mine drainage (AMD) waters are characterized by the pH in the range of 1.7 (pools) to 3.5 (tailings ponds). The most interesting is the Podwiśniówka acid pit lake that shows a very low pH (2.2-2.5) and very high concentrations of SO4(2-) (2720-5460 mg/L), Fe (545-1140 mg/L), Al (86.2 mg/L), As (9603-24,883 μg/L), Co (1317-3458 μg/L), Cr (753-2047 μg/L), Cu (6307-18,879 μg/L), Ni (1168-3127 μg/L), and rare earth element (REE) (589-1341 μg/L). In addition, seeps that drain the Podwiśniówka mine tailings and partly aggregate piles form strong acid pools in the mining area. Along with these pools, in which As and REE contents reach 369,726 and 6288 μg/L, respectively, these waters are among the most distinctive As- and REE-rich AMD surface waters across the world. It is noteworthy that the Podwiśniówka acid pit lake and Wiśniówka Duża acid pit sump exhibit different element signatures and REE concentration patterns normalized to North American Composite Shale (NASC): the Podwiśniówka acid pit lake always shows a characteristic roof-shaped medium REE (MREE) profile with distinct enrichments in Gd, Eu, and Tb whereas the other one displays a step-shaped heavy REE (HREE) profile with positive Tb and Gd anomalies. The REE undergo fractionation during weathering and the subsequent leaching of dissolved and suspended fractions from rocks to acid water bodies where these and other elements are further fractionated by geochemical processes. This study shows that the individual REE have greater affinities for Mn, HREE for Fe and SO4(2-), and only La and Ce for Al. This specific water geochemistry has enabled us to (i) pinpoint the location of AMD "hot spots" originated from quartzite mining and processing operations

  16. Bedrock Hydrogeology - Site investigation SFR

    Energy Technology Data Exchange (ETDEWEB)

    Oehman, Johan [Geosigma AB, Stockholm (Sweden); Bockgaard, Niclas [Golder Assoes AB, Stockholm (Sweden); Follin, Sven [SF GeoLogic AB, Taeby (Sweden)

    2012-06-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) has conducted site investigations for a planned extension of the existing final repository for short-lived radioactive waste (SFR). This report presents an integrated analysis and interpretation of the historic data from the existing SFR (1980 - 1986), as well as, from the recent investigations for the planned extension of SFR (2008 - 2009). The primary objective is to establish a conceptual hydrogeological model of the bedrock for safety assessment and design analyses. Analyses and interpretations of all (old and new) hydraulic data are analysed with regard to the recently developed geological deformation zone model of the SFR model domain (Curtis et al. 2011). The methodology used by Curtis et al. (2011) has focussed on magnetic anomalies and deformation zone intercepts with ground surface greater than 300 m. In the hydrogeological modelling, however, it has been considered important to also explore the occurrence and characteristics of shallow horizontal to sub-horizontal structures (sheet joints) inside the SFR model domain. Such structures are of considerable importance for the hydrogeology in the uppermost c. 150 m of bedrock in SDM-Site Forsmark; hence the term Shallow Bedrock Aquifer was used to emphasise their hydraulic significance. In this study, the acronym SBA-structure is used for horizontal structures identified in the hydrogeological modelling. In addition to the predominantly steeply dipping geological deformation zones, eight so-called SBA-structures are modelled deterministically in the hydrogeological model. The SBA-structures are envisaged as hydraulically heterogeneous and composed of clusters of minor gently dipping to horizontal fractures rather than extensive single features. A type of structures that is partly included in the definition of the SBA-structures is the Unresolved Possible Deformations Zone (Unresolved PDZ) intercepts identified by Curtis et al. (2011). The Unresolved

  17. Qualitative studies

    National Research Council Canada - National Science Library

    Qualitative Studies (QS) aims to become a central forum for discussions of qualitative research in psychology, education, communication, cultural studies, health sciences and social sciences in general...

  18. 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

    Radioactive waste from nuclear power plants in Sweden is managed by the Swedish Nuclear Fuel and Waste Management Co, SKB. SKB has performed site investigations at two different locations in Sweden, referred to as the Forsmark and Laxemar-Simpevarp areas, with the objective of siting a final repository for high-level radioactive waste. In 2009 a decision was made to focus on the Forsmark site. This decision was based on a large amount of empirical evidence suggesting Forsmark to be more suitable for a geological repository /SKB 2010b/. This report presents model results of numerical flow and transport modelling of surface water and near-surface groundwater at the Forsmark site for present and future conditions. Both temperate and periglacial climates have been simulated. Also different locations of the shoreline have been applied to the model, as well as different models of vegetation and Quaternary deposits. The modelling was performed using the modelling tool MIKE SHE and was based on the SDM-Site Forsmark MIKE SHE model (presented by Bosson et al. in SKB report R-08-09). The present work is a part of the biosphere modelling performed for the SR-Site safety assessment. The Forsmark area has a flat, small-scale topography. The study area is almost entirely below 20 m.a.s.l. (metres above sea level). There is a strong correlation between the topography of the ground surface and the ground water level in the Quaternary deposits (QD); thus, the surface water divides and the groundwater divides for the QD can be assumed to coincide. No major water courses flow through the catchment. Small brooks, which often dry out in the summer, connect the different sub-catchments with each other. The main lakes in the area, Lake Bolundsfjaerden, Lake Fiskarfjaerden, Lake Gaellsbotraesket and Lake Eckarfjaerden, all have sizes of less than one km2. The lakes are in general shallow. Approximately 70% of the catchment areas are covered by forest. Agricultural land is only present in

  19. Study Drugs

    Science.gov (United States)

    ... What Are Study Drugs? Doctors prescribe medicines like Adderall and Ritalin to treat conditions like attention deficit ... stimulants are used as study drugs: amphetamines like Adderall, Dexedrine, or Vyvanse methylphenidates like Ritalin or Concerta ...

  20. Cystometric study

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003904.htm Cystometric study To use the sharing features on this page, please enable JavaScript. Cystometric study measures the amount of fluid in the bladder ...

  1. Initial Study

    DEFF Research Database (Denmark)

    Torp, Kristian

    2009-01-01

    increased. In the initial study presented here, the time it takes to pass an intersection is studied in details. Two major signal-controlled four-way intersections in the center of the city Aalborg are studied in details to estimate the congestion levels in these intersections, based on the time it takes...

  2. HTS Teologiese Studies / Theological Studies

    African Journals Online (AJOL)

    HTS Teologiese Studies/Theological Studies is an acclaimed Open Access journal with broad coverage that promotes multidisciplinary, religious, and biblical aspects of studies in the international theological arena. The journal's publication criteria are based on high ethical standards and the rigor of the methodology and ...

  3. Europaian Studies

    OpenAIRE

    Manners, Ian

    2003-01-01

    This article is written for the special issue on European Studies and reflects on 45 years of theorising contemporary Europe, within the context of broader developments in the social sciences. What is immediately clear to anyone reading this article, the Journal of Contemporary European Studies, Journal of  Common Market Studies, Journal of European Public Policy, Journal of European Integration, or any of the many other established journals of contemporary or any of the many other establishe...

  4. INTERHEART STUDY

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. INTERHEART STUDY. About 90% of CHD Risk (“PAR”) can be explained by 9 Risk Factors: Smoking. Dyslipidemia. High BP. Diabetes. Abdominal Obesity. Psychosocial Factors. Fruits & Vegetables. Exercise. Alcohol.

  5. ACTIVITY STUDIES

    African Journals Online (AJOL)

    2-HYDROXY-4-METHOXYBENZALDEHYDE: LARVICIDAL STRUCTURE-. ACTIVITY STUDIES. Geoffrey M. Mahangal, Teresa O. Akengal, Wilber Lwandez, Isaiah 0. ... 2Behavioural and Chemical Ecology Department, International Centre for Insect Physiology and .... Y = mean death count, X = initial larvae population'.

  6. Floodplain Study

    Data.gov (United States)

    Montgomery County of Maryland — The purpose of a floodplain study is to establish the 100-year floodplain limits within or near a development in order to preserve the natural resources within the...

  7. Actuarial Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Office of the Actuary in the Centers for Medicare and Medicaid Services (CMS) from time to time conducts studies on various aspects of the Medicare and Medicaid...

  8. European Studies

    Directory of Open Access Journals (Sweden)

    V. O. Pechatnov

    2014-01-01

    Full Text Available The study of Western countries and teaching courses on the related subjects have longstanding and established tradition at MGIMO-University. The basis of this brilliant research and teaching tradition was laid down by such academicians as E.V. Tarle and V.G. Trukhanovsky, Professor L.I. Clove, Y. Borisov, F.I. Notovitch, G.L. Rozanov. Their work in 1940-1960's at the Department of World History at MGIMO-University progressed in following directions: France studies, German studies, American studies. The work resulted in a number of monographs and textbooks on modern history and foreign policy of the studied countries and regions. The aim of the publications was dictated by the goal of the Institute - to prepare the specialists in international affairs primarily for practical work. A close relationship with the Foreign Ministry was "binding advantage" sometimes limiting researchers in choosing periods and subjects for the study. At the same time the undisputed advantage and quality of regional studies at MGIMO were strengthened by the practical relevance of research, making it a vital and interesting not only for specialists but also for students and researchers from other research centers. Another characteristic of the tradition is the analysis of foreign policy and diplomacy in a close relationship with the socio-economic and political processes. Such an integrated approach to regional geography also formed largely under the influence of institutional profile designed to train highly skilled and versatile specialists in specific countries and regions with a good knowledge of their languages, history, economics, politics, law and culture. Therefore, scientific and educational-methodical work at MGIMO-University has always relied on a wealth of empirical data and has been focused on the analysis of real-world phenomena and processes, acute problems of foreign countries. Scientific research at MGIMO-University traditionally intertwined with

  9. Clinical Studies

    DEFF Research Database (Denmark)

    Pallesen, Ulla

    universities and practicing dentists restore millions of teeth throughout the World with composite resin materials. Do we know enough about the clinical performance of these restorations over time? Numerous in vitro studies are being published on resin materials and adhesion, some of them attempting to imitate...... and results from own up to 30-year prospective clinical university studies and practice based studies from Public Dental Health Service on the clinical performance of posterior composite resin restorations.......Within the last 25 years composite resin materials have in many countries successively replaced amalgam as a restorative for posterior teeth. Resin materials and bonding systems are continuously being improved by the manufactures, adhesive procedures are now included in the curriculum of most...

  10. Studying Sideways

    DEFF Research Database (Denmark)

    Plesner, Ursula

    2011-01-01

    inequalities in relation to the people we study. This article argues that not all types of social scientific research interviews benefit from an à priori problematization of power and control, ethics and equality, or emancipation. From a constructivist perspective, the article seeks to displace...... and researched share professional background to some degree, where negotiations replace a researcher-imposed dialogue, and where the circulation of shared or common concepts messes up an orderly division between researchers’ vocabulary and interviewees’ vocabularies. It is proposed that when we study sideways...

  11. Study Proposal

    African Journals Online (AJOL)

    MATHEMATICS DEPARTMENT

    Msc in Mathematics Faculty of Education, Jimma University, Jimma, Ethiopia. P. O. Box 378 ..... Inquiry was made to know factors affecting their study of mathematics ..... mathematics. English language for teaching mathematics must start right at. 7th grade, and make it practical and applied. ▫ In Ethiopia we have no system of.

  12. Study Strategies

    DEFF Research Database (Denmark)

    Nielsen, Camilla Kirketerp; Noer, Vibeke Røn

    ID: 1277 / 22 SES 06 B: 2 22. Research in Higher Education Format of Presentation: Paper Alternative EERA Network: 19. Ethnography Topics: NW 22: Teaching, learning and assessment in higher education Keywords: Profession-oriented learning, study strategies, professionalisation processes, comparat......ID: 1277 / 22 SES 06 B: 2 22. Research in Higher Education Format of Presentation: Paper Alternative EERA Network: 19. Ethnography Topics: NW 22: Teaching, learning and assessment in higher education Keywords: Profession-oriented learning, study strategies, professionalisation processes......, comparative cross-disciplinary ethnography Study Strategies – Crossing Contexts Camilla Kirketerp Nielsen 1, Vibeke Røn Noer 2,1 1 University of Copenhagen, Denmark; 2 VIA University College Presenting Author: Kirketerp Nielsen, Camilla; Røn Noer, Vibeke This paper provides comparative cross...... module”. The projects differ in terms of both starting point and main focus of research (an alternative educational model and profession-orientated Game-based learning). However, in the on-going process of research, an empirical ´harmony´ on common recurrent themes related to students `study strategies...

  13. CASE STUDY

    African Journals Online (AJOL)

    BY TOXOPLASMOSIS. CASE STUDY. Christine Katusiime1, MB ChB, PGDPPM. Ponsiano Ocama2, MB ChB, MMed. Andrew Kambugu1, MB ChB, MMed. 1Makerere University, College of Health Sciences, Infectious Diseases Institute, Kampala, Uganda. 2Makerere University, College of Health Sciences, Department of ...

  14. Club studies

    DEFF Research Database (Denmark)

    Demant, Jakob Johan; Ravn, Signe; Harder, Sidsel Kirstine

    2010-01-01

    suggests a mixed-methods approach to club studies that combine quantitative data, qualitative interviews and ethnography conducted in the club space. By introducing the concept of ‘socionautics', this review suggests that the researcher travels into the social landscape of youth, clubs and drugs...

  15. Colour Studies

    African Journals Online (AJOL)

    DR Nneka

    2015-04-14

    Apr 14, 2015 ... colour thus: Color can sway thinking, change actions, and cause reactions. It can irritate or soothe your eyes, raise your blood pressure and suppress ... object and something like a fire from the eye, which sees as a spirit or soul ..... Finally, the study of one's own subjective colour preferences and the field of.

  16. CASE STUDY

    African Journals Online (AJOL)

    2011-06-02

    AIDS Control Programme, Sri Lanka. CASE STUDY. A 49-year-old male security supervisor was admitted to hospital with recurrent chest infections. He was found to be HIV positive with a CD4 count of 60 cells/µl, and was.

  17. Studying CO

    NARCIS (Netherlands)

    Boullenger, B.; Verdel, A.; Paap, B.; Thorbecke, J.; Draganov, D.

    2014-01-01

    Seismic interferometry applied to ambient-noise measurements allows the retrieval of the seismic response between pairs of receivers. We studied ambient-noise seismic interferometry (ANSI) to retrieve time-lapse reflection responses from a reservoir during CO2 geologic sequestration,

  18. Research Study

    Science.gov (United States)

    Glick, Ashley

    2010-01-01

    Background: Action Research about my 2nd grade classroom in the Buffalo School District. I examined three areas of interest and tried to find some conclusions related to behavior management. Purpose: The purpose of this study is how will implementing procedures, rules, and consequences help improve student behavior. Research Design: Descriptive;…

  19. Study protocol

    DEFF Research Database (Denmark)

    Madsen, Helle Østergaard; Dam, Ole Henrik; Hageman, Ida

    2012-01-01

    yields a Global Seasonal Score and a prevalence of SAD. Outcomes from the two groups will be compared. Moreover, outcomes from subgroups of the visually impaired population will be compared. ETHICS AND DISSEMINATION: The study is approved by the Danish Data Protection Agency. Results will be published...

  20. Based Study

    African Journals Online (AJOL)

    A prospective community-based study of pregnant women in rural communi- ties of south central Ethiopia ... pregnancy outcome were stillbirth (19/1000 births), perinatal mortality (45/1000 births) and neonatal mortality (37/1000 live births). Poor birth ..... ated widi maternal under-nutrition and age (teen- agers giving birdi to ...

  1. The experimental facility of Tournemire; La station experimentale de Tournemire

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-10-01

    This document presents the underground facility of Tournemire (Aveyron, France). The Tournemire abandoned railway tunnel gives access to a 250 m thick Jurassic clay bed covered with 250 m of limestones. The main goal of the Tournemire project is the study of the mechanical properties and fracturing of a clay formation and of its ability to be used as a deep underground storage facility for radioactive wastes. The document comprises a general presentation brochure and a description of the geologic, tectonic, geomechanical and hydro-geochemical surveys carried out in the facility. (J.S.)

  2. Groundwater chemistry of the Oban Massif, South-Eastern Nigeria

    Directory of Open Access Journals (Sweden)

    Solomon John Ekwere

    2012-04-01

    Full Text Available Hydrogeochemical study of the fractured/weathered basement of the Oban Massif, southeastern Nigeria has been carried out. Results indicated that concentrations of major cations and anions exhibited the following order of abundance: Ca>Na>Mg>K and HCO3>SO4>Cl, respectively, with minor variations across sampling seasons. Ca-Na-Cl-SO4 and Ca-Mg-HCO3 water types have been identified as major facies, resultant from congruent influences of weathering (mainly silicates, ion exchange processes, and water mixing.

  3. Study protocol

    DEFF Research Database (Denmark)

    Thorsteinsson, Troels; Helms, Anne Sofie; Adamsen, Lis

    2013-01-01

    . Secondary endpoints are quality of life measured by validated questionnaires and interviews, and physical performance. RESPECT includes a multimodal intervention program, including ambassador-facilitated educational, physical, and social interventions. The educational intervention includes an educational...... to interaction with peers.Methods/design: The RESPECT study is a nationwide population-based prospective, controlled, mixed-methods intervention study looking at children aged 6-18 years newly diagnosed with cancer in eastern Denmark (n = 120) and a matched control group in western Denmark (n = 120). RESPECT...... program aimed at the child with cancer, the child's schoolteachers and classmates, and the child's parents. Children with cancer will each have two ambassadors assigned from their class. The ambassadors visit the child with cancer at the hospital at alternating 2-week intervals and participate...

  4. Project studies

    DEFF Research Database (Denmark)

    Geraldi, Joana; Söderlund, Jonas

    2018-01-01

    Project organising is a growing field of scholarly inquiry and management practice. In recent years, two important developments have influenced this field: (1) the study and practice of projects have extended their level of analysis from mainly focussing on individual projects to focussing on micro......- as well as macro-level concerns around projects; and (2) there has been a greater interest in different kinds of scholarly inquiry. Taken together, these two developments call for closer scrutiny of how the levels of analysis and the types of inquiry are related and benefit each other...... project research: (1) levels of analysis; and (2) type of research. Analysing recent developments within project studies, we observe the emergence of what we refer to as type 3 research, which reconciles the need for theoretical development and engagement with practice. Type 3 research suggests pragmatic...

  5. Invisibility Studies

    DEFF Research Database (Denmark)

    Invisibility Studies explores current changes in the relationship between what we consider visible and what invisible in different areas of contemporary culture. Contributions trace how these changes make their marks on various cultural fields and investigate the cultural significance...... conditioned by physical and social settings that create certain possibilities for visibility and visuality, yet exclude others. The richness and complexity of this cultural framework means that no single discipline or interdisciplinary approach could capture it single-handedly. Invisibility Studies begins...... this conversation by bringing together scholars across the fields of architectural history and theory, art, film and literature, philosophy, cultural theory and contemporary anthropology as well as featuring work by a collective of artists....

  6. Security Studies

    OpenAIRE

    ,

    2005-01-01

    Security Studies has firmly established itself as a leading journal on international security issues. The journal publishes theoretical, historical and policy-oriented articles on the causes and consequences of war, and the sources and conditions of peace. The journal has published articles on balancing vs. bandwagoning, deterrence in enduring rivalries, the Domino theory, nuclear weapons proliferation, civil-military relations, political reforms in China, strategic culture in Asia and the P...

  7. A field-scale reactive transport model for U(VI) migration influenced by coupled multirate mass transfer and surface complexation reactions

    Science.gov (United States)

    Ma, R.; Zheng, C.; Prommer, H.; Greskowiak, J.; Liu, C.; Zachara, J.; Rockhold, M.

    2010-05-01

    This study explores field-scale modeling of U(VI) reactive transport through incorporation of laboratory and field data. A field-scale reactive transport model was developed on the basis of laboratory-characterized U(VI) surface complexation reactions (SCRs) and multirate mass transfer processes, as well as field-measured hydrogeochemical conditions at the U.S. Department of Energy, Hanford 300 Area (300 A), Washington. The model was used to assess the importance of multirate mass transfer processes on U(VI) reactive transport and to evaluate the effect of variable geochemical conditions caused by dynamic river water-groundwater interactions on U(VI) plume migration. Model simulations revealed complex spatiotemporal relationships between groundwater composition and U(VI) speciation, adsorption, and plume migration. In general, river water intrusion enhances uranium adsorption and lowers aqueous uranium concentration because river water dilution increases pH and decreases aqueous bicarbonate concentration, leading to overall enhanced U(VI) surface complexation. Strong U(VI) retardation was computed for the field-measured hydrogeochemical conditions, suggesting a slow dissipation of the U(VI) plume, a phenomenon consistent with field observations. The simulations also showed that SCR-retarded U(VI) migration becomes more dynamic and synchronous with the groundwater flow field when multirate mass transfer processes are involved. Breakthrough curves at selected locations and the temporal changes in the calculated mass during the 20 year simulation period indicated that uranium adsorption/desorption never attained steady state because of the dynamic flow field and groundwater composition variations caused by river water intrusion. Thus, the multirate SCR model appears to be a crucial consideration for future reactive transport simulations of uranium contaminants at the Hanford 300 A site and elsewhere under similar hydrogeochemical conditions.

  8. Change in cap rock porosity triggered by pressure and temperature dependent CO2–water–rock interactions in CO2 storage systems

    Directory of Open Access Journals (Sweden)

    Christina Hemme

    2017-03-01

    Full Text Available Carbon capture and storage in deep geological formations is a method to reduce greenhouse gas emissions. Supercritical CO2 is injected into a reservoir and dissolves in the brine. Under the impact of pressure and temperature (P–T the aqueous species of the CO2-acidified brine diffuse through the cap rock where they trigger CO2–water–rock interactions. These geochemical reactions result in mineral dissolution and precipitation along the CO2 migration path and are responsible for a change in porosity and therefore for the sealing capacity of the cap rock. This study focuses on the diffusive mass transport of CO2 along a gradient of decreasing P–T conditions. The process is retraced with a one-dimensional hydrogeochemical reactive mass transport model. The semi-generic hydrogeochemical model is based on chemical equilibrium thermodynamics. Based on a broad variety of scenarios, including different initial mineralogical, chemical and physical parameters, the hydrogeochemical parameters that are most sensitive for safe long-term CO2 storage are identified. The results demonstrate that P–T conditions have the strongest effect on the change in porosity and the effect of both is stronger at high P–T conditions because the solubility of the mineral phases involved depends on P–T conditions. Furthermore, modeling results indicate that the change in porosity depends strongly on the initial mineralogical composition of the reservoir and cap rock as well as on the brine compositions. Nevertheless, a wide range of conditions for safe CO2 storage is identified.

  9. Studying Emerge

    DEFF Research Database (Denmark)

    Davies, Sarah Rachael; Selin, Cynthia; Rodegher, Sandra

    2015-01-01

    The Emerge event, held in Tempe, AZ in March 2012, brought together a range of scientists, artists, futurists, engineers and students in order to experiment with innovative methods for thinking about the future. These methodological techniques were tested through nine workshops, each of which made...... use of a different format; Emerge as a whole, then, offered an opportunity to study a diverse set of future-oriented engagement practices. We conducted an event ethnography, in which a team of 11 researchers collaboratively developed accounts of the practices at play within Emerge and its workshops...

  10. Economic Studies

    Directory of Open Access Journals (Sweden)

    A. V. Kholopov

    2014-01-01

    Full Text Available The establishment of the School of Economic Science at MGIMO was due to the necessity of the world economy research, and the need to prepare highly skilled specialists in international economics. The school is developing a number of areas, which reflect the Faculty structure. - Economic theory is one of the most important research areas, a kind of foundation of the School of Economic Science at MGIMO. Economic theory studies are carried out at the chair of Economic theory. "The course of economic theory" textbook was published in 1991, and later it was reprinted seven times. Over the past few years other textbooks and manuals have been published, including "Economics for Managers" by Professor S.N. Ivashkovskaya, which survived through five editions; "International Economics" - four editions and "History of Economic Thought" - three editions. - International Economic Relations are carried out by the Department of International Economic Relations and Foreign Economic Activity. Its establishment is associated with the prominent economist N.N. Lyubimov. In 1957 he with his colleagues published the first textbook on the subject which went through multiple republications. The editorial team of the textbook subsequently formed the pride of Soviet economic science - S.M. Menshikov, E.P. Pletnev, V.D. Schetinin. Since 2007, the chair of Foreign Economic Activities led by Doctor of Economics, Professor I. Platonova has been investigating the problems of improving the architecture of foreign economic network and the international competitiveness of Russia; - The history of the study of problems of the world economy at MGIMO begins in 1958 at the chair baring the same name. Since 1998, the department has been headed by Professor A. Bulatov; - The study of international monetary relations is based on the chair of International Finance, and is focused on addressing the fundamental scientific and practical problems; - The chair "Banks, monetary circulation

  11. Law Studies

    Directory of Open Access Journals (Sweden)

    G. P. Tolstopiatenko

    2014-01-01

    Full Text Available At the origin of the International Law Department were such eminent scientists, diplomats and teachers as V.N. Durdenevsky, S.B. Krylov and F.I. Kozhevnikov. International law studies in USSR and Russia during the second half of the XX century was largely shaped by the lawyers of MGIMO. They had a large influence on the education in the international law in the whole USSR, and since 1990s in Russia and other CIS countries. The prominence of the research of MGIMO international lawyers was due to the close connections with the international practice, involving international negotiations in the United Nations and other international fora, diplomatic conferences and international scientific conferences. This experience is represented in the MGIMO handbooks on international law, which are still in demand. The Faculty of International Law at MGIMO consists of seven departments: Department of International Law, Department of Private International and Comparative Law; Department of European Law; Department of Comparative Constitutional Law; Department of Administrative and Financial Law; Department of Criminal Law, Department Criminal Procedure and Criminalistics. Many Russian lawyers famous at home and abroad work at the Faculty, contributing to domestic and international law studies. In 1947 the Academy of Sciences of the USSR published "International Law" textbook which was the first textbook on the subject in USSR. S.B. Krylov and V.N. Durdenevsky were the authors and editors of the textbook. First generations of MGIMO students studied international law according to this textbook. All subsequent books on international law, published in the USSR, were based on the approach to the teaching of international law, developed in the textbook by S.B. Krylov and V.N. Durdenevsky. The first textbook of international law with the stamp of MGIMO, edited by F.I. Kozhevnikov, was published in 1964. This textbook later went through five editions in 1966, 1972

  12. Conceptual study

    Energy Technology Data Exchange (ETDEWEB)

    Harty, H.

    1978-09-01

    This appendix is a compendium of topical reports prepared for the Hanford Nuclear Energy Center: Status Report: Conceptual Fuel Cycle Studies for the Hanford Nuclear Energy Center; Selection of Heat Disposal Methods for a Hanford Nuclear Energy Center; Station Service Power Supply for a Hanford Nuclear Energy Center (HNEC); Impact of a Hanford Nuclear Energy Center on Ground Level Fog and Humidity; A Review of Potential Technology for the Seismic Characterization of Nuclear Energy Centers; Reliability of Generation at a Hanford Nuclear Energy Center (HNEC); Meteorological Evaluation of Multiple Reactor Contamination Probabilities for a Hanford Nuclear Energy Center; Electric Power Transmission for a Hanford Nuclear Energy Center (HNEC); The Impact of a Hanford Nuclear Energy Center on Cloudiness and Insolation; and A Licensing Review for an HNEC.

  13. Studying antimatter

    CERN Multimedia

    CERN. Geneva

    2006-01-01

    Antiparticles are a crucial ingredient of particle physics and cosmology. Almost 80 years after Dirac’s bold prediction and the subsequent discovery of the positron in 1932, antiparticles are still in the spotlight of modern physics. This lecture for non-specialists will start with a theoretical and historical introduction. Why are antiparticles needed? When and how were they discovered? Why is the (CPT) symmetry between particles and antiparticles so fundamental? What is their role in cosmology? The second part will give an overview about the many aspects of antiparticles in experimental physics: their production, their use in colliders; as a probe inside atoms or nuclei; or as an object to study fundamental symmetries. In the third part, the lecture will focus on results and challenges of the “antimatter” programme at the Antiproton Decelerator (AD), with special emphasis on antihydrogen production, trapping and precision measurements.

  14. Treatability studies

    DEFF Research Database (Denmark)

    Bennedsen, Lars Rønn; Studds, Phil

    implementation of the preferred remedial technology.    In stead of selecting a full scale technique solely based on information collated during a literature research it is best practice to supplement the remediation screening phase with laboratory and in situ pilot treatability tests. As well as establishing......The fundamental information that a well-designed treatability study can provide is essential to the success of all remediation systems. Over the past years several new techniques for in situ and on site remediation of contaminated soil and groundwater have been used with varying degrees of success....... Based on the wide selection of different techniques several screening matrices have been developed in order to make it easier to choose the best suited technique for a given situation. However, these matrices only provide an indication of which technology that might be effective and often the assessor...

  15. Systems Studies

    Energy Technology Data Exchange (ETDEWEB)

    Graham, R.L.

    1998-03-17

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity; the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the US. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated BioEnergy Systems (TBS) Activity of TEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the US and the UK. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modeling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from technoeconomic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the US. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review.

  16. Study on

    Directory of Open Access Journals (Sweden)

    Razieh Pourdarbani

    2015-01-01

    Full Text Available In the present study, a machine vision based, online sorting system was developed, the aim being to sort Date fruits (Berhee CV. based at different stages of maturity, namely Khalal, Rotab and Tamar to meet consumers’ demands. The system comprises a conveying unit, illumination and capturing unit, and sorting unit. Physical and mechanical features were extracted from the samples provided, and the detection algorithm was designed accordingly. An index based on color features was defined to detect Date samples. Date fruits were fed on a conveyor belt in a row. When they were at the center of the camera’s field of view, a snapshot was taken, the image was processed immediately and the maturity stage of the Date was determined. When the Date passed the sensor, positioned at the end of the conveyor belt, a signal was sent to the interface circuit and an appropriate actuator, driven by a step motor, was actuated, leading the Date toward an appropriate port. For validation of proposed system performance, entire samples were again sorted by experts visually. Detection rate of the system for Tamar and Khalal was satisfactory. Although the detection rate was insufficient for the Rotab stage, there was no a significant difference between system accuracy and that obtained by the experts. The speed of image processing system was 0.34 s. System capacity was 15.45 kg/h.

  17. Studying toxicity

    Science.gov (United States)

    Elkus, A.; LeBlanc, L.; Kim, C.; Van Beneden, R.; Mayer, G.

    2006-01-01

    With funding from the George Mitchell Center for the Environment at the University of Maine, a team of scientists used a simple laboratory-based sediment resuspension design, and two well-established aquatic toxicology models, fathead minnows (Pimephales promelas) and zebrafish (Danio rerio), to evaluate if resuspension of Penobscot river sediment significantly elevates the toxicity of river water and to provide preliminary information on the types of chemicals likely to desorb during resuspension. The group collected sediments from two sites with known chemical contamination downstream of the Great Works and Veazie dams. The sediments were examined to determine the dynamics of PAH desorption and degradation under different resuspension frequencies. The scientists used clarified water from resuspension experiments for toxicity tests with the water-flea Ceriodaphnia dubia, and other aquatic test organisms to infer toxicity from sediments from northern California rivers. Data from the study will help ascertain whether metals and/or xenoestrogens are present in the desorption water and give insight into possible avenues of sediment remediation.

  18. Insights and participatory actions driven by a socio-hydrogeological approach for groundwater management: the Grombalia Basin case study (Tunisia)

    Science.gov (United States)

    Tringali, C.; Re, V.; Siciliano, G.; Chkir, N.; Tuci, C.; Zouari, K.

    2017-08-01

    Sustainable groundwater management strategies in water-scarce countries need to guide future decision-making processes pragmatically, by simultaneously considering local needs, environmental problems and economic development. The socio-hydrogeological approach named `Bir Al-Nas' has been tested in the Grombalia region (Cap Bon Peninsula, Tunisia), to evaluate the effectiveness of complementing hydrogeochemical and hydrogeological investigations with the social dimension of the issue at stake (which, in this case, is the identification of groundwater pollution sources). Within this approach, the social appraisal, performed through social network analysis and public engagement of water end-users, allowed hydrogeologists to get acquainted with the institutional dimension of local groundwater management, identifying issues, potential gaps (such as weak knowledge transfer among concerned stakeholders), and the key actors likely to support the implementation of the new science-based management practices resulting from the ongoing hydrogeological investigation. Results, hence, go beyond the specific relevance for the Grombaila basin, showing the effectiveness of the proposed approach and the importance of including social assessment in any given hydrogeological research aimed at supporting local development through groundwater protection measures.

  19. Bioconversion of Coal: Hydrologic indicators of the extent of coal biodegradation under different redox conditions and coal maturity, Velenje Basin case study, Slovenia

    Science.gov (United States)

    Kanduč, Tjaša; Grassa, Fausto; Lazar, Jerneja; Jamnikar, Sergej; Zavšek, Simon; McIntosh, Jennifer

    2014-05-01

    Underground mining of coal and coal combustion for energy has significant environmental impacts. In order to reduce greenhouse gas emissions, other lower -carbon energy sources must be utilized. Coalbed methane (CBM) is an important source of relatively low-carbon energy. Approximately 20% of world's coalbed methane is microbial in origin (Bates et al., 2011). Interest in microbial CBM has increased recently due to the possibility of stimulating methanogenesis. Despite increasing interest, the hydrogeochemical conditions and mechanisms for biodegradation of coal and microbial methane production are poorly understood. This project aims to examine geochemical characteristics of coalbed groundwater and coalbed gases in order to constrain biogeochemical processes to better understand the entire process of coal biodegradation of coal to coalbed gases. A better understanding of geochemical processes in CBM areas may potentially lead to sustainable stimulation of microbial methanogenesis at economical rates. Natural analogue studies of carbon dioxide occurring in the subsurface have the potential to yield insights into mechanisms of carbon dioxide storage over geological time scales (Li et al., 2013). In order to explore redox processes related to methanogenesis and determine ideal conditions under which microbial degradation of coal is likely to occur, this study utilizes groundwater and coalbed gas samples from Velenje Basin. Determination of the concentrations of methane, carbondioxide, nitrogen, oxygen, argon was performed with homemade NIER mass spectrometer. Isotopic composition of carbon dioxide, isotopic composition of methane, isotopic composition of deuterium in methane was determined with Europa-Scientific IRMS with an ANCA-TG preparation module and Thermo Delta XP GC-TC/CF-IRMS coupled to a TRACE GC analyzer. Total alkalinity of groundwater was measured by Gran titration. Major cations were analyzed by ICP-OES and anions by IC method. Isotopic composition of

  20. Natural radioactivity and groundwater quality assessment in the northern area of the Western Desert of Egypt

    National Research Council Canada - National Science Library

    Mohamed Yehia; Ashraf Baghdady; Fares M. Howari; Samir Awad; Ahmed Gad

    2017-01-01

    The chemical composition and natural radioactivity of the northern area of the western desert groundwater were determined to evaluate hydrogeochemical facies and assess groundwater quality for different uses...

  1. Prospects and quality indices for groundwater development in Ibadan metropolis, southwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Ajibade, O.M.

    2013-03-01

    Full Text Available An integrated geophysical and hydrogeochemical studies were conducted in part of Ibadan metropolis, Southwestern Nigeria to investigate the groundwater potential and quality for sustainable development. Interpreted results of vertical electrical sounding data revealed three to four geo-electric layers; top soil (22.1-441.4 Ωm, lateritic horizon (402.1-712.2 Ωm, clayey/sandyclay layer (2.95-66.0 Ωm and weathered/fractured bedrock (66.3-1056.7 Ωm. Stacked overburden isopach and basement isoresitivity maps revealed few areas with thick overburden and fractured basement, hence of apparently high groundwater prospect. Hydrogeochemical study indicates that groundwater in the study area is generally fresh, soft- moderately hard, slightly acidic and dominated by Na, Ca, Mg, Cl and HCO3 ions. The dominant hydrochemical facies is Na-Cl type with minor mixed Ca-Na-Cl and Ca-Cl types. Many of the analyzed parameters fall within recommended limits and thus, most of the groundwater in the study area are chemically suitable for drinking. A few however, recorded TDS, pH, NO3, Al, Mg and Cl concentrations above permissible levels, suggesting some concern in terms of potability. The groundwater quality for agricultural purposes was assessed using Sodium absorption ratio, permeability index and electrical conductivity values along with USSL and Wilcox diagrams, all indicating that most of the samples are excellent to good for irrigation.

  2. Scranton 1/sup 0/ x 2/sup 0/ NTMS area: New Jersey, New York, and Pennsylvania. Preliminary basic data report. National Uranium Resource Evaluation Program. Hydrogeochemical and stream sediment reconnaissance

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, R.B.; Tones, P.L.

    1978-11-01

    Stream sediment and stream water samples were collected from small streams at 980 sites for a nominal density of one site per 18 square kilometers in rural areas. Ground water samples were collected at 1251 sites for a nominal density of one site per 13 square kilometers. Neutron activation analysis results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water and surface water. Field measurements and observations are reported for each site. Analytical data and field measurements are presented in tables and maps. Statistical summaries of data and a brief description of results are given. A generalized geologic map and a summary of the geology of the area are included.

  3. Impact of excessive groundwater pumping on rejuvenation processes in the Bandung basin (Indonesia) as determined by hydrogeochemistry and modeling

    Science.gov (United States)

    Taufiq, Ahmad; Hosono, Takahiro; Ide, Kiyoshi; Kagabu, Makoto; Iskandar, Irwan; Effendi, Agus J.; Hutasoit, Lambok M.; Shimada, Jun

    2017-12-01

    In the Bandung basin, Indonesia, excessive groundwater pumping caused by rapid increases in industrialization and population growth has caused subsurface environmental problems, such as excessive groundwater drawdown and land subsidence. In this study, multiple hydrogeochemical techniques and numerical modeling have been applied to evaluate the recharge processes and groundwater age (rejuvenation). Although all the groundwater in the Bandung basin is recharged at the same elevation at the periphery of the basin, the water type and residence time of the shallow and deep groundwater could be clearly differentiated. However, there was significant groundwater drawdown in all the depression areas and there is evidence of groundwater mixing between the shallow and deep groundwater. The groundwater mixing was traced from the high dichlorodifluoromethane (CFC-12) concentrations in some deep groundwater samples and by estimating the rejuvenation ratio (R) in some representative observation wells. The magnitude of CFC-12 concentration, as an indicator of young groundwater, showed a good correlation with R, determined using 14C activity in samples taken between 2008 and 2012. These correlations were confirmed with the estimation of vertical downward flux from shallower to deeper aquifers using numerical modeling. Furthermore, the change in vertical flux is affected by the change in groundwater pumping. Since the 1970s, the vertical flux increased significantly and reached approximately 15% of the total pumping amount during the 2000s, as it compensated the groundwater pumping. This study clearly revealed the processes of groundwater impact caused by excessive groundwater pumping using a combination of hydrogeochemical methods and modeling.

  4. Spring water quality and usability in the Mount Cameroon area revealed by hydrogeochemistry.

    Science.gov (United States)

    Ako, Andrew Ako; Shimada, Jun; Hosono, Takahiro; Kagabu, Makoto; Ayuk, Akoachere Richard; Nkeng, George Elambo; Eyong, Gloria Eneke Takem; Fouepe Takounjou, Alain L

    2012-10-01

    Groundwater is the only reliable water resource for drinking, domestic, and agricultural purposes for the people living in the Mount Cameroon area. Hydrogeochemical and R-mode factor analysis were used to identify hydrogeochemical processes controlling spring water quality and assess its usability for the above uses. Main water types in the study area are Ca-Mg-HCO(3) and Na-HCO(3). This study reveals that three processes are controlling the spring water quality. CO(2)-driven silicate weathering and reverse cation exchange are the most important processes affecting the hydrochemistry of the spring waters. While tropical oceanic monsoon chloride-rich/sulfate-rich rainwater seems to affect spring water chemistry at low-altitude areas, strong correlations exist between major ions, dissolved silica and the altitude of springs. In general, the spring waters are suitable for drinking and domestic uses. Total hardness (TH) values indicate a general softness of the waters, which is linked to the development of cardiovascular diseases. Based on Na %, residual sodium carbonate, sodium adsorption ratio, and the USSL classification, the spring waters are considered suitable for irrigation. Though there is wide spread use of chemical fertilizers and intense urban settlements at the lower flanks of the volcano, anthropogenic activities for now seem to have little impact on the spring water quality.

  5. Mobilisation processes responsible for iron and manganese contamination of groundwater in Central Adriatic Italy.

    Science.gov (United States)

    Palmucci, William; Rusi, Sergio; Di Curzio, Diego

    2016-06-01

    Iron and manganese are two of the most common contaminants that exceed the threshold imposed by international and national legislation. When these contamination occurs in groundwater, the use of the water resource is forbidden for any purposes. Several studies investigated these two metals in groundwater, but research focused in the Central Adriatic area are still lacking. Thus, the objective of this study is to identify the origin of Fe and Mn contamination in groundwater and the hydrogeochemical processes that can enrich aquifers with these metals. This work is based on hydrogeochemical and multivariate statistical analysis of analytical results undertaken on soils and groundwater. Fe and Mn contamination are widespread in the alluvial aquifers, and their distribution is regulated by local conditions (i.e. long residence time, presence of peat or organic-rich fine sediments or anthropic pollution) that control redox processes in the aquifers and favour the mobilisation of these two metals in groundwater. The concentration of iron and manganese identified within soil indicates that the latter are a concrete source of the two metals. Anthropic impact on Fe and Mn contamination of groundwater is not related to agricultural activities, but on the contrary, the contribution of hydrocarbons (e.g. spills) is evident.

  6. An automatic monitoring network installed in Tuscany (Italy for studying possible geochemical precursory phenomena

    Directory of Open Access Journals (Sweden)

    R. Cioni

    2007-06-01

    Full Text Available Since late 2002, a continuous automatic monitoring network (CAMN was designed, built and installed in Tuscany (Italy, in order to investigate and define the geochemical response of the aquifers to the local seismic activity. The purpose of the investigation was to identify eventual earthquake precursors. The CAMN is constituted by two groups of five measurement stations each. A first group has been installed in the Serchio and Magra graben (Garfagnana and Lunigiana Valleys, Northern Tuscany, while the second one, in the area of Mt. Amiata (Southern Tuscany, an extinct volcano. The measured parameters are: T, pH, Eh, EC, dissolved CO2 and CH4. The results of three years of continuous monitoring can be summarised as follows: i the monitoring stations made it possible to detect even small variations of the measured parameters, with respect to equivalent commercial devices; ii acquired data made it possible to identify the groundwater circulation patterns; iii in most locations, the observed trend of the acquired parameters is consistent with the periodic manual sampling results, and confirms the mixture of different water types that the hydrogeochemical model has determined.

    The absence of seismic events with a sufficient energy precluded the possibility to locate anomalies, with the only exception of the Equi Terme site, where an increase in the dissolved CO2 content was observed twelve days before a M=3.7 earthquake occurred at a distance of 3 km north of the monitoring station.

    The CAMN resulted as being a suitable tool in order to investigate the anomalous variations of the physical, physico-chemical and chemical parameters of aquifer systems as earthquake precursors.

  7. Hydrogeology and hydrogeochemistry at a site of strategic importance: the Pareja Limno-reservoir drainage basin (Guadalajara, central Spain)

    Science.gov (United States)

    Molina-Navarro, Eugenio; Sastre-Merlín, Antonio; Vicente, Rosa; Martínez-Pérez, Silvia

    2014-08-01

    A small calcareous basin in central Spain was studied to establish the role of groundwater in the Pareja Limno-reservoir. Limno-reservoirs aim to preserve a constant water level in the riverine zone of large reservoirs to mitigate the impacts arising from their construction. Groundwater flow contribution (mean 60 %) was derived by recharge estimation. In situ measurements (spring discharge, electrical conductivity and sulfate) were undertaken and spring discharge was compared with a drought index. Twenty-eight springs were monitored and three hydrogeological units (HGUs) were defined: a carbonate plateau (HGU1), the underlying aquitard (HGU2), and the gypsum-enriched HGU3. HGU1 is the main aquifer and may play a role in the preservation of the limno-reservoir water level. Hydrogeochemical sampling was conducted and the code PHREEQC used to describe the main geochemical processes. Weathering and dissolution of calcite and gypsum seem to control the hydrogeochemical processes in the basin. Water progresses from Ca2+-HCO3 - in the upper basin to Ca2+-SO4 2- in the lower basin, where HGU3 outcrops. A clear temporal pattern was observed in the limno-reservoir, with salinity decreasing in winter and increasing in summer. This variation was wider at the river outlet, but the mixing of the river discharge with limno-reservoir water buffered it.

  8. Hydrogeochemistry of arsenic pollution in watersheds influenced by gold mining activities in Paracatu (Minas Gerais State, Brazil).

    Science.gov (United States)

    Bidone, Edison; Castilhos, Zuleica; Cesar, Ricardo; Santos, Maria Carla; Sierpe, Ricardo; Ferreira, Marcos

    2016-05-01

    The aim of this study is to evaluate total arsenic (As) concentrations in drinking water (main pathway of human exposure) and its hydrogeochemical controls in the "Morro do Ouro" gold mine region, which is the largest gold mine in Brazil, characterized by gold-arsenopyrite association. Arsenic concentration was generally below the detection limit (LOD 20°, being readily covered by thick phyllites that are poor in As some hundreds of meters away from the mine. Thirty-five percent of As levels in superficial waters (10 μg L(-1), which is the maximum permissible value for human ingestion. The highest concentrations were found nearby mine facilities and old artisanal mining areas surrounding the mine, decreasing downstream. Undisturbed watersheds showed As concentrations close to LOD. Hydrogeochemical data stress the sorption (adsorption and co-precipitation) of As role, mainly by Fe oxyhydroxides, as a geochemical filter that retains As, attenuating its concentration in both superficial and groundwater. Such minerals are abundant in the region oxisols, sediments, and phyllites and may form stable mineral complexes with As under the pH (mostly neutral) and Eh (reduced environment) conditions found in the field. It has been demonstrated that As(III) (more toxic) and As(V) co-exist in the analyzed waters and that As(V) predominates in superficial water.

  9. Geochemical features of the ore-bearing medium in uranium deposits in the Khiagda ore field

    Science.gov (United States)

    Kochkin, B. T.; Solodov, I. N.; Ganina, N. I.; Rekun, M. L.; Tarasov, N. N.; Shugina, G. A.; Shulik, L. S.

    2017-09-01

    The Neogene uranium deposits of the Khiagda ore field (KOF) belong to the paleovalley variety of the hydrogene type and differ from other deposits of this genetic type in the geological and geochemical localization conditions. The contemporary hydrogeochemical setting and microbiological composition of ore-bearing medium are discussed. The redox potential of the medium (Eh is as low as-400 mV) is much lower than those established at other hydrogenic deposits, both ancient Late Mesozoic and young Late Alpine, studied with the same methods in Russia, Uzbekistan, and southern Kazakhstan. The pH of subsurface water (6.86-8.13) differs in significant fluctuations both between neighboring deposits and within individual ore lodes. Hydrogen-forming and denitrifying bacteria are predominant in microbiological populations, whereas sulfate-reducing bacteria are low-active. The consideration of these factors allowed us to describe the mechanism of uranium ore conservation as resulting from the development of the cryolithic zone, which isolates ore lodes from the effect of the external medium. Carbonated water supplied from the basement along fault zones also participates in the formation of the present-day hydrogeochemical setting. Based on the features of the ore-bearing medium, we propose a method of borehole in situ acid leaching to increase the efficiency of mining in the Khiagda ore field.

  10. Geochemical characterisation of pyrite oxidation and environmental problems related to release and transport of metals from a coal washing low-grade waste dump, Shahrood, northeast Iran.

    Science.gov (United States)

    Doulati Ardejani, Faramarz; Jodieri Shokri, Behshad; Moradzadeh, Ali; Shafaei, Seyed Ziadin; Kakaei, Reza

    2011-12-01

    Pyrite oxidation and release of the oxidation products from a low-grade coal waste dump to stream, groundwater and soil was investigated by geochemical and hydrogeochemical techniques at Alborz Sharghi coal washing plant, Shahrood, northeast Iran. Hydrogeochemical analysis of water samples indicates that the metal concentrations in the stream waters were low. Moreover, the pH of the water showed no considerable change. The analysis of the stream water samples shows that except the physical changes, pyrite oxidation process within the coal washing waste dump has not affected the quality of the stream water. Water type was determined to be calcium sulphate. The results of the analysis of groundwater samples indicate that the pH varies from 7.41 to 7.51. The concentrations of the toxic metals were low. The concentration of SO4 is slightly above than its standard concentration in potable water. It seems that the groundwater less affected by the coal washing operation in the study area. Geochemical analysis of the sediment samples shows that Fe concentration decreases gradually downstream the waste dump with pH rising. SO(4) decreases rapidly downstream direction. Copper, Zn and Co concentrations decrease with distance from the waste dump due to a dilution effect by the mixing of uncontaminated sediments. These elements, in particular, Zn are considerably elevated in sediment sample collected at the nearest distance to the waste dump. There is no doubt that such investigations can help to develop an appropriate water remediation plan.

  11. Case Study: Testing with Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman

    2015-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses using case studies to test for knowledge or lessons learned.

  12. Islands, Island Studies, Island Studies Journal

    Directory of Open Access Journals (Sweden)

    Godfrey Baldacchino

    2006-05-01

    Full Text Available Islands are sites of innovative conceptualizations, whether of nature or human enterprise, whether virtual or real. The study of islands on their own terms today enjoys a growing and wide-ranging recognition. This paper celebrates the launch of Island Studies Journal in the context of a long and thrilling tradition of island studies scholarship.

  13. Case Study: Writing a Journal Case Study

    Science.gov (United States)

    Prud'homme-Genereux, Annie

    2016-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue describes incorporating a journal article into the classroom by first converting it into a case study.

  14. Electrophysiology Studies (EPS)

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Electrophysiology Studies (EPS) Updated:Dec 21,2016 What are electrophysiology studies? Electrophysiology studies (EPS) are tests that help doctors ...

  15. Learn about Clinical Studies

    Science.gov (United States)

    ... Glossary of Common Site Terms Learn About Clinical Studies Contents What Is a Clinical Study? Clinical Trials ... Participation Questions to Ask What Is a Clinical Study? A clinical study involves research using human volunteers ( ...

  16. Feasibibility study - cases

    DEFF Research Database (Denmark)

    Lund, Henrik; Hvelplund, Frede Kloster; Sukkumnoed, Decharut

    2004-01-01

    The chapter presents two case studies to show the tools of feasibiliy studies within the context of technological innovation.......The chapter presents two case studies to show the tools of feasibiliy studies within the context of technological innovation....

  17. Drinking Game Studies

    DEFF Research Database (Denmark)

    Debus, Michael S.

    2016-01-01

    The paper examines research on drinking game participation from a game studies ontological perspective, covering definition, classification and problems with the, in the studies implied, underlying ontology of drinking games.......The paper examines research on drinking game participation from a game studies ontological perspective, covering definition, classification and problems with the, in the studies implied, underlying ontology of drinking games....

  18. Physics studies in Europe; a comparative study

    NARCIS (Netherlands)

    Steenstrup, S; dalle Rose, LFD; Jones, WG; Tugulea, L; van Steenwijk, FJ

    What are the differences and similarities between physics studies at different universities across Europe (here the definition of Europe is broad)? How much does a student have to work to obtain a degree in physics? Questions like those prompted EUPEN (European Physics Education Network) to make a

  19. Case study research.

    Science.gov (United States)

    Taylor, Ruth; Thomas-Gregory, Annette

    2015-06-10

    This article describes case study research for nursing and healthcare practice. Case study research offers the researcher an approach by which a phenomenon can be investigated from multiple perspectives within a bounded context, allowing the researcher to provide a 'thick' description of the phenomenon. Although case study research is a flexible approach for the investigation of complex nursing and healthcare issues, it has methodological challenges, often associated with the multiple methods used in individual studies. These are explored through examples of case study research carried out in practice and education settings. An overview of what constitutes 'good' case study research is proposed.

  20. Humanities, Digital Humanities, Media studies, Internet studies

    DEFF Research Database (Denmark)

    Brügger, Niels

    Todays expanding digital landscape constitutes an important research object as well as the research environment for the Humanities at the beginning of the 21st century. Taking this state of affairs as a starting point this inaugural lecture presents a vision for how the digital affects the interp......Todays expanding digital landscape constitutes an important research object as well as the research environment for the Humanities at the beginning of the 21st century. Taking this state of affairs as a starting point this inaugural lecture presents a vision for how the digital affects...... the interplay between four areas which until now to a certain extent have been separated: Traditional Hu- manities, Digital Humanities, Media studies, and Internet studies. The vision is followed by an outline of how it can be unfolded in concrete activities, in the form of research projects, research...

  1. Study deep geothermal energy; Studie dypgeotermisk energi

    Energy Technology Data Exchange (ETDEWEB)

    Havellen, Vidar; Eri, Lars Sigurd; Andersen, Andreas; Tuttle, Kevin J.; Ruden, Dorottya Bartucz; Ruden, Fridtjof; Rigler, Balazs; Pascal, Christophe; Larsen, Bjoern Tore

    2012-07-01

    The study aims to analyze the potential energy with current technology, challenges, issues and opportunities for deep geothermal energy using quantitative analysis. It should especially be made to identify and investigate critical connections between geothermal potential, the size of the heating requirements and technical solutions. Examples of critical relationships may be acceptable cost of technology in relation to heating, local geothermal gradient / drilling depth / temperature levels and profitability. (eb)

  2. Water quality assessment of the Asata River catchment area in Enugu Metropolis, Southeast Nigeria

    Science.gov (United States)

    Osinowo, Olawale Olakunle

    2016-09-01

    Hydrogeochemical mapping of the Asata River Catchment area in the Enugu metropolis, southeast Nigeria was carried out in order to assess the quality of the surface and groundwater and based on the analyses of the hydrogeochemical data, establish the level of chemical contaminations which inhibit the availability of potable water in the area. Forty (40) water samples comprising five (5) springs, nineteen (19) surface (streams/rivers) and sixteen (16) groundwater (well/borehole) samples were collected and analysed for the presence and degree of contamination of nine (9) major chemical contaminants. Hydrochemical analyses indicate that Electrical Conductivity (EC) which has a linear relationship with Total Dissolved Solid (TDS) ranges between 015 and 887 μS/cm, pH between 4.4 and 8.3, nitrate (NO3-) ranges between 40 and 130 mg/l and chloride (Cl-) between 7 and 130 mg/l. The concentrations of the dissolved chemical constituents defined the pollution trend and the rate of dispersion of contaminants. The degree of contaminants followed a simple trend, where the level of contamination of the dissolved chemical constituents is least in sampled spring water, with measured chemical constituents of EC, pH, NO3- and Cl- range from 15 to 354 μS/cm; 6.4-6.5; 4.0-70 mg/l and 8-36 mg/l, respectively. However, the value of the measured chemical constituent of EC, pH, NO3- and Cl- gradually increases down the stream in both the surface (63-354 μS/cm; 4.5-7.7; 7.1-110 mg/l; 8-41 mg/l) and groundwater (56-531 μS/cm; 4.5-7.5; 40-130 mg/l; 7-130 mg/l), respectively. Noticeable peaks in contamination levels characterised sections of the study area where human population or their activities is highest. The result of the hydrogeochemical mapping indicate that Enugu coal mine operation, the industrial activities, fertilizer applied to plants cultivated on river banks and domestic human wastes which are indiscriminately dumped along river channels are the major sources of chemical

  3. Cracking the Case (Study).

    Science.gov (United States)

    DeCarolis, Sabrina

    1995-01-01

    Discusses how technical communicators can get their clients to participate in case studies (for use in marketing the technical communicator's services) by analyzing the case study strategy, selecting appropriate clients, understanding their concerns, and developing a professional presentation. (RS)

  4. Post-Approval Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CDRH Post-Approval Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated as a condition of approval of a...

  5. The People Study

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The authors of this study are participants in a National Science Foundation ( NSF) supported grant entitled "Mathematical Studies in Modeling at Mount St. Mary's...

  6. Advances in Sleep Studies

    Science.gov (United States)

    ... page please turn JavaScript on. Feature: Sleep Disorders Advances in Sleep Studies Past Issues / Summer 2015 Table ... Disorders / Tips for Getting A Good Night's Sleep / Advances In Sleep Studies Summer 2015 Issue: Volume 10 ...

  7. Chemical Industry Bandwidth Study

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-12-01

    The Chemical Bandwidth Study provides a snapshot of potentially recoverable energy losses during chemical manufacturing. The advantage of this study is the use of "exergy" analysis as a tool for pinpointing inefficiencies.

  8. 522 Postmarket Surveillance Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The 522 Postmarket Surveillance Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated under section 522 of the...

  9. What Are Sleep Studies?

    Science.gov (United States)

    ... Sleep Studies Related Topics CPAP Narcolepsy Sleep Apnea Sleep Deprivation and Deficiency Send a link to NHLBI to ... away after they are removed. Your doctor will review your sleep study test results and develop a treatment plan ...

  10. Air Manganese Study

    Science.gov (United States)

    In November 2011 US EPA researchers conducted a health study of airborne manganese exposure in East Liverpool, Ohio. This Web site discusses preliminary results of the study and provides background and other related information.

  11. Case Study Teaching

    Science.gov (United States)

    Herreid, Clyde Freeman

    2011-01-01

    This chapter describes the history of case study teaching, types of cases, and experimental data supporting their effectiveness. It also describes a model for comparing the efficacy of the various case study methods. (Contains 1 figure.)

  12. Productivity Studies in Greenland

    DEFF Research Database (Denmark)

    Winther, Gorm

    2005-01-01

    Presentation of research project 'Productitivity Studies in Greenland', methodologies, work place relations, employee participation.......Presentation of research project 'Productitivity Studies in Greenland', methodologies, work place relations, employee participation....

  13. The Study of Algae

    Science.gov (United States)

    Rushforth, Samuel R.

    1977-01-01

    Included in this introduction to the study of algae are drawings of commonly encountered freshwater algae, a summary of the importance of algae, descriptions of the seven major groups of algae, and techniques for collection and study of algae. (CS)

  14. Statewide shoulders study.

    Science.gov (United States)

    2015-08-01

    With the ultimate purpose of enhancing safety and improving mobility, the Statewide Shoulders Study was initiated to : develop a prioritized list of candidate locations for shoulder improvements. The need for this study stems directly from : ADOTs...

  15. GASP. CONTAMINATION STUDY

    Science.gov (United States)

    LAUNCHING SITES, MEASUREMENT, MATHEMATICAL MODELS, TEST METHODS, TRACER STUDIES, RADIOACTIVE CONTAMINATION , INSTRUMENTATION, STATISTICAL ANALYSIS, RADIATION HAZARDS, UNDERWATER EXPLOSIONS, RADIOCHEMISTRY.

  16. Chaitanya case study

    International Development Research Centre (IDRC) Digital Library (Canada)

    lremy

    “Those Who Dream Make a Difference”. Some of Kalpana's written work includes, a study titled Sexual Harassment in. University Campus, published in the TISS Journal; a national level study on Federations coordinated by Sa_dhan;. Networking of SHGs - a case study of Devoshi village, published in Swaskhati journal; etc ...

  17. Social Psychoanalytic Disability Studies

    Science.gov (United States)

    Goodley, Dan

    2011-01-01

    This paper explores connections and tensions between psychoanalysis and disability studies. The first part of the paper considers contemporaneous engagements with the psyche by a number of disability studies writers. These scholars have remained accountable to a politicised disability studies but have pushed for critical encounters with the…

  18. Cave Water Studies.

    Science.gov (United States)

    O'Keefe, Elizabeth S.

    1996-01-01

    Describes a comparative study project where seventh grade students tested water samples from 10 cave sites that had been tested 24 years ago in a study that had attempted to determine if pollution in the environment had reached cave water. Discusses lab skills and some results of the study. (JRH)

  19. Selling the Social Studies.

    Science.gov (United States)

    Girod, Gerald R.; Harmon, Gerald R.

    1987-01-01

    Maintains school-aged children would prefer not to study social studies. Presents several strategies to help encourage positive attitudes. Strategies include persuasion, reinforcement, enthusiasm, personalized contact. Stresses that negative attitudes must be changed in order for social studies to achieve its fundamental citizenship goals. (BR)

  20. Studying Engineering Practice

    DEFF Research Database (Denmark)

    Buch, Anders

    2015-01-01

    The study of engineering practices has been the focus of Engineering Studies over the last three decades. Theses studies have used ethnographic and grounded methods in order to investigate engineering practices as they unfold in natural settings - in workplaces and engineering education. However......, engineering studies have not given much attention to conceptually clarifying what should be understood by 'engineering practices' and more precisely account for the composition and organization of the entities and phenomena that make up the practices. This chapter investigates and discusses how a 'practice...... will draw out some methodological consequences and discuss the ramifications of a practice theoretical approach for Engineering Studies....

  1. Sedimentology, hydrogeology and hydrogeochemistry of Machile Basin, Zambia

    DEFF Research Database (Denmark)

    Banda, Kawawa Eddy

    An important environmental problem in arid to semi-arid regions of the world is salinisation of water resources. Moreover, most of these regions are inhabited by poor communities in developing countries, with limited or no financial resources to develop suitable alternatives to meet their basic....... Water resources practioners in arid and semi-arid regions accept that future development of groundwater resources depends largely on the degree and rate of salinisation. This PhD study focuses on investigating the sedimentological and hydro-geochemical conditions that have shaped the groundwater...... environment in Western Zambia to the present hydrogeology, in particular the origin and dynamics of groundwater salinity. The case study is the Machile Basin of south-western Zambia, a semi-arid region on the northern extension of a desiccated lake system – Palaeo-lake Makgadikgadi (PLM), southern Africa. PLM...

  2. Event studies in Turkey

    Directory of Open Access Journals (Sweden)

    Ulkem Basdas

    2014-09-01

    Full Text Available The primary goal of this paper is to review the event studies conducted for Turkey to in order to identify the common components in their designs. This paper contributes to the existing literature by reviewing all event studies for Turkey for the first time, but more importantly; this review leads to the upcoming event studies on Turkey by highlighting main components of a proper design. Based on the review of 75 studies, it is observed that event studies generally choose BIST-100 (formerly, ISE-100 market index and market adjusted returns with the parametric tests. In general, the studies prefer to rely on one type of model to calculate abnormal returns without discussing the selection of the underlying model. Especially for the event studies focusing on the impact of political events or macroeconomic announcements in Turkey, there is a risk of clustering due to the application of same event date for all observations.

  3. Advanced Clothing Studies

    Science.gov (United States)

    Orndoff, Evelyne; Poritz, Darwin

    2014-01-01

    All human space missions require significant logistical mass and volume that add an unprecedented burden on longduration missions beyond low-Earth orbit. For these missions with limited cleaning resources, a new wardrobe must be developed to reduce this logistical burden by reducing clothing mass and extending clothing wear. The present studies have been undertaken, for the first time, to measure length of wear and to assess the acceptance of such extended wear. Garments in these studies are commercially available exercise T-shirts and shorts, routine-wear T-shirts, and longsleeved pullover shirts. Fabric composition (cotton, polyester, light-weight, superfine Merino wool, modacrylic, cotton/rayon, polyester/Cocona, modacrylic/Xstatic, modacrylic/rayon, modacrylic/lyocell/aramid), construction (open knit, tight knit, open weave, tight weave), and finishing treatment (none, quaternary ammonium salt) are the independent variables. Eleven studies are reported here: five studies of exercise T-shirts, three of exercise shorts, two of routine wear Tshirts, and one of shirts used as sleep-wear. All studies are conducted in a climate-controlled environment, similar to a space vehicle's. For exercise clothing, study participants wear the garments during aerobic exercise. For routine wear clothing, study participants wear the T-shirts daily in an office or laboratory. Daily questionnaires collected data on ordinal preferences of nine sensory elements and on reason for retiring a used garment. Study 1 compares knitted cotton, polyester, and Merino exercise T-shirts (61 participants), study 2, knitted polyester, modacrylic, and polyester/Cocona exercise T-shirts (40 participants), study 3, cotton and polyester exercise shorts, knitted and woven (70 participants), all three using factorial experimental designs with and without a finishing treatment, conducted at the Johnson Space Center, sharing study participants. Study 4 compares knitted polyester and ZQ Merino exercise T

  4. Investigation research on the evaluation of a coupled thermo-hydro-mechanical-chemical phenomena. Result report

    Energy Technology Data Exchange (ETDEWEB)

    Chijimatsu, Masakazu; Amemiya, Kiyoshi; Shiozaki, Isao [Hazama Corp., Tokyo (Japan); Neyama, Atsushi; Iwata, Hiroshi; Nakagawa, Koichi [Computer Software Development Co.Ltd. (Japan); Ishihara, Yoshinao; Sagawa, Hiroshi [Mitsubishi Heavy Industries Ltd., Tokyo (Japan)

    2002-02-01

    In order to realize a coupling analysis in the near field of the geological disposal system, this study has been studied on the addition of the mass transport model to the coupled thermo-hydro-mechanical analysis code (THAMES) and preliminary coupling analysis by using development environmental tool (Diffpack) for numerical analysis. (1) In order to prepare the strategy on the addition of the mass transport model to the coupled thermo-hydro-mechanical analysis code (THAMES), we have studied on the requirement of THAMES-Transport and methodology of coupling analysis. After that we set out modification plan by the Eulerian-Lagrangian (EL) method. (2) Based on the document of modification plan, we have done addition of the mass transport model to the coupled thermo-hydro-mechanical analysis code (THAMES) and carried out verification analysis in order to confirm on the accuracy of THAMES-Transport. (3) In order to understand on the behavior of NaCl in the porewater under the coupled thermo-hydro-mechanical phenomena in the HLW engineered barrier system, we have calculated coupling phenomenon by using THAMES-Transport. Transportation and concentration phenomena of NaCl are calculated but precipitation of NaCl is not occurred under the analysis conditions in this report. (4) In order to confirm about feasibility of coupling analysis under the development environmental tool (Diffpack) for numerical analysis, we have carried out on the design work and writing program of the preliminary coupling system. In this study, we have adopted existing transport model (HYDROGEOCHEM) and geochemical model (phreeqe 60) for preliminary coupling system. (5) In order to confirm program correctness of preliminary coupling system, we have carried out benchmarking analysis by using existing reactive-transport analysis code (HYDROGEOCHEM). (6) We have been prepared short-range development plan based on through the modification study of THAMES and writing program of the preliminary coupling

  5. Investigation research on the evaluation of a coupled thermo-hydro-mechanical-chemical phenomena. Outline report

    Energy Technology Data Exchange (ETDEWEB)

    Chijimatsu, Masakazu; Amemiya, Kiyoshi [Hazama Corp., Tokyo (Japan); Neyama, Atsushi; Iwata, Hiroshi; Nakagawa, Koichi [Computer Software Development Co., Ltd., Tokyo (Japan); Ishihara, Yoshinao; Shiozaki, Isao; Sagawa, Hiroshi [Mitsubishi Heavy Industries, LTD., Tokyo (Japan)

    2002-02-01

    In order to realize a coupling analysis in the near field of the geological disposal system, this study has been studied on the addition of the mass transport model to the coupled thermo-hydro-mechanical analysis code (THAMES) and preliminary coupling analysis by using development environmental tool (Diffpack) for numerical analysis. (1) In order to prepare the strategy on the addition of the mass transport model to the coupled thermo-hydro-mechanical analysis code (THAMES), we have studied on the requirement of THAMES-Transport and methodology of coupling analysis. After that we set out modification plan by the Eulerian-Lagrangian (EL) method. (2) Based on the document of modification plan, we have done addition of the mass transport model to the coupled thermo-hydro-mechanical analysis code (THAMES) and carried out verification analysis in order to confirm on the accuracy of THAMES-Transport. (3) In order to understand on the behavior of NaCl in the porewater under the coupled thermo-hydro-mechanical phenomena in the HLW engineered barrier system, we have calculated coupling phenomenon by using THAMES-Transport. Transportation and concentration phenomena of NaCl are calculated but precipitation of NaCl is not occurred under the analysis conditions in this report. (4) In order to confirm about feasibility of coupling analysis under the development environmental tool (Diffpack) for numerical analysis, we have carried out on the design work and writing program of the preliminary coupling system. In this study, we have adopted existing transport model (HYDROGEOCHEM) and geochemical model (phreeqe60) for preliminary coupling system. (5) In order to confirm program correctness of preliminary coupling system, we have carried out benchmarking analysis by using existing reactive-transport analysis code (HYDROGEOCHEM). (6) We have been prepared short-range development plan based on through the modification study of THAMES and writing program of the preliminary coupling

  6. The case study approach

    Science.gov (United States)

    2011-01-01

    The case study approach allows in-depth, multi-faceted explorations of complex issues in their real-life settings. The value of the case study approach is well recognised in the fields of business, law and policy, but somewhat less so in health services research. Based on our experiences of conducting several health-related case studies, we reflect on the different types of case study design, the specific research questions this approach can help answer, the data sources that tend to be used, and the particular advantages and disadvantages of employing this methodological approach. The paper concludes with key pointers to aid those designing and appraising proposals for conducting case study research, and a checklist to help readers assess the quality of case study reports. PMID:21707982

  7. The CAIRO4 study

    DEFF Research Database (Denmark)

    't Lam-Boer, Jorine; Mol, Linda; Verhoef, Cornelis

    2015-01-01

    stages of the disease. We here propose a randomized trial in order to demonstrate that resection of the primary tumour improves overall survival. METHODS/DESIGN: The CAIRO4 study is a multicentre, randomized, phase III study of the Dutch Colorectal Cancer Group (DCCG). Patients with synchronous...... objective of this study is to determine the clinical benefit in terms of overall survival of initial resection of the primary tumour. Secondary endpoints include progression free survival, surgical morbidity, quality of life and the number of patients requiring resection of the primary tumour in the control...... arm. DISCUSSION: The CAIRO4 study is a multicentre, randomized, phase III study that will assess the benefit of resection of the primary tumour in patients with synchronous metastatic CRC. TRIAL REGISTRATION: The CAIRO4 study is registered at clinicaltrials.gov (NCT01606098)....

  8. The CAIRO4 study

    DEFF Research Database (Denmark)

    de Wilt, Johannes H W; Verhoef, Cornelis; Punt, Cornelis J A

    2016-01-01

    stages of the disease. We here propose a randomized trial in order to demonstrate that resection of the primary tumour improves overall survival. METHODS/DESIGN: The CAIRO4 study is a multicentre, randomized, phase III study of the Dutch Colorectal Cancer Group (DCCG). Patients with synchronous...... objective of this study is to determine the clinical benefit in terms of overall survival of initial resection of the primary tumour. Secondary endpoints include progression free survival, surgical morbidity, quality of life and the number of patients requiring resection of the primary tumour in the control...... arm. DISCUSSION: The CAIRO4 study is a multicentre, randomized, phase III study that will assess the benefit of resection of the primary tumour in patients with synchronous metastatic CRC. TRIAL REGISTRATION: The CAIRO4 study is registered at clinicaltrials.gov (NCT01606098)....

  9. Individual Water Purifier Study

    Science.gov (United States)

    2007-11-01

    study participants (Appendix A) who contributed their time and expertise to the analysis described in this report. 5 Blank 6 CONTENTS 1. INTRODUCTION ...and Weaknesses of Individual Devices ....................... 44 8 INDIVIDUAL WATER PURIFIER STUDY 1. INTRODUCTION This study was performed to evaluate...Data were gathered on each device and documented in a database. A Multi-Criteria Decision Model ( MCDM ) was developed, and a panel of experts assessed

  10. Salary Equity Study 2010

    OpenAIRE

    Virginia Tech. Office of Institutional Research and Effectiveness

    2010-01-01

    As part of the ongoing AdvanceVT program, Virginia Tech conducts salary equity studies on a regular basis to determine sources of variation in faculty salaries. This year’s equity study, conducted by the Office of Institutional Research and Effectiveness, analyzed salary data from December 2009 to reflect a timeframe similar to the previous studies. Considerable attention was paid to race/ethnicity as well as gender as factors in explaining variation in salaries. As in the past, the analysis ...

  11. A synthesis of hydrochemistry with an integrated conceptual model for groundwater in the Hexi Corridor, northwestern China

    Science.gov (United States)

    Wang, Liheng; Dong, Yanhui; Xu, Zhifang

    2017-09-01

    Although many studies have investigated the recharge and evolution of groundwater in the Hexi Corridor, northwestern (NW) China, they describe individual sites such as Jinchang, Jiuquan, Dunhuang, and others. Considering the similarity of these sites, a systematic review of the entire Hexi Corridor is lacking. This paper compares and summarizes previous studies in the Hexi Corridor to provide a regional perspective of the isotopic characteristics and hydrochemical composition of groundwater. In unconfined aquifers, groundwater is recharged by snow and ice melt water from the Qilian Mountains; local precipitation can be neglected. Therefore, the groundwater belongs to a unique hydrological cycle model in the Hexi Corridor, referred to as snow and ice melt water-groundwater system. The dominant anion species changes from HCO3- in front of the mountains to SO42- in the middle basin and Cl- at the basin boundary along the groundwater flow direction, and TDS increases gradually owing to evaporation. A major hydrogeochemical process is the dissolution of minerals from the aquifer in the recharge area changing to cation exchange reactions in the discharge area. Confined groundwater was recharged mainly in the late Pleistocene and middle Holocene at colder temperatures than those of modern times; thus, it is non-renewable. In addition to dissolution, the hydrochemical composition of confined groundwater is also affected by cation exchange reactions. The hydrogeochemical categories of the confined groundwater are simple and stable. In the present study, a conceptual model is established on the basis of the analyses presented, which has important implications for water resource management in the Hexi Corridor. The inter-basin water allocation program should continue in order to achieve optimal utilization of water resources, but groundwater exploitation should be limited as much as possible. Additionally, on the basis of the review and integration of previous research, the

  12. Study Groups in Denmark

    DEFF Research Database (Denmark)

    Hjorth, Poul G.

    2007-01-01

    Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions.......Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions....

  13. Information society studies

    CERN Document Server

    Duff, Alistair S

    2013-01-01

    We are often told that we are ""living in an information society"" or that we are ""information workers."" But what exactly do these claims mean, and how might they be verified? In this important methodological study, Alistair S. Duff cuts through the rhetoric to get to the bottom of the ""information society thesis."" Wide-ranging in coverage, this study will be of interest to scholars in information science, communication and media studies and social theory. It is a key text for the newly-unified specialism of information society studies, and an indispensable guide to the future of this disc

  14. Project management case studies

    CERN Document Server

    Kerzner, Harold R

    2013-01-01

    A new edition of the most popular book of project management case studies, expanded to include more than 100 cases plus a ""super case"" on the Iridium Project Case studies are an important part of project management education and training. This Fourth Edition of Harold Kerzner''s Project Management Case Studies features a number of new cases covering value measurement in project management. Also included is the well-received ""super case,"" which covers all aspects of project management and may be used as a capstone for a course. This new edition:Contains 100-plus case studies drawn from re

  15. Lesson study i Danmark?

    DEFF Research Database (Denmark)

    Mogensen, Arne

    2009-01-01

    Der beskrives et japansk lesson study forløb, og det diskuteres i hvilket omfang, de gode japanske erfaringer kan overføres til dansk matematikundervisning.......Der beskrives et japansk lesson study forløb, og det diskuteres i hvilket omfang, de gode japanske erfaringer kan overføres til dansk matematikundervisning....

  16. Missouri airport investment study

    Science.gov (United States)

    The studys purpose is to provide MoDOT with insight to the potential ROI for airport : investments in terms of economic development. To do so, this study addresses two central : objectives: first, an approach to evaluate airport investments; and s...

  17. Fall 1984 Retention Study.

    Science.gov (United States)

    Peralta Community Coll. District, Oakland, CA. Office of Research, Planning and Development.

    A study was conducted of the retention patterns of students enrolled in the Peralta Community College District (PCCD) in fall 1984 using college reports on withdrawals and grade distributions. The study focused on successful retention (i.e., all students who received a passing grade) and on total retention (i.e., all students who received any…

  18. Differentiating Study Guides

    Science.gov (United States)

    Conderman, Greg; Hedin, Laura

    2017-01-01

    Study guides are a popular and frequently student-requested instructional support developed primarily by upper elementary, middle, and high school teachers to help students navigate through a course of study. With the increase of the number of learners with diverse needs in general education classrooms, teachers need to be mindful of various ways…

  19. Archives: African Studies Monographs

    African Journals Online (AJOL)

    Archives: African Studies Monographs. Journal Home > Archives: African Studies Monographs. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. 1 - 5 of 5 Items. 2007. Vol 8 (2007) ...

  20. WHY STUDY PORTUGUESE.

    Science.gov (United States)

    ANDREWS, NORWOOD, JR.

    REASONS ARE ADVANCED FOR STUDYING PORTUGUESE, BASED ON THE IMPORTANCE OF THE PORTUGUESE-SPEAKING WORLD, ESPECIALLY BRAZIL, TO THE UNITED STATES. DISTINGUISHED PEOPLE IN GOVERNMENT, BUSINESS, AND EDUCATION NOT ONLY TESTIFY TO THE NEED FOR PEOPLE TO LEARN THE LANGUAGE BUT ALSO NOTE THE ADVANTAGES OF SUCH STUDY. LANGUAGE STUDENTS ARE ADVISED THAT…

  1. Pacific Studies: Quo Vadis?

    Directory of Open Access Journals (Sweden)

    Anne Holden Rønning

    2014-02-01

    Full Text Available Looking back to the past this paper discusses why Pacific studies and in particular Australasian studies became an area of interest in tertiary education in Europe. What subject areas initiated these studies, and how do past legacies shape the present? With cutbacks in higher education over the past two decades the future of interdisciplinary studies and the humanities looks bleak. At the same time due to global business and increased political communication across borders there is a vibrant interest in and need for such studies among businesses and students. For most Europeans the literature of settler countries, with their European legacy, makes access to ways of thought and culture easier than studies of countries with other mythological backgrounds. In today’s multicultural environment such studies can provide knowledge for an understanding of other cultures and increase tolerance of the ‘other’. Area studies have relevance to our situation in Europe with increased migrancy, not least as a result of Schengen and EU regulations.

  2. Journal of Cultural Studies

    African Journals Online (AJOL)

    Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. Journal Homepage Image. The Journal of Cultural Studies was established in 1999 as an independent tool for research development in Africa. It is published by the Nigerian Group for the Study of African Cultures (NIGSAC), a non-profit ...

  3. Interagency Depainting Study Status

    Science.gov (United States)

    Clark-Ingram, Marceia; Cook, Beth

    1999-01-01

    This document discusses coating removal in general. Sections of this presentation include: regulatory background, the initial parameters of the study, the current parameters of the study, stages in each sequence, preparation of the test specimen, material evaluation testing, chemical stripping, CO2 blasting, Flashjet coating removal, plastic media blasting, sodium bicarbonate wet stripping, water stripping, and wheat starch stripping.

  4. CDC's Cervical Cancer Study

    Science.gov (United States)

    ... National Cancer Conference Stay Informed CDC’s Cervical Cancer Study Language: English (US) Español (Spanish) Recommend on Facebook Tweet Share ... low-income, underserved women: providing insights into management strategies. ... a pilot study in U.S. Federally Qualified Health Centers. Vaccine 2014; ...

  5. Intrapreneurship - An International Study

    NARCIS (Netherlands)

    Bosma, N.S.; Stam, E.; Wennekers, A.R.M.

    2010-01-01

    This paper presents the first results of a novel international comparative study of intrapreneurship, i.e., employees developing new business activities for their employer. This study is based on an exploratory investigation in the framework of the Global Entrepreneurship Monitor 2008, in which

  6. French Studies: A Bibliography.

    Science.gov (United States)

    Markey, William L., Comp.

    A bibliography of materials relating to French language and area studies includes citations of bibliographies, books, articles, and general and specialized reference materials in French and English in these categories: general reference guides; guides to French studies; style manuals; research methodology and handbooks; library resources;…

  7. Studies of Personality Disorders

    DEFF Research Database (Denmark)

    Ronningstam, Elsa; Simonsen, Erik; Oldham, John M

    2014-01-01

    The past 25 years have shown major advances in the studies of personality disorders. This collaborative article by the presidents, past and present, of ISSPD reflects on the progress within several significant areas of studies, i.e., assessment, neuroscience, treatment, prevention, advocacy...

  8. A descriptive study

    African Journals Online (AJOL)

    Complementary medicine use among Moroccan patients with cancer: A descriptive study. ... Complementary medicine must benefit, as well as conventional medicine, from scientific studies to evaluate potential benefits, toxicity and interactions with the conventional treatment to enable the oncologist better inform his patients ...

  9. Studying Human Origins

    NARCIS (Netherlands)

    Corbey, Raymond; Roebroeks, Wil

    2001-01-01

    This history of human origin studies covers a wide range of disciplines. This important new study analyses a number of key episodes from palaeolithic archaeology, palaeoanthropology, primatology and evolutionary theory in terms of various ideas on how one should go about such reconstructions and

  10. 451 Case studies Cardiac

    African Journals Online (AJOL)

    Marinda

    There appears to be a general agreement that 2% lignocaine with 1:200,000 epinephrine should be used whenever possible specially while using volatile anaesthetics like halothane. Various studies were done comparing varying doses of epinephrine in combination with local anaesthetics and studying their effects.

  11. SASPEN Case Study

    African Journals Online (AJOL)

    Correspondence to: Ms A Prinsloo, e-mail: annettep@ananzi.co.za. SASPEN Case Study. This case study was presented and discussed at the recent SASPEN 2010 Congress by Prof O Goulet, University of Paris Descartes. The summarised discussion of the proceedings was prepared by Annette Prinsloo. Patient's course.

  12. Memetics and Translation Studies

    OpenAIRE

    Andrew, Chesterman

    2000-01-01

    Translation Studies is a branch of memetics. This is a claim, a hypothesis. More specifically, it is an interpretive hypothesis: I claim that Translation Studies can be thus interpreted, and that this is a useful thing to do because it offers a new and beneficial way of understanding translation.

  13. Theorizing Iberian Studies

    Science.gov (United States)

    Newcomb, Robert Patrick

    2015-01-01

    A growing number of scholars invested in Iberian Studies are asking how peninsular literary and cultural studies might be reimagined, and reinvigorated, by placing the Spanish and Portuguese canons into critical dialogue with each other, and with Galician, Catalan, Basque/Euskadi, and Latin American and North African immigrant writers, cultural…

  14. American Studies in Transition

    DEFF Research Database (Denmark)

    Nye, David

    Papers first given at a conference the previous year in Fåborg, Denmark, with a dual focus on 20th century America and new methods in American Studies.......Papers first given at a conference the previous year in Fåborg, Denmark, with a dual focus on 20th century America and new methods in American Studies....

  15. X-ray CT-Derived Soil Characteristics Explain Varying Air, Water, and Solute Transport Properties across a Loamy Field

    DEFF Research Database (Denmark)

    Paradelo Pérez, Marcos; Katuwal, Sheela; Møldrup, Per

    2016-01-01

    The characterization of soil pore space geometry is important for explaining fluxes of air, water, and solutes through soil and understanding soil hydrogeochemical functions. X-ray computed tomography (CT) can be applied for this characterization, and in this study CT-derived parameters were used...... to explain water, air, and solute transport through soil. Forty-five soil columns (20 by 20 cm) were collected from an agricultural field in Estrup, Denmark, and subsequently scanned using a medical CT scanner. Nonreactive tracer leaching experiments were performed in the laboratory along with measurements...... of air permeability (Ka) and saturated hydraulic conductivity (Ksat). The CT number of the matrix (CTmatrix), which represents the moist bulk density of the soil matrix, was obtained from the CT scans as the average CT number of the voxels in the grayscale image excluding macropores and stones...

  16. Des analogues naturels de sites de stockage de déchets nucléaires vieux de 2 milliards d'années : les réacteurs de fission nucléaire naturels du Gabon (Afrique)

    Science.gov (United States)

    Gauthier-Lafaye, François

    2002-10-01

    Two billion years ago, the increase of oxygen in atmosphere and the high 235U/ 238U uranium ratio (>3%) made possible the occurrence of natural nuclear reactors on Earth. These reactors are considered to be a good natural analogue for nuclear waste disposal. Their preservation during such a long period of time is mainly due to the geological stability of the site, the occurrence of clays surrounding the reactors and acting as an impermeable shield, and the occurrence of organic matter that maintained the environment in reducing conditions, favourable for the stability of uraninite. Hydrogeochemical studies and modelling have shown the complexity of the geochemical system at Oklo and Bangombé (Gabon) and the lack of precise data about uranium and fission products retention and migration mechanisms in geological environments. To cite this article: F. Gauthier-Lafaye, C. R. Physique 3 (2002) 839-849.

  17. Application of discriminant analysis and generalized distance measures to uranium exploration

    Energy Technology Data Exchange (ETDEWEB)

    Beauchamp, J.J.; Begovich, C.L.; Kane, V.E.; Wolf, D.A.

    1979-10-01

    The National Uranium Resource Evaluation (NURE) Project has as its goal estimation of the nation's uranium resources. It is possible to use discriminant analysis methods on hydrogeochemical data collected in the NURE Program to aid in formulating geochemical models which can be used to identify the anomalous regions necessary for resource estimation. Discriminant analysis methods have been applied to data from the Plainview, Texas Quadrangle which has approximately 850 groundwater samples with more than 40 quantitative measurements per sample. Discriminant analysis topics involving estimation of misclassification probabilities, variable selection, and robust discrimination are applied. A method using generalized distance measures is given which enables assigning samples to a background population or a mineralized population whose parameters were estimated from separate studies. Each topic is related to its relevance in identifying areas of possible interest to uranium exploration.

  18. Reactive transport modeling of trichloroethene treatment with declining reactivity of iron.

    Science.gov (United States)

    Jeen, Sung-Wook; Mayer, K Ulrich; Gillham, Robert W; Blowes, David W

    2007-02-15

    Evolving reactivity of iron, resulting from precipitation of secondary minerals within iron permeable reactive barriers (PRBs), was included in a reactive transport model for trichloroethene (TCE) treatment. The accumulation of secondary minerals and reactivity loss were coupled using an empirically derived relationship that was incorporated into an existing multicomponent reactive transport code (MIN3P) by modifying the kinetic expressions. The simulation results were compared to the observations from long-term column experiments, which were designed to assess the effects of carbonate mineral formation on the performance of iron for TCE treatment. The model successfully reproduced the evolution of iron reactivity and the dynamic changes in geochemical conditions and contaminant treatment. Predictions under various hydrogeochemical conditions showed that TCE would be treated effectively for an extended period of time without a significant loss of permeability. Although there are improvements yet to be made, this study provides a significant advance in our ability to predict long-term performance of iron PRBs.

  19. Interaction of Rahaliya-Ekhedhur groundwater with the aquifer rock, West Razzaza Lake, Central Iraq

    Science.gov (United States)

    Al-Dabbas, Moutaz A.

    2017-10-01

    The groundwater of Dammam aquifer in Rahaliya-Ekhedhur area, West Razzaza, Iraq, was studied to identify the main hydrogeochemical processes and the groundwater-rock interaction. The results indicated that Na+ and SO4 2- are the dominant ions in the groundwater. The average contribution of cations in the aquifer is Na+ + K+ (24.7 %), Ca2+ (13.9 %), and Mg2+ (11.4 %), while anions contribution is SO4 2- (23.0 %), Cl- (20.7 %), and HCO3 - (6.3 %). The groundwater characterized by neutral to slightly alkaline hard water, excessively mineralized, and slightly brackish water type. Rock-water interaction processes are identified to include dissolution of carbonates, sulfates, halite, and clay minerals, leaching, and cation exchanges, with little impact of evaporation.

  20. Critical Digital Tourism Studies

    DEFF Research Database (Denmark)

    Gyimóthy, Szilvia; Munar, Ana María

    2013-01-01

    This paper advocates the need for a critical and cross-disciplinary research agenda on the field of digital technologies and tourism. The changing virtual landscape of tourism has received increased attention by tourism scholars. However, contemporary studies on information technologies (IT......) are approached mostly from a business administration perspective and informed by conceptual frameworks developed in management and marketing. IT studies in tourism are still at a stage similar to the first advocacy phase of tourism research in general (Jafari, 1990) and are seldom inspired by relevant...... to studying digital socio-technical systems and virtual mediation in tourism. Critical Digital Tourism Studies opens a new cross-disciplinary field where the sociality of virtual tourism interactions is examined (entailing the study of structures, social rules, ideologies, power relations, sustainability...

  1. International user studies

    DEFF Research Database (Denmark)

    Nielsen, Lene; Madsen, Sabine; Jensen, Iben

    In this report, we present the results of a research project about international user studies. The project has been carried out by researchers from the Center for Persona Research and –Application, The IT University in Copenhagen and the Department of Learning and Philosophy, Aalborg University...... in Sydhavnen, and it is funded by InfinIT. Based on a qualitative interview study with 15 user researchers from 11 different companies, we have investigated how companies collect and present data about users on international markets. Key findings are: Companies do not collect data about end users in all...... the countries/regions they operate in. Instead, they focus on a few strategic markets. International user studies tend to be large-scale studies that involve the effort of many both internal and external/local human resources. The studies typically cover 2-4 countries/regions and many end users in each country...

  2. Single Policy Study

    DEFF Research Database (Denmark)

    Kronsell, Annica; Manners, Ian James

    2015-01-01

    Single policy studies are the most common form of European Union (EU) research. Single policy studies are widely used to understand the role of the EU in a wide variety of sectors, together with their development over time, and often offer public policy prescriptions. This chapter discusses...... the relevance of single policy studies in EU research and give examples of how such research can be designed and carried out. The chapter reviews three examples of single policy studies using different methods based on EU environmental policy, the EU biofuels directive, and the EU Common Security and Defence...... Policy (CSDP). The examples are illustrative of how single policy studies can be designed to use different approaches in the analysis: multiple streams approach to policy-making; a comparative hypothesis testing; and feminist institutional theory....

  3. Recharge sources and hydro geochemical evaluations of Na2SO4 deposits in the Acıgöl Lake (Denizli, Turkey)

    Science.gov (United States)

    Kuşcu, Mustafa; Şener, Şehnaz; Tuncay, Ebru Başpınar

    2017-10-01

    Acıgöl Lake is the second largest alkaline lake in the world and is in a region that is one of the most important sodium sulphate production fields in Turkey. The present study focuses on determination of sources of the Na2SO4 deposits with main-trace element contents based on hydro-geochemical studies in the lake basin. The geological and hydrogeological properties of the study area were primarily determined. To identify the hydrogeochemical characteristics of spring/groundwater and lake water, chemical analyses results were evaluated with graphical plots such as Piper, Gibbs and Chadha diagrams and the conceptual hydrogeological model was prepared for the area. Mineral paragenesis of the lake sediments mainly consist of gypsum, aragonite, halite, calcite, dolomite, quartz, muscovite, smectite and illite besides tenardite, mirabilite and bloedite minerals. The dominant hydro geochemical facies are Na-SO4, Na-Cl, Ca-Mg-HCO3 and Ca-Mg-SO4 which are due to water-rock interaction. The mean Na, Ca, SO4, Cl and Mg concentrations in the spring waters are 221.27, 152.62, 374.81, 185.46 and 58.50 ppm respectively; whereas mean concentrations in the lake waters for Na, Ca, SO4, Cl and Mg ions are 22 507, 646, 16 186, 35 691 and 2399 ppm respectively. These major elements have very high concentrations in the lake waters due to the evaporation leading to enrichment. The main mechanism controlling water chemistry in the Acıgöl Lake basin is the process of water-rock interaction. The enrichment of these elements in the springs waters originate from lithological units such as sedimentary, ophiolitic and young magmatic rocks.

  4. Effective Physics Study Habits

    Science.gov (United States)

    Zettili, Nouredine

    2011-04-01

    We discuss the methods of efficient study habits and how they can be used by students to help them improve learning physics. In particular, we deal with ideas pertaining to the most effective techniques needed to help students improve their physics study skills. These ideas were developed as part of Project IMPACTSEED (IMproving Physics And Chemistry Teaching in SEcondary Education), an outreach grant funded by the Alabama Commission on Higher Education. This project is motivated by a major pressing local need: A large number of high school physics teachers teach out of field. In the presentation, focus on topics such as the skills of how to develop long term memory, how to improve concentration power, how to take class notes, how to prepare for and take exams, how to study scientific subjects such as physics. We argue that the student who conscientiously uses the methods of efficient study habits will be able to achieve higher results than the student who does not; moreover, a student equipped with the proper study skills will spend much less time to learn a subject than a student who has no good study habits. The underlying issue here is not the quantity of time allocated to the study efforts by the student, but the efficiency and quality of actions. This work is supported by the Alabama Commission on Higher Education as part of IMPACTSEED grant.

  5. The CIMESTRA study

    DEFF Research Database (Denmark)

    Hetland, Merete L; Hørslev-Petersen, Kim

    2013-01-01

    Treatment of early rheumatoid arthritis (RA) include aiming at disease control with early use of methotrexate (MTX) in monotherapy or in combination with glucocorticoids or other disease-modifying drugs (DMARDs). The CIMESTRA study applied an aggressive treatment with DMARD and intra-articular in......Treatment of early rheumatoid arthritis (RA) include aiming at disease control with early use of methotrexate (MTX) in monotherapy or in combination with glucocorticoids or other disease-modifying drugs (DMARDs). The CIMESTRA study applied an aggressive treatment with DMARD and intra......-articular injections of glucocorticoids (i.a. GC) to control disease activity. This paper reviews the results of the five years' study....

  6. Metabolomic Studies in Drosophila.

    Science.gov (United States)

    Cox, James E; Thummel, Carl S; Tennessen, Jason M

    2017-07-01

    Metabolomic analysis provides a powerful new tool for studies of Drosophila physiology. This approach allows investigators to detect thousands of chemical compounds in a single sample, representing the combined contributions of gene expression, enzyme activity, and environmental context. Metabolomics has been used for a wide range of studies in Drosophila, often providing new insights into gene function and metabolic state that could not be obtained using any other approach. In this review, we survey the uses of metabolomic analysis since its entry into the field. We also cover the major methods used for metabolomic studies in Drosophila and highlight new directions for future research. Copyright © 2017 by the Genetics Society of America.

  7. American Studies in Romania

    Directory of Open Access Journals (Sweden)

    Ioana Luca

    2006-01-01

    Full Text Available American Studies at the University of BucharestThe idea of teaching American Studies and founding a program in American Studies was first voiced in the long meetings of faculty and students held at the University of Bucharest soon after the collapse of the communist regime. The proposal was one of many that reflected the spirit of reform and hope for radical changes at the outset of Romania’s transition to democracy. The absence of institutional structures other than English departments and t...

  8. Border region studies

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Williams, Allan

    2016-01-01

    The contemporary conditions of academic capitalism exert pressures on researchers to avoid ‘peripheral’ journals and ‘unfashionable’ topics. Here an attempt is made to shed light onto the structure of one such ‘offbeat’ field, namely ‘border region studies’, by discussing its geographical...... distribution, key themes, significance and impact. The review suggests that border region studies can be considered a significant and important ‘branch’ of regional studies, which accounts for a small but increasing proportion of regional studies research particularly in Europe and North America. Four main...

  9. Building Transdisciplinary Environmental Studies

    DEFF Research Database (Denmark)

    Holm, Jesper

    We will in this paper approach the challenge of building integrated environmental studies by presenting a crude frame of analysis which take into account both the physical aspects and the social-discursive articulations of environmental problems. This framework partly mirrors the approach of our...... department (Dept. of Environment, Technology and Social Studies, Roskilde University), and has originally in another version been presented in the book “Miljøregulering - tværvidenskabelige studier (Environmental Regulation. Interdisciplinary Studies)” (Holm, Kjærgård & Pedersen eds. 1997, in Danish) written...

  10. Entrepreneurship and Process Studies

    DEFF Research Database (Denmark)

    Hjorth, Daniel; Holt, Robin; Steyaert, Chris

    2015-01-01

    and potential of processual approaches to studying, researching and practising entrepreneurship. The articles in the issue attest to an increasing sensitivity to processual thinking. We argue that appreciating entrepreneurial phenomena processually opens up the field to an understanding of entrepreneurship...... a variable as just that, a variable. The resonance with entrepreneurship studies is obvious. If any field is alive to, and fully resonant with, a processual understanding of, for example, the creation of firms, it is entrepreneurship studies. This special issue is an attempt to consider the promise...

  11. The CIMESTRA study

    DEFF Research Database (Denmark)

    Hetland, Merete L; Hørslev-Petersen, Kim

    2012-01-01

    Treatment of early rheumatoid arthritis (RA) include aiming at disease control with early use of methotrexate (MTX) in monotherapy or in combination with glucocorticoids or other disease-modifying drugs (DMARDs). The CIMESTRA study applied an aggressive treatment with DMARD and intra-articular in......Treatment of early rheumatoid arthritis (RA) include aiming at disease control with early use of methotrexate (MTX) in monotherapy or in combination with glucocorticoids or other disease-modifying drugs (DMARDs). The CIMESTRA study applied an aggressive treatment with DMARD and intra......-articular injections of glucocorticoids (i.a. GC) to control disease activity. This paper reviews the results of the five years' study....

  12. Willow ptarmigan study

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Willow ptarmigan (Lagopus lagopus; see Appendix I for scientific names of birds observed during this study) are a species of management interest because they are...

  13. Accelerator research studies

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under grant number DE-FG05-91ER40642, is currently in the first year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams, TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams; TASK C, Study of a Gyroklystron High-power Microwave Source for Linear Colliders. In this report we document the progress that has been made during the past year for each of the three tasks.

  14. a prospective study

    African Journals Online (AJOL)

    Akang . Departments of Medicine, Ogun State University Teaching Hospital, Sagama, “University College Hospital, Ibadan, and. Department of Pathology, University College Hospital, Ibadan, Nigeria. ABSTRACT. Background of the Study, Aims ...

  15. African Studies Monographs

    African Journals Online (AJOL)

    The African Studies Monographs is a serial that promotes research and scholarship on the African perspective worldwide. This includes matters of philosophy, history, literature, arts and culture, environment, gender, politics, administration crisis management, etc.

  16. Sport Foresight Study

    NARCIS (Netherlands)

    Marieke van Bakel; Ine Pulles; Annet Tiessen-Raaphorst; Frank den Hertog; Robert Vonk; Casper Schoemaker

    2017-01-01

    Original title: Sport Toekomstverkenning - een sportiever Nederland. In the Sport Foresight Study ‘Een sportiever Nederland’ (‘A more active Netherlands’), the Netherlands Institute for Social Research (SCP) and the Dutch National Institute for Public Health and the

  17. Six Heliport Case Studies

    National Research Council Canada - National Science Library

    Peisen, Deborah

    1997-01-01

    .... This report evaluates the dynamics of heliport development and operation in order to achieve greater success rate in the future through the case study investigation of six heliports that have both succeeded and failed...

  18. Comparative Packaging Study

    Science.gov (United States)

    Perchonok, Michele; Antonini, David

    2008-01-01

    This viewgraph presentation describes a comparative packaging study for use on long duration space missions. The topics include: 1) Purpose; 2) Deliverables; 3) Food Sample Selection; 4) Experimental Design Matrix; 5) Permeation Rate Comparison; and 6) Packaging Material Information.

  19. The street lifestyle study

    National Research Council Canada - National Science Library

    Weiler, Richard; Anderson, Jim; Caputo, Tullio

    1997-01-01

    The primary target population for this study was out-of-the-mainstream youth. Research sites were identified in Atlantic, Quebec, Ontario, Prairie and Pacific regions, and seventy-two young people were interviewed...

  20. Chamberino Floodplain Management Study

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The Dona Ana County Flood Commission requested the United States Department of Agriculture's Natural Resources Conservation Service to conduct a study of the...

  1. Pavement Subgrade Performance Study

    DEFF Research Database (Denmark)

    Zhang, Wei; Ullidtz, Per; Macdonald, Robin

    1998-01-01

    The report describes the second test in the Danish Road Testing Machine (RTM) under the International Pavement Subgrade Performance Study. Pavement response was measured in different layers, and compared to different theroretical values. Performance in terms of plastic strains, rutting...

  2. Cephradine antacids interaction studies

    National Research Council Canada - National Science Library

    Arayne, M Saeed; Sultana, Najma; Afzal, M

    2007-01-01

    .... The behavior of cephradine in presence of seven antacids i.e., simethicone, magaldrate, magnesium carbonate, magnesium hydroxide, magnesium trisilicate, sodium bicarbonate and aluminium hydroxide was studied by using standard dissolution apparatus...

  3. 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...

  4. The PRIMARA study

    DEFF Research Database (Denmark)

    Schwarz, P; Body, J J; Cáp, J

    2014-01-01

    OBJECTIVE: Medical management of primary hyperparathyroidism (PHPT) is important in patients for whom surgery is inappropriate. We aimed to describe clinical profiles of adults with PHPT receiving cinacalcet. DESIGN: A descriptive, prospective, observational study in hospital and specialist care ...

  5. Digital signature feasibility study

    Science.gov (United States)

    2008-06-01

    The purpose of this study was to assess the advantages and disadvantages of using digital signatures to assist the Arizona Department of Transportation in conducting business. The Department is evaluating the potential of performing more electronic t...

  6. Sport Forward Study

    NARCIS (Netherlands)

    Marieke van Bakel; Ine Pulles; Annet Tiessen-Raaphorst; Frank den Hertog; Robert Vonk; Casper Schoemaker

    2017-01-01

    Original title: Sport Toekomstverkenning - een sportiever Nederland. In the Sport Forward Study ‘Een sportiever Nederland’ (‘A more active Netherlands’), the Netherlands Institute for Social Research (SCP) and the Dutch National Institute for Public Health and the

  7. Applied Research Study

    Science.gov (United States)

    Leach, Ronald J.

    1997-01-01

    The purpose of this project was to study the feasibility of reusing major components of a software system that had been used to control the operations of a spacecraft launched in the 1980s. The study was done in the context of a ground data processing system that was to be rehosted from a large mainframe to an inexpensive workstation. The study concluded that a systematic approach using inexpensive tools could aid in the reengineering process by identifying a set of certified reusable components. The study also developed procedures for determining duplicate versions of software, which were created because of inadequate naming conventions. Such procedures reduced reengineering costs by approximately 19.4 percent.

  8. Event studies in Turkey

    National Research Council Canada - National Science Library

    Basdas, Ulkem; Oran, Adil

    2014-01-01

    ...) market index and market adjusted returns with the parametric tests. In general, the studies prefer to rely on one type of model to calculate abnormal returns without discussing the selection of the underlying model...

  9. Techno-economic Study

    DEFF Research Database (Denmark)

    Sigurdsson, Halldór Matthias; Point, J.C.; Million, P.

    A techno-economic model for analysing and comparing broadband deployment strategies has been established. The resulting simulation model can compare Capital Expenditure (CAPEX) of dominating broadband technologies in different types of demographic areas. The study reveals the competitiveness...

  10. Studying bacterial multispecies biofilms

    DEFF Research Database (Denmark)

    Røder, Henriette Lyng; Sørensen, Søren Johannes; Burmølle, Mette

    2016-01-01

    the approaches used to study these complex communities. This review focuses on the establishment of multispecies biofilms in vitro, interspecies interactions in microhabitats, and how to select communities for evaluation. Studies have used different experimental approaches; here we evaluate the benefits......, but the identity and significance of interspecies bacterial interactions is neglected in these analyses. There is therefore an urgent need for bridging the gap between metagenomic analysis and in vitro models suitable for studies of bacterial interactions.Bacterial interactions and coadaptation are important...... at the microscale of complex communities, including biofilms.Studies of multispecies biofilms and the interactions shaping these are conducted in traditional approaches used for single-species biofilms with some adjustments; but a crucial point for consideration is which strains to combine and where these should...

  11. Venus Aerial Platform Study

    Science.gov (United States)

    Cutts, J. A.

    2017-11-01

    A Venus Aerial Platform Study, which was underway in early 2017, is assessing the science and technologies for exploring Venus with aerial vehicles in order to develop a Venus Aerial Platform Roadmap for the future exploration of the planet.

  12. Esophagram (Barium Swallow Study)

    Science.gov (United States)

    ... Impulse Oscillimetry (IOS) Hypoxic and Hypercapnic Drive Response Lung Diffusion Capacity Testing (DLCO) Maximum Inspiratory/Expiratory Pressures Nitrogen Washout Performing Pressure Volume Study Performing Routine Pulmonary Test Performing Spirometry Test ...

  13. Tailored Barium Swallow Study

    Science.gov (United States)

    ... Impulse Oscillimetry (IOS) Hypoxic and Hypercapnic Drive Response Lung Diffusion Capacity Testing (DLCO) Maximum Inspiratory/Expiratory Pressures Nitrogen Washout Performing Pressure Volume Study Performing Routine Pulmonary Test Performing Spirometry Test ...

  14. Upper Kenai Corridor Study

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Upper Kenai Corridor study describes and evaluates the Upper Kenai River and the land which embraces it. It also places the river corridor in its regional...

  15. Groundwater salinization processes and reversibility of seawater intrusion in coastal carbonate aquifers

    Science.gov (United States)

    Han, Dongmei; Post, Vincent E. A.; Song, Xianfang

    2015-12-01

    Seawater intrusion (SWI) has led to salinization of fresh groundwater reserves in coastal areas worldwide and has forced the closure of water supply wells. There is a paucity of well-documented studies that report on the reversal of SWI after the closure of a well field. This study presents data from the coastal carbonate aquifer in northeast China, where large-scale extraction has ceased since 2001 after salinization of the main well field. The physical flow and concomitant hydrogeochemical processes were investigated by analyzing water level and geochemical data, including major ion chemistry and stable water isotope data. Seasonal water table and salinity fluctuations, as well as changes of δ2H-δ18O values of groundwater between the wet and dry season, suggest local meteoric recharge with a pronounced seasonal regime. Historical monitoring testifies of the reversibility of SWI in the carbonate aquifer, as evidenced by a decrease of the Cl- concentrations in groundwater following restrictions on groundwater abstraction. This is attributed to the rapid flushing in this system where flow occurs preferentially along karst conduits, fractures and fault zones. The partially positive correlation between δ18O values and TDS concentrations of groundwater, as well as high NO3- concentrations (>39 mg/L), suggest that irrigation return flow is a significant recharge component. Therefore, the present-day elevated salinities are more likely due to agricultural activities rather than SWI. Nevertheless, seawater mixing with fresh groundwater cannot be ruled out in particular where formerly intruded seawater may still reside in immobile zones of the carbonate aquifer. The massive expansion of fish farming in seawater ponds in the coastal zone poses a new risk of salinization. Cation exchange, carbonate dissolution, and fertilizer application are the dominant processes further modifying the groundwater composition, which is investigated quantitatively using hydrogeochemical

  16. Hydrogeochemistry and water quality of the Kordkandi-Duzduzan plain, NW Iran: application of multivariate statistical analysis and PoS index.

    Science.gov (United States)

    Soltani, Shahla; Asghari Moghaddam, Asghar; Barzegar, Rahim; Kazemian, Naeimeh; Tziritis, Evangelos

    2017-08-18

    Kordkandi-Duzduzan plain is one of the fertile plains of East Azarbaijan Province, NW of Iran. Groundwater is an important resource for drinking and agricultural purposes due to the lack of surface water resources in the region. The main objectives of the present study are to identify the hydrogeochemical processes and the potential sources of major, minor, and trace metals and metalloids such as Cr, Mn, Cd, Fe, Al, and As by using joint hydrogeochemical techniques and multivariate statistical analysis and to evaluate groundwater quality deterioration with the use of PoS environmental index. To achieve these objectives, 23 groundwater samples were collected in September 2015. Piper diagram shows that the mixed Ca-Mg-Cl is the dominant groundwater type, and some of the samples have Ca-HCO3, Ca-Cl, and Na-Cl types. Multivariate statistical analyses indicate that weathering and dissolution of different rocks and minerals, e.g., silicates, gypsum, and halite, ion exchange, and agricultural activities influence the hydrogeochemistry of the study area. The cluster analysis divides the samples into two distinct clusters which are completely different in EC (and its dependent variables such as Na+, K+, Ca2+, Mg2+, SO42-, and Cl-), Cd, and Cr variables according to the ANOVA statistical test. Based on the median values, the concentrations of pH, NO3-, SiO2, and As in cluster 1 are elevated compared with those of cluster 2, while their maximum values occur in cluster 2. According to the PoS index, the dominant parameter that controls quality deterioration is As, with 60% of contribution. Samples of lowest PoS values are located in the southern and northern parts (recharge area) while samples of the highest values are located in the discharge area and the eastern part.

  17. Tanzania country study

    Energy Technology Data Exchange (ETDEWEB)

    Meena, H.E. [Centre for Energy, Environment, Science and Technology, Dar es Salaam (Tanzania, United Republic of)

    1998-10-01

    An objective of this study is to analyse the role of the land use sectors of Tanzania (especially forestry) on mitigation of greenhouse gases. Specific emphasis is placed on the relationship between forestry and energy supply from biomass. This is a follow up study on an earlier effort which worked on mitigation options in the country without an in-depth analysis of the forestry and land use sectors. (au)

  18. Future ATLAS Higgs Studies

    CERN Document Server

    Smart, Ben; The ATLAS collaboration

    2017-01-01

    The High-Luminosity LHC will prove a challenging environment to work in, with for example $=200$ expected. It will however also provide great opportunities for advancing studies of the Higgs boson. The ATLAS detector will be upgraded, and Higgs prospects analyses have been performed to assess the reach of ATLAS Higgs studies in the HL-LHC era. These analyses are presented, as are Run-2 ATLAS di-Higgs analyses for comparison.

  19. Artificial Intelligence Study (AIS).

    Science.gov (United States)

    1987-02-01

    ARTIFICIAL INTELLIGNECE HARDWARE ....... 2-50 AI Architecture ................................... 2-49 AI Hardware ....................................... 2...ftf1 829 ARTIFICIAL INTELLIGENCE STUDY (RIS)(U) MAY CONCEPTS 1/3 A~NLYSIS AGENCY BETHESA RD R B NOJESKI FED 6? CM-RP-97-1 NCASIFIED /01/6 M |K 1.0...p/ - - ., e -- CAA- RP- 87-1 SAOFŔ)11 I ARTIFICIAL INTELLIGENCE STUDY (AIS) tNo DTICFEBRUARY 1987 LECT 00 I PREPARED BY RESEARCH AND ANALYSIS

  20. Concrete containment aging study

    Energy Technology Data Exchange (ETDEWEB)

    Pachner, J. [International Atomic Energy Agency, Vienna (Austria); Tai, T.M. [Bechtel National, Inc., Oak Ridge, TN (United States); Naus, D. [Oak Ridge National Lab., TN (United States)

    1994-04-01

    In 1989, IAEA initiated a pilot study on the management of aging of nuclear power plant components. The Phase I and II studies of concrete containment are discussed. With the data base, plant owners will be able to review and enhance their existing programs. IAEA will analyze data provided by participating plants and the report is scheduled to be released by late 1994 (final report release mid-1995).

  1. Zambia country study

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    The Zambia Country Study, which was part of the Danida-funded project Climate Change Mitigation in Southern Africa: Phase 2, aimed at methodological development, national mitigation analysis and institutional capacity building in Zambia. The study comprised the following five elements: Comprehensive evaluation of national social and economic development framework for climate change; Baseline scenario(s) projection(s); Mitigation scenario(s) projection(s); Macro-economic assessment; Implementation Issues. (au) 17 refs.

  2. a field study

    OpenAIRE

    Köster, Gudrun

    2010-01-01

    Factors influencing udder health and prevalence of mastitis pathogens and their resistance to antimicrobials in large dairy herds in Brandenburg, Germany- a field study The objective of the field study was to 1) investigate factors influencing udder health in dairy herds in Brandenburg, Germany and 2) to describe prevalence and spreading of mastitis pathogens and their resistance patterns to antimicrobials. Eighty dairy farms were visited between July 2001 and October 2002. Data were evalu...

  3. Background Studies for EXIST

    Science.gov (United States)

    Wilson, Colleen A.; Pendleton, G. N.; Fishman, G. J.

    2004-01-01

    We present results from a study of the trapped proton and electron background for several orbital inclinations and altitudes. This study includes time dependent effects. In addition we describe a 3 component cosmic background model developed at the University of Southampton, UK. The three components are cosmic diffuse gamma rays, atmospheric albedo gamma rays, and cosmic ray protons. We present examples of how this model was applied to BATSE and discuss its application to EXIST.

  4. Networked Microgrids Scoping Study

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dobriansky, Larisa [General MicroGrids, San Diego, CA (United States); Glover, Steve [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Liu, Chen-Ching [Washington State Univ., Pullman, WA (United States); Looney, Patrick [Brookhaven National Lab. (BNL), Upton, NY (United States); Mashayekh, Salman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Pratt, Annabelle [National Renewable Energy Lab. (NREL), Golden, CO (United States); Schneider, Kevin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stadler, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Starke, Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States); Yue, Meng [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-12-05

    Much like individual microgrids, the range of opportunities and potential architectures of networked microgrids is very diverse. The goals of this scoping study are to provide an early assessment of research and development needs by examining the benefits of, risks created by, and risks to networked microgrids. At this time there are very few, if any, examples of deployed microgrid networks. In addition, there are very few tools to simulate or otherwise analyze the behavior of networked microgrids. In this setting, it is very difficult to evaluate networked microgrids systematically or quantitatively. At this early stage, this study is relying on inputs, estimations, and literature reviews by subject matter experts who are engaged in individual microgrid research and development projects, i.e., the authors of this study The initial step of the study gathered input about the potential opportunities provided by networked microgrids from these subject matter experts. These opportunities were divided between the subject matter experts for further review. Part 2 of this study is comprised of these reviews. Part 1 of this study is a summary of the benefits and risks identified in the reviews in Part 2 and synthesis of the research needs required to enable networked microgrids.

  5. Partial gravity habitat study

    Science.gov (United States)

    Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kiosuke

    1989-01-01

    The purpose of this study is to investigate comprehensive design requirements associated with designing habitats for humans in a partial gravity environment, then to apply them to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable-gravity research facilities, and a rotating spacecraft. Design requirements for partial gravity environments include locomotion changes in less than normal earth gravity; facility design issues, such as interior configuration, module diameter, and geometry; and volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a lunar base, it is necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress; radiation protection issues are addressed to provide a safe and healthy environment for the crew; and finally, the overall site is studied to locate all associated facilities in context with the habitat. Mission planning is not the purpose of this study; therefore, a Lockheed scenario is used as an outline for the lunar base application, which is then modified to meet the project needs. The goal of this report is to formulate facts on human reactions to partial gravity environments, derive design requirements based on these facts, and apply the requirements to a partial gravity situation which, for this study, was a lunar base.

  6. Studying Organizations on Instagram

    Directory of Open Access Journals (Sweden)

    Uta Russmann

    2016-10-01

    Full Text Available With the rise of social media platforms based on the sharing of pictures and videos, the question of how such platforms should be studied arises. Previous research on social media (content has mainly focused on text (written words and the rather text-based social media platforms Twitter and Facebook. Drawing on research in the fields of visual, political, and business communication, we introduce a methodological framework to study the fast-growing image-sharing service Instagram. This methodological framework was developed to study political parties’ Instagram accounts and tested by means of a study of Swedish political parties during the 2014 election campaign. In this article, we adapt the framework to also study other types of organizations active on Instagram by focusing on the following main questions: Do organizations only use Instagram to share one-way information, focusing on disseminating information and self-presentation? Or is Instagram used for two-way communication to establish and cultivate organization-public relationships? We introduce and discuss the coding of variables with respect to four clusters: the perception of the posting, image management, integration, and interactivity.

  7. Photovoltaics information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marie, T.L.; Reinhardt, C.L.

    1980-10-01

    The results of a series of telephone interviews with groups of users of information on photovoltaics (PV) are described. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The report is 1 of 10 discussing study results. The overall study provides baseline data about information needs in the solar community. It covers these technological areas: photovoltaics, passive solar heating and cooling, active solar heating and cooling, biomass energy, solar thermal electric power, solar industrial and agricultural process heat, wind energy, ocean energy, and advanced energy storage. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from seven PV groups respondents are analyzed in this report: DOE-Funded Researchers, Non-DOE-Funded Researchers, Researchers Working for Manufacturers, Representatives of Other Manufacturers, Representatives of Utilities, Electric Power Engineers, and Educators.

  8. The Rhume springs revisited: A multi-tracer approach to one of the largest European carbonate-gypsum karst systems

    Science.gov (United States)

    Böttcher, Michael E.; Schmiedinger, Iris; Dellwig, Olaf; Escher, Peter; Weise, Stephan M.

    2014-05-01

    Modern karst ground water systems are at the cutting edge between atmosphere, hydrosphere, and geosphere and are impacted by the biosphere and anthroposphere. The hydrogeochemical processes in karst terrains are sensitive to both climate change and anthropogenic activity, thereby affecting the quality of these ground waters. Therefore, understanding the transport processes and hydrogeochemical interactions between surface and ground waters is of fundamental importance for the prediction of future quality developments of large drinking water resources. The system of the Rhume spring, at the SW border of the Harz Mountains (Germany), one of the largest the largest European karst springs, has been investigated for hydrogeochemical and isotope variations to study the impact of river waters on the Rhume spring system. Rivers from the Harz Mountains are infiltrating Quaternary strata and emerging, after a passage through Permian (Zechstein) carbonate and sulfate rocks at the Rhume springs. By using a hydrogeochemical tracer approach it was found earlier, that an old mineralized ground water that had been modified by subterrestrial water-rock interactions is mixed with less mineralized younger karst waters before emerging in the different Rhume spring pits [1-4]. In the present communication, we present new results from a revisit of the Rhume springs and the rivers and streams in the direct and tributary recharge areas focussing on trace metal concentrations and multi-stable isotope signatures under different hydrological conditions. It was the aim of the investigation to re-analyze the proposed mixing model and provide additional evidence for a relative age estimate (H-3 dating) of the different waters emerging in the Rhume spring area. One focus was set on a high water-impact period. By the application of a multi-tracer approach (e.g., Sr, Ba, Fe, Mn, Mo, PO4, Si), and different isotope systems (S-32/S-34 in sulfate; O-16, O-17, O-18, H-1, H-2, and H-3 in water, C-12/C

  9. Explorative analysis of microbes, colloids and gases

    Energy Technology Data Exchange (ETDEWEB)

    Hallbeck, Lotta; Pedersen, Karsten (Microbial Analytics Sweden AB, Goeteborg (Sweden))

    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. In this report, part of 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 Univ. researchers with expertise in geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on 2.2 data and complementary 2.3 data, was carried out during September 2006 to December 2007. This report focuses on microbiology, colloids and gases: - Microbes (Chapter 1): Several methods must be used to characterize active microbial communities in groundwater. Microbial parameters of interest are the total number of cells (TNC) and the presence of various metabolic groups of microorganisms. Different microbial groups influence the environment in different ways, depending on what metabolic group is dominant. Typically, the following redox couples are utilized by bacteria in granitic groundwater: H{sub 2}O/O{sub 2}, NO{sub 3}-/N{sub 2}, Mn2+/Mn(IV), Fe2+/Fe(III), S2-/SO{sub 4}2-, CH{sub 4}/CO{sub 2}, CH{sub 3}COOH/CO{sub 2}, and H{sub 2}/H+. The data will indicate the activity of specific microbial populations at particular sites and how they may affect the geochemistry. - Colloids (Chapter 2): Particles in the size range from 1 to 1x10-3 mum are regarded as colloids. Their small size prohibits them from settling, which gives them the

  10. Oxidizer Scoping Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chancellor, Christopher John [Los Alamos National Laboratory

    2016-11-07

    The purpose of this report is to present the results of the acceptable knowledge (AK) review of oxidizers present in active waste streams, provide a technical analysis of the oxidizers, and report the results of the scoping study testing. This report will determine the fastest burning oxidizer to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-002, Sorbent Scoping Studies, contains similar information for sorbents identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  11. Esperance pica study.

    Science.gov (United States)

    Ardeshirian, Kuroush A; Howarth, Donald A

    2017-01-01

    Pica, the eating of non-foods, occurs particularly in children and pregnant women. It has been observed in communities all over the world. Pica is associated with iron deficiency and, in some environments, lead poisoning. This is the first time a study has assessed the prevalence of pica in Australia. The study assessed the prevalence of pica in an Australian rural community, using a questionnaire given to parents of 223 children aged 2-10 years attending the five general practice surgeries in the shire. The prevalence of non-ice pica in the study group was 9.4%, and 3.6% of this group ate soil. The presence of pica should alert the treating clinician to consider iron deficiency and, in the case of polluted environments, lead exposure.

  12. Parylene C Aging Studies.

    Energy Technology Data Exchange (ETDEWEB)

    Achyuthan, Komandoor; Sawyer, Patricia Sue.; Mata, Guillermo Adrian; White II, Gregory Von; Bernstein, Robert

    2014-09-01

    Parylene C is used in a device because of its conformable deposition and other advantages. Techniques to study Parylene C aging were developed, and "lessons learned" that could be utilized for future studies are the result of this initial study. Differential Scanning Calorimetry yielded temperature ranges for Parylene C aging as well as post-deposition treatment. Post-deposition techniques are suggested to improve Parylene C performance. Sample preparation was critical to aging regimen. Short-term (%7E40 days) aging experiments with free standing and ceramic-supported Parylene C films highlighted "lessons learned" which stressed further investigations in order to refine sample preparation (film thickness, single sided uniform coating, machine versus laser cutting, annealing time, temperature) and testing issues ("necking") for robust accelerated aging of Parylene C.

  13. Studie-Units

    DEFF Research Database (Denmark)

    Koustrup, Pia

    2004-01-01

    Denne artikel sætter fokus på tilrettelæggelse af klinisk undervisning og læring, hvor et nyere begreb - studie-units er opstået inden for de sidste par år. Studie-unit er en organisationsform, som sygeplejen helt sikkert vil se en del mere til de næste par år frem i tiden. Artiklen inddrager den...... tyske didaktiker og filosof Wolfgang Klafki i diskussionen om indføring af studie-units. Klafki er valgt, fordi han indgående forholder sig til social læring, og finder læring i fællesskab med ligestillede nødvendigt for at dannelsen i et fag skal kunne lykkes...

  14. Gold induced apoptsis study

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    2008-01-01

    Introduction   Cancer cells are highly thermo sensitive. On the basis of an article in Nature the idea arose, for a new non-invasive thermotherapy technique, based on radio frequency inductive heating of nano gold particles in an MR-scanner. Thermotherapy is getting considerably attention...... at the moment, especially in the fields of lasers, they though have some problems concerning the placement of the tumor in the human body. Local heating by MR has tremendous advance in comparison too lasers. The first step is to validate the hypothesis of the inductive heating of the gold nano particles trough...... in silico methods are here proposed for apoptosis studies and for AMG studies.   Methods   MR - heating of high concentration micrometer gold and low concentration nano gold.   CSLM of ethidum bromide stained cell lines, with and witout gold and automated image processing.   AMG gold uptake study...

  15. The Hi Five study

    DEFF Research Database (Denmark)

    Johansen, Anette; Denbæk, Anne Maj; Bonnesen, Camilla Thørring

    2015-01-01

    BACKGROUND: Infectious illnesses such as influenza and diarrhea are leading causes of absenteeism among Danish school children. Interventions in school settings addressing hand hygiene have shown to reduce the number of infectious illnesses. However, most of these studies include small populations...... and almost none of them are conducted as randomized controlled trials. The overall aim of the Hi Five study was to develop, implement and evaluate a multi-component school-based intervention to improve hand hygiene and well-being and to reduce the prevalence of infections among school children...... in intervention schools by 20% compared to control schools. This paper describes the development and the evaluation design of Hi Five. METHODS/DESIGN: The Hi Five study was designed as a tree-armed cluster-randomized controlled trial. A national random sample of schools (n = 44) was randomized to one of two...

  16. Pirating European Studies

    Directory of Open Access Journals (Sweden)

    Natalia Timus

    2016-08-01

    Full Text Available Open Science has gained a lot of attention not only within the academic community but also among policy-makers. Some international publishers have been active in moving towards open access publications and research data, but, overall, modest results have been achieved so far. In this context, the digital piracy engines emerge as vital actors in disseminating and determining the impact of research. This study examines the Sci-Hub downloads data in order to uncover patterns of piracy in European Studies research. We identify journals and the subjects of articles that have been pirated the most. We also study the geographical distribution of download requests. The analysis reveals that the readers are mostly interested in subjects reflecting the current major European challenges, specifically populism and the economic crisis. Both developing countries as well as the ‘old’ EU members are active in illegal downloads.

  17. Wright Field turboprop study

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzetti, R.C.; Dull, P.P.

    1981-01-01

    The considered investigation was conducted as part of an effort to reduce aircraft fuel costs. Turboprops are very fuel efficient at speeds below Mach 0.6. One of the most promising approaches to reduce fuel consumption in the speed range from Mach 0.6 to 0.8 is related to an employment of the swept eight to ten blade propeller (propfan) being developed by NASA. All studies to date indicate that turboshaft engines with propfans might save 15% or more of the fuel used by a turbofan engine of comparable technology. Attention is given to a turboprop status review, contractor studies, the NASA propfan program, an in-house performance study, specific problems which have to be solved to make a twin-turboprop, 100-150 passenger transport a viable possibility for the early 1990s, and turboprop dilemmas.

  18. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... Studies Learn more about Children and Clinical Studies Importance of Children in Clinical Studies Children have often ... participants. Children and Clinical Studies Learn about the importance of children in clinical studies and get answers ...

  19. Chemical modeling of groundwater in the Banat Plain, southwestern Romania, with elevated As content and co-occurring species by combining diagrams and unsupervised multivariate statistical approaches.

    Science.gov (United States)

    Butaciu, Sinziana; Senila, Marin; Sarbu, Costel; Ponta, Michaela; Tanaselia, Claudiu; Cadar, Oana; Roman, Marius; Radu, Emil; Sima, Mihaela; Frentiu, Tiberiu

    2017-04-01

    The study proposes a combined model based on diagrams (Gibbs, Piper, Stuyfzand Hydrogeochemical Classification System) and unsupervised statistical approaches (Cluster Analysis, Principal Component Analysis, Fuzzy Principal Component Analysis, Fuzzy Hierarchical Cross-Clustering) to describe natural enrichment of inorganic arsenic and co-occurring species in groundwater in the Banat Plain, southwestern Romania. Speciation of inorganic As (arsenite, arsenate), ion concentrations (Na+, K+, Ca2+, Mg2+, HCO3-, Cl-, F-, SO42-, PO43-, NO3-), pH, redox potential, conductivity and total dissolved substances were performed. Classical diagrams provided the hydrochemical characterization, while statistical approaches were helpful to establish (i) the mechanism of naturally occurring of As and F- species and the anthropogenic one for NO3-, SO42-, PO43- and K+ and (ii) classification of groundwater based on content of arsenic species. The HCO3- type of local groundwater and alkaline pH (8.31-8.49) were found to be responsible for the enrichment of arsenic species and occurrence of F- but by different paths. The PO43--AsO43- ion exchange, water-rock interaction (silicates hydrolysis and desorption from clay) were associated to arsenate enrichment in the oxidizing aquifer. Fuzzy Hierarchical Cross-Clustering was the strongest tool for the rapid simultaneous classification of groundwaters as a function of arsenic content and hydrogeochemical characteristics. The approach indicated the Na+-F--pH cluster as marker for groundwater with naturally elevated As and highlighted which parameters need to be monitored. A chemical conceptual model illustrating the natural and anthropogenic paths and enrichment of As and co-occurring species in the local groundwater supported by mineralogical analysis of rocks was established. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Size- and concentration-dependent deposition of fluorescent silica colloids in saturated sand columns: transport experiments and modeling.

    Science.gov (United States)

    Vitorge, Elsa; Szenknect, Stéphanie; Martins, Jean M F; Gaudet, Jean-Paul

    2013-08-01

    This study investigates the size and concentration effects on the transport of silica colloids in columns of sandy aquifer material. Colloid transport experiments were performed with specifically developed fluorescent labeled silica colloids in columns of a repacked natural porous medium under hydro-geochemical conditions representative of sandy aquifers. Breakthrough curves and vertical deposition profiles of colloids were measured for various colloid concentrations and sizes. The results showed that for a given colloid concentration injected, deposition increased when increasing the size of the colloids. For a given colloid size, retention was also shown to be highly concentration-dependent with a non-monotonous pattern presenting low and high concentration specificities. Deposition increases when increasing both size and injected concentration, until a threshold concentration is reached, above which retention decreases, thus increasing colloid mobility. Results observed above the threshold concentration agree with a classical blocking mechanism typical of a high concentration regime. Results observed at lower colloid concentrations were not modeled with a classical blocking model and a depth- and time-dependent model with a second order kinetic law was necessary to correctly fit the experimental data in the entire range of colloid concentrations with a single set of parameters for each colloidal size. The colloid deposition mechanisms occuring at low concentrations were investigated through a pore structure analysis carried out with Mercury Intrusion Porosimetry and image analysis. The determined pore size distribution permitted estimation of the maximal retention capacity of the natural sand as well as some low flow zones. Altogether, these results stress the key role of the pore space geometry of the sand in controlling silica colloids deposition under hydro-geochemical conditions typical of sandy aquifers. Our results also showed originally that colloid

  1. Assessing seawater intrusion in an arid coastal aquifer under high anthropogenic influence using major constituents, Sr and B isotopes in groundwater.

    Science.gov (United States)

    Mahlknecht, J; Merchán, D; Rosner, M; Meixner, A; Ledesma-Ruiz, R

    2017-06-01

    The La Paz aquifer system (Baja California Sur, Mexico) is under severe anthropogenic pressure because of high groundwater abstraction for urban supply (city of La Paz, around 222,000 inhabitants) and irrigated agriculture (1900ha). In consequence, seawater has infiltrated the aquifer, forcing the abandonment of wells with increased salinity. The objective of this study was to assess seawater intrusion, understand the hydrogeochemical processes involved and estimate the contribution of seawater in the wells tested. The aquifer comprises mainly the alluvial filling and marine sediments of a tectonic graben oriented north-south, in contact with the Gulf of California. Groundwater samples were collected in 47 locations and analyzed for major constituents. A subset of 23 samples was analyzed for strontium and boron concentrations and isotopic signatures ((87)Sr/(86)Sr and δ(11)B). Results were interpreted using standard hydrochemical plots along with ad hoc plots including isotopic data. Seawater intrusion was confirmed by several hydrogeochemical indicators, such as the high salinity in areas of intense pumping or the Na(+)-Ca(2+) exchange occurring in sediments that were previously in chemical equilibrium with fresh water. However, seawater contribution was not sufficient to explain the observed concentrations and isotopic signatures of Sr and B. According to the isotopic data, desorption processes triggered by a modification in chemical equilibrium and an increase in ionic strength by seawater intrusion significantly increased Sr and probably B concentrations in groundwater. From a calculation of seawater contribution to the wells, it was estimated that one-third of the sampled abstraction wells were significantly affected by seawater intrusion, reaching concentrations that would limit their use for human supply or even irrigated agriculture. In addition, significant agricultural pollution (nitrates) was detected. Planned management of the aquifer and corrective

  2. Observations and Prediction of Recovered Quality of Desalinated Seawater in the Strategic ASR Project in Liwa, Abu Dhabi

    Directory of Open Access Journals (Sweden)

    Pieter J. Stuyfzand

    2017-03-01

    Full Text Available To be able to overcome water shortages, Abu Dhabi Emirate started an Aquifer Storage and Recovery (ASR project with desalinated seawater (DSW as source water near Liwa. It is the largest DSW-ASR project in the world (stored volume ~10 Mm3/year, and should recover potable water for direct use. DSW is infiltrated into a desert dune sand aquifer using “sand-covered gravel-bed” recharge basins. In this study, we evaluate the hydrogeological and hydrogeochemical stratification of the (suboxic target aquifer, and water quality changes of DSW during trial infiltration runs. We predict water quality changes of DSW after 824 d of infiltration, during 90 d of intensive recovery (67% recovered without storage (scenario A, as well as after 10 years of storage (scenario B, with significant bubble drift. Monitoring of preceding trials revealed a lack of redox reactions; little carbonate dissolution and Ca/Na exchange; much SiO2 dissolution; a strong mobilization of natural AsO43−, B, Ba, F, CrO42−, Mo, Sr and V from the (suboxic aquifer; and immobilization of PO4, Al, Cu, Fe and Ni from DSW. The Easy-Leacher model was applied in forward and reverse mode including lateral bubble drift, to predict water quality of the recovered water. We show that hydrogeochemical modeling of a complex ASR-system can be relatively easy and straightforward, if aquifer reactivity is low and redox reactions can be ignored. The pilot observations and modeling results demonstrate that in scenario A recovered water quality still complies with Abu Dhabi’s drinking water standards (even up to 85% recovery. For scenario B, however, the recovery efficiency declines to 60% after which various drinking water standards are exceeded, especially the one for chromium.

  3. Critical cyberculture studies

    CERN Document Server

    Silver, David; Jones, Steve

    2006-01-01

    Starting in the early 1990s, journalists and scholars began responding to and trying to take account of new technologies and their impact on our lives. By the end of the decade, the full-fledged study of cyberculture had arrived. Today, there exists a large body of critical work on the subject, with cutting-edge studies probing beyond the mere existence of virtual communities and online identities to examine the social, cultural, and economic relationships that take place online. Taking stock of the exciting work that is being done and positing what cyberculture's future might look like, Criti

  4. Fireset materials aging study

    Energy Technology Data Exchange (ETDEWEB)

    Smith, H.M.; Arnold, C.; Bailey, M.E.

    1982-07-01

    A thermally-accelerated aging study of 10 selected organic materials used in a fireset has been conducted. The study included both quantitative and qualitative gas analyses as well as the measurement of physical properties before and after accelerated aging. The test plan involved single material aging, as well as pairs and larger groups to look for synergistic interactions. The material types tested were epoxies, polyurethanes, polysulfides, silicones, phenolics, polyolefins, and diallyl phthalates. Only two of the materials tested showed evidence of degradation as a result of aging.

  5. A longitudinal study

    OpenAIRE

    Kristen, Astrid

    2010-01-01

    Does playing violent video games increase aggressive behavior over time or is it aggressive children who increasingly seek out (and play) these violent video games? To study such long-term effects a longitudinal design is necessary. Within a field study in a large German city (Kinder, Computer, Hobby, Lernen – KUHL, Freie Universtität Berlin) about 115 elementary school boys attending in the beginning (t1) classrooms of the third and fourth grade and twelve months later (t2) classrooms of the...

  6. CCNA Wireless Study Guide

    CERN Document Server

    Lammle, Todd

    2010-01-01

    A complete guide to the CCNA Wireless exam by leading networking authority Todd Lammle. The CCNA Wireless certification is the most respected entry-level certification in this rapidly growing field. Todd Lammle is the undisputed authority on networking, and this book focuses exclusively on the skills covered in this Cisco certification exam. The CCNA Wireless Study Guide joins the popular Sybex study guide family and helps network administrators advance their careers with a highly desirable certification.: The CCNA Wireless certification is the most respected entry-level wireless certification

  7. Morphing Terminology Study

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Stuart J.; Brockman, Fred J.; Hart, Michelle L.; Engel, David W.; Valentine, Nancy B.; Calapristi, Augustin J.

    2010-06-28

    This study investigates methods of automatically identifying and characterizing significant transitions in term usage over time. Within scientific literature, the occurrence of terms reflects the use of technologies and techniques as well as the study of specific species and materials. Transitions in terminology usage may be a result of vocabulary standardization or specialization in which terms are replaced with their shorter form. They may also be a result of new applications, combinations, alternatives, or interests that result in the appearance of new or existing terminology in unexpected contexts.

  8. Radionuclide studies in impotence

    Energy Technology Data Exchange (ETDEWEB)

    Hilson, A.J.; Lewis, C.A. (St. Peter' s Hospitals, London (England))

    1991-04-01

    Impotence may be of physiological origin with causes including vascular or neurological pathology. Alternatively, it may be of psychogenic origin. Clinicians can distinguish between psychological and organic impotence by observing nocturnal penile tumescence. Non-radionuclide investigations for organic impotence include penile plethysmography or pulse Doppler analysis for arterial supply, cavernosometry for venous drainage, and biothesiometry or evoked potentials for neurological pathology. Radionuclide studies are primarily based on the use of technetium 99m-pertechnetate, 99mTc-red blood cells, or xenon 133 to study the blood flow, with or without pharmacological intervention, commonly papaverine. 26 references.

  9. Study of genital lesions

    Directory of Open Access Journals (Sweden)

    Anand Kumar B

    2003-03-01

    Full Text Available A total of one hundred patients (75 males and 25 females age ranged from 17-65 years with genital lesions attending the STD clinic of Bowring and LC Hospitals Bangalore constituted the study group. Based on clinical features, the study groups were classified as syphilis (39, chancroid (30, herpes genitolis (13, condylomato lato (9, LGV (7t condylomata acuminata (5, genital scabies (3, granuloma inguinole (2 and genital candidiasis (1. In 68% microbiological findings confirmed the clinical diagnosis. Of the 100 cases 13% and 2% were positive for HIV antibodies and HbsAg respectively.

  10. Studies in Rheoencephalography (REG

    Directory of Open Access Journals (Sweden)

    Michael Bodo

    2010-01-01

    Full Text Available This article presents an overview of rheoencephalography (REG – electrical impedance measurements of the brain – and summarizes past and ongoing research to develop medical applications of REG for neuro-critical care and for primary prevention of stroke and cardiovascular disease. The availability of advanced electronics and computation has opened up the potential for use of REG technology as a noninvasive, continuous and inexpensive brain monitor for military and civilian applications. The clinical background information presented here introduces physiological and clinical environments where REG has potential for use in research and clinical settings. REG studies over the past three decades have involved in vitro and in vivo groups (animal and human, including more than 1500 measurements and related electronic and computational results and practical applications. In vitro studies helped researchers understand the flow/volume relationship between Doppler ultrasound and electrical impedance signals and supported development of REG data processing methods. In animal studies, REG was used to monitor the lower limit of cerebral blood flow (CBF autoregulation (AR using a newly developed algorithm. These animal studies also confirmed correlations between REG and measurements of carotid flow (CF and intracranial pressure (ICP. Human studies confirmed the applicability of REG for detecting cerebrovascular alteration, demonstrating the usefulness of REG in the field of stroke/cardio-vascular disease prevention. In these studies, REG was compared to known stroke risk factors and to results obtained using carotid ultrasound measurements. An intelligent REG system (Cerberus has been developed for primary stroke prevention. In these studies, the biologically relevant variables of the REG signal were pulse amplitude (minimum – maximum distance and duration of the anacrotic (rising portion of the REG pulse wave. The principal limitation of REG for

  11. Studies in neuroendocrine pharmacology

    Science.gov (United States)

    Maickel, R. P.

    1976-01-01

    The expertise and facilities available within the Medical Sciences Program section on Pharmacology were used along with informational input from various NASA sources to study areas relevant to the manned space effort. Topics discussed include effects of drugs on deprivation-induced fluid consumption, brain biogenic amines, biochemical responses to stressful stimuli, biochemical and behavioral pharmacology of amphetamines, biochemical and pharmacological studies of analogues to biologically active indole compounds, chemical pharmacology: drug metabolism and disposition, toxicology, and chemical methodology. Appendices include a bibliography, and papers submitted for publication or already published.

  12. Clinical Nursing Records Study

    Science.gov (United States)

    1991-08-01

    effectiveness codes can be used for all controlled substances as well as PRN medications other than controlled substances, e.g., milk of magnesia...7C 270 7.,TAL 1 C,.. .C 1c((.C Uht [- IF MISSING UBSF’VATILNS 576 1-26 Table 27 CLINICAL NURSING RECORDS STUDY "OVERPRINTING THE NURSING DIAGNOSES ONTO

  13. Study of Meteoritic Inclusion

    DEFF Research Database (Denmark)

    Olsen, Mia Bjørg Stolberg

    as astronomical observation of starforming regions and exoplanets provide a framework for understanding star-formation processes and the evolution of planetary systems, but offer no direct insight into the earliest solar system. This necessary and complementary information can be obtained through the study...

  14. Fall 1982 Retention Study.

    Science.gov (United States)

    Peralta Community Coll. District, Oakland, CA. Office of Research, Planning and Development.

    In fall 1982, a study was conducted in the Peralta Community College District (PCCD) using withdrawal and grade distribution data to analyze student retention patterns. Successful retention rates were based on the percentage of students who received a passing grade, while total retention rates were based on the percentage of students who received…

  15. Area Studies: China.

    Science.gov (United States)

    Blouin, Virginia; And Others

    The guide outlines a course of study for elementary students on the history, geography, language, and general culture of China. Course objectives are to identify the major mountains, the major cities, and the types of climate affecting each region of China; locate and record on a time line the important events in the development of Chinese…

  16. Studying Aid: Some Methods

    NARCIS (Netherlands)

    D.R. Gasper (Des)

    2003-01-01

    textabstractINVESTIGATING IDEAS, IDEOLOGIES AND PRACTICES This paper presents some methods for trying to make sense of international aid and of its study.1 Some of the methods may be deemed ethnographic; the others are important partners to them, but rather different. In the course of discussing

  17. An exploratory study

    African Journals Online (AJOL)

    and innovation involving higher levels of uncertainty and complexity as a means of achieving personal fulfilment.” In consideration of the purpose of this study, it is also important to distinguish between education and training. According to Feinstein, Mann and Corsun (2002: 739), education is a process whereby knowledge ...

  18. Everglades Environmental Study Units.

    Science.gov (United States)

    Florida State Dept. of Education, Tallahassee. Office of Environment Education.

    These environmental study units consist of four modules and a tape-slide presentation on the Everglades National Park. Although not required for completion of the modules, the slide-tape presentation provides a resource for orientation of teachers and parents to camping experience for school children in an environmental education program. The four…

  19. Transfer Readiness Pilot Study.

    Science.gov (United States)

    Scott-Skillman, Thelma; And Others

    The California Community Colleges (CCC) has implemented a prototype model for determining student transfer readiness as a primary means of assessing community college transfer effectiveness. This report provides definitions of transfer readiness and guidelines for colleges participating in the CCC transfer readiness study. First, a memorandum from…

  20. A Psychobiographical Case Study

    African Journals Online (AJOL)

    The secondary objective was to illustrate and test the relevance of Levinsonian theory as applied .... Levinson's theory was selected for this psychobiographical case study due to (a) its focus on the individual's entire lifespan,. (b) its amalgamation of other theories, ...... ship with an object has great meaning (as did Jobs's.

  1. CENTRE FOR CONTEMPORARY STUDIES

    Indian Academy of Sciences (India)

    ROOPA

    Venue: Seminar Hall, Centre for Contemporary Studies,. Indian Institute of Science, Bangalore 560 012. All are cordially invited. Tea/Coffee will be served at 10:30 a.m.. Jean Taylor is Professor of Mathematics Emerita of the Rutgers University and currently a visitor at the Courant Institute for Mathematical Sciences, NYU.

  2. Soil washing treatability study

    Energy Technology Data Exchange (ETDEWEB)

    Krstich, M.

    1995-12-01

    Soil washing was identified as a viable treatment process option for remediating soil at the FEMP Environmental Management Project (FEMP). Little information relative to the specific application and potential effectiveness of the soil washing process exists that applies to the types of soil at the FEMP. To properly evaluate this process option in conjunction with the ongoing FEMP Remedial Investigation/Feasibility Study (RI/FS), a treatability testing program was necessary to provide a foundation for a detailed technical evaluation of the viability of the process. In August 1991, efforts were initiated to develop a work plan and experimental design for investigating the effectiveness of soil washing on FEMP soil. In August 1992, the final Treatability Study Work Plan for Operable Unit 5: Soil Washing (DOE 1992) was issued. This document shall be referenced throughout the remainder of this report as the Treatability Study Work Plan (TSWP). The purpose of this treatability study was to generate data to support initial screening and the detailed analysis of alternatives for the Operable Unit 5 FS.

  3. To study propulsion drives

    OpenAIRE

    Rassylkin, Anton; Vodovozov, Valery

    2013-01-01

    This paper describes a test bench developed to study and monitor the propulsion drives of electric vehicles at Tallinn University of Technology. The composition and performance of the setup are explained. The charging process of the supercapacitor bank is described as an example of the test bench application. The developed simulation model of the supercapacitor bank is presented and discussed.

  4. national Case study

    African Journals Online (AJOL)

    expansive orientation to knowledge and pedagogical content knowledge is required, if quality education is to emerge. The study provides a revised conceptual framework for the Teacher. Development Network (TEDN) programme, with guidance on key elements necessary to take the programme forward in Phase 2.

  5. Southern Appalachian Case Study

    Science.gov (United States)

    Charles C. van Sickle

    1999-01-01

    The Southern Appalachian study covers a region of 37.4 million acres. Its mountains, foothills, and valleys stretch from northern Virginia and northern West Virginia to northern Georgia and Alabama. When Native Americans came to the region, forests dominated the landscape and they still do, covering 70% of the land (Figure 32.1). Terrain characteristics are...

  6. A retrospective study

    African Journals Online (AJOL)

    All children with autistic spectrum disorder (ASD) will manifest auditory-related dysfunction ... neurological disorders, as results were obtained in only 27.5% of the study sample; however, it remains the gold standard in paediatric hearing testing to evaluate ..... The MIT Encyclopedia of Communication Disorders. Cambridge,.

  7. Resources for Women's Studies.

    Science.gov (United States)

    Ridinger, Robert B.

    Over 120 bibliographies and other reference sources relevant to women's studies are identified in this annotated listing. Subjects include feminist scholarship, women in management, popular culture, autobiographies, other cultures and countries, history, lesbian women, women's education, the arts, politics, and rape. In addition to author, title,…

  8. A qualitative study

    African Journals Online (AJOL)

    Methods. We conducted a cross-sectional qualitative study using .... qualitative data analysis. .... there was research being done on a new diagnostic test for ... understanding of the cultural and social issues affecting patients ... shared her sentiment that expatriate physicians are too ... they help Malawian students to network.

  9. Eastern Frequency Response Study

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N.W.; Shao, M.; Pajic, S.; D' Aquila, R.

    2013-05-01

    This study was specifically designed to investigate the frequency response of the Eastern Interconnection that results from large loss-of-generation events of the type targeted by the North American Electric Reliability Corp. Standard BAL-003 Frequency Response and Frequency Bias Setting (NERC 2012a), under possible future system conditions with high levels of wind generation.

  10. Advanced commercial tokamak study

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, S.L.; Dabiri, A.E.; Keeton, D.C.; Brown, T.G.; Bussell, G.T.

    1985-12-01

    Advanced commercial tokamak studies were performed by the Fusion Engineering Design Center (FEDC) as a participant in the Tokamak Power Systems Studies (TPSS) project coordinated by the Office of Fusion Energy. The FEDC studies addressed the issues of tokamak reactor cost, size, and complexity. A scoping study model was developed to determine the effect of beta on tokamak economics, and it was found that a competitive cost of electricity could be achieved at a beta of 10 to 15%. The implications of operating at a beta of up to 25% were also addressed. It was found that the economics of fusion, like those of fission, improve as unit size increases. However, small units were found to be competitive as elements of a multiplex plant, provided that unit cost and maintenance time reductions are realized for the small units. The modular tokamak configuration combined several new approaches to develop a less complex and lower cost reactor. The modular design combines the toroidal field coil with the reactor structure, locates the primary vacuum boundary at the reactor cell wall, and uses a vertical assembly and maintenance approach. 12 refs., 19 figs.

  11. A qualitative study

    African Journals Online (AJOL)

    In post-stroke patients, impairment of quality of life (QOL) has been associated with functional impairment, age, ... studies from Nigeria and Tanzania have reported on post-stroke QOL. Background. Approximately 90% of .... (nurses') perceptions affect implementation and utilization of FANC in Tanzania12. She argued that ...

  12. The rail diesel study

    Energy Technology Data Exchange (ETDEWEB)

    Halder, M. [Swiss Federal Railways, Bern (Switzerland). Rail Environmental Center; Schwarz, H. [Deutsche Bahn AC, Berlin (Germany). Railway Environmental Centre; Kollamthodi, S. [AEA Technology Environment, Didcot (United Kingdom)

    2006-07-01

    This rail diesel study examined measures and strategies to reduce nitrogen oxide (NO{sub x}) and particulate matter (PM{sub 10}) emissions from the European rail fleet. The study examined the feasibility of using operational and technical measures to the current diesel-based fleet, and in addition provided cost benefit estimates for applying various strategies to the existing fleet over the next 5 years. The study reviewed the use of diesel traction units and developed forecast projections for the uptake and use of diesel traction units up to the year 2020. Technical and operational measures for reducing emissions were assessed, along with life cycle costs. Air quality modelling was conducted to estimate the contributions of different types of railway locations in relation to ambient concentrations of nitrogen dioxide (NO{sub 2}) and particulate matter. Results of the study suggested that emission reduction technologies emissions limits will be achieved by using internal engine design measures rather than through the use of exhaust after-treatment equipment. It was concluded that modern diesel combustion technology, optimized air cooling, and improved injection and charging technology will be used in combination with low sulfur fuel to reduce emissions. However, engine and vehicle purchase costs will increase by between 5 and 13 per cent, while maintenance expenditure is expected to increase by up to 10 per cent. 5 figs.

  13. 425 Case study

    African Journals Online (AJOL)

    Marinda

    Case Study. 29. SAJAA 2009;15(3) • Jun/Jul. Anaesthesia management of acute aortic dissection type B in Marfan syndrome complicating end-stage pregnancy a Laudanski K, MD, b Robicsek S, MD, PhD a Department of Anesthesiology and Critical Care, Beth Israel and Deaconess Hospital, Harvard Medical School, ...

  14. The Deployment Life Study

    Science.gov (United States)

    Meadows, Sarah O.; Tanielian, Terri; Karney, Benjamin; Schell, Terry; Griffin, Beth Ann; Jaycox, Lisa H.; Friedman, Esther M.; Trail, Thomas E.; Beckman, Robin; Ramchand, Rajeev; Hengstebeck, Natalie; Troxel, Wendy M.; Ayer, Lynsay; Vaughan, Christine Anne

    2017-01-01

    Abstract In 2009, RAND launched the Deployment Life Study, a longitudinal study of military families across a deployment cycle in order to assess family readiness. Family readiness refers to the state of being prepared to effectively navigate the challenges of daily living experienced in the unique context of military service. The study surveyed families at frequent intervals throughout a complete deployment cycle---before a service member deploys (sometimes months before), during the actual deployment, and after the service member returns (possibly a year or more after she or he redeployed). It assessed a number of outcomes over time, including: the quality of marital and parental relationships the psychological, behavioral, and physical health of family members child and teen well-being (e.g., emotional, behavioral, social, and academic) military integration (e.g., attitudes toward military service, retention intentions). This culminating paper briefly reviews the study design and data collection procedures, presents results from analyses of the longitudinal data collected from some 2,700 military families, and offers recommendations for programs and future research related to military families. The research was jointly sponsored by the Office of the Surgeon General, U.S. Army, and by the Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury. PMID:28845345

  15. The Study of Butterflies

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 5. The Study of Butterflies - Intra-specific Variation. Peter Smetacek. Series Article Volume 6 Issue 5 May 2001 pp 8-15. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/006/05/0008-0015 ...

  16. A life studying life

    OpenAIRE

    Duca, Edward

    2014-01-01

    Prof. Patrick J. Schembri lives for biology. His long career has brought him in touch with an endless list of creatures that include fish, beautiful white coral, sharks, limpets, crabs, and ancient snails. The Editor met up with Schembri to find out more about the life around Malta. http://www.um.edu.mt/think/a-life-studying-life/

  17. Thinking With Disability Studies

    Directory of Open Access Journals (Sweden)

    Nirmala Erevelles

    2014-03-01

    Full Text Available In this essay, I offer tentative ruminations about the possibilities/challenges of theory and praxis in the field of disability studies. I begin the essay by thinking through my own positionality as a non-disabled woman of color scholar/ally in the field. Cautiously situating myself in a location of outsider-within (Hill-Collins,1998, I explore how disability studies is disruptive of any boundaries that claim to police distinctions between disabled/non-disabled subject positions. Noting the dangers of claiming that everyone is disabled at some historical moment, I propose instead a relational analysis to engage the materiality of disability at the intersections of race, class, gender, nation, and sexual identity within specific historical contexts and discuss the complicated impasses that continue to plague disability studies at these intersections. I conclude the essay by recognizing the labor of scholar/activists in the field who call for a committed politics of accountability and access via disability justice.    Keywords: disability studies, historical materialism, identity politics and intersectionality, disability justice, politics of accountability/allyship

  18. Cephradine antacids interaction studies.

    Science.gov (United States)

    Arayne, M Saeed; Sultana, Najma; Afzal, M

    2007-07-01

    The present work comprises of interaction studies of cephradine with antacids. Cephradine is included among the first generation cephalosporin, which is active against a wide range of Gram positive and Gram-negative bacteria including penicillinase-producing staphylococci. Since the presence of complexing ligand may affect the bioavailability of a drug in blood or tissues, therefore, in order to study the probable interaction of cephradine with antacids all the reaction conditions were simulated to natural environments. Antacids are commonly used in patients complaining of GI irritations. The behavior of cephradine in presence of seven antacids i.e., simethicone, magaldrate, magnesium carbonate, magnesium hydroxide, magnesium trisilicate, sodium bicarbonate and aluminium hydroxide was studied by using standard dissolution apparatus. Cephradine was monitored both by UV and by high performance liquid chromatography. The results revealed that antacids containing polyvalent cations retarded the in vitro availability of cephradine. Moreover, these studies indicated that cephradine was strongly adsorbed on antacids; magnesium trisilicate and simeco tablets (powdered) exhibited relatively higher adsorption capacities.

  19. Army Training Study: Administration.

    Science.gov (United States)

    1978-08-08

    focus on study objectives and Army of the 80’s. b. Ensure training programs are compatible with new equipment. c. Visualize our strategy as designing for...tasks that the unit is expected to be able to perform ("playbook"). Annual requirements (EDRE, IG, TPI, FTX, MOBA , etc.) form the basis for the

  20. Studies in internationalization

    NARCIS (Netherlands)

    van der Wende, Marijk

    2001-01-01

    Research-based literature on new phenomena is scarce, so is the literature on the relatively new, but strongly growing, trend in internationalization, which concerns the provision of education across borders: A trend that sometimes has been identified as "moving education, not learners," Two studies