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Sample records for seepage basin 716-a

  1. Statement of Basis/Proposed Plan for the Motor Shops Seepage Basin (716-A); FINAL

    International Nuclear Information System (INIS)

    Palmer, E.

    1998-01-01

    The purpose of this plan is to describe the preferred alternative for addressing the Motor Shops Seepage Basin located at the Savannah River site in Aiken County, Aiken, South Carolina and to provide an opportunity for public input into the remedial action selection process

  2. New TNX Seepage Basin: Environmental information document

    International Nuclear Information System (INIS)

    Dunaway, J.K.W.; Johnson, W.F.; Kingley, L.E.; Simmons, R.V.; Bledsoe, H.W.

    1986-12-01

    The New TNX Seepage Basin has been in operation at the Savannah River Plant (SRP) since 1980 and is located in the southeastern section of the TNX facility. The basin receives waste from pilot scale tests conducted at TNX in support of the Defense Waste Processing Facility (DWPF) and the plant Separations area. The basin is scheduled for closure after the TNX Effluent Treatment Plant (ETP) begins operation. The basin will be closed pursuant to all applicable state and federal regulations. A statistical analysis of monitoring data indicates elevated levels of sodium and zinc in the groundwater at this site. Closure options considered for the New TNX Seepage Basin include waste removal and closure, no waste removal and closure, and no action. The two predominant pathways for human exposure to chemical contaminants are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options for the New TNX Seepage Basin. Cost estimates for each closure option at the basin have also been prepared. An evaluation of the environmental impacts from the New TNX Seepage Basin indicate that the relative risks to human health and ecosystems for the postulated closure options are low. The transport of six chemical and one radionuclide constituents through the environmental pathways from the basin were modeled. The maximum chemical carcinogenic risk and the noncarcinogenic risk for the groundwater pathways were from exposure to trichloromethane and nitrate

  3. H-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    1992-09-01

    During second quarter 1992, tritium, nitrate, nonvolatile beta, total alpha-emitting radium (radium-224 and radium-226), gross alpha, mercury, lead, tetrachloroethylene, arsenic, and cadmium exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the H-Area Seepage Basins (HASB) at the Savannah River Plant. This report gives the results of the analyses of groundwater from the H-Area Seepage Basin

  4. Geochemical Modeling Of F Area Seepage Basin Composition And Variability

    International Nuclear Information System (INIS)

    Millings, M.; Denham, M.; Looney, B.

    2012-01-01

    From the 1950s through 1989, the F Area Seepage Basins at the Savannah River Site (SRS) received low level radioactive wastes resulting from processing nuclear materials. Discharges of process wastes to the F Area Seepage Basins followed by subsequent mixing processes within the basins and eventual infiltration into the subsurface resulted in contamination of the underlying vadose zone and downgradient groundwater. For simulating contaminant behavior and subsurface transport, a quantitative understanding of the interrelated discharge-mixing-infiltration system along with the resulting chemistry of fluids entering the subsurface is needed. An example of this need emerged as the F Area Seepage Basins was selected as a key case study demonstration site for the Advanced Simulation Capability for Environmental Management (ASCEM) Program. This modeling evaluation explored the importance of the wide variability in bulk wastewater chemistry as it propagated through the basins. The results are intended to generally improve and refine the conceptualization of infiltration of chemical wastes from seepage basins receiving variable waste streams and to specifically support the ASCEM case study model for the F Area Seepage Basins. Specific goals of this work included: (1) develop a technically-based 'charge-balanced' nominal source term chemistry for water infiltrating into the subsurface during basin operations, (2) estimate the nature of short term and long term variability in infiltrating water to support scenario development for uncertainty quantification (i.e., UQ analysis), (3) identify key geochemical factors that control overall basin water chemistry and the projected variability/stability, and (4) link wastewater chemistry to the subsurface based on monitoring well data. Results from this study provide data and understanding that can be used in further modeling efforts of the F Area groundwater plume. As identified in this study, key geochemical factors affecting basin

  5. H-Area Seepage Basin (H-HWMF): Fourth quarterly 1989, groundwater quality assessment report

    Energy Technology Data Exchange (ETDEWEB)

    1990-03-01

    During the fourth quarter of 1989 the wells which make up the H-Area Seepage Basins (H-HWMF){sup 1} monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Seepage Basins are tritium, nitrate, mercury, gross alpha, and total radium.

  6. H-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    Thompson, C.Y.

    1992-06-01

    During first quarter 1992, tritium, nitrate, nonvolatile beta, total alpha-emitting radium (radium-224 and radium-226), gross alpha, antimony, mercury, lead, tetrachloroethylene, arsenic, and cadmium exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the H-Area Seepage Basins (HASB) at the Savannah River Site. This report presents and discusses the groundwater monitoring results in the H-Area for first quarter 1992

  7. Operating history and environmental effects of seepage basins in chemical-separations areas of the Savannah River Plant

    International Nuclear Information System (INIS)

    Fenimore, J.W.; Horton, J.H.

    1973-01-01

    This report summarizes the history of operation and monitoring of the earthen seepage basins, presents results of a comprehensive study of radionuclide distribution in groundwater downgradient from the basins, and evaluates past performance and possible future alternatives for these basins

  8. Old TNX Seepage Basin: Environmental information document

    International Nuclear Information System (INIS)

    Dunaway, J.K.; Johnson, W.F.; Kingley, L.E.; Simmons, R.V.; Bledsoe, H.W.; Smith, J.A.

    1986-12-01

    This document provides environmental information on postulated closure options for the Old TNX Seepage Basin at the Savannah River Plant and was developed as background technical documentation for the Department of Energy's proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (40 CFR 1500-1508). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to be used as a regulatory closure plan or other regulatory document to comply with required federal or state environmental regulations

  9. Toxicity of Water Samples Collected in the Vicinity of F and H Seepage Basin 1990-1995

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L. [Westinghouse Savannah River Company, AIKEN, SC (United States); Bowers, B.

    1996-09-01

    Water and contaminants from the F- and H-Area Seepage Basins outcrop as shallow groundwater seeps down gradient from the basins. In 1990, 1991, 1993, 1994, and 1995, toxicity tests were performed on water collected from a number of these seeps, as well as from several locations in Fourmile Branch and several uncontaminated reference locations.

  10. Cadmium geochemistry in soil and groundwater at the F and H Seepage Basins

    International Nuclear Information System (INIS)

    Serkiz, S.M.; Johnson, W.H.

    1994-10-01

    For 33 years, low activity liquid wastes from the chemical separation areas at the US Department of Energy's Savannah River Site were disposed of in unlined seepage basins. This disposal practice was discontinued in 1988. At that time, the basins were drained and a low permeability cover system was placed over the basins. In the summer of 1993, soil and associated pore water samples of widely varying groundwater chemistries and contaminant concentrations were collected from the region downgradient of these basins using cone penetrometer technology. Analysis of these samples using inductively coupled plasma - mass spectrometry has allowed the investigation of cadmium partitioning between the aqueous phase and soil surfaces at this site. The distribution of cadmium was examined with respect to the solution and soil chemistry and aqueous-phase chemical speciation modeling. Cadmium was detected in 35 of 53 aqueous samples from the F- and H-Area Seepage Basins (FHSB). Porewater concentration were found to vary from 0.48 to 23.5 μg 1 -1 , with a mean concentration of 3.1 ± 4.3 μg 1 -1 . Based on the 43 of 86 soil samples for which cadmium was detected, the concentration in the soil ranged 88.5 to 1090 μg kg -1 . The mean soil concentration was 214 ± 168 μg kg -1 . This concentration is not significantly different from the concentrations observed in two upgradient soil samples collected from the same lithologic unit. The concentrations from these samples were 293 ± 214 and 431 ± 293 μg kg -1

  11. Levels of radioactivity in fish from streams near F-Area and H-Area seepage basins

    International Nuclear Information System (INIS)

    Murphy, C.E. Jr.; Loehle, C.

    1991-05-01

    This report summarizes results of recent analyses of radioactivity in fish from SRS streams near the F-Area and H-Area seepage basins. Fish were collected from headwater areas of Four Mile Creek and Pen Branch, from just below the H-Area seepage basin, and from three sites downstream in Four Mile Creek. These fish were analyzed for gross alpha and gross beta radioactivity using standard EPA methods. Levels of gross alpha and nonvolatile beta radioactivity in fish were found to be comparable to levels previously reported for these sites. Gross alpha activity was not found to be influenced by Separations Area discharges. Nonvolatile beta activity was higher in the nonvolatile beta activity was attributable to Cs-137 and K-40. The dosimetric consequences of consuming fish from this area were found to be well below DOE guidelines

  12. Radionuclide inventories for the F- and H-area seepage basin groundwater plumes

    Energy Technology Data Exchange (ETDEWEB)

    Hiergesell, Robert A [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kubilius, Walter P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-01

    Within the General Separations Areas (GSA) at the Savannah River Site (SRS), significant inventories of radionuclides exist within two major groundwater contamination plumes that are emanating from the F- and H-Area seepage basins. These radionuclides are moving slowly with groundwater migration, albeit more slowly due to interaction with the soil and aquifer matrix material. The purpose of this investigation is to quantify the activity of radionuclides associated with the pore water component of the groundwater plumes. The scope of this effort included evaluation of all groundwater sample analyses obtained from the wells that have been established by the Environmental Compliance & Area Completion Projects (EC&ACP) Department at SRS to monitor groundwater contamination emanating from the F- and H-Area Seepage Basins. Using this data, generalized groundwater plume maps for the radionuclides that occur in elevated concentrations (Am-241, Cm-243/244, Cs-137, I-129, Ni-63, Ra-226/228, Sr-90, Tc-99, U-233/234, U-235 and U-238) were generated and utilized to calculate both the volume of contaminated groundwater and the representative concentration of each radionuclide associated with different plume concentration zones.

  13. F-Area Seepage Basins Groundwater Monitoring Report: Volume 1, Third and fourth quarters 1994

    International Nuclear Information System (INIS)

    Chase, J.A.

    1994-03-01

    Isoconcentration/isoactivity maps included in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units. Geologic cross sections indicate both the extent and depth of contamination of the primary contaminants in all of the hydrostratigraphic units during the second half of 1994. Water-level maps indicate that the groundwater flow rates and directions at the F-Area Seepage Basins have remained relatively constant since the basins ceased to be active in 1988

  14. H-Area Seepage Basins Groundwater Monitoring Report: Volume 1, Third and Fourth quarters 1994

    International Nuclear Information System (INIS)

    Chase, J.A.

    1994-03-01

    Isoconcentration/isocactivity maps included in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units during the second half of 1994. Geologic cross sections indicate both the extent and depth of contamination of the primary contaminants in all of the hydrostratigraphic units during the second half of 1994. Water-level maps indicate that the groundwater flow rates and directions at the H-Area Seepage Basins have remained relatively constant since the basins ceased to be active in 1988

  15. F-Area Seepage Basins groundwater monitoring report -- third and fourth quarters 1993

    International Nuclear Information System (INIS)

    Butler, C.T.

    1994-03-01

    During the second half of 1993, the groundwater at the F-Area Seepage Basins (FASB) was monitored in compliance with Module 3, Section C, of South Carolina Hazardous Waste Permit SC1-890-008-989, effective November 2, 1992. The monitoring well network is composed of 87 FSB wells screened in the three hydrostratigraphic units that make up the uppermost aquifer beneath the FASB. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the F-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Beginning in the first quarter of 1993, the standard for comparison became the SCDHEC Groundwater Protection Standard (GWPS) specified in the approved F-Area Seepage Basins Part B permit. Currently and historically, gross alpha, nitrate, nonvolatile beta, and tritium are among the primary constituents to exceed standards. Numerous other radionuclides and hazardous constituents also exceeded the GWPS in the groundwater at the FASB during the second half of 1993, notably aluminum, iodine-129, and zinc. The elevated constituents are found primarily in Aquifer Zone 2B 2 and Aquifer Zone 2B 1 wells. However, several Aquifer Unit 2A wells also contain elevated levels of constituents. Isoconcentration/isoactivity maps included in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units. Water-level maps indicate that the groundwater flow rates and directions at the FASB have remained relatively constant since the basins ceased to be active in 1988

  16. F-Area Seepage Basins: Environmental information document

    International Nuclear Information System (INIS)

    Corbo, P.; Killian, T.H.; Kolb, N.L.; Marine, I.W.

    1986-12-01

    This document provides environmental information on postulated closure options for the F-Area Seepage Basins at the Savannah River Plant and was developed as background technical documentation for the Department of Energy's proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (40 CFR 1502.22). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to represent or be used as a regulatory closure plan or other regulatory sufficient document. Technical assistance in the environmental analyses of waste site closures was provided by Clemson University; GeoTrans, Inc.; JBF Associates, Inc.; S.S. Papadopulos and Associates Inc.; Radiological Assessments Corporation; Rogers and Associates Engineering Corporation; Science Applications International Corporation; C.B. Shedrow Environmental Consultants, Inc.; Exploration Software; and Verbatim Typing and Editing

  17. Effects of outcropping groundwater from the F- and H-Area seepage basins on the distribution of fish in Four Mile Creek

    International Nuclear Information System (INIS)

    Paller, M.H.; Storey, C.

    1990-10-01

    Four Mile Creek was electrofished during June 26--July 2, 1990 to assess the impacts of outcropping ground water form the F- and H-Area Seepage Basins on fish abundance and distribution. Number of fish species and total catch were comparable at sample stations upstream from and downstream from the outcropping zone in Four Mile Creek. Species number and composition downstream from the outcropping zone in Four Mile Creek were similar to species number and composition in unimpacted portions of Pen Branch, Steel Creek, and Meyers Branch. These findings indicate that seepage basin outcropping was not adversely affecting the Four Mile Creek fish community. 5 refs., 3 figs., 4 tabs

  18. Uranium geochemistry in soil and groundwater at the F and H seepage basins

    International Nuclear Information System (INIS)

    Serkiz, S.M.; Johnson, W.H.

    1994-09-01

    For 33 years, low activity liquid wastes from the chemical separation areas at the U.S. Department of Energy's Savannah River Site were disposed of in unlined seepage basins. Soil and associated pore water samples of widely varying groundwater chemistries and contaminant concentrations were collected from the region downgradient of these basins using cone penetrometer technology. Analysis of samples using inductively coupled plasma - mass spectrometry has allowed the investigation of uranium partitioning between the aqueous phase and soil surfaces at this site. The distribution of uranium was examined with respect to the solution and soil chemistry (e.g., pH, redox potential, cation and contaminant concentration) and aqueous-phase chemical speciation modeling. The uranium soil source term at the F- and H-Area Seepage Basins (FHSB) is much smaller than has been used in previous modeling efforts. This should result in a much shorter remediation time and a greater effectiveness of a pump-and-treat design than previously predicted. Distribution coefficients at the (FHSB) were found to vary between 1.2 to 34,000 1 kg -1 for uranium. Differences in sorption of these elements can be explained primarily by changes in aqueous pH and the associated change in soil surface charge. Sorption models were fit directly to sorption isotherms from field samples. All models underestimated the fraction of uranium bound at low aqueous uranium concentrations. Linear models overestimated bound uranium at locations where the aqueous concentration was greater than 500 ppb. Mechanistic models provided a much better estimate of the bound uranium concentrations, especially at high aqueous concentrations. Since a large fraction of the uranium at the site is associated with the low-pH portion of the plume, consideration should be given to pumping water from the lowest pH portions of the plume in the F-Area

  19. Percolation testing at the F- and H-Area Seepage Basins

    International Nuclear Information System (INIS)

    McHood, M.D.

    1993-01-01

    The design of the F- and H-Area Seepage Basin contaminated groundwater remediation system requires information from multiple well pump tests (Reference 1). Soil percolation rates are needed in order to support the multiple well pump test planning. The objective of this task was to determine characteristic percolation rates for soils in four select areas where infiltration galleries are proposed. These infiltration galleries will be temporary installations built on the ground surface and used to disposes of water from the multiple well pump tests. A procedure defining the specific work process for collecting percolation rate data is contained in Appendix 3. Results from these percolation tests will be used in the design of infiltration galleries for the disposal of well water extracted during the multiple well pump tests

  20. R Reactor seepage basins soil moisture and resistivity field investigation using cone penetrometer technology, Savannah River Site, Aiken, South Carolina

    International Nuclear Information System (INIS)

    Harris, M.K.

    2000-01-01

    The focus of this report is the summer 1999 investigation of the shallow groundwater system using cone penetrometer technology characterization methods to determine if the water table is perched beneath the R Reactor Seepage Basins (RRSBs)

  1. Removal Site Evaluation Report to the C-Reactor Seepage Basins (904-066, -067 and -068G)

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, E.R. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1997-07-01

    Removal Site Evaluation Reports are prepared in accordance with Section 300.410 of the National Contingency Plan (NCP) and Section X of the Federal Facility Agreement (FFA). The C-Reactor Seepage Basins (904-066G,-067G,-068G) are listed in Appendix C, Resource Conservation and Recovery Act (RCRA)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Units List, of the FFA. The purpose of this investigation is to report information concerning conditions at this unit sufficient to assess the threat (if any) posed to human health and the environment and to determine the need for additional CERCLA action. The scope of the investigation included a review of past survey and investigation data, the files, and a visit to the unit.Through this investigation unacceptable conditions of radioactive contaminant uptake in on-site vegetation were identified. This may have resulted in probable contaminant migration and become introduced into the local ecological food chain. As a result, the SRS will initiate a time critical removal action in accordance with Section 300.415 of the NCP and FFA Section XIV to remove, treat (if required), and dispose of contaminated vegetation from the C-Reactor Seepage Basins. Erosion in the affected areas will be managed by an approved erosion control plan. further remediation of this unit will be conducted in accordance with the FFA.

  2. Removal Site Evaluation Report to the C-Reactor Seepage Basins (904-066, -067 and -068G)

    International Nuclear Information System (INIS)

    Palmer, E.R.

    1997-07-01

    Removal Site Evaluation Reports are prepared in accordance with Section 300.410 of the National Contingency Plan (NCP) and Section X of the Federal Facility Agreement (FFA). The C-Reactor Seepage Basins (904-066G,-067G,-068G) are listed in Appendix C, Resource Conservation and Recovery Act (RCRA)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Units List, of the FFA. The purpose of this investigation is to report information concerning conditions at this unit sufficient to assess the threat (if any) posed to human health and the environment and to determine the need for additional CERCLA action. The scope of the investigation included a review of past survey and investigation data, the files, and a visit to the unit.Through this investigation unacceptable conditions of radioactive contaminant uptake in on-site vegetation were identified. This may have resulted in probable contaminant migration and become introduced into the local ecological food chain. As a result, the SRS will initiate a time critical removal action in accordance with Section 300.415 of the NCP and FFA Section XIV to remove, treat (if required), and dispose of contaminated vegetation from the C-Reactor Seepage Basins. Erosion in the affected areas will be managed by an approved erosion control plan. further remediation of this unit will be conducted in accordance with the FFA

  3. Surface Water Transport for the F/H Area Seepage Basins Groundwater Program

    International Nuclear Information System (INIS)

    Chen, Kuo-Fu.

    1995-01-01

    The contribution of the F- and H-Area Seepage Basins (FHSBs) tritium releases to the tritium concentration in the Savannah River are presented in this report. WASP5 was used to simulate surface water transport for tritium releases from the FHSBs. The WASP5 model was qualified with the 1993 tritium measurements at US Highway 301. The tritium concentrations in Fourmile Branch and the Savannah River were calculated for tritium releases from FHSBs. The calculated tritium concentrations above normal environmental background in the Savannah River, resulting from FHSBs releases, drop from 1.25 pCi/ml (<10% of EPA Drinking Water Guide) in 1995 to 0.0056 pCi/ml in 2045

  4. Seepage Calibration Model and Seepage Testing Data

    International Nuclear Information System (INIS)

    Dixon, P.

    2004-01-01

    of the parameters as a result of spatial variability; (6) to evaluate prediction uncertainty based on linear uncertainty-propagation analyses and Monte Carlo simulations; (7) to validate the SCM during model development, and validate using the post-development activities outlined in the Technical Work Plan (TWP); (8) to provide the technical basis for the resolution of unconfirmed issues previously labeled ''to be verified'' (TBV); and (9) to provide the basis for a screening argument for certain seepage-related features, events, and processes (FEPs)

  5. Seepage Calibration Model and Seepage Testing Data

    Energy Technology Data Exchange (ETDEWEB)

    S. Finsterle

    2004-09-02

    The purpose of this Model Report is to document the Seepage Calibration Model (SCM). The SCM was developed (1) to establish the conceptual basis for the Seepage Model for Performance Assessment (SMPA), and (2) to derive seepage-relevant, model-related parameters and their distributions for use in the SMPA and seepage abstraction in support of the Total System Performance Assessment for License Application (TSPA-LA). This Model Report has been revised in response to a comprehensive, regulatory-focused evaluation performed by the Regulatory Integration Team [''Technical Work Plan for: Regulatory Integration Evaluation of Analysis and Model Reports Supporting the TSPA-LA'' (BSC 2004 [DIRS 169653])]. The SCM is intended to be used only within this Model Report for the estimation of seepage-relevant parameters through calibration of the model against seepage-rate data from liquid-release tests performed in several niches along the Exploratory Studies Facility (ESF) Main Drift and in the Cross-Drift. The SCM does not predict seepage into waste emplacement drifts under thermal or ambient conditions. Seepage predictions for waste emplacement drifts under ambient conditions will be performed with the SMPA [''Seepage Model for PA Including Drift Collapse'' (BSC 2004 [DIRS 167652])], which inherits the conceptual basis and model-related parameters from the SCM. Seepage during the thermal period is examined separately in the Thermal Hydrologic (TH) Seepage Model [see ''Drift-Scale Coupled Processes (DST and TH Seepage) Models'' (BSC 2004 [DIRS 170338])]. The scope of this work is (1) to evaluate seepage rates measured during liquid-release experiments performed in several niches in the Exploratory Studies Facility (ESF) and in the Cross-Drift, which was excavated for enhanced characterization of the repository block (ECRB); (2) to evaluate air-permeability data measured in boreholes above the niches and the Cross

  6. Seepage Calibration Model and Seepage Testing Data

    International Nuclear Information System (INIS)

    Finsterle, S.

    2004-01-01

    The purpose of this Model Report is to document the Seepage Calibration Model (SCM). The SCM was developed (1) to establish the conceptual basis for the Seepage Model for Performance Assessment (SMPA), and (2) to derive seepage-relevant, model-related parameters and their distributions for use in the SMPA and seepage abstraction in support of the Total System Performance Assessment for License Application (TSPA-LA). This Model Report has been revised in response to a comprehensive, regulatory-focused evaluation performed by the Regulatory Integration Team [''Technical Work Plan for: Regulatory Integration Evaluation of Analysis and Model Reports Supporting the TSPA-LA'' (BSC 2004 [DIRS 169653])]. The SCM is intended to be used only within this Model Report for the estimation of seepage-relevant parameters through calibration of the model against seepage-rate data from liquid-release tests performed in several niches along the Exploratory Studies Facility (ESF) Main Drift and in the Cross-Drift. The SCM does not predict seepage into waste emplacement drifts under thermal or ambient conditions. Seepage predictions for waste emplacement drifts under ambient conditions will be performed with the SMPA [''Seepage Model for PA Including Drift Collapse'' (BSC 2004 [DIRS 167652])], which inherits the conceptual basis and model-related parameters from the SCM. Seepage during the thermal period is examined separately in the Thermal Hydrologic (TH) Seepage Model [see ''Drift-Scale Coupled Processes (DST and TH Seepage) Models'' (BSC 2004 [DIRS 170338])]. The scope of this work is (1) to evaluate seepage rates measured during liquid-release experiments performed in several niches in the Exploratory Studies Facility (ESF) and in the Cross-Drift, which was excavated for enhanced characterization of the repository block (ECRB); (2) to evaluate air-permeability data measured in boreholes above the niches and the Cross-Drift to obtain the permeability structure for the seepage model

  7. Vegetation concentration and inventory of metals and radionuclides in the old F-area seepage basin, 904-49G

    International Nuclear Information System (INIS)

    Murphy, C.E. Jr.

    1994-01-01

    Measured concentrations of radionuclides and toxic metals are used to calculate the total inventory of in the vegetation growing on the Old F-Area Seepage Basin. Air concentrations and inhalation doses from exposure to smoke from burning the vegetation are calculated to evaluate the effect of open air burning. Radionuclide inventory is one order of magnitude (10 x) less than those necessary to produce a 1 mrem dose. Air concentrations of toxic metals are less than one third the permissible occupational dose

  8. Oil seepage detection technique as a tool to hydrocarbon prospecting in offshore Campos Basin-Brazil; Deteccao de exsudacoes de oleo como uma ferramenta de prospeccao de hidrocarbonetos na regiao maritima da Bacia de Campos - Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Castilho, Jose G.; Brito, Ademilson F. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Modelagem de Bacias (LAB2M); Landau, Luiz [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Metodos Computacionais em Engenharia (LAMCE)

    2004-07-01

    With a proven capacity to identify oil slicks in offshore regions, RADARSAT-1 imagery can be useful for oil exploration purposes. The paper discusses the seepage detection method at Campos Basin, offshore Rio de Janeiro State, which is responsible for 80% of the Brazilian production of oil and gas. It is known that the horizontal migration of petroleum can occurs over tens or even hundreds of kilometers, where the source rock placed in more deep locations can be linked with shallow reservoirs or traps and even reach the ocean. It means that seepage can provide information for risking petroleum charge at basin scales, and cannot have a direct relation with the geographical position of the interpreted seeps and possible filled prospects. A good understanding of the geology, and hence the petroleum systems of a basin is the key to use seepage in exploration. The work is divided into three main steps. First step were select oil seepages interpreted at Campos Basin where is found several giant petroleum fields. Second, the geology of the study area and its structural and stratigraphic features were analyzed, in order to identify possible migration pathways related to faults generated by halokinesis. Another important aspect is the presence of 'windows' or ducts in the evaporates beds allowing the contact between the section that contains source rocks and the turbidities reservoirs, that contain the majority of the oil discovers. All these features were interpreted based on a regional dip seismic line (203 - 76), and a geologic cross section with E-W orientation, showing the structure of the Marlim Field. Finally, all the information was integrated in a Geographical Information System (GIS), and then analyzed in an interdisciplinary environment, with the intention to link possible routes of oil migration to post-evaporites reservoirs or to interpreted seeps. (author)

  9. F/H seepage basin groundwater influent, effluent, precipitated sludge characterization task technical plan

    International Nuclear Information System (INIS)

    Siler, J.L.

    1993-01-01

    A treatability study to support the development of a remediation system which would reduce the contaminant levels in groundwater removed from the aquifers in the vicinity of the F/H seepage basins and southwest of the Mixed Waste Management Facility (MWMF) at the Savannah River facility was conducted. Proposed changes in the remediation system require an additional study to determine whether precipitated sludge generated from the proposed remediation system will be hazardous as defined by RCRA. Several contaminants, such as lead and mercury, are above the groundwater protection standards. The presence of radionuclides and other contaminants in the sludge does not present a problem provided that the sludge can pass the Toxicity Characteristic Leaching Procedure (TCLP) test. The study has been developed in such a manner as to cover the possible range of treatment options that may be used

  10. Chemical Properties of Pore Water and Sediment at Three Wetland Sites Near the F- and H-Area Seepage Basins, Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Friday, G.P.

    2001-05-15

    In 1980, vegetative stress and arboreal mortality in wetland plant communities down-gradient from the F- and H-Area seepage basins were detected using aerial imagery. By 1988, approximately six acres in H-Area and four acres in F-Area had been adversely impacted. Today, wetland plant communities have become well established at the H-Area tree-kill zone.

  11. A tube seepage meter for in situ measurement of seepage rate and groundwater sampling

    Science.gov (United States)

    Solder, John; Gilmore, Troy E.; Genereux, David P.; Solomon, D. Kip

    2016-01-01

    We designed and evaluated a “tube seepage meter” for point measurements of vertical seepage rates (q), collecting groundwater samples, and estimating vertical hydraulic conductivity (K) in streambeds. Laboratory testing in artificial streambeds show that seepage rates from the tube seepage meter agreed well with expected values. Results of field testing of the tube seepage meter in a sandy-bottom stream with a mean seepage rate of about 0.5 m/day agreed well with Darcian estimates (vertical hydraulic conductivity times head gradient) when averaged over multiple measurements. The uncertainties in q and K were evaluated with a Monte Carlo method and are typically 20% and 60%, respectively, for field data, and depend on the magnitude of the hydraulic gradient and the uncertainty in head measurements. The primary advantages of the tube seepage meter are its small footprint, concurrent and colocated assessments of q and K, and that it can also be configured as a self-purging groundwater-sampling device.

  12. Final Report for the Demonstration of Plasma In-situ Vitrification at the 904-65G K-Reactor Seepage Basin

    Energy Technology Data Exchange (ETDEWEB)

    Blundy, R.F. [Westinghouse Savannah River Company, AIKEN, SC (United States); Zionkowki, P.G.

    1997-12-22

    The In-situ Vitrification (ISV) process potentially offers the most stable waste-form for containment of radiologically contaminated soils while minimizing personnel contamination. This is a problem that is extensive, and at the same time unique, to the US Department of Energy`s (DOE) Weapons Complex. An earlier ISV process utilized joule heating of the soil to generate the subsurface molten glass product. However previous test work has indicated that the Savannah river Site soils (SRS) may not be entirely suitable for vitrification by joule heating due to their highly refractory nature. The concept of utilizing a plasma torch for soil remediation by in-situ vitrification has recently been developed, and laboratory test work on a 100 kW unit has indicated a potentially successful application with SRS soils. The Environmental Restoration Division (ERD) of Westinghouse Savannah River Company (WSRC) conducted the first field scale demonstration of this process at the (904-65G) K-Reactor Seepage Basin in October 1996 with the intention of determining the applicability and economics of the process for remediation of a SRS radioactive seepage basin. The demonstration was successful in completing three vitrification runs, including two consecutive runs that fused together adjacent columns of glass to form a continuous monolith. This report describes the demonstration, documents the engineering data that was obtained, summarizes the process economics and makes recommendations for future development of the process and equipment.

  13. Final Report for the Demonstration of Plasma In-situ Vitrification at the 904-65G K-Reactor Seepage Basin

    International Nuclear Information System (INIS)

    Blundy, R.F.; Zionkowki, P.G.

    1997-01-01

    The In-situ Vitrification (ISV) process potentially offers the most stable waste-form for containment of radiologically contaminated soils while minimizing personnel contamination. This is a problem that is extensive, and at the same time unique, to the US Department of Energy's (DOE) Weapons Complex. An earlier ISV process utilized joule heating of the soil to generate the subsurface molten glass product. However previous test work has indicated that the Savannah river Site soils (SRS) may not be entirely suitable for vitrification by joule heating due to their highly refractory nature. The concept of utilizing a plasma torch for soil remediation by in-situ vitrification has recently been developed, and laboratory test work on a 100 kW unit has indicated a potentially successful application with SRS soils. The Environmental Restoration Division (ERD) of Westinghouse Savannah River Company (WSRC) conducted the first field scale demonstration of this process at the (904-65G) K-Reactor Seepage Basin in October 1996 with the intention of determining the applicability and economics of the process for remediation of a SRS radioactive seepage basin. The demonstration was successful in completing three vitrification runs, including two consecutive runs that fused together adjacent columns of glass to form a continuous monolith. This report describes the demonstration, documents the engineering data that was obtained, summarizes the process economics and makes recommendations for future development of the process and equipment

  14. Seepage through a hazardous-waste trench cover

    Science.gov (United States)

    Healy, R.W.

    1989-01-01

    Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216 mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest rates occurred along the edge of the cover, where seepage was highly episodic, with 84% of the total there being traced to wetting fronts from 28 individual storms. Limitations of the zero-flux-plane method were severe enough for the method to be judged inappropriate for use in this study.Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest

  15. H-Area Seepage Basins groundwater monitoring report -- third and fourth quarters 1993

    International Nuclear Information System (INIS)

    Butler, C.T.

    1994-03-01

    During the second half of 1993, the groundwater at the H-Area Seepage Basins (HASB) was monitored in compliance with the September 30, 1992, modification of South Carolina Hazardous Waste Permit SC1-890-008-989. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the H-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Beginning first quarter 1993, the HASB's Groundwater Protection Standard (GWPS), established in Appendix 3D-A of the cited permit, became the standard for comparison. Historically as well as currently, nitrate, nonvolatile beta, and tritium have been among the primary constituents to exceed standards. Other radionuclides and hazardous constitutents also exceeded the GWPS in the groundwater at the HASB (notably aluminum, iodine-129, strontium-90, technetium-99, and zinc) during the second half of 1993. Elevated constituents were found primarily in Aquifer Zone 2B 2 and in the upper portion of Aquifer Zone 2B 1 . However, constituents exceeding standards also occurred in several wells screened in the lower portion of Aquifer Zone 2B 1 and Aquifer Unit 2A. Isoconcentration/isoactivity maps include in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units during the second half of 1993. Water-level maps indicate that the groundwater flow rates and directions at the HASB have remained relatively constant since the basins ceased to be active in 1988

  16. Effect of fluid–solid coupling on shale mechanics and seepage laws

    Directory of Open Access Journals (Sweden)

    Fuquan Song

    2018-02-01

    Full Text Available In this paper, the cores of outcropped black shale of Lower Silurian Longmaxi Fm in the Yibin area, Sichuan Basin, were taken as samples to investigate the effects of extraneous water on shale mechanics and seepage laws during the production of shale gas reservoirs. Firstly, the development of fractures in water saturated cores was observed by using a VHX-5000 optical superdepth microscope. Secondly, water, formation water and slick water, as well as the damage form and compression strength of water saturated/unsaturated cores were investigated by means of a uniaxial compression testing machine and a strain testing & analysis system. Finally, the effects of fluid–solid coupling on shale gas flowing performance in different water saturations were analyzed by using a DYQ-1 multi-function displacement device. Analysis on core components shows that the Longmaxi shale is a highly crushable reservoir with a high content of fragile minerals, so fracturing stimulation is suitable for it. Shale compression strength test reveals that the effects of deionized water, formation water and slick water on shale are different, so the compression strength of shale before being saturated is quite different from that after being saturated. Due to the existence of water, the compression strength of shale drops, so the shale can be fractured easily, more fractures are generated and thus its seepage capacity is improved. Experiments on shale gas seepage under different water saturations show that under the condition of fluid–solid coupling, the higher the water saturation is, the better the propagation and seepage capacity of micro-fractures in shale under the effect of pressure. To sum up, the existence of water is beneficial to fracturing stimulation of shale gas reservoirs and helps to achieve the goal of production improvement. Keywords: Shale gas, Core, Fluid–solid coupling, Water, Compression strength, Permeability, Seepage characteristic, Sichuan Basin

  17. A seepage meter designed for use in flowing water

    Science.gov (United States)

    Rosenberry, D.O.

    2008-01-01

    Seepage meters provide one of the most direct means to measure exchange of water across the sediment-water interface, but they generally have been unsuitable for use in fluvial settings. Although the seepage bag can be placed inside a rigid container to minimize velocity head concerns, the seepage cylinder installed in the sediment bed projects into and disrupts the flow field, altering both the local-scale fluid exchange as well as measurement of that exchange. A low-profile seepage meter designed for use in moving water was tested in a seepage meter flux tank where both current velocity and seepage velocity could be controlled. The conical seepage cylinder protrudes only slightly above the sediment bed and is connected via tubing to a seepage bag or flowmeter positioned inside a rigid shelter that is located nearby where current velocity is much slower. Laboratory and field tests indicate that the net effect of the small protrusion of the seepage cylinder into the surface water flow field is inconsequentially small for surface water currents up to 65 cm s-1. Current velocity affects the variability of seepage measurements; seepage standard deviation increased from ???2 to ???6 cm d-1 as current velocity increased from 9 to 65 cm s-1. Substantial bias can result if the shelter is not placed to minimize hydraulic gradient between the bag and the seepage cylinder.

  18. Projected tritium releases from F ampersand H Area Seepage Basins and the Solid Waste Disposal Facilities to Fourmile Branch

    International Nuclear Information System (INIS)

    Looney, B.B.; Haselow, J.S.; Lewis, C.M.; Harris, M.K.; Wyatt, D.E.; Hetrick, C.S.

    1993-01-01

    A large percentage of the radioactivity released to the environment by operations at the Savannah River Site (SRS) is due to tritium. Because of the relative importance of the releases of tritium from SRS facilities through the groundwater to the environment, periodic evaluation and documentation of the facility operational status, proposed corrective actions, and projected changes/reductions in tritium releases are justified. Past, current, and projected tritium releases from the F and H Area Seepage Basins and the Solid Waste Disposal Facilities (SWDF) to Fourmile Branch are described. Each section provides a brief operational history along with the current status and proposed corrective actions. A conceptual model and quantitative estimates of tritium release from the facilities into the groundwater and the environment are developed. Tritium releases from the F and H Area Seepage Basins are declining and will be further reduced by the implementation of a groundwater corrective action required by the Resource Conservation and Recovery Act (RCRA). Tritium releases from the SWDF have been relatively stable over the past 10 years. It is anticipated that SWDF tritium releases to Fourmile Branch will remain approximately at current levels for at least 10--20 years. Specific characterization activities are recommended to allow an improved projection of tritium flux and to assist in developing plans for plume mitigation. SRS and the South Carolina Department of Health and Environmental Control are developing groundwater corrective action plans for the SWDF. Portions of the SWDF are also regulated under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Reduction of tritium flux is one of the factors considered in the development of the RCRA/CERCLA groundwater corrective action. The final section of the document presents the sum of the projected tritium fluxes from these facilities to Fourmile Branch

  19. Abstraction of Drift Seepage

    International Nuclear Information System (INIS)

    J.T. Birkholzer

    2004-01-01

    This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package corrosion or radionuclide transport

  20. H-Area Seepage Basins groundwater monitoring report -- third and fourth quarters 1993. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Butler, C.T.

    1994-03-01

    During the second half of 1993, the groundwater at the H-Area Seepage Basins (HASB) was monitored in compliance with the September 30, 1992, modification of South Carolina Hazardous Waste Permit SC1-890-008-989. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the H-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Beginning first quarter 1993, the HASB`s Groundwater Protection Standard (GWPS), established in Appendix 3D-A of the cited permit, became the standard for comparison. Historically as well as currently, nitrate, nonvolatile beta, and tritium have been among the primary constituents to exceed standards. Other radionuclides and hazardous constitutents also exceeded the GWPS in the groundwater at the HASB (notably aluminum, iodine-129, strontium-90, technetium-99, and zinc) during the second half of 1993. Elevated constituents were found primarily in Aquifer Zone 2B{sub 2} and in the upper portion of Aquifer Zone 2B{sub 1}. However, constituents exceeding standards also occurred in several wells screened in the lower portion of Aquifer Zone 2B{sub 1} and Aquifer Unit 2A. Isoconcentration/isoactivity maps include in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units during the second half of 1993. Water-level maps indicate that the groundwater flow rates and directions at the HASB have remained relatively constant since the basins ceased to be active in 1988.

  1. Superfund record of decision (EPA Region 4): Savannah River Site (USDOE) D-Area Oil Seepage Basin (631-G), Aiken, SC, August 14, 1998

    International Nuclear Information System (INIS)

    1999-03-01

    The D-Area Oil Seepage Basin (D-Area OSB) Operable Unit (OU) is listed as a Resource Conservation and Recovery Act (RCRA) 3004(u) Solid Waste Management Unit/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) unit in Appendix C of the Federal Facility Agreement (FFA) for the Savannah River Site (SRS). No Action is the selected remedy for shallow soil, surface water and sediment, because no constituents of concern (COCs) were identified for them in the RCRA Facility Investigation/Remedial Investigation/Baseline Risk Assessment (RFI/RI/BRA). The selected remedy for D-Area OSB groundwater is Alternative GW-2: Natural Attenuation/Groundwater Mixing Zone (GWMZ) with Institutional Controls

  2. Final technology report for D-Area oil seepage basin bioventing optimization test, environmental restoration support

    International Nuclear Information System (INIS)

    Radway, J.C.; Lombard, K.H.; Hazen, T.C.

    1997-01-01

    One method proposed for the cleanup of the D-Area Oil Seepage Basin was in situ bioremediation (bioventing), involving the introduction of air and gaseous nutrients to stimulate contaminant degradation by naturally occurring microorganisms. To test the feasibility of this approach, a bioventing system was installed at the site for use in optimization testing by the Environmental Biotechnology Section of the Savannah River Technology Center. During the interim action, two horizontal wells for a bioventing remediation system were installed eight feet below average basin grade. Nine piezometers were also installed. In September of 1996, a generator, regenerative blower, gas cylinder station, and associated piping and nutrient injection equipment were installed at the site and testing was begun. After baseline characterization of microbial activity and contaminant degradation at the site was completed, four injection campaigns were carried out. These consisted of (1) air alone, (2) air plus triethylphosphate (TEP), (3) air plus nitrous oxide, and (4) air plus methane. This report describes results of these tests, together with conclusions and recommendations for further remediation of the site. Natural biodegradation rates are high. Oxygen, carbon dioxide, and methane levels in soil gas indicate substantial levels of baseline microbial activity. Oxygen is used by indigenous microbes for biodegradation of organics via respiration and hence is depleted in the soil gas and water from areas with high contamination. Carbon dioxide is elevated in contaminated areas. High concentrations of methane, which is produced by microbes via fermentation once the oxygen has been depleted, are found at the most contaminated areas of this site. Groundwater measurements also indicated that substantial levels of natural contaminant biodegradation occurred prior to air injection

  3. Gas seepage from Tokamachi mud volcanoes, onshore Niigata Basin (Japan): Origin, post-genetic alterations and CH{sub 4}-CO{sub 2} fluxes

    Energy Technology Data Exchange (ETDEWEB)

    Etiope, G., E-mail: etiope@ingv.it [Istituto Nazionale di Geofisica e Vulcanologia, via V. Murata 605, 00143 Roma (Italy); Nakada, R. [Dept. of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University (Japan); Tanaka, K. [Graduate School of Science and Engineering, Yamaguchi University (Japan); Yoshida, N. [Dept. of Environmental Chemistry and Engineering, Tokyo Institute of Technology (Japan)

    2011-03-15

    Research highlights: {yields} Tokamachi gas shows signals of subsurface hydrocarbon biodegradation. {yields} Hydrocarbon molecular fractionation depends on gas flux. {yields} Substantial gas emission from mud volcanoes is from invisible diffuse seepage. {yields} Global mud volcano methane emission is likely higher than 10 Mt a{sup -1}. - Abstract: Methane and CO{sub 2} emissions from the two most active mud volcanoes in central Japan, Murono and Kamou (Tokamachi City, Niigata Basin), were measured in from both craters or vents (macro-seepage) and invisible exhalation from the soil (mini- and microseepage). Molecular and isotopic compositions of the released gases were also determined. Gas is thermogenic ({delta}{sup 13}C{sub CH4} from -32.9 per mille to -36.2 per mille), likely associated with oil, and enrichments of {sup 13}C in CO{sub 2} ({delta}{sup 13}C{sub CO2} up to +28.3 per mille) and propane ({delta}{sup 13}C{sub C3H8} up to -8.6 per mille) suggest subsurface petroleum biodegradation. Gas source and post-genetic alteration processes did not change from 2004 to 2010. Methane flux ranged within the orders of magnitude of 10{sup 1}-10{sup 4} g m{sup -2} d{sup -1} in macro-seeps, and up to 446 g m{sup -2} d{sup -1} from diffuse seepage. Positive CH{sub 4} fluxes from dry soil were widespread throughout the investigated areas. Total CH{sub 4} emission from Murono and Kamou were estimated to be at least 20 and 3.7 ton a{sup -1}, respectively, of which more than half was from invisible seepage surrounding the mud volcano vents. At the macro-seeps, CO{sub 2} fluxes were directly proportional to CH{sub 4} fluxes, and the volumetric ratios between CH{sub 4} flux and CO{sub 2} flux were similar to the compositional CH{sub 4}/CO{sub 2} volume ratio. Macro-seep flux data, in addition to those of other 13 mud volcanoes, supported the hypothesis that molecular fractionation (increase of the 'Bernard ratio' C{sub 1}/(C{sub 2} + C{sub 3})) is inversely

  4. SEEPAGE/INVERT INTERACTIONS

    International Nuclear Information System (INIS)

    P.S. Domski

    2000-01-01

    As directed by a written development plan (CRWMS M andO 1999a), a conceptual model for water entering the drift and reacting with the invert materials is to be developed. The purpose of this conceptual model is to assist Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift, thus allowing PAO to provide a more detailed and complete in-drift geochemical model abstraction, and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE), Revision 2 (NRC 1999). This AMR also seeks to: (1) Develop a logical conceptual model for physical/chemical interactions between seepage and the invert materials; (2) screen potential processes and reactions that may occur between seepage and invert to evaluate the potential consequences of the interactions; and (3) outline how seepage/invert processes may be quantified. This document provides the conceptual framework for screening out insignificant processes and for identifying and evaluating those seepage/invert interactions that have the potential to be important to subsequent PAO analyses including the Engineered Barrier System (EBS) physical and chemical model abstraction effort. This model has been developed to serve as a basis for the in-drift geochemical analyses performed by PAO. Additionally, the concepts discussed within this report may also apply to certain near and far-field geochemical processes and may have conceptual application within the unsaturated zone (UZ) and saturated zone (SZ) transport modeling efforts. The seepage/invert interactions will not directly affect any principal factors

  5. Seepage into drifts with mechanical degradation

    International Nuclear Information System (INIS)

    Li, Guomin; Tsang, Chin-Fu

    2002-01-01

    Seepage into drifts in unsaturated tuff is an important issue for the long-term performance of the potential nuclear waste repository at Yucca Mountain, Nevada. Drifts in which waste packages will potentially be emplaced are subject to degradation in the form of rockfall from the drift ceiling induced by stress relief, seismic, or thermal effects. The objective of this study is to calculate seepage rates for various drift-degradation scenarios and for different values of percolation flux for the Topopah Spring middle nonlithophysal (Tptpmn) and the Topopah Spring lower lithophysal (Tptpll) units. Seepage calculations are conducted by (1) defining a heterogeneous permeability model on the drift scale that is consistent with field data, (2) selecting calibrated parameters associated with the Tptpmn and Tptpll units, and (3) simulating seepage on detailed degraded-drift profiles, which were obtained from a separate rock mechanics engineering analysis. The simulation results indicate (1) that the seepage threshold (i.e., the percolation flux at which seepage first occurs) is not significantly changed by drift degradation, and (2) the degradation-induced increase in seepage above the threshold is influenced more by the shape of the cavity created by rockfall than the rockfall volume

  6. 48 CFR 716.406 - Contract clauses.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract clauses. 716.406 Section 716.406 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 716.406 Contract clauses. The...

  7. Seepage Model for PA Including Drift Collapse

    International Nuclear Information System (INIS)

    Li, G.; Tsang, C.

    2000-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the predictions and analysis performed using the Seepage Model for Performance Assessment (PA) and the Disturbed Drift Seepage Submodel for both the Topopah Spring middle nonlithophysal and lower lithophysal lithostratigraphic units at Yucca Mountain. These results will be used by PA to develop the probability distribution of water seepage into waste-emplacement drifts at Yucca Mountain, Nevada, as part of the evaluation of the long term performance of the potential repository. This AMR is in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' (CRWMS M andO 2000 [153447]). This purpose is accomplished by performing numerical simulations with stochastic representations of hydrological properties, using the Seepage Model for PA, and evaluating the effects of an alternative drift geometry representing a partially collapsed drift using the Disturbed Drift Seepage Submodel. Seepage of water into waste-emplacement drifts is considered one of the principal factors having the greatest impact of long-term safety of the repository system (CRWMS M andO 2000 [153225], Table 4-1). This AMR supports the analysis and simulation that are used by PA to develop the probability distribution of water seepage into drift, and is therefore a model of primary (Level 1) importance (AP-3.15Q, ''Managing Technical Product Inputs''). The intended purpose of the Seepage Model for PA is to support: (1) PA; (2) Abstraction of Drift-Scale Seepage; and (3) Unsaturated Zone (UZ) Flow and Transport Process Model Report (PMR). Seepage into drifts is evaluated by applying numerical models with stochastic representations of hydrological properties and performing flow simulations with multiple realizations of the permeability field around the drift. The Seepage Model for PA uses the distribution of permeabilities derived from air injection testing in niches and in the cross drift to

  8. Seepage Model for PA Including Dift Collapse

    Energy Technology Data Exchange (ETDEWEB)

    G. Li; C. Tsang

    2000-12-20

    The purpose of this Analysis/Model Report (AMR) is to document the predictions and analysis performed using the Seepage Model for Performance Assessment (PA) and the Disturbed Drift Seepage Submodel for both the Topopah Spring middle nonlithophysal and lower lithophysal lithostratigraphic units at Yucca Mountain. These results will be used by PA to develop the probability distribution of water seepage into waste-emplacement drifts at Yucca Mountain, Nevada, as part of the evaluation of the long term performance of the potential repository. This AMR is in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' (CRWMS M&O 2000 [153447]). This purpose is accomplished by performing numerical simulations with stochastic representations of hydrological properties, using the Seepage Model for PA, and evaluating the effects of an alternative drift geometry representing a partially collapsed drift using the Disturbed Drift Seepage Submodel. Seepage of water into waste-emplacement drifts is considered one of the principal factors having the greatest impact of long-term safety of the repository system (CRWMS M&O 2000 [153225], Table 4-1). This AMR supports the analysis and simulation that are used by PA to develop the probability distribution of water seepage into drift, and is therefore a model of primary (Level 1) importance (AP-3.15Q, ''Managing Technical Product Inputs''). The intended purpose of the Seepage Model for PA is to support: (1) PA; (2) Abstraction of Drift-Scale Seepage; and (3) Unsaturated Zone (UZ) Flow and Transport Process Model Report (PMR). Seepage into drifts is evaluated by applying numerical models with stochastic representations of hydrological properties and performing flow simulations with multiple realizations of the permeability field around the drift. The Seepage Model for PA uses the distribution of permeabilities derived from air injection testing in

  9. Assessment of tree toxicity near the F- and H-Area seepage basins of the Savannah River Site

    International Nuclear Information System (INIS)

    Loehle, C.; Richardson, C.J.

    1990-12-01

    Areas of tree mortality, originating in 1979, have been documented downslope of the F- and H-Area Seepage Basins. The basins were used as discharge areas for low-level radioactive and nonradioactive waste. Preliminary studies indicated that there are three possible causes of stress: altered hydrology; hazardous chemicals; and nonhazardous chemicals. It was originally hypothesized that the most likely hydrological stressors to Nyssa sylvatica var. biflora were flooding where water levels cover the lenticels for more than 26 percent of the growing season, resulting in low oxygen availability, and toxins produced under anaerobic conditions. In fact, trees began to show stress only flowing a drought year (1977) rather than a wet year. Dry conditions could exacerbate stress by concentrating contaminants, particularly salt. Study of the soil and water chemical parameters in the impacted sites indicated that salt concentrations in the affected areas have produced abnormally high exchangeable sodium percentages. Furthermore, significantly elevated concentrations of heavy metals were found in each impacted site, although no one metal was consistently elevated. Evaluation of the concentrations of various chemicals toxic to Nyssa sylvatica var. biflora revealed that aluminum was probably the most toxic in the F-Area. Manganese, cadmium, and zinc had concentrations great enough to be considered possible causes of tree mortality in the F-Area. Aluminum was the most likely cause of mortality in the H-Area. Controlled experiments testing metal and salt concentration effects on Nyssa sylvatica would be needed to specifically assign cause and effect mortality relationships

  10. Assessment of tree toxicity near the F- and H-Area seepage basins of the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. (ed.) (Westinghouse Savannah River Co., Aiken, SC (USA)); Richardson, C.J. (ed.); Greenwood, K.P.; Hane, M.E.; Lander, A.J. (Duke Univ., Durham, NC (USA))

    1990-12-01

    Areas of tree mortality, originating in 1979, have been documented downslope of the F- and H-Area Seepage Basins. The basins were used as discharge areas for low-level radioactive and nonradioactive waste. Preliminary studies indicated that there are three possible causes of stress: altered hydrology; hazardous chemicals; and nonhazardous chemicals. It was originally hypothesized that the most likely hydrological stressors to Nyssa sylvatica var. biflora were flooding where water levels cover the lenticels for more than 26 percent of the growing season, resulting in low oxygen availability, and toxins produced under anaerobic conditions. In fact, trees began to show stress only flowing a drought year (1977) rather than a wet year. Dry conditions could exacerbate stress by concentrating contaminants, particularly salt. Study of the soil and water chemical parameters in the impacted sites indicated that salt concentrations in the affected areas have produced abnormally high exchangeable sodium percentages. Furthermore, significantly elevated concentrations of heavy metals were found in each impacted site, although no one metal was consistently elevated. Evaluation of the concentrations of various chemicals toxic to Nyssa sylvatica var. biflora revealed that aluminum was probably the most toxic in the F-Area. Manganese, cadmium, and zinc had concentrations great enough to be considered possible causes of tree mortality in the F-Area. Aluminum was the most likely cause of mortality in the H-Area. Controlled experiments testing metal and salt concentration effects on Nyssa sylvatica would be needed to specifically assign cause and effect mortality relationships.

  11. 30 CFR 716.5 - Anthracite coal mines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Anthracite coal mines. 716.5 Section 716.5... PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.5 Anthracite coal mines. (a) Permittees of anthracite surface coal mining and reclamation operations in those States where the mines are regulated by...

  12. Geophysical and hydrologic studies of lake seepage variability

    Science.gov (United States)

    Toran, Laura; Nyquist, Jonathan E.; Rosenberry, Donald O.; Gagliano, Michael P.; Mitchell, Natasha; Mikochik, James

    2014-01-01

    Variations in lake seepage were studied along a 130 m shoreline of Mirror Lake NH. Seepage was downward from the lake to groundwater; rates measured from 28 seepage meters varied from 0 to −282 cm/d. Causes of this variation were investigated using electrical resistivity surveys and lakebed sediment characterization. Two-dimensional (2D) resistivity surveys showed a transition in lakebed sediments from outwash to till that correlated with high- and low-seepage zones, respectively. However, the 2D survey was not able to predict smaller scale variations within these facies. In the outwash, fast seepage was associated with permeability variations in a thin (2 cm) layer of sediments at the top of the lakebed. In the till, where seepage was slower than that in the outwash, a three-dimensional resistivity survey mapped a point of high seepage associated with heterogeneity (lower resistivity and likely higher permeability). Points of focused flow across the sediment–water interface are difficult to detect and can transmit a large percentage of total exchange. Using a series of electrical resistivity geophysical methods in combination with hydrologic data to locate heterogeneities that affect seepage rates can help guide seepage meter placement. Improving our understanding of the causes and types of heterogeneity in lake seepage will provide better data for lake budgets and prediction of mass transfer of solutes or contaminants between lakes and groundwater.

  13. 32 CFR 716.5 - Delegation of authority.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Delegation of authority. 716.5 Section 716.5 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL DEATH GRATUITY Provisions Applicable to the Navy and the Marine Corps § 716.5 Delegation of authority. (a) Pursuant to the...

  14. POST-PROCESSING ANALYSIS FOR THC SEEPAGE

    International Nuclear Information System (INIS)

    SUN, Y.

    2004-01-01

    This report describes the selection of water compositions for the total system performance assessment (TSPA) model of results from the thermal-hydrological-chemical (THC) seepage model documented in ''Drift-Scale THC Seepage Model'' (BSC 2004 [DIRS 169856]). The selection has been conducted in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2004 [DIRS 171334]). This technical work plan (TWP) was prepared in accordance with AP-2.27Q, ''Planning for Science Activities''. Section 1.2.3 of the TWP describes planning information pertaining to the technical scope, content, and management of this report. The post-processing analysis for THC seepage (THC-PPA) documented in this report provides a methodology for evaluating the near-field compositions of water and gas around a typical waste emplacement drift as these relate to the chemistry of seepage, if any, into the drift. The THC-PPA inherits the conceptual basis of the THC seepage model, but is an independently developed process. The relationship between the post-processing analysis and other closely related models, together with their main functions in providing seepage chemistry information for the Total System Performance Assessment for the License Application (TSPA-LA), are illustrated in Figure 1-1. The THC-PPA provides a data selection concept and direct input to the physical and chemical environment (P and CE) report that supports the TSPA model. The purpose of the THC-PPA is further discussed in Section 1.2. The data selection methodology of the post-processing analysis (Section 6.2.1) was initially applied to results of the THC seepage model as presented in ''Drift-Scale THC Seepage Model'' (BSC 2004 [DIRS 169856]). Other outputs from the THC seepage model (DTN: LB0302DSCPTHCS.002 [DIRS 161976]) used in the P and CE (BSC 2004 [DIRS 169860

  15. Drift-Scale THC Seepage Model

    International Nuclear Information System (INIS)

    C.R. Bryan

    2005-01-01

    The purpose of this report (REV04) is to document the thermal-hydrologic-chemical (THC) seepage model, which simulates the composition of waters that could potentially seep into emplacement drifts, and the composition of the gas phase. The THC seepage model is processed and abstracted for use in the total system performance assessment (TSPA) for the license application (LA). This report has been developed in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2005 [DIRS 172761]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this report. The plan for validation of the models documented in this report is given in Section 2.2.2, ''Model Validation for the DS THC Seepage Model,'' of the TWP. The TWP (Section 3.2.2) identifies Acceptance Criteria 1 to 4 for ''Quantity and Chemistry of Water Contacting Engineered Barriers and Waste Forms'' (NRC 2003 [DIRS 163274]) as being applicable to this report; however, in variance to the TWP, Acceptance Criterion 5 has also been determined to be applicable, and is addressed, along with the other Acceptance Criteria, in Section 4.2 of this report. Also, three FEPS not listed in the TWP (2.2.10.01.0A, 2.2.10.06.0A, and 2.2.11.02.0A) are partially addressed in this report, and have been added to the list of excluded FEPS in Table 6.1-2. This report has been developed in accordance with LP-SIII.10Q-BSC, ''Models''. This report documents the THC seepage model and a derivative used for validation, the Drift Scale Test (DST) THC submodel. The THC seepage model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC submodel uses a drift

  16. Seepage into PEP tunnel

    International Nuclear Information System (INIS)

    Weidner, H.

    1990-01-01

    The current rate of seepage into the PEP tunnel in the vicinity of IR-10 is very low compared to previous years. Adequate means of handling this low flow are in place. It is not clear whether the reduction in the flow is temporary, perhaps due to three consecutive dry years, or permanent due to drainage of a perched water table. During PEP construction a large amount of effort was expended in attempts to seal the tunnel, with no immediate effect. The efforts to ''manage'' the water flow are deemed to be successful. By covering equipment to protect it from dripping water and channeling seepage into the drainage gutters, the seepage has been reduced to a tolerable nuisance. There is no sure, safe procedure for sealing a leaky shotcreted tunnel

  17. Drift-Scale THC Seepage Model

    Energy Technology Data Exchange (ETDEWEB)

    C.R. Bryan

    2005-02-17

    The purpose of this report (REV04) is to document the thermal-hydrologic-chemical (THC) seepage model, which simulates the composition of waters that could potentially seep into emplacement drifts, and the composition of the gas phase. The THC seepage model is processed and abstracted for use in the total system performance assessment (TSPA) for the license application (LA). This report has been developed in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2005 [DIRS 172761]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this report. The plan for validation of the models documented in this report is given in Section 2.2.2, ''Model Validation for the DS THC Seepage Model,'' of the TWP. The TWP (Section 3.2.2) identifies Acceptance Criteria 1 to 4 for ''Quantity and Chemistry of Water Contacting Engineered Barriers and Waste Forms'' (NRC 2003 [DIRS 163274]) as being applicable to this report; however, in variance to the TWP, Acceptance Criterion 5 has also been determined to be applicable, and is addressed, along with the other Acceptance Criteria, in Section 4.2 of this report. Also, three FEPS not listed in the TWP (2.2.10.01.0A, 2.2.10.06.0A, and 2.2.11.02.0A) are partially addressed in this report, and have been added to the list of excluded FEPS in Table 6.1-2. This report has been developed in accordance with LP-SIII.10Q-BSC, ''Models''. This report documents the THC seepage model and a derivative used for validation, the Drift Scale Test (DST) THC submodel. The THC seepage model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral

  18. 7 CFR 58.716 - Nonfat dry milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Nonfat dry milk. 58.716 Section 58.716 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.716 Nonfat dry milk. Nonfat dry milk used in cheese products should meet the requirements...

  19. ABSTRACTION OF DRIFT SEEPAGE

    International Nuclear Information System (INIS)

    Wilson, Michael L.

    2001-01-01

    Drift seepage refers to flow of liquid water into repository emplacement drifts, where it can potentially contribute to degradation of the engineered systems and release and transport of radionuclides within the drifts. Because of these important effects, seepage into emplacement drifts is listed as a ''principal factor for the postclosure safety case'' in the screening criteria for grading of data in Attachment 1 of AP-3.15Q, Rev. 2, ''Managing Technical Product Inputs''. Abstraction refers to distillation of the essential components of a process model into a form suitable for use in total-system performance assessment (TSPA). Thus, the purpose of this analysis/model is to put the information generated by the seepage process modeling in a form appropriate for use in the TSPA for the Site Recommendation. This report also supports the Unsaturated-Zone Flow and Transport Process Model Report. The scope of the work is discussed below. This analysis/model is governed by the ''Technical Work Plan for Unsaturated Zone Flow and Transport Process Model Report'' (CRWMS MandO 2000a). Details of this activity are in Addendum A of the technical work plan. The original Work Direction and Planning Document is included as Attachment 7 of Addendum A. Note that the Work Direction and Planning Document contains tasks identified for both Performance Assessment Operations (PAO) and Natural Environment Program Operations (NEPO). Only the PAO tasks are documented here. The planning for the NEPO activities is now in Addendum D of the same technical work plan and the work is documented in a separate report (CRWMS MandO 2000b). The Project has been reorganized since the document was written. The responsible organizations in the new structure are the Performance Assessment Department and the Unsaturated Zone Department, respectively. The work plan for the seepage abstraction calls for determining an appropriate abstraction methodology, determining uncertainties in seepage, and providing

  20. ANL-W 779 pond seepage test

    International Nuclear Information System (INIS)

    Braun, D.R.

    1992-11-01

    The ANL-W 779 sanitary wastewater treatment ponds are located on the Idaho National Engineering Laboratory (INEL), north of the Argonne National Laboratory -- West (ANL-W) site A seepage test was performed for two Argonne National Laboratory -- West (ANL-W) sanitary wastewater treatment ponds, Facility 779. Seepage rates were measured to determine if the ponds are a wastewater land application facility. The common industry standard for wastewater land application facilities is a field-measured seepage rate of one quarter inch per day or greater

  1. Investigation on shallow groundwater in a small basin using natural radioisotopes

    International Nuclear Information System (INIS)

    Hamada, Hiromasa; Komae, Takami

    1996-01-01

    The authors conducted an investigation on shallow groundwater using natural radioisotopes as indicators in the small basin of the Hinuma River, Kasama City, Ibaraki Prefecture, Japan. 3 H concentrations in the groundwater showed that it originated from precipitation in the 1960's. Since 222 Rn concentrations decreased as groundwater flowed downstream, they were influenced by infiltration of surface water. Especially, during the irrigation period, the decrease of 222 Rn concentrations was remarkable in the lowland. From the distribution of 222 Rn concentrations in surface water, the sections where groundwater seeped into a river were found, and a quantitative analysis of groundwater seepage in the two sections was conducted on the basis of 222 Rn concentrations in groundwater and in surface water. The ratios of groundwater seepage to the flow at the upstream station for the two sections were about 5% and 10%, respectively. The water movement within the basin, i.e., the actual manner in which surface water infiltrated underground and groundwater seeped into a river, was clarified by analyzing the variations of natural radioisotope concentrations in water and the water balance of the basin. (author)

  2. An evaluation of seepage gains and losses in Indian Creek Reservoir, Ada County, Idaho, April 2010–November 2011

    Science.gov (United States)

    Williams, Marshall L.; Etheridge, Alexandra B.

    2013-01-01

    of flow. The reservoir tended to gain water from seepage of groundwater in the early spring months (March–May), while seepage losses to groundwater from the reservoir occurred in the drier months (June–October). Net monthly seepage rates, as computed by the water-budget method, varied greatly. Reservoir gains from seepage ranged from 0.2 to 59.4 acre-feet per month, while reservoir losses to seepage ranged from 1.6 and 26.8 acre-feet per month. An analysis of seepage meter estimates and segmented-Darcy estimates qualitatively supports the seasonal patterns in seepage provided by the water-budget calculations, except that they tended to be much smaller in magnitude. This suggests that actual seepage might be smaller than those estimates made by the water-budget method. Although the results of all three methods indicate that there is some water loss from the reservoir to groundwater, the seepage losses may be due to rewetting of unsaturated near-shore soils, possible replenishment of a perched aquifer, or both, rather than through percolation to the local aquifer that lies 130 feet below the reservoir. A lithologic log from an adjacent well indicates the existence of a clay lithology that is well correlated to the original reservoir’s base elevation. If the clay lithologic unit extends beneath the reservoir basin underlying the fine-grain reservoir bed sediments, the clay layer should act as an effective barrier to reservoir seepage to the local aquifer, which would explain the low seepage loss estimates calculated in this study.

  3. The taming of brackish seepage

    NARCIS (Netherlands)

    Smits, F.J.C.; Olsthoorn, T.; Smulders, L.; van Wielink, I.

    2016-01-01

    In the area that is managed by the waterboard Amstel, Gooi and Vecht, some deep polders are located. Most of them attract large amounts of brackish seepage. This seepage not only contains salt, but also nutriënts.
    Without hydrological intervention, the waterquality in the area would suffer

  4. Numerical Analysis on Seepage in the deep overburden CFRD

    Science.gov (United States)

    Zeyu, GUO; Junrui, CHAI; Yuan, QIN

    2017-12-01

    There are many problems in the construction of hydraulic structures on deep overburden because of its complex foundation structure and poor geological condition. Seepage failure is one of the main problems. The Combination of the seepage control system of the face rockfill dam and the deep overburden can effectively control the seepage of construction of the concrete face rockfill dam on the deep overburden. Widely used anti-seepage measures are horizontal blanket, waterproof wall, curtain grouting and so on, but the method, technique and its effect of seepage control still have many problems thus need further study. Due to the above considerations, Three-dimensional seepage field numerical analysis based on practical engineering case is conducted to study the seepage prevention effect under different seepage prevention methods, which is of great significance to the development of dam technology and the development of hydropower resources in China.

  5. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    Science.gov (United States)

    Dobson, Patrick F.; Ghezzehei, Teamrat A.; Cook, Paul J.; Rodríguez-Pineda, J. Alfredo; Villalba, Lourdes; de La Garza, Rodrigo

    2012-02-01

    A study of seepage occurring in an adit at the Nopal I uranium mine in Chihuahua, Mexico, was conducted as part of an integrated natural analogue study to evaluate the effects of infiltration and seepage on the mobilization and transport of radionuclides. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage. Field observations recorded between April 2005 and December 2006 indicate that seepage is highly heterogeneous with respect to time, location, and quantity. Seepage, precipitation, and fracture data were used to test two hypotheses: (1) that fast flow seepage is triggered by large precipitation events, and (2) that an increased abundance of fractures and/or fracture intersections leads to higher seepage volumes. A few zones in the back adit recorded elevated seepage volumes immediately following large (>20 mm/day) precipitation events, with transit times of less than 4 h through the 8-m thick rock mass. In most locations, there is a 1-6 month time lag between the onset of the rainy season and seepage, with longer times observed for the front adit. There is a less clear-cut relation between fracture abundance and seepage volume; processes such as evaporation and surface flow along the ceiling may also influence seepage.

  6. Natural Offshore Oil Seepage and Related Tarball Accumulation on the California Coastline - Santa Barbara Channel and the Southern Santa Maria Basin: Source Identification and Inventory

    Science.gov (United States)

    Lorenson, T.D.; Hostettler, Frances D.; Rosenbauer, Robert J.; Peters, Kenneth E.; Dougherty, Jennifer A.; Kvenvolden, Keith A.; Gutmacher, Christina E.; Wong, Florence L.; Normark, William R.

    2009-01-01

    Oil spillage from natural sources is very common in the waters of southern California. Active oil extraction and shipping is occurring concurrently within the region and it is of great interest to resource managers to be able to distinguish between natural seepage and anthropogenic oil spillage. The major goal of this study was to establish the geologic setting, sources, and ultimate dispersal of natural oil seeps in the offshore southern Santa Maria Basin and Santa Barbara Basins. Our surveys focused on likely areas of hydrocarbon seepage that are known to occur between Point Arguello and Ventura, California. Our approach was to 1) document the locations and geochemically fingerprint natural seep oils or tar; 2) geochemically fingerprint coastal tar residues and potential tar sources in this region, both onshore and offshore; 3) establish chemical correlations between offshore active seeps and coastal residues thus linking seep sources to oil residues; 4) measure the rate of natural seepage of individual seeps and attempt to assess regional natural oil and gas seepage rates; and 5) interpret the petroleum system history for the natural seeps. To document the location of sub-sea oil seeps, we first looked into previous studies within and near our survey area. We measured the concentration of methane gas in the water column in areas of reported seepage and found numerous gas plumes and measured high concentrations of methane in the water column. The result of this work showed that the seeps were widely distributed between Point Conception east to the vicinity of Coal Oil Point, and that they by in large occur within the 3-mile limit of California State waters. Subsequent cruises used sidescan and high resolution seismic to map the seafloor, from just south of Point Arguello, east to near Gaviota, California. The results of the methane survey guided the exploration of the area west of Point Conception east to Gaviota using a combination of seismic instruments. The

  7. Transient Seepage for Levee Engineering Analyses

    Science.gov (United States)

    Tracy, F. T.

    2017-12-01

    Historically, steady-state seepage analyses have been a key tool for designing levees by practicing engineers. However, with the advances in computer modeling, transient seepage analysis has become a potentially viable tool. A complication is that the levees usually have partially saturated flow, and this is significantly more complicated in transient flow. This poster illustrates four elements of our research in partially saturated flow relating to the use of transient seepage for levee design: (1) a comparison of results from SEEP2D, SEEP/W, and SLIDE for a generic levee cross section common to the southeastern United States; (2) the results of a sensitivity study of varying saturated hydraulic conductivity, the volumetric water content function (as represented by van Genuchten), and volumetric compressibility; (3) a comparison of when soils do and do not exhibit hysteresis, and (4) a description of proper and improper use of transient seepage in levee design. The variables considered for the sensitivity and hysteresis studies are pore pressure beneath the confining layer at the toe, the flow rate through the levee system, and a levee saturation coefficient varying between 0 and 1. Getting results for SEEP2D, SEEP/W, and SLIDE to match proved more difficult than expected. After some effort, the results matched reasonably well. Differences in results were caused by various factors, including bugs, different finite element meshes, different numerical formulations of the system of nonlinear equations to be solved, and differences in convergence criteria. Varying volumetric compressibility affected the above test variables the most. The levee saturation coefficient was most affected by the use of hysteresis. The improper use of pore pressures from a transient finite element seepage solution imported into a slope stability computation was found to be the most grievous mistake in using transient seepage in the design of levees.

  8. Solution of AntiSeepage for Mengxi River Based on Numerical Simulation of Unsaturated Seepage

    Science.gov (United States)

    Ji, Youjun; Zhang, Linzhi; Yue, Jiannan

    2014-01-01

    Lessening the leakage of surface water can reduce the waste of water resources and ground water pollution. To solve the problem that Mengxi River could not store water enduringly, geology investigation, theoretical analysis, experiment research, and numerical simulation analysis were carried out. Firstly, the seepage mathematical model was established based on unsaturated seepage theory; secondly, the experimental equipment for testing hydraulic conductivity of unsaturated soil was developed to obtain the curve of two-phase flow. The numerical simulation of leakage in natural conditions proves the previous inference and leakage mechanism of river. At last, the seepage control capacities of different impervious materials were compared by numerical simulations. According to the engineering actuality, the impervious material was selected. The impervious measure in this paper has been proved to be effectible by hydrogeological research today. PMID:24707199

  9. SEEPAGE MODEL FOR PA INCLUDING DRIFT COLLAPSE

    International Nuclear Information System (INIS)

    C. Tsang

    2004-01-01

    The purpose of this report is to document the predictions and analyses performed using the seepage model for performance assessment (SMPA) for both the Topopah Spring middle nonlithophysal (Tptpmn) and lower lithophysal (Tptpll) lithostratigraphic units at Yucca Mountain, Nevada. Look-up tables of seepage flow rates into a drift (and their uncertainty) are generated by performing numerical simulations with the seepage model for many combinations of the three most important seepage-relevant parameters: the fracture permeability, the capillary-strength parameter 1/a, and the percolation flux. The percolation flux values chosen take into account flow focusing effects, which are evaluated based on a flow-focusing model. Moreover, multiple realizations of the underlying stochastic permeability field are conducted. Selected sensitivity studies are performed, including the effects of an alternative drift geometry representing a partially collapsed drift from an independent drift-degradation analysis (BSC 2004 [DIRS 166107]). The intended purpose of the seepage model is to provide results of drift-scale seepage rates under a series of parameters and scenarios in support of the Total System Performance Assessment for License Application (TSPA-LA). The SMPA is intended for the evaluation of drift-scale seepage rates under the full range of parameter values for three parameters found to be key (fracture permeability, the van Genuchten 1/a parameter, and percolation flux) and drift degradation shape scenarios in support of the TSPA-LA during the period of compliance for postclosure performance [Technical Work Plan for: Performance Assessment Unsaturated Zone (BSC 2002 [DIRS 160819], Section I-4-2-1)]. The flow-focusing model in the Topopah Spring welded (TSw) unit is intended to provide an estimate of flow focusing factors (FFFs) that (1) bridge the gap between the mountain-scale and drift-scale models, and (2) account for variability in local percolation flux due to

  10. Seepage/Cement Interactions

    International Nuclear Information System (INIS)

    Carpenter, D.

    2000-01-01

    The Development Plan (CRWMS M andO 1999a) pertaining to this task defines the work scopes and objectives for development of various submodels for the Physical and Chemical Environment Abstraction Model for TSPA-LA. The Development Plan (CRWMS M andO 1999a) for this specific task establishes that an evaluation be performed of the chemical reactions between seepage that has entered the drift and concrete which might be used in the repository emplacement drifts. The Development Plan (CRWMS M andO 1999a) then states that the potential effects of these water/grout reactions on chemical conditions in the drift be assessed factoring in the influence of carbonation and the relatively small amount of grout. This task is also directed at: (1) developing a conceptualization of important cement/seepage interactions and potential impacts on EBS performance, (2) performing a screening analysis to assess the importance of cement/seepage interactions. As the work progresses and evolves on other studies, specifically the Engineered Barrier System: Physical and Chemical Environment (P andCE) Model (in progress), many of the issues associated with items 1 and 2, above, will be assessed. Such issues include: (1) Describing the mineralogy of the specified cementitious grout and its evolution over time. (2) Describing the composition of the water before contacting the grout. (3) Developing reasonable upper-bound estimates for the composition of water contacting grout, emphasizing pH and concentrations for anions such as sulfate. (4) Evaluating the equilibration of cement-influenced water with backfill and gas-phase CO 2 . (5) Developing reasonable-bound estimates for flow rate of affected water into the drift. The concept of estimating an ''upper-bound'' range for reaction between the grout and the seepage, particularly in terms of pH is based on equilibrium being established between the seepage and the grout. For example, this analysis can be based on equilibrium being established as

  11. Solution of AntiSeepage for Mengxi River Based on Numerical Simulation of Unsaturated Seepage

    Directory of Open Access Journals (Sweden)

    Youjun Ji

    2014-01-01

    Full Text Available Lessening the leakage of surface water can reduce the waste of water resources and ground water pollution. To solve the problem that Mengxi River could not store water enduringly, geology investigation, theoretical analysis, experiment research, and numerical simulation analysis were carried out. Firstly, the seepage mathematical model was established based on unsaturated seepage theory; secondly, the experimental equipment for testing hydraulic conductivity of unsaturated soil was developed to obtain the curve of two-phase flow. The numerical simulation of leakage in natural conditions proves the previous inference and leakage mechanism of river. At last, the seepage control capacities of different impervious materials were compared by numerical simulations. According to the engineering actuality, the impervious material was selected. The impervious measure in this paper has been proved to be effectible by hydrogeological research today.

  12. Effect of pore structure on the seepage characteristics of tight sandstone reservoirs: A case study of Upper Jurassic Penglaizhen Fm reservoirs in the western Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Liqiang Sima

    2017-01-01

    Full Text Available Tight sandstone reservoirs are characterized by complex pore structures and strong heterogeneity, and their seepage characteristics are much different from those of conventional sandstone reservoirs. In this paper, the tight sandstone reservoirs of Upper Jurassic Penglaizhen Fm in western Sichuan Basin were analyzed in terms of their pore structures by using the data about physical property, mercury injection and nuclear magnetic resonance (NMR tests. Then, the seepage characteristics and the gas–water two-phase migration mechanisms and distribution of tight sandstone reservoirs with different types of pore structures in the process of hydrocarbon accumulation and development were simulated by combining the relative permeability experiment with the visual microscopic displacement model. It is shown that crotch-like viscous fingering occurs in the process of gas front advancing in reservoirs with different pore structures. The better the pore structure is, the lower the irreducible water saturation is; the higher the gas-phase relative permeability of irreducible water is, the more easily the gas reservoir can be developed. At the late stage of development, the residual gas is sealed in reservoirs in the forms of bypass, cutoff and dead end. In various reservoirs, the interference between gas and water is stronger, so gas and water tends to be produced simultaneously. The sealed gas may reduce the production rate of gas wells significantly, and the existence of water phase may reduce the gas permeability greatly; consequently, the water-bearing low-permeability tight sandstone gas reservoirs reveal serious water production, highly-difficult development and low-recovery percentage at the late stage, which have adverse impacts on the effective production and development of gas wells.

  13. Detection Model for Seepage Behavior of Earth Dams Based on Data Mining

    Directory of Open Access Journals (Sweden)

    Zhenxiang Jiang

    2018-01-01

    Full Text Available Seepage behavior detecting is an important tool for ensuring the safety of earth dams. However, traditional seepage behavior detection methods have used insufficient monitoring data and have mainly focused on single-point measures and local seepage behavior. The seepage behavior of dams is not quantitatively detected based on the monitoring data with multiple measuring points. Therefore, this study uses data mining techniques to analyze the monitoring data and overcome the above-mentioned shortcomings. The massive seepage monitoring data with multiple points are used as the research object. The key information on seepage behavior is extracted using principal component analysis. The correlation between seepage behavior and upstream water level is described as mutual information. A detection model for overall seepage behavior is established. Result shows that the model can completely extract the seepage monitoring data with multiple points and quantitatively detect the overall seepage behavior of earth dams. The proposed method can provide a new and reasonable means of quantitatively detecting the overall seepage behavior of earth dams.

  14. Quantification of Seepage in Groundwater Dependent Wetlands

    DEFF Research Database (Denmark)

    Johansen, Ole; Beven, Keith; Jensen, Jacob Birk

    2018-01-01

    Restoration and management of groundwater dependent wetlands require tools for quantifying the groundwater seepage process. A method for determining point estimates of the groundwater seepage based on water level observations is tested. The study is based on field data from a Danish rich fen...

  15. 40 CFR 716.25 - Adequate file search.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the required...

  16. H-Area Seepage Basins: Environmental information document

    International Nuclear Information System (INIS)

    Killian, T.H.; Kolb, N.L.; Corbo, P.

    1986-12-01

    The basins contain liquid low-level radioactivity and chemicals from the H-Area separations facility. Wells monitor the water table in the vicinity of the basins and also underlying aquifers to detect any vertical contaminant migration. A statistical analysis of monitoring data from this site indicates elevated levels of chloride, fluoride, manganese, mercury, nitrate, sodium, and total radium in the groundwater. The predominant pathways for human exposure to contaminants are surface, subsurface, and atmospheric transport. Modeling calculations were performed to determine the risks to humans via these pathways for the postulated closure options. Modeling calculations were also performed to determine ecological impacts. The environmental impact evaluation indicates that the relative human health risks for all closure options are low. Tritium, the dominant radionuclide, reached a maximum risk in Year -29 (from 1985) of 2.7E-04 HE/yr. Results of the atmospheric pathway modeling indicate that risks associated with the no action option are 2 or more orders of magnitude greater than the waste removal closure option for both radionuclides and chemicals. Ecological analysis indicates that the choice of closure option has no effect on the maximum surface water quality impacts. Implementation of no waste removal or waste removal closure options would not appreciably accelerate a decline in groundwater outcrop concentrations. 49 refs., 41 figs., 94 tabs

  17. Delineating a road-salt plume in lakebed sediments using electrical resistivity, piezometers, and seepage meters at Mirror Lake, New Hampshire, U.S.A

    Science.gov (United States)

    Toran, Laura; Johnson, Melanie; Nyquist, Jonathan E.; Rosenberry, Donald O.

    2010-01-01

    Electrical-resistivity surveys, seepage meter measurements, and drive-point piezometers have been used to characterize chloride-enriched groundwater in lakebed sediments of Mirror Lake, New Hampshire, U.S.A. A combination of bottom-cable and floating-cable electrical-resistivity surveys identified a conductive zone (ohm-m)">(ohm-m)(ohm-m) overlying resistive bedrock (ohm-m)">(ohm-m)(ohm-m)beneath the lake. Shallow pore-water samples from piezometers in lakebed sediments have chloride concentrations of 200–1800μeq/liter">200–1800μeq/liter200–1800μeq/liter, and lake water has a chloride concentration of 104μeq/liter">104μeq/liter104μeq/liter. The extent of the plume was estimated and mapped using resistivity and water-sample data. The plume (20×35m">20×35m20×35m wide and at least 3m">3m3m thick) extends nearly the full length and width of a small inlet, overlying the top of a basin formed by the bedrock. It would not have been possible to mapthe plume's shape without the resistivity surveys because wells provided only limited coverage. Seepage meters were installed approximately 40m">40m40m from the mouth of a small stream discharging at the head of the inlet in an area where the resistivity data indicated lake sediments are thin. These meters recorded in-seepage of chloride-enriched groundwater at rates similar to those observed closer to shore, which was unexpected because seepage usually declines away from shore. Although the concentration of road salt in the northeast inlet stream is declining, the plume map and seepage data indicate the groundwater contribution of road salt to the lake is not declining. The findings demonstrate the benefit of combining geophysical and hydrologic data to characterize discharge of a plume beneath Mirror Lake. The extent of the plume in groundwater beneath the lake and stream indicate there will likely be a long-term source of chloride to the lake from groundwater.

  18. Modeling Coupled Evaporation and Seepage in Ventilated Cavities

    International Nuclear Information System (INIS)

    Ghezzehei, T.; Trautz, R.; Finsterle, S.; Cook, P.; Ahlers, C.

    2004-01-01

    Cavities excavated in unsaturated geological formations are important to activities such as nuclear waste disposal and mining. Such cavities provide a unique setting for simultaneous occurrence of seepage and evaporation. Previously, inverse numerical modeling of field liquid-release tests and associated seepage into cavities were used to provide seepage-related large-scale formation properties by ignoring the impact of evaporation. The applicability of such models was limited to the narrow range of ventilation conditions under which the models were calibrated. The objective of this study was to alleviate this limitation by incorporating evaporation into the seepage models. We modeled evaporation as an isothermal vapor diffusion process. The semi-physical model accounts for the relative humidity, temperature, and ventilation conditions of the cavities. The evaporation boundary layer thickness (BLT) over which diffusion occurs was estimated by calibration against free-water evaporation data collected inside the experimental cavities. The estimated values of BLT were 5 to 7 mm for the open underground drifts and 20 mm for niches closed off by bulkheads. Compared to previous models that neglected the effect of evaporation, this new approach showed significant improvement in capturing seepage fluctuations into open cavities of low relative humidity. At high relative-humidity values (greater than 85%), the effect of evaporation on seepage was very small

  19. Evolution Procedure of Multiple Rock Cracks under Seepage Pressure

    Directory of Open Access Journals (Sweden)

    Taoying Liu

    2013-01-01

    Full Text Available In practical geotechnical engineering, most of rock masses with multiple cracks exist in water environment. Under such circumstance, these adjacent cracks could interact with each other. Moreover, the seepage pressure, produced by the high water pressure, can change cracks’ status and have an impact on the stress state of fragile rocks. According to the theory of fracture mechanics, this paper discusses the law of crack initiation and the evolution law of stress intensity factor at the tip of a wing crack caused by compression-shear stress and seepage pressure. Subsequently, considering the interaction of the wing cracks and the additional stress caused by rock bridge damage, this paper proposes the intensity factor evolution equation under the combined action of compression-shear stress and seepage pressure. In addition, this paper analyzes the propagation of cracks under different seepage pressure which reveals that the existence of seepage pressure facilitates the wing crack’s growth. The result indicates that the high seepage pressure converts wing crack growth from stable form to unstable form. Meanwhile, based on the criterion and mechanism for crack initiation and propagation, this paper puts forward the mechanical model for different fracture transfixion failure modes of the crag bridge under the combined action of seepage pressure and compression-shear stress. At the last part, this paper, through investigating the flexibility tensor of the rock mass’s initial damage and its damage evolution in terms of jointed rock mass's damage mechanics, deduces the damage evolution equation for the rock mass with multiple cracks under the combined action of compression-shear stress and seepage pressure. The achievement of this investigation provides a reliable theoretical principle for quantitative research of the fractured rock mass failure under seepage pressure.

  20. 20 CFR 71.6 - Notice of injury or death.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Notice of injury or death. 71.6 Section 71.6..., DISABILITY OR DEATH OF CIVILIAN AMERICAN CITIZENS INCURRED WHILE DETAINED BY OR IN HIDING FROM THE IMPERIAL JAPANESE GOVERNMENT GENERAL PROVISIONS § 71.6 Notice of injury or death. Notwithstanding any of the...

  1. Cleveland Dam East Abutment : seepage control project

    Energy Technology Data Exchange (ETDEWEB)

    Huber, F.; Siu, D. [Greater Vancouver Regional District, Burnaby, BC (Canada); Ahlfield, S.; Singh, N. [Klohn Crippen Consultants Ltd., Vancouver, BC (Canada)

    2004-09-01

    North Vancouver's 91 meter high Cleveland Dam was built in the 1950s in a deep bedrock canyon to provide a reservoir for potable water to 18 municipalities. Flow in the concrete gravity dam is controlled by a gated spillway, 2 mid-level outlets and intakes and 2 low-level outlets. This paper describes the seepage control measures that were taken at the time of construction as well as the additional measures that were taken post construction to control piezometric levels, seepage and piping and slope instability in the East Abutment. At the time of construction, a till blanket was used to cover the upstream reservoir slope for 200 meters upstream of the dam. A single line grout curtain was used through the overburden from ground surface to bedrock for a distance of 166 meters from the dam to the East Abutment. Since construction, the safety of the dam has been compromised through changes in piezometric pressure, seepage and soil loss. Klohn Crippen Consultants designed a unique seepage control measure to address the instability risk. The project involved excavating 300,000 cubic meters of soil to form a stable slope and construction bench. A vertical wall was constructed to block seepage. The existing seepage control blanket was also extended by 260 meters. The social, environmental and technical issues that were encountered during the rehabilitation project are also discussed. The blanket extension construction has met design requirements and the abutment materials that are most susceptible to internal erosion have been covered by non-erodible blanket materials such as plastic and roller-compacted concrete (RCC). The project was completed on schedule and within budget and has greatly improved the long-term stability of the dam and public safety. 2 refs., 8 figs.

  2. 30 CFR 716.4 - Special bituminous coal mines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special bituminous coal mines. 716.4 Section... INTERIOR INITIAL PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.4 Special bituminous coal mines. (a) Definition. Special bituminous coal surface mines as used in this section means those bituminous...

  3. 12 CFR 716.15 - Other exceptions to notice and opt out requirements.

    Science.gov (United States)

    2010-01-01

    ... insurance to the consumer. (2) A consumer may revoke consent by subsequently exercising the right to opt out... AFFECTING CREDIT UNIONS PRIVACY OF CONSUMER FINANCIAL INFORMATION Exceptions § 716.15 Other exceptions to... notice to consumers in § 716.4(a)(2), the opt out in §§ 716.7 and 716.10 and service providers and joint...

  4. Investigation of Seepage Meter Measurements in Steady Flow and Wave Conditions.

    Science.gov (United States)

    Russoniello, Christopher J; Michael, Holly A

    2015-01-01

    Water exchange between surface water and groundwater can modulate or generate ecologically important fluxes of solutes across the sediment-water interface. Seepage meters can directly measure fluid flux, but mechanical resistance and surface water dynamics may lead to inaccurate measurements. Tank experiments were conducted to determine effects of mechanical resistance on measurement efficiency and occurrence of directional asymmetry that could lead to erroneous net flux measurements. Seepage meter efficiency was high (average of 93%) and consistent for inflow and outflow under steady flow conditions. Wave effects on seepage meter measurements were investigated in a wave flume. Seepage meter net flux measurements averaged 0.08 cm/h-greater than the expected net-zero flux, but significantly less than theoretical wave-driven unidirectional discharge or recharge. Calculations of unidirectional flux from pressure measurements (Darcy flux) and theory matched well for a ratio of wave length to water depth less than 5, but not when this ratio was greater. Both were higher than seepage meter measurements of unidirectional flux made with one-way valves. Discharge averaged 23% greater than recharge in both seepage meter measurements and Darcy calculations of unidirectional flux. Removal of the collection bag reduced this net discharge. The presence of a seepage meter reduced the amplitude of pressure signals at the bed and resulted in a nearly uniform pressure distribution beneath the seepage meter. These results show that seepage meters may provide accurate measurements of both discharge and recharge under steady flow conditions and illustrate the potential measurement errors associated with dynamic wave environments. © 2014, National Ground Water Association.

  5. 12 CFR 716.11 - Limits on redisclosure and reuse of information.

    Science.gov (United States)

    2010-01-01

    ... CREDIT UNIONS PRIVACY OF CONSUMER FINANCIAL INFORMATION Limits on Disclosures § 716.11 Limits on... nonpublic personal information from a nonaffiliated financial institution under an exception in § 716.14 or 716.15 of this part, your disclosure and use of that information is limited as follows: (i) You may...

  6. The role of optimality in characterizing CO2 seepage from geological carbon sequestration sites

    Energy Technology Data Exchange (ETDEWEB)

    Cortis, Andrea; Oldenburg, Curtis M.; Benson, Sally M.

    2008-09-15

    Storage of large amounts of carbon dioxide (CO{sub 2}) in deep geological formations for greenhouse gas mitigation is gaining momentum and moving from its conceptual and testing stages towards widespread application. In this work we explore various optimization strategies for characterizing surface leakage (seepage) using near-surface measurement approaches such as accumulation chambers and eddy covariance towers. Seepage characterization objectives and limitations need to be defined carefully from the outset especially in light of large natural background variations that can mask seepage. The cost and sensitivity of seepage detection are related to four critical length scales pertaining to the size of the: (1) region that needs to be monitored; (2) footprint of the measurement approach, and (3) main seepage zone; and (4) region in which concentrations or fluxes are influenced by seepage. Seepage characterization objectives may include one or all of the tasks of detecting, locating, and quantifying seepage. Each of these tasks has its own optimal strategy. Detecting and locating seepage in a region in which there is no expected or preferred location for seepage nor existing evidence for seepage requires monitoring on a fixed grid, e.g., using eddy covariance towers. The fixed-grid approaches needed to detect seepage are expected to require large numbers of eddy covariance towers for large-scale geologic CO{sub 2} storage. Once seepage has been detected and roughly located, seepage zones and features can be optimally pinpointed through a dynamic search strategy, e.g., employing accumulation chambers and/or soil-gas sampling. Quantification of seepage rates can be done through measurements on a localized fixed grid once the seepage is pinpointed. Background measurements are essential for seepage detection in natural ecosystems. Artificial neural networks are considered as regression models useful for distinguishing natural system behavior from anomalous behavior

  7. Calculating earth dam seepage using HYDRUS software applications

    Directory of Open Access Journals (Sweden)

    Jakub Nieć

    2017-06-01

    Full Text Available This paper presents simulations of water seepage within and under the embankment dam of Lake Kowalskie reservoir. The aim of the study was to compare seepage calculation results obtained using analytical and numerical methods. In April 1985, after the first filling of the reservoir to normal storage levels, water leaks was observed at the base of the escarpment, on the air side of the dam. In order to control seepage flow, drainage was performed and additional piezometers installed. To explain the causes of increased pressure in the aquifer under the dam in May 1985 a simplified calculation of filtration was performed. Now, on the basis of archived data from the Department of Hydraulic and Sanitary Engineering using 3D HYDRUS STANDARD software, the conditions of seepage under the dam have been recreated and re-calculated. Piezometric pressure was investigated in three variants of drainage, including drainage before and after modernization.

  8. A coupling model for gas diffusion and seepage in SRV section of shale gas reservoirs

    Directory of Open Access Journals (Sweden)

    Shusheng Gao

    2017-03-01

    Full Text Available A prerequisite to effective shale gas development is a complicated fracture network generated by extensive and massive fracturing, which is called SRV (stimulated reservoir volume section. Accurate description of gas flow behaviors in such section is fundamental for productivity evaluation and production performance prediction of shale gas wells. The SRV section is composed of bedrocks with varying sizes and fracture networks, which exhibit different flow behaviors – gas diffusion in bedrocks and gas seepage in fractures. According to the porosity and permeability and the adsorption, diffusion and seepage features of bedrocks and fractures in a shale gas reservoir, the material balance equations were built for bedrocks and fractures respectively and the continuity equations of gas diffusion and seepage in the SRV section were derived. For easy calculation, the post-frac bedrock cube was simplified to be a sphere in line with the principle of volume consistency. Under the assumption of quasi-steady flow behavior at the cross section of the sphere, the gas channeling equation was derived based on the Fick's laws of diffusion and the density function of gas in bedrocks and fractures. The continuity equation was coupled with the channeling equation to effectively characterize the complicated gas flow behavior in the SRV section. The study results show that the gas diffusivity in bedrocks and the volume of bedrocks formed by volume fracturing (or the scale of fracturing jointly determines the productivity and stable production period of a shale gas well. As per the actual calculation for the well field A in the Changning–Weiyuan Block in the Sichuan Basin, the matrix has low gas diffusivity – about 10−5 cm2/s and a large volume with an equivalent sphere radius of 6.2 m, hindering the gas channeling from bedrocks to fractures and thereby reducing the productivity of the shale gas well. It is concluded that larger scale of volume fracturing

  9. Air Compressibility Effect on Bouwer and Rice Seepage Meter.

    Science.gov (United States)

    Peng, Xin; Zhan, Hongbin

    2017-11-01

    Measuring a disconnected streambed seepage flux using a seepage meter can give important streambed information and help understanding groundwater-surface water interaction. In this study, we provide a correction for calculating the seepage flux rate with the consideration of air compressibility inside the manometer of the Bouwer and Rice seepage meter. We notice that the effect of air compressibility in the manometer is considerably larger when more air is included in the manometer. We find that the relative error from neglecting air compressibility can be constrained within 5% if the manometer of the Bouwer and Rice seepage meter is shorter than 0.8 m and the experiment is done in a suction mode in which air is pumped out from the manometer before the start of measurement. For manometers longer than 0.8 m, the relative error will be larger than 5%. It may be over 10% if the manometer height is longer than 1.5 m and the experiment is done in a no-suction mode, in which air is not pumped out from the manometer before the start of measurement. © 2017, National Ground Water Association.

  10. Characterization of UGT716A1 as a Multi-substrate UDP:Flavonoid Glucosyltransferase Gene in Ginkgo biloba

    Directory of Open Access Journals (Sweden)

    Xiaojia Su

    2017-12-01

    Full Text Available Ginkgo biloba L., a “living fossil” and medicinal plant, is a well-known rich source of bioactive flavonoids. The molecular mechanism underlying the biosynthesis of flavonoid glucosides, the predominant flavonoids in G. biloba, remains unclear. To better understand flavonoid glucosylation in G. biloba, we generated a transcriptomic dataset of G. biloba leaf tissue by high-throughput RNA sequencing. We identified 25 putative UDP-glycosyltransferase (UGT unigenes that are potentially involved in the flavonoid glycosylation. Among them, we successfully isolated and expressed eight UGT genes in Escherichia coli, and found that recombinant UGT716A1 protein was active toward broad range of flavonoid/phenylpropanoid substrates. In particular, we discovered the first recombinant UGT protein, UGT716A1 from G. biloba, possessing unique activity toward flavanol gallates that have been extensively documented to have significant bioactivity relating to human health. UGT716A1 expression level paralleled the flavonoid distribution pattern in G. biloba. Ectopic over-expression of UGT716A1 in Arabidopsis thaliana led to increased accumulation of several flavonol glucosides. Identification and comparison of the in vitro enzymatic activity of UGT716A1 homologs revealed a UGT from the primitive land species Physcomitrella patens also showed broader substrate spectrum than those from higher plants A. thaliana, Vitis vinifera, and Medicago truncatula. The characterization of UGT716A1 from G. biloba bridges a gap in the evolutionary history of UGTs in gymnosperms. We also discuss the implication of UGT716A1 for biosynthesis, evolution, and bioengineering of diverse glucosylated flavonoids.

  11. Probability distribution functions of turbulence in seepage-affected alluvial channel

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Anurag; Kumar, Bimlesh, E-mail: anurag.sharma@iitg.ac.in, E-mail: bimk@iitg.ac.in [Department of Civil Engineering, Indian Institute of Technology Guwahati, 781039 (India)

    2017-02-15

    The present experimental study is carried out on the probability distribution functions (PDFs) of turbulent flow characteristics within near-bed-surface and away-from-bed surfaces for both no seepage and seepage flow. Laboratory experiments were conducted in the plane sand bed for no seepage (NS), 10% seepage (10%S) and 15% seepage (15%) cases. The experimental calculation of the PDFs of turbulent parameters such as Reynolds shear stress, velocity fluctuations, and bursting events is compared with theoretical expression obtained by Gram–Charlier (GC)-based exponential distribution. Experimental observations follow the computed PDF distributions for both no seepage and seepage cases. Jensen-Shannon divergence (JSD) method is used to measure the similarity between theoretical and experimental PDFs. The value of JSD for PDFs of velocity fluctuation lies between 0.0005 to 0.003 while the JSD value for PDFs of Reynolds shear stress varies between 0.001 to 0.006. Even with the application of seepage, the PDF distribution of bursting events, sweeps and ejections are well characterized by the exponential distribution of the GC series, except that a slight deflection of inward and outward interactions is observed which may be due to weaker events. The value of JSD for outward and inward interactions ranges from 0.0013 to 0.032, while the JSD value for sweep and ejection events varies between 0.0001 to 0.0025. The theoretical expression for the PDF of turbulent intensity is developed in the present study, which agrees well with the experimental observations and JSD lies between 0.007 and 0.015. The work presented is potentially applicable to the probability distribution of mobile-bed sediments in seepage-affected alluvial channels typically characterized by the various turbulent parameters. The purpose of PDF estimation from experimental data is that it provides a complete numerical description in the areas of turbulent flow either at a single or finite number of points

  12. Natural gas seepage from a dug well in Gemerska Panica

    International Nuclear Information System (INIS)

    Milicka, J.; Pereszlenyi, M.; Masaryk, P.

    1997-01-01

    On July 20 1993, a seepage of inflammable natural gas was reported by workers of the Slovak Gas Industry enterprise (SPP) to the Oil and Gas Research and Prospecting (VVNP). Therefore, the locality was visited with the aim to evaluate the current situation, to take rock and water samples for for chemical analysis, to survey the vicinity of Gemerska Panica and to prepare a preliminary oil-geological evaluation of the area, with a suggestion of further prospecting. At the same time, the seepage of inflammable natural gas was reported to the District Mining Office in Spisska Nova Ves. (authors)

  13. Investigation of seepage under the Wenxiakou dam using radiotracer

    International Nuclear Information System (INIS)

    Li Zhangsu

    1988-01-01

    This paper describes the result of seepage observation on the dam foundation of Wenxiakou Reservoir using radioactive NaI (I-131) as a tracer. The main feature of the observing technique is to ascertain the seepages between the dam foundation and the clay core wall and around the abutment by measuring vertical flow. The results obtained from the observation have provided some important information for planning the engineering project of anti-seepage and reinforcement of the dam foundation and its right abutment. (author). 2 refs, 4 figs, 1 tab

  14. Analysis of the influence of the interlayer staggered zone in the basalt of Jinsha River Basin on the main buildings

    Science.gov (United States)

    Guo, Qiaona; Huang, Jiangwei

    2018-02-01

    In this paper, the finite element software FEFLOW is used to simulate the seepage field of the interlayer staggered zone C2 in the basalt of Jinsha River Basin. The influence of the interlayer staggered zone C2 on the building is analyzed. Combined with the waterproof effect of current design scheme of anti-seepage curtain, the seepage field in the interlayer staggered zone C2 is discussed under different design schemes. The optimal design scheme of anti-seepage curtain is put forward. The results showed that the case four can effectively reduce the head and hydraulic gradient of underground powerhouse area, and improve the groundwater seepage field in the plant area.

  15. A numerical procedure for transient free surface seepage through fracture networks

    Science.gov (United States)

    Jiang, Qinghui; Ye, Zuyang; Zhou, Chuangbing

    2014-11-01

    A parabolic variational inequality (PVI) formulation is presented for the transient free surface seepage problem defined for a whole fracture network. Because the seepage faces are specified as Signorini-type conditions, the PVI formulation can effectively eliminate the singularity of spillpoints that evolve with time. By introducing a continuous penalty function to replace the original Heaviside function, a finite element procedure based on the PVI formulation is developed to predict the transient free surface response in the fracture network. The effects of the penalty parameter on the solution precision are analyzed. A relative error formula for evaluating the flow losses at steady state caused by the penalty parameter is obtained. To validate the proposed method, three typical examples are solved. The solutions for the first example are compared with the experimental results. The results from the last two examples further demonstrate that the orientation, extent and density of fractures significantly affect the free surface seepage behavior in the fracture network.

  16. Medicago truncatula CYP716A12 is a multifunctional oxidase involved in the biosynthesis of hemolytic saponins.

    Science.gov (United States)

    Carelli, Maria; Biazzi, Elisa; Panara, Francesco; Tava, Aldo; Scaramelli, Laura; Porceddu, Andrea; Graham, Neil; Odoardi, Miriam; Piano, Efisio; Arcioni, Sergio; May, Sean; Scotti, Carla; Calderini, Ornella

    2011-08-01

    Saponins, a group of glycosidic compounds present in several plant species, have aglycone moieties that are formed using triterpenoid or steroidal skeletons. In spite of their importance as antimicrobial compounds and their possible benefits for human health, knowledge of the genetic control of saponin biosynthesis is still poorly understood. In the Medicago genus, the hemolytic activity of saponins is related to the nature of their aglycone moieties. We have identified a cytochrome P450 gene (CYP716A12) involved in saponin synthesis in Medicago truncatula using a combined genetic and biochemical approach. Genetic loss-of-function analysis and complementation studies showed that CYP716A12 is responsible for an early step in the saponin biosynthetic pathway. Mutants in CYP716A12 were unable to produce hemolytic saponins and only synthetized soyasaponins, and were thus named lacking hemolytic activity (lha). In vitro enzymatic activity assays indicate that CYP716A12 catalyzes the oxidation of β-amyrin and erythrodiol at the C-28 position, yielding oleanolic acid. Transcriptome changes in the lha mutant showed a modulation in the main steps of triterpenic saponin biosynthetic pathway: squalene cyclization, β-amyrin oxidation, and glycosylation. The analysis of CYP716A12 expression in planta is reported together with the sapogenin content in different tissues and stages. This article provides evidence for CYP716A12 being a key gene in hemolytic saponin biosynthesis.

  17. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat A.; Rodriguez, J. Alfredo; Villalba, Lourdes; de la Garza, Rodrigo

    2008-10-25

    An integrated field, laboratory, and modeling study of the Pena Blanca (Chihuahua, Mexico) natural analogue site is being conducted to evaluate processes that control the mobilization and transport of radionuclides from a uranium ore deposit. One component of this study is an evaluation of the potential for radionuclide transport through the unsaturated zone (UZ) via a seepage study in an adit at the Nopal I uranium mine, excavated 10 m below a mined level surface. Seasonal rainfall on the exposed level surface infiltrates into the fractured rhyolitic ash-flow tuff and seeps into the adit. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage within the Nopal I +00 adit. Monitoring of seepage within the adit between April 2005 and December 2006 indicates that seepage is highly heterogeneous with respect to time, location, and quantity. Within the back adit area, a few zones where large volumes of water have been collected are linked to fast flow path fractures (0-4 h transit times) presumably associated with focused flow. In most locations, however, there is a 1-6 month time lag between major precipitation events and seepage within the adit, with longer residence times observed for the front adit area. Seepage data obtained from this study will be used to provide input to flow and transport models being developed for the Nopal I hydrogeologic system.

  18. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat A.; Rodriguez, J. Alfredo; Villalba, Lourdes; de la Garza, Rodrigo

    2008-01-01

    An integrated field, laboratory, and modeling study of the Pena Blanca (Chihuahua, Mexico) natural analogue site is being conducted to evaluate processes that control the mobilization and transport of radionuclides from a uranium ore deposit. One component of this study is an evaluation of the potential for radionuclide transport through the unsaturated zone (UZ) via a seepage study in an adit at the Nopal I uranium mine, excavated 10 m below a mined level surface. Seasonal rainfall on the exposed level surface infiltrates into the fractured rhyolitic ash-flow tuff and seeps into the adit. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage within the Nopal I +00 adit. Monitoring of seepage within the adit between April 2005 and December 2006 indicates that seepage is highly heterogeneous with respect to time, location, and quantity. Within the back adit area, a few zones where large volumes of water have been collected are linked to fast flow path fractures (0-4 h transit times) presumably associated with focused flow. In most locations, however, there is a 1-6 month time lag between major precipitation events and seepage within the adit, with longer residence times observed for the front adit area. Seepage data obtained from this study will be used to provide input to flow and transport models being developed for the Nopal I hydrogeologic system.

  19. Treatment of septic tank effluents by a full-scale capillary seepage soil biofiltration system.

    Science.gov (United States)

    Fan, Chihhao; Chang, Fang-Chih; Ko, Chun-Han; Teng, Chia-Ji; Chang, Tzi-Chin; Sheu, Yiong-Shing

    2009-03-01

    The purpose of this study is to evaluate the efficiency of septic tank effluent treatment by an underground capillary seepage soil biofiltration system in a suburban area of Taipei, Taiwan. In contrast to traditional subsurface wastewater infiltration systems, capillary seepage soil biofiltration systems initially draw incoming influent upwards from the distribution pipe by capillary and siphonage actions, then spread influent throughout the soil biofiltration bed. The underground capillary seepage soil biofiltration system consists of a train of underground treatment units, including one wastewater distribution tank, two capillary seepage soil biofiltration units in series, and a discharge tank. Each capillary seepage soil biofiltration unit contains one facultative digestion tank and one set of biofiltration beds. At the flow rate of 50 m3/day, average influent concentrations of biochemical oxygen demand (BOD), suspended solid (SS), ammonia nitrogen (NH3-N), and total phosphates (TP), were 36.15 mg/L, 29.14 mg/L, 16.05 mg/L, and 1.75 mg/L, respectively. After 1.5 years of system operation, the measured influent and effluent results show that the treatment efficiencies of the soil biofiltration system for BOD, SS, NH3-N, TP, and total coliforms are 82.96%, 60.95%, 67.17%, 74.86%, and 99.99%, respectively.

  20. Interpretation of self-potential data for dam seepage investigations

    Energy Technology Data Exchange (ETDEWEB)

    Corwin, R.F.; Sheffer, M.R.; Salmon, G. [BC Hydro, Burnaby, BC (Canada)

    2007-04-15

    This book represents one of a series on the subject of geophysical methods and their use in assessing seepage and internal erosion in embankment dams. This manual facilitates the interpretation of self-potential (SP) data generated by subsurface fluid flow, with an emphasis on dam seepage studies. It is intended for users with a background in geophysics or engineering having a general familiarity with both the SP and direct-current (DC) resistivity methods and their applications. It includes an extensive reference list covering all aspects of available SP interpretation techniques, including qualitative, analytical and numerical methods. Particular emphasis is placed on the use of geometric source analytical modeling methods to evaluate SP anomalies. These methods provide a simple yet efficient means of estimating the location and depth of current sources of observed SP data, which may be linked to fluid flow in the subsurface. The manual is primarily oriented toward embankment dams and earthen structures such as levees and dikes. SP methods have been used to investigate seepage through pervious zones and cracks in concrete and concrete-faced structures. The manual describes the nature of SP fields generated by both uniform and non-uniform dam seepage flow, as well as non-seepage sources of SP variations. These methods enable the study of more complex systems and require a more comprehensive analysis of a given field site. refs., tabs., figs.

  1. 12 CFR 716.2 - Model privacy form and examples.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Model privacy form and examples. 716.2 Section... PRIVACY OF CONSUMER FINANCIAL INFORMATION § 716.2 Model privacy form and examples. (a) Model privacy form..., although use of the model privacy form is not required. (b) Examples. The examples in this part are not...

  2. Closure plan for the M-Area settling basin and vicinity at the Savannah River Plant

    International Nuclear Information System (INIS)

    Colven, W.P.; Pickett, J.B.

    1985-07-01

    The areas addressed in this closure plan include a process sewer line, surface impoundment (settling basin), overflow ditch, seepage area, and a Carolina Bay known as Lost Lake. Since it is proposed that the basin and vicinity be closed with the hazardous wastes placed and stabilized in the basin, it will be closed pursuant to regulations for closing a hazardous waste landfill. No free liquids will remain in the impoundment after closure is completed

  3. 12 CFR Appendix B to Part 716 - SAMPLE CLAUSES

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    2010-01-01

    ...-dealers, and insurance agents”]; • Non-financial companies, such as [provide illustrative examples, such... CONSUMER FINANCIAL INFORMATION Pt. 716, App. B Appendix B to Part 716—SAMPLE CLAUSES This appendix only... disclose nonpublic personal information about you to the following types of third parties: • Financial...

  4. 40 CFR 716.3 - Definitions.

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    2010-07-01

    ... SAFETY DATA REPORTING General Provisions § 716.3 Definitions. The definitions in section 3 of TSCA apply... product research and development, or as an intermediate. (2) Manufacture for commercial purposes also... commit financial resources toward the manufacture, importation, or processing of a substance or mixture...

  5. 47 CFR 24.716 - Installment payments for licenses for frequency Block F.

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    2010-10-01

    ... Block F. 24.716 Section 24.716 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON....716 Installment payments for licenses for frequency Block F. Installment Payments. Each eligible licensee of frequency Block F may pay the remaining 80 percent of the net auction price for the license in...

  6. Medicago truncatula CYP716A12 Is a Multifunctional Oxidase Involved in the Biosynthesis of Hemolytic Saponins[W

    Science.gov (United States)

    Carelli, Maria; Biazzi, Elisa; Panara, Francesco; Tava, Aldo; Scaramelli, Laura; Porceddu, Andrea; Graham, Neil; Odoardi, Miriam; Piano, Efisio; Arcioni, Sergio; May, Sean; Scotti, Carla; Calderini, Ornella

    2011-01-01

    Saponins, a group of glycosidic compounds present in several plant species, have aglycone moieties that are formed using triterpenoid or steroidal skeletons. In spite of their importance as antimicrobial compounds and their possible benefits for human health, knowledge of the genetic control of saponin biosynthesis is still poorly understood. In the Medicago genus, the hemolytic activity of saponins is related to the nature of their aglycone moieties. We have identified a cytochrome P450 gene (CYP716A12) involved in saponin synthesis in Medicago truncatula using a combined genetic and biochemical approach. Genetic loss-of-function analysis and complementation studies showed that CYP716A12 is responsible for an early step in the saponin biosynthetic pathway. Mutants in CYP716A12 were unable to produce hemolytic saponins and only synthetized soyasaponins, and were thus named lacking hemolytic activity (lha). In vitro enzymatic activity assays indicate that CYP716A12 catalyzes the oxidation of β-amyrin and erythrodiol at the C-28 position, yielding oleanolic acid. Transcriptome changes in the lha mutant showed a modulation in the main steps of triterpenic saponin biosynthetic pathway: squalene cyclization, β-amyrin oxidation, and glycosylation. The analysis of CYP716A12 expression in planta is reported together with the sapogenin content in different tissues and stages. This article provides evidence for CYP716A12 being a key gene in hemolytic saponin biosynthesis. PMID:21821776

  7. Shallow rainwater lenses in deltaic areas with saline seepage

    NARCIS (Netherlands)

    Louw, de P.G.B.; Eeman, S.; Siemon, B.; `Voortman, B.R.; Gunnink, J.; Baaren, E.S.; Oude Essink, G.H.P.

    2011-01-01

    In deltaic areas with saline seepage, freshwater availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence and

  8. Shallow rainwater lenses in deltaic areas with saline seepage

    NARCIS (Netherlands)

    De Louw, Perry G.B.; Eeman, Sara; Siemon, Bernhard; Voortman, Bernard R.; Gunnink, Jan; Van Baaren, Esther S.; Oude Essink, Gualbert

    2011-01-01

    In deltaic areas with saline seepage, fresh water availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence

  9. 32 CFR 716.7 - Payment of the death gratuity.

    Science.gov (United States)

    2010-07-01

    ... certification and voucher for the death gratuity payment. The Comptroller General of the United States has... Certification and Voucher for Death Gratuity Payment, DD Form 397, in original and five copies, completing... 32 National Defense 5 2010-07-01 2010-07-01 false Payment of the death gratuity. 716.7 Section 716...

  10. SEEPAGE/BACKFILL INTERACTIONS

    International Nuclear Information System (INIS)

    Mariner, P.

    2000-01-01

    As directed by written development plan (CRWMS M andO 1999a), a sub-model of seepage/backfill interactions is developed and presented in this document to support the Engineered Barrier System (EBS) Physical and Chemical Environment Model. The purpose of this analysis is to assist Performance Assessment Operations (PAO) and the Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift. In this analysis, a conceptual model is developed to provide PAO a more detailed and complete in-drift geochemical model abstraction and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). The development plan calls for a sub-model that evaluates the effect on water chemistry of chemical reactions between water that enters the drift and backfill materials in the drift. The development plan specifically requests an evaluation of the following important chemical reaction processes: dissolution-precipitation, aqueous complexation, and oxidation-reduction. The development plan also requests the evaluation of the effects of varying seepage and drainage fluxes, varying temperature, and varying evaporation and condensation fluxes. Many of these effects are evaluated in a separate Analysis/Model Report (AMR), ''Precipitates Salts Analysis AMR'' (CRWMS M andO 2000), so the results of that AMR are referenced throughout this AMR

  11. SEEPAGE/BACKFILL INTERACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    P. Mariner

    2000-04-14

    As directed by written development plan (CRWMS M&O 1999a), a sub-model of seepage/backfill interactions is developed and presented in this document to support the Engineered Barrier System (EBS) Physical and Chemical Environment Model. The purpose of this analysis is to assist Performance Assessment Operations (PAO) and the Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift. In this analysis, a conceptual model is developed to provide PAO a more detailed and complete in-drift geochemical model abstraction and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). The development plan calls for a sub-model that evaluates the effect on water chemistry of chemical reactions between water that enters the drift and backfill materials in the drift. The development plan specifically requests an evaluation of the following important chemical reaction processes: dissolution-precipitation, aqueous complexation, and oxidation-reduction. The development plan also requests the evaluation of the effects of varying seepage and drainage fluxes, varying temperature, and varying evaporation and condensation fluxes. Many of these effects are evaluated in a separate Analysis/Model Report (AMR), ''Precipitates Salts Analysis AMR'' (CRWMS M&O 2000), so the results of that AMR are referenced throughout this AMR.

  12. 32 CFR 716.10 - Procedures.

    Science.gov (United States)

    2010-07-01

    ... receipt, the disbursing officer will furnish the Navy Finance Center, Cleveland, Ohio 44199, with the decedent's basic monthly pay [plus any special (see § 716.1), incentive, and proficiency pay] in the event... there. The CACP officer shall also send a copy of his message to the Navy Finance Center with the...

  13. Potential Antifreeze Compounds in Present-Day Martian Seepage Groundwater

    Directory of Open Access Journals (Sweden)

    Jiin-Shuh Jean

    2008-01-01

    Full Text Available Is the recently found seepage groundwater on Mars pure H2O, or mixed with salts and other antifreeze compounds? Given the surface conditions of Mars, it is unlikely that pure water could either exist in its liquid state or have shaped Mars¡¦ fluid erosional landforms (gullies, channels, and valley networks. More likely is that Mars¡¦ seepage groundwater contains antifreeze and salt compounds that resist freezing and suppress evaporation. This model better accounts for Mars¡¦ enigmatic surface erosion. This paper suggests 17 antifreeze compounds potentially present in Martian seepage groundwater. Given their liquid state and physical properties, triethylene glycol, diethylene glycol, ethylene glycol, and 1,3-propylene glycol are advanced as the most likely candidate compounds. This paper also explores how a mixing of glycol or glycerol with salts in the Martian seepage groundwater may have lowered water¡¦s freezing point and raised its boiling point, with consequences that created fluid gully and channel erosion. Ethylene glycol and related hydrocarbon compounds have been identified in Martian and other interstellar meteorites. We suggest that these compounds and their proportions to water be included for detection in future explorations.

  14. Effects of Uncertainty and Spatial Variability on Seepage into Drifts in the Yucca Mountain Total system Performance Assessment Model

    International Nuclear Information System (INIS)

    Kalinich, D. A.; Wilson, M. L.

    2001-01-01

    Seepage into the repository drifts is an important factor in total-system performance. Uncertainty and spatial variability are considered in the seepage calculations. The base-case results show 13.6% of the waste packages (WPs) have seepage. For 5th percentile uncertainty, 4.5% of the WPs have seepage and the seepage flow decreased by a factor of 2. For 95th percentile uncertainty, 21.5% of the WPs have seepage and the seepage flow increased by a factor of 2. Ignoring spatial variability resulted in seepage on 100% of the WPs, with a factor of 3 increase in the seepage flow

  15. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    International Nuclear Information System (INIS)

    Dixon, P.

    2004-01-01

    The purpose of this Model Report (REV02) is to document the unsaturated zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrological-chemical (THC) processes on UZ flow and transport. This Model Report has been developed in accordance with the ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (Bechtel SAIC Company, LLC (BSC) 2002 [160819]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this Model Report in Section 1.12, Work Package AUZM08, ''Coupled Effects on Flow and Seepage''. The plan for validation of the models documented in this Model Report is given in Attachment I, Model Validation Plans, Section I-3-4, of the TWP. Except for variations in acceptance criteria (Section 4.2), there were no deviations from this TWP. This report was developed in accordance with AP-SIII.10Q, ''Models''. This Model Report documents the THC Seepage Model and the Drift Scale Test (DST) THC Model. The THC Seepage Model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC model is a drift-scale process model relying on the same conceptual model and much of the same input data (i.e., physical, hydrological, thermodynamic, and kinetic) as the THC Seepage Model. The DST THC Model is the primary method for validating the THC Seepage Model. The DST THC Model compares predicted water and gas compositions, as well as mineral alteration patterns, with observed data from the DST. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal-loading conditions, and predict the evolution of mineral alteration and fluid chemistry around potential waste emplacement drifts. The DST THC Model is used solely for the validation of the THC

  16. Shallow rainwater lenses in deltaic areas with saline seepage

    Directory of Open Access Journals (Sweden)

    P. G. B. de Louw

    2011-12-01

    Full Text Available In deltaic areas with saline seepage, freshwater availability is often limited to shallow rainwater lenses lying on top of saline groundwater. Here we describe the characteristics and spatial variability of such lenses in areas with saline seepage and the mechanisms that control their occurrence and size. Our findings are based on different types of field measurements and detailed numerical groundwater models applied in the south-western delta of the Netherlands. By combining the applied techniques we could extrapolate measurements at point scale (groundwater sampling, temperature and electrical soil conductivity (TEC-probe measurements, electrical cone penetration tests (ECPT to field scale (continuous vertical electrical soundings (CVES, electromagnetic survey with EM31, and even to regional scale using helicopter-borne electromagnetic measurements (HEM. The measurements show a gradual mixing zone between infiltrating fresh rainwater and upward flowing saline groundwater. The mixing zone is best characterized by the depth of the centre of the mixing zone Dmix, where the salinity is half that of seepage water, and the bottom of the mixing zone Bmix, with a salinity equal to that of the seepage water (Cl-conc. 10 to 16 g l−1. Dmix is found at very shallow depth in the confining top layer, on average at 1.7 m below ground level (b.g.l., while Bmix lies about 2.5 m b.g.l. The model results show that the constantly alternating upward and downward flow at low velocities in the confining layer is the main mechanism of mixing between rainwater and saline seepage and determines the position and extent of the mixing zone (Dmix and Bmix. Recharge, seepage flux, and drainage depth are the controlling factors.

  17. The Gela Basin pockmark field in the strait of Sicily (Mediterranean Sea: chemosymbiotic faunal and carbonate signatures of postglacial to modern cold seepage

    Directory of Open Access Journals (Sweden)

    M. Taviani

    2013-07-01

    Full Text Available The geo-biological exploration of a pockmark field located at ca. 800 m below sea level in the Gela basin (Strait of Sicily, Central Mediterranean provided a relatively diverse chemosymbiotic community and methane-imprinted carbonates. To date, this is the first occurrence of such a type of specialised deep-water cold-seep communities recorded from this key region, before documented in the Mediterranean as rather disjunct findings in its eastern and westernmost basins. The thiotrophic chemosymbiotic organisms recovered from this area include empty tubes of the vestimentiferan Lamellibrachia sp., loose and articulated shells of lucinids (Lucinoma kazani, Myrtea amorpha, vesicomyids (Isorropodon perplexum, and gastropods (Taranis moerchii. A callianassid decapod (Calliax sp. was consistently found alive in large numbers in the pockmark mud. Their post-mortem calcified parts mixed with molluscs and subordinately miliolid foraminifers form a distinct type of skeletal assemblage. Carbonate concretions display δ13C values as low as −40‰ PDB suggesting the occurrence of light hydrocarbons in the seeping fluids. Since none of the truly chemosymbiotic organisms was found alive, although their skeletal parts appear at times very fresh, some specimens have been AMS-14C dated to shed light on the historical evolution of this site. Lamellibrachiav and Lucinoma are two of the most significant chemosymbiotic taxa reported from various Mediterranean cold seep sites (Alboran Sea and Eastern basin. Specimens from station MEDCOR78 (pockmark #1, Lat. 36°46´10.18" N, Long. 14°01´31.59" E, 815 m below sea level provided ages of 11736 ± 636 yr cal BP (Lamellibrachia sp., and 9609.5 ± 153.5 yr cal BP (L. kazani. One shell of M. amorpha in core MEDCOR81 (pockmark #6, Lat 36°45´38.89" N, Long 14°00´07.58" E, 822 m below sea level provided a sub-modern age of 484 ± 54 yr cal BP. These ages document that fluid seepage at this pockmark site has been

  18. Mapping on Slope Seepage Problem using Electrical Resistivity Imaging (ERI)

    Science.gov (United States)

    Hazreek, Z. A. M.; Nizam, Z. M.; Aziman, M.; Dan, M. F. Md; Shaylinda, M. Z. N.; Faizal, T. B. M.; Aishah, M. A. N.; Ambak, K.; Rosli, S.; Rais, Y.; Ashraf, M. I. M.; Alel, M. N. A.

    2018-04-01

    The stability of slope may influenced by several factors such as its geomaterial properties, geometry and environmental factors. Problematic slope due to seepage phenomenon will influenced the slope strength thus promoting to its failure. In the past, slope seepage mapping suffer from several limitation due to cost, time and data coverage. Conventional engineering tools to detect or mapped the seepage on slope experienced those problems involving large and high elevation of slope design. As a result, this study introduced geophysical tools for slope seepage mapping based on electrical resistivity method. Two spread lines of electrical resistivity imaging were performed on the slope crest using ABEM SAS 4000 equipment. Data acquisition configuration was based on long and short arrangement, schlumberger array and 2.5 m of equal electrode spacing interval. Raw data obtained from data acquisition was analyzed using RES2DINV software. Both of the resistivity results show that the slope studied consists of three different anomalies representing top soil (200 – 1000 Ωm), perched water (10 – 100 Ωm) and hard/dry layer (> 200 Ωm). It was found that seepage problem on slope studied was derived from perched water zones with electrical resistivity value of 10 – 100 Ωm. Perched water zone has been detected at 6 m depth from the ground level with varying thickness at 5 m and over. Resistivity results have shown some good similarity output with reference to borehole data, geological map and site observation thus verified the resistivity results interpretation. Hence, this study has shown that the electrical resistivity imaging was applicable in slope seepage mapping which consider efficient in term of cost, time, data coverage and sustainability.

  19. Testing and modeling of seepage into underground openings in a heterogeneous fracture system at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Ahlers, C.F.; Trautz, R.C.; Cook, P.J.; Finsterle, S.

    2002-01-01

    We discuss field activities designed to characterize seepage into an underground opening at the potential site for geologic storage of high-level radioactive waste (HLRW) at Yucca Mountain, Nevada, and the use of these data for development and calibration of a model for predicting seepage into planned HLRW emplacement drifts. Air-injection tests were conducted to characterize the permeability of the fractured rock, and liquid-release tests (LRTs) were conducted and seepage monitored to characterize the seepage-relevant properties of the fractured rock. Both air-injection and liquid-release tests were performed in the same borehole intervals, located above the underground openings. For modeling, three-dimensional, heterogeneous permeability fields were generated, conditioned on the air-permeability data. The initial seepage data collected were used to calibrate the model and test the appropriateness of the modeling approach. A capillary-strength parameter and porosity were the model parameters selected for estimation by data inversion. However, due to the short-term nature of the initial data, the inversion process was unable to independently determine the capillary strength and porosity of the fractured rock. Subsequent seepage data collection focused on longer-term tests, a representative selection of which was used for data inversion. Field observations also played a key role by identifying factors such as evaporation and ceiling geometry that can enhance or reduce seepage. These observations help guide future test and model development by ensuring that relevant processes that influence seepage are identified, characterized, and incorporated into the model, thus increasing confidence in the parameter estimates. It is this iterative and collaborative approach to field testing and modeling, and the feedback mechanisms of field-test-methodology and model review and revision, that has been employed to continuously improve the scientific quality of the study

  20. 12 CFR 716.16 - Protection of Fair Credit Reporting Act.

    Science.gov (United States)

    2010-01-01

    ... PRIVACY OF CONSUMER FINANCIAL INFORMATION Relation to Other Laws; Effective Date § 716.16 Protection of Fair Credit Reporting Act. Nothing in this part shall be construed to modify, limit, or supersede the... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Protection of Fair Credit Reporting Act. 716.16...

  1. Geophysical investigation of seepage beneath an earthen dam.

    Science.gov (United States)

    Ikard, S J; Rittgers, J; Revil, A; Mooney, M A

    2015-01-01

    A hydrogeophysical survey is performed at small earthen dam that overlies a confined aquifer. The structure of the dam has not shown evidence of anomalous seepage internally or through the foundation prior to the survey. However, the surface topography is mounded in a localized zone 150 m downstream, and groundwater discharges from this zone periodically when the reservoir storage is maximum. We use self-potential and electrical resistivity tomography surveys with seismic refraction tomography to (1) determine what underlying hydrogeologic factors, if any, have contributed to the successful long-term operation of the dam without apparent indicators of anomalous seepage through its core and foundation; and (2) investigate the hydraulic connection between the reservoir and the seepage zone to determine whether there exists a potential for this success to be undermined. Geophysical data are informed by hydraulic and geotechnical borehole data. Seismic refraction tomography is performed to determine the geometry of the phreatic surface. The hydro-stratigraphy is mapped with the resistivity data and groundwater flow patterns are determined with self-potential data. A self-potential model is constructed to represent a perpendicular profile extending out from the maximum cross-section of the dam, and self-potential data are inverted to recover the groundwater velocity field. The groundwater flow pattern through the aquifer is controlled by the bedrock topography and a preferential flow pathway exists beneath the dam. It corresponds to a sandy-gravel layer connecting the reservoir to the downstream seepage zone. © 2014, National Ground Water Association.

  2. 40 CFR 716.20 - Studies not subject to the reporting requirements.

    Science.gov (United States)

    2010-07-01

    ...) For the listed chemicals under § 716.120(d) in the category “OSHA Chemicals in Need of Dermal Absorption Testing,” studies on ecological effects. (4) For the chemicals listed at § 716.120 with a special... percent of the mixture, except when a purpose of the study includes the investigation of the effects of...

  3. COMPREHENSIVE ANALYSIS ON SEEPAGE AND STRUCTURAL STABILITY OF EARTH-ROCK DAM: A CASE STUDY OF XIQUANYAN DAM IN CHINA

    Directory of Open Access Journals (Sweden)

    Qingqing GUO

    2016-07-01

    Full Text Available Earth-rock dam is commonly used in the high-dam engineering around the world. It has been widely accepted that the analysis on structural and seepage stability plays a very important role, and it is necessary to take into account while designing the earth-rock dam. In performing the analysis of structural and seepage stability, many remarkable methods are available at current stage. However, there are still some important issues remaining unsolved, including: (1 Finite element methods (FEMs is a means of solutions to analysis seepage process, but it is often a difficult task to determine the so-called seepage coefficient, because the common-used water injection test is limited in the practical work due to the high cost and complex procedure. (2 It has long been discussed that the key parameters for structural stability analysis show a significant spatial and temporal variations. It may be partly explained by the inhomogeneous dam-filling during construction work and the developing seepage process. The consequence is that one constant value of the parameter cannot represent the above variations. In this context, we solve the above issues and introduce the solution with a practical earth-rock dam project. For determining the seepage coefficient, the data from the piezo metric tube is used to calculate the potential value, based on which the seepage coefficient can be back-analysed. Then the seepage field, as well as the seepage stability are numerically analysed using the FEM-based SEEP/W program. As to the structural safety, we take into account the spatial and temporal variations of the key parameters, and incorporate the Monte-Carlo simulation method into the commonly used M-P method to calculate the frequency distribution of the obtained structural safety factor. In this way, the structural and seepage safety can be well analysed. This study is also beneficial to provide a mature method and a theoretical insight into the earth-rock dam design

  4. Mapping seepage through the River Reservoir Dam near Eagar, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Rollins, P.

    2005-06-30

    This article describes the actions taken to address an unusual amount of water seepage from the left abutment weir-box of the River Reservoir dam built in 1896 near Eagar, Arizona. Upon noting the seepage in March 2004, the operator, Round Valley Water Users Association, contacted the State of Arizona who funded the investigation and subsequent remediation activities through an emergency fund. The dam was originally built with local materials and did not include a clay core. It was modified at least four times. The embankment sits on basalt bedrock and consists of clayey soils within a rock-fill shell. AquaTrack technology developed by Willowstick Technologies was used to assess the deteriorating situation. AquaTrack uses a low voltage, low amperage audio-frequency electrical current to energize the groundwater or seepage. This made it possible to follow the path of groundwater between the electrodes. A magnetic field was created which made it possible to locate and map the field measurements. The measured magnetic field data was processed, contoured and correlated to other hydrogeologic information. This identified the extent and preferential flow paths of the seepage. The survey pinpointed the area with the greatest leakage in both the horizontal and vertical directions. Fluorescent dyes were also used for tracer work to confirm previous findings that showed a serious seepage problem. The water of the reservoir was lowered to perform remedial measures to eliminate the risk of immediate failure. Funding for a more permanent repair is pending. 10 figs.

  5. Application of carbon isotopes to detect seepage out of coalbed natural gas produced water impoundments

    International Nuclear Information System (INIS)

    Sharma, Shikha; Baggett, Joshua K.

    2011-01-01

    Highlights: → Coalbed natural gas extraction results in large amount of produced water. → Risk of deterioration of ambient water quality. → Carbon isotope natural tracer for detecting seepage from produced water impoundments. - Abstract: Coalbed natural gas (CBNG) production from coal bed aquifers requires large volumes of produced water to be pumped from the subsurface. The produced water ranges from high quality that meets state and federal drinking water standards to low quality due to increased salinity and/or sodicity. The Powder River Basin of northeastern Wyoming is a major coalbed natural gas producing region, where water quality generally decreases moving from the southeastern portion of the basin towards the center. Most produced water in Wyoming is disposed into impoundments and other surface drainages, where it may infiltrate into shallow groundwater. Groundwater degradation caused by infiltration of CBNG produced water holding impoundments into arid, soluble salt-rich soils is an issue of immense importance because groundwater is a major source for stock water, irrigation, and drinking water for many small communities in these areas. This study examines the potential of using stable C isotope signatures of dissolved inorganic C (δ 13 C DIC ) to track the fate of CBNG produced water after it is discharged into the impoundments. Other geochemical proxies like the major cations and major anions were used in conjunction with field water quality measurements to understand the geochemical differences between CBNG produced waters and ambient waters in the study area. Samples were collected from the CBNG discharge outfalls, produced water holding impoundments, and monitoring wells from different parts of the Powder River Basin and analyzed for δ 13 C DIC . The CBNG produced waters from outfalls and impoundments have positive δ 13 C DIC values that fall within the range of +12 per mille to +22 per mille, distinct from the ambient regional surface and

  6. Distributed optical fiber-based monitoring approach of spatial seepage behavior in dike engineering

    Science.gov (United States)

    Su, Huaizhi; Ou, Bin; Yang, Lifu; Wen, Zhiping

    2018-07-01

    The failure caused by seepage is the most common one in dike engineering. As to the characteristics of seepage in dike, such as longitudinal extension engineering, the randomness, strong concealment and small initial quantity order, by means of distributed fiber temperature sensor system (DTS), adopting an improved optical fiber layer layout scheme, the location of initial interpolation point of the saturation line is obtained. With the barycentric Lagrange interpolation collocation method (BLICM), the infiltrated surface of dike full-section is generated. Combined with linear optical fiber monitoring seepage method, BLICM is applied in an engineering case, which shows that a real-time seepage monitoring technique is presented in full-section of dike based on the combination method.

  7. Study of seepage losses from irrigation canals using radioactive tracer technique

    International Nuclear Information System (INIS)

    Ahmad, M.; Tariq, J.A.; Rashid, A.; Rafiq, M.; Iqbal, N.

    2004-06-01

    Pakistan has an intricate irrigation system comprising a huge network of canals. A significant fraction of water in irrigation canals is lost through seepage, which is further responsible for water logging and salinity in some areas. Government is considering lining of irrigation canals to overcome this twin menace. Due to involvement of huge costs, highly pervious sections where the seepage rate is appreciably high, are needed to be identified for planning and execution of remedial actions to eliminate or minimize seepage losses. The conventional methods of measuring seepage rate from canals are limited to 'ponding' and 'inflow-outflow' methods. The ponding method is usually restricted to small canals because of the costly bulkheads and water requirement, unaffordable closure of canal, non representation of the line source and variation in the rate of seepage loss with time due to the sealing effects of fine sediments settling out. Inaccurate measurement of discharge under field conditions and complication due to diversion do not favour the inflow-outflow method. It is believed that the analytical methods represent the most accurate and convenient means of determining seepage values using accurate insitu hydraulic conductivity of the subsoil determined by radiotracer, geometry of the canal and position of the groundwater. As a practical application, radiotracer experiments were carried out at Rakh branch canal near Sukhiki, District Hafizabad (Punjab) to determine groundwater filtration velocity by single well point dilution technique using Technetium-99m (sup 99m/Tc) radioactive tracer, Hydraulic conductivity (determined from filtration velocity and hydraulic gradient) and canal parameters were used in the parametric equation of parachute curve to estimate the seepage rate. The average seepage rate was 4.05 cubic meter per day per meter length of the canal (equivalent to 3.795 cusec per million square feet or 1.157 cumec per second per million square meter of

  8. Infiltration and Seepage Through Fractured Welded Tuff

    Energy Technology Data Exchange (ETDEWEB)

    T.A. Ghezzehei; P.F. Dobson; J.A. Rodriguez; P.J. Cook

    2006-06-20

    The Nopal I mine in Pena Blanca, Chihuahua, Mexico, contains a uranium ore deposit within fractured tuff. Previous mining activities exposed a level ground surface 8 m above an excavated mining adit. In this paper, we report results of ongoing research to understand and model percolation through the fractured tuff and seepage into a mined adit both of which are important processes for the performance of the proposed nuclear waste repository at Yucca Mountain. Travel of water plumes was modeled using one-dimensional numerical and analytical approaches. Most of the hydrologic properly estimates were calculated from mean fracture apertures and fracture density. Based on the modeling results, we presented constraints for the arrival time and temporal pattern of seepage at the adit.

  9. Infiltration and Seepage Through Fractured Welded Tuff

    International Nuclear Information System (INIS)

    T.A. Ghezzehei; P.F. Dobson; J.A. Rodriguez; P.J. Cook

    2006-01-01

    The Nopal I mine in Pena Blanca, Chihuahua, Mexico, contains a uranium ore deposit within fractured tuff. Previous mining activities exposed a level ground surface 8 m above an excavated mining adit. In this paper, we report results of ongoing research to understand and model percolation through the fractured tuff and seepage into a mined adit both of which are important processes for the performance of the proposed nuclear waste repository at Yucca Mountain. Travel of water plumes was modeled using one-dimensional numerical and analytical approaches. Most of the hydrologic properly estimates were calculated from mean fracture apertures and fracture density. Based on the modeling results, we presented constraints for the arrival time and temporal pattern of seepage at the adit

  10. Seepage into an Underground Opening Constructed in Unsaturated Fractured Rock Under Evaporative Conditions, RPR 29013(C)

    International Nuclear Information System (INIS)

    Trautz, R. C.; Wang, Joseph S. Y.

    2001-01-01

    Liquid-release tests, performed in boreholes above an underground opening constructed in unsaturated fractured rock, are used in this study to evaluate seepage into a waste emplacement drift. Evidence for the existence of a capillary barrier at the ceiling of the drift is presented, based on field observations (including spreading of the wetting front across the ceiling and water movement up fractures exposed in the ceiling before seepage begins). The capillary barrier mechanism has the potential to divert water around the opening, resulting in no seepage when the percolation flux is at or below the seepage threshold flux. Liquid-release tests are used to demonstrate that a seepage threshold exists and to measure the magnitude of the seepage threshold flux for three test zones that seeped. The seepage data are interpreted using analytical techniques to estimate the test-specific strength of the rock capillary forces (α -1 ) that prevent water from seeping into the drift. Evaporation increases the seepage threshold flux making it more difficult for water to seep into the drift and producing artificially inflated α -1 values. With adjustments for evaporation, the minimum test-specific threshold is 1,600 mm/yr with a corresponding α -1 of 0.027 m

  11. Seepage Flow Model and Deformation Properties of Coastal Deep Foundation Pit under Tidal Influence

    Directory of Open Access Journals (Sweden)

    Shu-chen Li

    2018-01-01

    Full Text Available As the coastal region is the most developed region in China, an increasing number of engineering projects are under construction in it in recent years. However, the quality of these projects is significantly affected by groundwater, which is influenced by tidal variations. Therefore, the regional groundwater dynamic characteristics under tidal impact and the spatiotemporal evolution of the seepage field must be considered in the construction of the projects. Then, Boussinesq function was introduced into the research to deduce the seepage equation under tidal influence for the coastal area. To determine the spatiotemporal evolution of the deep foundation pit seepage field and the coastal seepage field evolution model, numerical calculations based on changes in the tidal water level and seepage equation were performed using MATLAB. According to the developed model, the influence of the seepage field on the foundation pit supporting structure in the excavation process was analyzed through numerical simulations. The results of this research could be considered in design and engineering practice.

  12. Combined use of thermal methods and seepage meters to efficiently locate, quantify, and monitor focused groundwater discharge to a sand-bed stream

    Science.gov (United States)

    Rosenberry, Donald O.; Briggs, Martin A.; Delin, Geoffrey N.; Hare, Danielle K.

    2016-01-01

    Quantifying flow of groundwater through streambeds often is difficult due to the complexity of aquifer-scale heterogeneity combined with local-scale hyporheic exchange. We used fiber-optic distributed temperature sensing (FO-DTS), seepage meters, and vertical temperature profiling to locate, quantify, and monitor areas of focused groundwater discharge in a geomorphically simple sand-bed stream. This combined approach allowed us to rapidly focus efforts at locations where prodigious amounts of groundwater discharged to the Quashnet River on Cape Cod, Massachusetts, northeastern USA. FO-DTS detected numerous anomalously cold reaches one to several m long that persisted over two summers. Seepage meters positioned upstream, within, and downstream of 7 anomalously cold reaches indicated that rapid groundwater discharge occurred precisely where the bed was cold; median upward seepage was nearly 5 times faster than seepage measured in streambed areas not identified as cold. Vertical temperature profilers deployed next to 8 seepage meters provided diurnal-signal-based seepage estimates that compared remarkably well with seepage-meter values. Regression slope and R2 values both were near 1 for seepage ranging from 0.05 to 3.0 m d−1. Temperature-based seepage model accuracy was improved with thermal diffusivity determined locally from diurnal signals. Similar calculations provided values for streambed sediment scour and deposition at subdaily resolution. Seepage was strongly heterogeneous even along a sand-bed river that flows over a relatively uniform sand and fine-gravel aquifer. FO-DTS was an efficient method for detecting areas of rapid groundwater discharge, even in a strongly gaining river, that can then be quantified over time with inexpensive streambed thermal methods.

  13. Steady flow rate to a partially penetrating well with seepage face in an unconfined aquifer

    Science.gov (United States)

    Behrooz-Koohenjani, Siavash; Samani, Nozar; Kompani-Zare, Mazda

    2011-06-01

    The flow rate to fully screened, partially penetrating wells in an unconfined aquifer is numerically simulated using MODFLOW 2000, taking into account the flow from the seepage face and decrease in saturated thickness of the aquifer towards the well. A simple three-step method is developed to find the top of the seepage face and hence the seepage-face length. The method is verified by comparing it with the results of previous predictive methods. The results show that the component of flow through the seepage face can supply a major portion of the total pumping rate. Variations in flow rate as a function of the penetration degree, elevation of the water level in the well and the distance to the far constant head boundary are investigated and expressed in terms of dimensionless curves and equations. These curves and equations can be used to design the degree of penetration for which the allowable steady pumping rate is attained for a given elevation of water level in the well. The designed degree of penetration or flow rate will assure the sustainability of the aquifer storage, and can be used as a management criterion for issuing drilling well permits by groundwater protection authorities.

  14. SEEPAGE INTO DRIFTS IN UNSATRUATED FRACTURED ROCK AT YUCCA MOUNTAIN

    International Nuclear Information System (INIS)

    JENS BIRHOLZER; GUOMIN LI; CHIN-FU TSANG; YVONNE TSANG

    1998-01-01

    An important issue for the long-term performance of underground nuclear waste repositories is the rate of seepage into the waste emplacement drifts. A prediction of the future seepage rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, as it is located in thick, partially saturated, fractured tuff formations. The long-term situation in the drifts several thousand years after waste emplacement will be characterized by a relative humidity level close to or equal to 100%. as the drifts will be sealed and unventilated, and the waste packages will have cooled. The underground tunnels will then act as capillary barriers for the unsaturated flow, ideally diverting water around them, if the capillary forces are stronger than gravity and viscous forces. Seepage into the drifts will only be possible if the hydraulic pressure in the rock close to the drift walls increases to positive values; i.e., the flow field becomes locally saturated. In the present work, we have developed and applied a methodology to study the potential rate of seepage into underground cavities embedded in a variably saturated, heterogeneous fractured rock formation. The fractured rock mass is represented as a stochastic continuum where the fracture permeabilities vary by several orders of magnitude. Three different realizations of random fracture permeability fields are generated, with the random permeability structure based on extensive fracture mapping, borehole video analysis, and in-situ air permeability testing. A 3-D numerical model is used to simulate the heterogeneous steady-state flow field around the drift, with the drift geometry explicitly represented within the numerical discretization grid. A variety of flow scenarios are considered assuming present-day and future climate conditions at Yucca Mountain. The numerical study is complemented by theoretical evaluations of the drift seepage problem, using stochastic perturbation theory to develop a better

  15. Calcareous forest seepages acting as biodiversity hotspots and refugia for woodland snail faunas

    Science.gov (United States)

    Horsák, Michal; Tajovská, Eva; Horsáková, Veronika

    2017-07-01

    Land-snail species richness has repeatedly been found to increase with the increasing site calcium content and humidity. These two factors, reported as the main drivers of land-snail assemblage diversity, are also among the main habitat characteristics of calcareous seepages. Here we explore local species richness and compositional variation of forest spring-fed patches (i.e. seepages), to test the hypothesis that these habitats might act as biodiversity hotspots and refugia of regional snail faunas. In contrast to treeless spring fens, only little is known about land snail faunas inhabiting forest seepages. Studying 25 isolated calcareous forest seepages, evenly distributed across the White Carpathians Protected Landscape Area (SE Czech Republic), we found that these sites, albeit spatially very limited, can harbour up to 66% of the shelled land-snail species known to occur in this well-explored protected area (in total 83 species). By comparing land snail assemblages of the studied seepages with those occurring in the woodland surroundings of each site as well as those previously sampled in 28 preserved forest sites within the study area, we found the seepages to be among the most species rich sites. Although the numbers of species did not statistically differ among these three systems, we found highly significant differences in species composition. Seepage faunas were composed of many species significantly associated with spring sites, in contrast to the assemblages of both surrounding and preserved forest sites. Our results highly support the hypothesis that calcareous forest seepages might serve as refugia and biodiversity hotspots of regional land snail faunas. Protection of these unique habitats challenges both conservation plans and forest management guidelines as they might act as sources for the recolonization and restoration of forest snail assemblages particularly in areas impoverished by harvesting and clearcutting.

  16. A Model of Anisotropic Property of Seepage and Stress for Jointed Rock Mass

    Directory of Open Access Journals (Sweden)

    Pei-tao Wang

    2013-01-01

    Full Text Available Joints often have important effects on seepage and elastic properties of jointed rock mass and therefore on the rock slope stability. In the present paper, a model for discrete jointed network is established using contact-free measurement technique and geometrical statistic method. A coupled mathematical model for characterizing anisotropic permeability tensor and stress tensor was presented and finally introduced to a finite element model. A case study of roadway stability at the Heishan Metal Mine in Hebei Province, China, was performed to investigate the influence of joints orientation on the anisotropic properties of seepage and elasticity of the surrounding rock mass around roadways in underground mining. In this work, the influence of the principal direction of the mechanical properties of the rock mass on associated stress field, seepage field, and damage zone of the surrounding rock mass was numerically studied. The numerical simulations indicate that flow velocity, water pressure, and stress field are greatly dependent on the principal direction of joint planes. It is found that the principal direction of joints is the most important factor controlling the failure mode of the surrounding rock mass around roadways.

  17. 12 CFR 716.13 - Exception to opt out requirements for service providers and joint marketing.

    Science.gov (United States)

    2010-01-01

    ... section may include marketing of your own products or services or marketing of financial products or... providers and joint marketing. 716.13 Section 716.13 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS PRIVACY OF CONSUMER FINANCIAL INFORMATION Exceptions § 716.13 Exception to...

  18. Methane Seepage on Mars: Where to Look and Why.

    Science.gov (United States)

    Oehler, Dorothy Z; Etiope, Giuseppe

    2017-12-01

    Methane on Mars is a topic of special interest because of its potential association with microbial life. The variable detections of methane by the Curiosity rover, orbiters, and terrestrial telescopes, coupled with methane's short lifetime in the martian atmosphere, may imply an active gas source in the planet's subsurface, with migration and surface emission processes similar to those known on Earth as "gas seepage." Here, we review the variety of subsurface processes that could result in methane seepage on Mars. Such methane could originate from abiotic chemical reactions, thermogenic alteration of abiotic or biotic organic matter, and ancient or extant microbial metabolism. These processes can occur over a wide range of temperatures, in both sedimentary and igneous rocks, and together they enhance the possibility that significant amounts of methane could have formed on early Mars. Methane seepage to the surface would occur preferentially along faults and fractures, through focused macro-seeps and/or diffuse microseepage exhalations. Our work highlights the types of features on Mars that could be associated with methane release, including mud-volcano-like mounds in Acidalia or Utopia; proposed ancient springs in Gusev Crater, Arabia Terra, and Valles Marineris; and rims of large impact craters. These could have been locations of past macro-seeps and may still emit methane today. Microseepage could occur through faults along the dichotomy or fractures such as those at Nili Fossae, Cerberus Fossae, the Argyre impact, and those produced in serpentinized rocks. Martian microseepage would be extremely difficult to detect remotely yet could constitute a significant gas source. We emphasize that the most definitive detection of methane seepage from different release candidates would be best provided by measurements performed in the ground or at the ground-atmosphere interface by landers or rovers and that the technology for such detection is currently available. Key

  19. A method for estimating spatially variable seepage and hydrualic conductivity in channels with very mild slopes

    Science.gov (United States)

    Shanafield, Margaret; Niswonger, Richard G.; Prudic, David E.; Pohll, Greg; Susfalk, Richard; Panday, Sorab

    2014-01-01

    Infiltration along ephemeral channels plays an important role in groundwater recharge in arid regions. A model is presented for estimating spatial variability of seepage due to streambed heterogeneity along channels based on measurements of streamflow-front velocities in initially dry channels. The diffusion-wave approximation to the Saint-Venant equations, coupled with Philip's equation for infiltration, is connected to the groundwater model MODFLOW and is calibrated by adjusting the saturated hydraulic conductivity of the channel bed. The model is applied to portions of two large water delivery canals, which serve as proxies for natural ephemeral streams. Estimated seepage rates compare well with previously published values. Possible sources of error stem from uncertainty in Manning's roughness coefficients, soil hydraulic properties and channel geometry. Model performance would be most improved through more frequent longitudinal estimates of channel geometry and thalweg elevation, and with measurements of stream stage over time to constrain wave timing and shape. This model is a potentially valuable tool for estimating spatial variability in longitudinal seepage along intermittent and ephemeral channels over a wide range of bed slopes and the influence of seepage rates on groundwater levels.

  20. Results of a seepage investigation at Bear Creek Valley, Oak Ridge, Tennessee, January through September 1994

    International Nuclear Information System (INIS)

    Robinson, J.A.; Johnson, G.C.

    1996-01-01

    A seepage investigation was conducted of 4,600 acres of Bear Creek Valley southwest of the Y-12 Plant, Oak Ridge, Tennessee, for the period of January through September 1994. The data was collected to help the Y-12 Environmental Restoration Program develop a better understanding of ground-water and surface-water interactions, recharge and discharge relations, and ground-water flow patterns. The project was divided into three phases: a reconnaissance and mapping of seeps, springs, and stream-measurement sites; a high base flow seepage investigation; and a low base flow seepage investigation. This report describes the results of the investigation. It includes a map showing measurement site locations and tables that list the coordinates for each site and measurements of discharge, pH, specific conductance, temperature, and dissolved oxygen

  1. Modelling stream aquifer seepage in an alluvial aquifer: an improved loosing-stream package for MODFLOW

    Science.gov (United States)

    Osman, Yassin Z.; Bruen, Michael P.

    2002-07-01

    Seepage from a stream, which partially penetrates an unconfined alluvial aquifer, is studied for the case when the water table falls below the streambed level. Inadequacies are identified in current modelling approaches to this situation. A simple and improved method of incorporating such seepage into groundwater models is presented. This considers the effect on seepage flow of suction in the unsaturated part of the aquifer below a disconnected stream and allows for the variation of seepage with water table fluctuations. The suggested technique is incorporated into the saturated code MODFLOW and is tested by comparing its predictions with those of a widely used variably saturated model, SWMS_2D simulating water flow and solute transport in two-dimensional variably saturated media. Comparisons are made of both seepage flows and local mounding of the water table. The suggested technique compares very well with the results of variably saturated model simulations. Most currently used approaches are shown to underestimate the seepage and associated local water table mounding, sometimes substantially. The proposed method is simple, easy to implement and requires only a small amount of additional data about the aquifer hydraulic properties.

  2. Assessment of waterlogging in agricultural megaprojects in the closed drainage basins of the Western Desert of Egypt

    Directory of Open Access Journals (Sweden)

    M. El Bastawesy

    2013-04-01

    Full Text Available This paper investigates the development of waterlogging in the cultivated and arable areas within typical dryland closed drainage basins (e.g. the Farafra and Baharia Oases, which are located in the Western Desert of Egypt. Multi-temporal remote sensing data of the Landsat Thematic Mapper (TM and Enhanced Thematic Mapper (ETM+ were collected and processed to detect the land cover changes; cultivations, and the extent of water ponds and seepage channels. The Shuttle Radar Topography Mission (SRTM digital elevation model (DEM has been processed to delineate the catchment morphometrical parameters (i.e. drainage networks, catchment divides and surface areas of different basins and to examine the spatial distribution of cultivated fields and their relation to the extracted drainage networks. The soil of these closed drainage basins is mainly shallow and lithic with high calcium carbonate content; therefore, the downward percolation of excess irrigation water is limited by the development of subsurface hardpan, which also saturates the upper layer of soil with water. The subsurface seepage from the newly cultivated areas in the Farafra Oasis has revealed the pattern of buried alluvial channels, which are waterlogged and outlined by the growth of diagnostic saline shrubs. Furthermore, the courses of these waterlogged channels are coinciding with their counterparts of the SRTM DEM, and the recent satellite images show that the surface playas in the downstream of these channels are partially occupied by water ponds. On the other hand, a large water pond has occupied the main playa and submerged the surrounding fields, as a large area has been cultivated within a relatively small closed drainage basin in the Baharia Oasis. The geomorphology of closed drainage basins has to be considered when planning for a new cultivation in dryland catchments to better control waterlogging hazards. The "dry-drainage" concept can be implemented as the drainage and

  3. F/H Effluent Treatment Facility. Preliminary engineering report

    International Nuclear Information System (INIS)

    1985-01-01

    The Department of Energy is currently proposing to construct the F/H ETF to process wastewater from the Separations Areas and replace the existing seepage basins. Reasons for seepage basin closure are two-fold. First, nonradioactive hazardous materials routinely discharged to the seepage basins may have adversely impacted the quality of the groundwater in the vicinity of the basins. Second, amendments to the Resource Conservation and Recovery Act (RCRA) were approved in 1984, prohibiting the discharge of hazardous wastes to unlined seepage basins after November, 1988. The F/H ETF will consist of wastewater storage facilities and a treatment plant discharging treated effluent to Upper Three Runs Creek. Seepage basin use in F and H Areas wil be discontinued after startup, allowing timely closure of these basins. 3 refs

  4. 11 CFR 7.16 - Miscellaneous statutory provisions.

    Science.gov (United States)

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Miscellaneous statutory provisions. 7.16... bribery, graft, and conflicts of interest, as appropriate to the employees concerned. (b) The prohibition... employee acting as the agent of a foreign principal registered under the Foreign Agents Registration Act...

  5. Seepage from uranium tailing ponds and its impact on ground water

    International Nuclear Information System (INIS)

    Rahn, P.H.; Mabes, D.L.

    1978-01-01

    A typical uranium mill produces about 1800 metric tons of tailing per day. An assessment of the seepage from an unlined tailing impoundment of a hypothetical mill in northwestern New Mexico indicates that about 2x10 5 m 3 /yr of water will seep over a period of 23 years. The seepage water will move vertically to the water table, and then spread out radially and ultimately downgradient with ground water. The principal dissolved contaminants in the tailing pond liquid are radium, thorium, sulfate, iron, manganese, and selenium; in addition, the liquid is acidic (pH=2). Many contaminants precipitate out as neutralization of seepage water occurs. At the termination of mill operation, radium will have advanced about 0.4 m and thorium no more than 0.1 m below the bottom of the tailing pond

  6. 24 CFR 7.16 - Responsibilities of employees.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Responsibilities of employees. 7.16... Responsibilities of employees. All employees of the Department are responsible for: (a) Being informed as to the..., females, persons with disabilities, veterans and others of diverse characteristics in the workforce, and...

  7. Characterization of Coal Micro-Pore Structure and Simulation on the Seepage Rules of Low-Pressure Water Based on CT Scanning Data

    Directory of Open Access Journals (Sweden)

    Gang Zhou

    2016-07-01

    Full Text Available This paper used the X-ray three-dimensional (3D microscope and acquired, through CT scanning, the 3D data of the long-frame coal sample from the Daliuta Coal Mine. Then, the 3D datacube reconstructed from the coal’s CT scanning data was visualized with the use of Avizo, an advanced visualization software (FEI, Hillsboro, OR, USA. By means of a gray-scale segmentation technique, the model of the coal’s micro-pore structure was extracted from the object region, and the precise characterization was then conducted. Finally, the numerical simulation on the water seepage characteristics in the coal micro-pores model under the pressure of 3 MPa was performed on the CFX platform. Results show that the seepage of low-pressure water exhibited preference to the channels with large pore radii, short paths, and short distance from the outlet. The seepage pressure of low-pressure water decreased gradually along the seepage direction, while the seepage velocity of low-pressure water decreased gradually along the direction from the pore center to the wall. Regarding the single-channel seepage behaviors, the seepage velocity and mass flow rate of water seepage in the X direction were the largest, followed by the values of the seepage in the Y direction, and the seepage velocity and mass flow rate of water seepage in the Z direction were the smallest. Compared with the results in single-channel seepage, the dual-channel seepage in the direction of (X + Y and the multi-channel seepage in the direction of (X + Y + Z exhibited significant increases in the overall seepage velocity. The present study extends the application of 3D CT scanning data and provides a new idea and approach for exploring the seepage rules in coal micro-pore structures.

  8. Evaluation of seepage and discharge uncertainty in the middle Snake River, southwestern Idaho

    Science.gov (United States)

    Wood, Molly S.; Williams, Marshall L.; Evetts, David M.; Vidmar, Peter J.

    2014-01-01

    The U.S. Geological Survey, in cooperation with the State of Idaho, Idaho Power Company, and the Idaho Department of Water Resources, evaluated seasonal seepage gains and losses in selected reaches of the middle Snake River, Idaho, during November 2012 and July 2013, and uncertainty in measured and computed discharge at four Idaho Power Company streamgages. Results from this investigation will be used by resource managers in developing a protocol to calculate and report Adjusted Average Daily Flow at the Idaho Power Company streamgage on the Snake River below Swan Falls Dam, near Murphy, Idaho, which is the measurement point for distributing water to owners of hydropower and minimum flow water rights in the middle Snake River. The evaluated reaches of the Snake River were from King Hill to Murphy, Idaho, for the seepage studies and downstream of Lower Salmon Falls Dam to Murphy, Idaho, for evaluations of discharge uncertainty. Computed seepage was greater than cumulative measurement uncertainty for subreaches along the middle Snake River during November 2012, the non-irrigation season, but not during July 2013, the irrigation season. During the November 2012 seepage study, the subreach between King Hill and C J Strike Dam had a meaningful (greater than cumulative measurement uncertainty) seepage gain of 415 cubic feet per second (ft3/s), and the subreach between Loveridge Bridge and C J Strike Dam had a meaningful seepage gain of 217 ft3/s. The meaningful seepage gain measured in the November 2012 seepage study was expected on the basis of several small seeps and springs present along the subreach, regional groundwater table contour maps, and results of regional groundwater flow model simulations. Computed seepage along the subreach from C J Strike Dam to Murphy was less than cumulative measurement uncertainty during November 2012 and July 2013; therefore, seepage cannot be quantified with certainty along this subreach. For the uncertainty evaluation, average

  9. Comparison of Scour and Flow Characteristics Around Circular and Oblong Bridge Piers in Seepage Affected Alluvial Channels

    Science.gov (United States)

    Chavan, Rutuja; Venkataramana, B.; Acharya, Pratik; Kumar, Bimlesh

    2018-06-01

    The present study examines scour geometry and turbulent flow characteristics around circular and oblong piers in alluvial channel with downward seepage. Experiments were conducted in plane sand bed of non-uniform sand under no seepage, 10% seepage and 15% seepage conditions. Scour depth at oblong pier is significantly lesser than the scour depth at circular one. However, the scour depth at both piers reduces with downward seepage. The measurements show that the velocity and Reynolds stresses are negative near the bed at upstream of piers where the strong reversal occurs. At downstream of oblong pier near the free surface, velocity and Reynolds stresses are less positive; whereas, they are negative at downstream of circular pier. The streamline shape of oblong pier leads to reduce the strength of wake vortices and consequently reversal flow at downstream of pier. With application of downward seepage turbulent kinetic energy is decreasing. The results show that the wake vortices at oblong pier are weaker than the wake vortices at circular pier. The strength of wake vortices diminishes with downward seepage. The Strouhal number is lesser for oblong pier and decreases with downward seepage for both oblong and circular piers.

  10. Evaluating origins and water seepage rates at the subdam A of the Dong Mo reservoir using environmental isotope technique

    International Nuclear Information System (INIS)

    Bui Dac Dung; Trinh Van Giap; Dang Anh Minh; Nguyen Van Hoan

    2008-01-01

    Environmental isotope techniques have been world-widely used for investigating origins and the rates of the seepage - leakage water at reservoir dams. We have conducted a research on the use of environmental isotope techniques for evaluating the origin of the seepage water and the seepage rate at the sub dam A of the Dong Mo reservoir. The main works were collecting water samples, analyzing for 18 O/ 16 O, 2 H(D)/ 1 H ratios, analyzing for 3 H(T) and chemical contents. Findings of the project showed that: a) Waters at the piezometers on the top and the 1st roof are not originated from lake water; b) Waters at the piezometers on 1st and 2nd levels, as well as seepage waters at the dam toe are mixed of lake and ground waters, and the old river bed could be the channel for ground water upcoming from beneath the dam body; c) The transit times of water from the lake to the observation points are from 3 to 4 months, and the seepage velocity is of about 1.1x10 -3 cm/s; d) The findings from tritium analyses show that all waters around the Dong Mo area are recent waters recharged regularly by meteoric water. (author)

  11. Ecologic assessment of closure options for Savannah River Plant waste sites: Task 38, AX-681812

    International Nuclear Information System (INIS)

    1987-01-01

    Ecologic assessment of closure options is one of several analyses being documented in the EIDs (along with analysis of relative potential health risks, accident risks, and costs). This information will serve as a basis for choosing the best option for closing a particular waste facility. This report presents the methodology adopted for SRP waste site ecological assessment, and the results of its application. The results of the ecologic assessment indicated that no impacts are expected for any of the closure options at eleven sites. Significant ecologic impacts are possible at the eight waste sites or groups of waste sites including the Radioactive Waste Burial Grounds, Old TNX Seepage Basin, CMP Pits, F-Area Seepage Basins, H-Area Seepage Basins, SRL Seepage Basins, R-Reactor Seepage Basins, and L-Area Oil and Chemical Basin. 104 refs., 22 figs., 241 tabs

  12. Using self-potential housing technique to model water seepage at the UNHAS housing Antang area

    Science.gov (United States)

    Syahruddin, Muhammad Hamzah

    2017-01-01

    The earth's surface has an electric potential that is known as self-potentiall (SP). One of the causes of the electrical potential at the earth's surface is water seepage into the ground. Electrical potential caused by water velocity seepage into the ground known as streaming potential. How to model water seepage into the ground at the housing Unhas Antang? This study was conducted to answer these questions. The self-potential measurements performed using a simple digital voltmeter Sanwa brand PC500 with a precision of 0.01 mV. While the coordinates of measurements points are self-potential using Global Positioning System. Mmeasurements results thus obtained are plotted using surfer image distribution self-potential housing Unhas Antang. The self-potential data housing Unhas Antang processed by Forward Modeling methods to get a model of water infiltration into the soil. Housing Unhas Antang self-potential has a value of 5 to 23 mV. Self-potential measurements carried out in the rainy season so it can be assumed that the measurement results caused by the velocity water seepage into the ground. The results of modeling the velocity water seepage from the surface to a depth of 3 meters was 2.4 cm/s to 0.2 cm /s. Modeling results showed that the velocity water seepage of the smaller with depth.

  13. Hydrogeologic setting, water budget, and preliminary analysis of ground-water exchange at Lake Starr, a seepage lake in Polk County, Florida

    Science.gov (United States)

    Swancar, Amy; Lee, T.M.; O'Hare, T. M.

    2000-01-01

    Lake Starr, a 134-acre seepage lake of multiple-sinkhole origin on the Lake Wales Ridge of central Florida, was the subject of a detailed water-budget study from August 1996 through July 1998. The study monitored the effects of hydrogeologic setting, climate, and ground-water pumping on the water budget and lake stage. The hydrogeologic setting of the Lake Starr basin differs markedly on the two sides of the lake. Ground water from the surficial aquifer system flows into the lake from the northwest side of the basin, and lake water leaks out to the surficial aquifer system on the southeast side of the basin. Lake Starr and the surrounding surficial aquifer system recharge the underlying Upper Floridan aquifer. The rate of recharge to the Upper Floridan aquifer is determined by the integrity of the intermediate confining unit and by the downward head gradient between the two aquifers. On the inflow side of the lake, the intermediate confining unit is more continuous, allowing ground water from the surficial aquifer system to flow laterally into the lake. Beneath the lake and on the southeast side of the basin, breaches in the intermediate confining unit enhance downward flow to the Upper Floridan aquifer, so that water flows both downward and laterally away from the lake through the ground-water flow system in these areas. An accurate water budget, including evaporation measured by the energy-budget method, was used to calculate net ground-water flow to the lake, and to do a preliminary analysis of the relation of net ground-water fluxes to other variables. Water budgets constructed over different timeframes provided insight on processes that affect ground-water interactions with Lake Starr. Weekly estimates of net ground-water flow provided evidence for the occurrence of transient inflows from the nearshore basin, as well as the short-term effects of head in the Upper Floridan aquifer on ground-water exchange with the lake. Monthly water budgets showed the effects

  14. MN 716: nova cultivar de cevada com estabilidade de produção e qualidade cervejeira Production stability and brewing quality of Barley MN 716

    Directory of Open Access Journals (Sweden)

    Eduardo Caierão

    2006-06-01

    Full Text Available A cevada MN 716, lançada em 2004, é uma das cultivares recomendadas para cultivo com maior estabilidade de produção. Nos anos em que participou do ensaio para determinação de seu valor de cultivo e uso, apresentou excelente produtividade de grãos, com média superior a 3.000 kg ha-1, e desempenho equilibrado quanto à qualidade, com destaque para seu teor de beta-glucanas e índice enzimático. A cultivar constitui um avanço do melhoramento desse cereal no Brasil, aliando características de interesse do produtor e da indústria.Barley cultivar MN 716, released in 2004, is one of the most recomended cultivars, for its high stability. In the years that it was included in the agronomic and use value trial, the cultivar MN 716 showed high yield average, exceeding 3,000 kg ha-1, as well as excellent qualitative performance, mainly in relation to beta-glucans and enzyme index. The cultivar is a breeding achievement for this cereal in Brazil, and serves the interests of both producers and industrial sector.

  15. Numerical Modelling of Tailings Dam Thermal-Seepage Regime Considering Phase Transitions

    Directory of Open Access Journals (Sweden)

    Aniskin Nikolay Alekseevich

    2017-01-01

    Full Text Available Statement of the Problem. The article describes the problem of combined thermal-seepage regime for earth dams and those operated in the permafrost conditions. This problem can be solved using the finite elements method based on the local variational formulation. Results. A thermal-seepage regime numerical model has been developed for the “dam-foundation” system in terms of the tailings dam. The effect of heat-and-mass transfer and liquid phase transition in soil interstices on the dam state is estimated. The study with subsequent consideration of these factors has been undertaken. Conclusions. The results of studying the temperature-filtration conditions of the structure based on the factors of heat-and-mass transfer and liquid phase transition have shown that the calculation results comply with the field data. Ignoring these factors or one of them distorts the real situation of the dam thermal-seepage conditions.

  16. Effects of Atmospheric Dynamics on CO2 Seepage at Mammoth Mountain, California USA

    Directory of Open Access Journals (Sweden)

    Egemen Ogretim

    2013-12-01

    Full Text Available In the past few decades, atmospheric effects on the variation of seepage from soil have been studied in disciplines such as volcanology, environmental protection, safety and health hazard avoidance. Recently, monitoring of potential leakage from the geologic sequestration of carbon has been added to this list. Throughout these diverse fields, barometric pumping and presence of steady winds are the two most commonly investigated atmospheric factors. These two factors have the effect of pumping gas into and out of the unsaturated zone, and sweeping the gas in the porous medium. This study focuses on two new factors related to atmosphere in order to explain the CO2 seepage anomalies observed at the Horseshoe Lake tree kill near Mammoth Mountain, CA, where the temporal variation of seepage due to a storm event could not be explained by the two commonly studied effects. First, the interaction of the lower atmospheric dynamics and the ground topography is considered for its effect on the seepage variation over an area that is linked through high-porosity, high-permeability soils and/or fracture networks. Second, the regional pressure fronts that impose significant pressure oscillation over an area are studied. The comparison of the computer simulation results with the experimental measurements suggests that the seepage anomaly observed at the Horseshoe Lake Tree Kill could be due to the unsteady effects caused by regional pressure fronts.

  17. Shallow bedrock limits groundwater seepage-based headwater climate refugia

    Science.gov (United States)

    Briggs, Martin A.; Lane, John W.; Snyder, Craig D.; White, Eric A.; Johnson, Zachary; Nelms, David L.; Hitt, Nathaniel P.

    2018-01-01

    Groundwater/surface-water exchanges in streams are inexorably linked to adjacent aquifer dynamics. As surface-water temperatures continue to increase with climate warming, refugia created by groundwater connectivity is expected to enable cold water fish species to survive. The shallow alluvial aquifers that source groundwater seepage to headwater streams, however, may also be sensitive to seasonal and long-term air temperature dynamics. Depth to bedrock can directly influence shallow aquifer flow and thermal sensitivity, but is typically ill-defined along the stream corridor in steep mountain catchments. We employ rapid, cost-effective passive seismic measurements to evaluate the variable thickness of the shallow colluvial and alluvial aquifer sediments along a headwater stream supporting cold water-dependent brook trout (Salvelinus fontinalis) in Shenandoah National Park, VA, USA. Using a mean depth to bedrock of 2.6 m, numerical models predicted strong sensitivity of shallow aquifer temperature to the downward propagation of surface heat. The annual temperature dynamics (annual signal amplitude attenuation and phase shift) of potential seepage sourced from the shallow modeled aquifer were compared to several years of paired observed stream and air temperature records. Annual stream water temperature patterns were found to lag local air temperature by ∼8–19 d along the stream corridor, indicating that thermal exchange between the stream and shallow groundwater is spatially variable. Locations with greater annual signal phase lag were also associated with locally increased amplitude attenuation, further suggestion of year-round buffering of channel water temperature by groundwater seepage. Numerical models of shallow groundwater temperature that incorporate regional expected climate warming trends indicate that the summer cooling capacity of this groundwater seepage will be reduced over time, and lower-elevation stream sections may no longer serve as larger

  18. Seepage into drifts in unsaturated fractured rock at Yucca Mountain

    International Nuclear Information System (INIS)

    Birkholzer, Jens; Li, Guomin; Tsang, Chin-Fu; Tsang, Yvonne

    1998-01-01

    An important issue for the long-term performance of underground nuclear waste repository is the rate of seepage into the waste emplacement drifts. A prediction of the future seepage rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, as it is located in thick, partially saturated, fractured tuff formations. The long-term situation in the drifts several thousand years after waste emplacement will be characterized by a relative humidity level close to or equal to 100%, as the drifts will be sealed and unventilated, and the waste packages will have cooled. The underground tunnels will then act as capillary barriers for the unsaturated flow, ideally diverting water around them, if the capillary forces are stronger than gravity and viscous forces. Seepage into the drifts will only be possible if the hydraulic pressure in the rock close to the drift walls increases to positive values; i.e., the flow field becomes locally saturated. In the present work, they have developed and applied a methodology to study the potential rate of seepage into underground cavities embedded in a variably saturated, heterogeneous fractured rock formation. The fractured rock mass is represented as a stochastic continuum where the fracture permeabilities vary by several orders of magnitude. Three different realizations of random fracture permeability fields are generated, with the random permeability structure based on extensive fracture mapping, borehole video analysis, and in-situ air permeability testing. A 3-D numerical model is used to simulate the heterogeneous steady-state flow field around the drift, with the drift geometry explicitly represented within the numerical discretization grid. A variety of flow scenarios are considered assuming present-day and future climate conditions at Yucca Mountain. The numerical study is complemented by theoretical evaluations of the drift seepage problem, using stochastic perturbation theory to develop a better

  19. 36 CFR 71.6 - Golden Age Passport.

    Science.gov (United States)

    2010-07-01

    ... Service headquarters, Washington, D.C., and at field offices designated by the heads of the bureaus... Section 71.6 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR... in front of the Issuing Officer. Passport No _____ Date _____ To the Secretary of the Interior: I do...

  20. The Seepage Simulation of Single Hole and Composite Gas Drainage Based on LB Method

    Science.gov (United States)

    Chen, Yanhao; Zhong, Qiu; Gong, Zhenzhao

    2018-01-01

    Gas drainage is the most effective method to prevent and solve coal mine gas power disasters. It is very important to study the seepage flow law of gas in fissure coal gas. The LB method is a simplified computational model based on micro-scale, especially for the study of seepage problem. Based on fracture seepage mathematical model on the basis of single coal gas drainage, using the LB method during coal gas drainage of gas flow numerical simulation, this paper maps the single-hole drainage gas, symmetric slot and asymmetric slot, the different width of the slot combined drainage area gas flow under working condition of gas cloud of gas pressure, flow path diagram and flow velocity vector diagram, and analyses the influence on gas seepage field under various working conditions, and also discusses effective drainage method of the center hole slot on both sides, and preliminary exploration that is related to the combination of gas drainage has been carried on as well.

  1. solution of confined seepage problems below hydraulic structures

    African Journals Online (AJOL)

    user

    1985-09-01

    Sep 1, 1985 ... boundaries are used for solving the seepage problem beneath practical profiles of ... 1. INTRODUCTION. The study of flow through porous media has a wide range of .... free surface flow [3, 4, 5] and unconfined flow situations ...

  2. Calculation of drift seepage for alternative emplacement designs

    International Nuclear Information System (INIS)

    Li, Guomin; Tsang, Chin-Fu; Birkholzer, Jens

    1999-01-01

    The calculations presented in this report are performed to obtain seepage rates into drift and boreholes for two alternative designs of drift and waste emplacement at Yucca Mountain. The two designs are defined according to the Scope of Work 14012021M1, activity 399621, drafted October 6, 1998, and further refined in a conference telephone call on October 13, 1998, between Mark Balady, Jim Blink, Rob Howard and Chin-Fu Tsang. The 2 designs considered are: (1) Design A--Horizontal boreholes 1.0 m in diameter on both sides of the drift, with each borehole 8 m long and inclined to the drift axis by 30 degrees. The pillar between boreholes, measured parallel to the drift axis, is 3.3 m. In the current calculations, a simplified model of an isolated horizontal borehole 8 m long will be simulated. The horizontal borehole will be located in a heterogeneous fracture continuum representing the repository layer. Three different realizations will be taken from the heterogeneous field, representing three different locations in the rock. Seepage for each realization is calculated as a function of the percolation flux. Design B--Vertical boreholes, 1.0 m in diameter and 8.0 m deep, drilled from the bottom of an excavated 8.0 m diameter drift. Again, the drift with the vertical borehole will be assumed to be located in a heterogeneous fracture continuum, representing the rock at the repository horizon. Two realizations are considered, and seepage is calculated for the 8-m drift with and without the vertical 1-m borehole at its bottom

  3. Natural convection in tunnels at Yucca Mountain and impact on drift seepage

    Energy Technology Data Exchange (ETDEWEB)

    Halecky, N.; Birkholzer, J.T.; Peterson, P.

    2010-04-15

    The decay heat from radioactive waste that is to be disposed in the once proposed geologic repository at Yucca Mountain (YM) will significantly influence the moisture conditions in the fractured rock near emplacement tunnels (drifts). Additionally, large-scale convective cells will form in the open-air drifts and will serve as an important mechanism for the transport of vaporized pore water from the fractured rock in the drift center to the drift end. Such convective processes would also impact drift seepage, as evaporation could reduce the build up of liquid water at the tunnel wall. Characterizing and understanding these liquid water and vapor transport processes is critical for evaluating the performance of the repository, in terms of water-induced canister corrosion and subsequent radionuclide containment. To study such processes, we previously developed and applied an enhanced version of TOUGH2 that solves for natural convection in the drift. We then used the results from this previous study as a time-dependent boundary condition in a high-resolution seepage model, allowing for a computationally efficient means for simulating these processes. The results from the seepage model show that cases with strong natural convection effects are expected to improve the performance of the repository, since smaller relative humidity values, with reduced local seepage, form a more desirable waste package environment.

  4. Laboratorial studies on the seepage impact in open-channel flow turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Herrera Granados, Oscar; Kostecki, Stanislaw, E-mail: Oscar.Herrera-Granados@pwr.wroc.pi [Institute of Geotechnics and Hydro-engineering (I-10), Wroclaw University of Technology. Plac Grunwaldzki 9 D-2 p.112. 50-377 Wroclaw (Poland)

    2011-12-22

    In natural streams, the interaction between water in motion and movable beds derives in transport of material. This is a fact that causes several problems for river regulation, above all in streams which were heavily modified by human interferences. Therefore, to find solutions or at least to alleviate the negative effects that sediment transport can bring with is a topic to be researched. The impact of seepage on river sedimentation processes and open-channel flow is important for environmental issues but it is commonly neglected by water specialists. The present contribution presents the output of a series of experimental works where the influence of seepage on the open channel turbulence is analyzed at the laboratory scale. Even though that the magnitude of the groundwater flow is significantly smaller than the magnitude of the open channel flow; the output of the experiments demonstrates that seepage not only modifies the water-sediment interaction as demonstrated Herrera Granados (2008; 2010); but also is affecting the velocity field and turbulence dynamics of the open-channel flow.

  5. Laboratorial studies on the seepage impact in open-channel flow turbulence

    International Nuclear Information System (INIS)

    Herrera Granados, Oscar; Kostecki, Stanislaw

    2011-01-01

    In natural streams, the interaction between water in motion and movable beds derives in transport of material. This is a fact that causes several problems for river regulation, above all in streams which were heavily modified by human interferences. Therefore, to find solutions or at least to alleviate the negative effects that sediment transport can bring with is a topic to be researched. The impact of seepage on river sedimentation processes and open-channel flow is important for environmental issues but it is commonly neglected by water specialists. The present contribution presents the output of a series of experimental works where the influence of seepage on the open channel turbulence is analyzed at the laboratory scale. Even though that the magnitude of the groundwater flow is significantly smaller than the magnitude of the open channel flow; the output of the experiments demonstrates that seepage not only modifies the water-sediment interaction as demonstrated Herrera Granados (2008; 2010); but also is affecting the velocity field and turbulence dynamics of the open-channel flow.

  6. Fault zone controlled seafloor methane seepage in the rupture area of the 2010 Maule Earthquake, Central Chile

    OpenAIRE

    Geersen, Jacob; Scholz, Florian; Linke, Peter; Schmidt, Mark; Lange, Dietrich; Behrmann, Jan H.; Völker, David; Hensen, Christian

    2016-01-01

    Seafloor seepage of hydrocarbon-bearing fluids has been identified in a number of marine forearcs. However, temporal variations in seep activity and the structural and tectonic parameters that control the seepage often remain poorly constrained. Subduction-zone earthquakes for example, are often discussed to trigger seafloor seepage but causal links that go beyond theoretical considerations have not yet been fully established. This is mainly due to the inaccessibility of offshore epicentral a...

  7. A pragmatic method for estimating seepage losses for small reservoirs with application in rural India

    Science.gov (United States)

    Oblinger, Jennifer A.; Moysey, Stephen M. J.; Ravindrinath, Rangoori; Guha, Chiranjit

    2010-05-01

    SummaryThe informal construction of small dams to capture runoff and artificially recharge ground water is a widespread strategy for dealing with water scarcity. A lack of technical capacity for the formal characterization of these systems, however, is often an impediment to the implementation of effective watershed management practices. Monitoring changes in reservoir storage provides a conceptually simple approach to quantify seepage, but does not account for the losses occurring when seepage is balanced by inflows to the reservoir and the stage remains approximately constant. To overcome this problem we evaluate whether a physically-based volume balance model that explicitly represents watershed processes, including reservoir inflows, can be constrained by a limited set of data readily collected by non-experts, specifically records of reservoir stage, rainfall, and evaporation. To assess the impact of parameter non-uniqueness associated with the calibration of the non-linear model, we perform a Monte Carlo analysis to quantify uncertainty in the total volume of water contributed to the subsurface by the 2007 monsoon for a dam located in the Deccan basalts near the village of Salri in Madhya Pradesh, India. The Monte Carlo analysis demonstrated that subsurface losses from the reservoir could be constrained with the available data, but additional measurements are required to constrain reservoir inflows. Our estimate of seepage from the reservoir (7.0 ± 0.6 × 10 4 m 3) is 3.5 times greater than the recharge volume estimated by considering reservoir volume changes alone. This result suggests that artificial recharge could be significantly underestimated when reservoir inflows are not explicitly included in models. Our seepage estimate also accounts for about 11% of rainfall occurring upstream of the dam and is comparable in magnitude to natural ground water recharge, thereby indicating that the reservoir plays a significant role in the hydrology of this small

  8. R-Area Reactor 1993 annual groundwater monitoring report

    International Nuclear Information System (INIS)

    1994-09-01

    Groundwater was sampled and analyzed during 1993 from wells monitoring the following locations in R Area: Well cluster P20 east of R Area (one well each in the water table and the McBean formation), the R-Area Acid/Caustic Basin (the four water-table wells of the RAC series), the R-Area Ash Basin/Coal Pile (one well of the RCP series in the Congaree formation and one in the water table), the R-Area Disassembly Basin (the three water-table wells of the RDB series), the R-Area Burning/Rubble Pits (the four water-table wells of the RRP series), and the R-Area Seepage Basins (numerous water-table wells in the RSA, RSB, RSC, RSD, RSE, and RSF series). Lead was the only constituent detected above its 50μg/L standard in any but the seepage basin wells; it exceeded that level in one B well and in 23 of the seepage basin wells. Cadmium exceeded its drinking water standard (DWS) in 30 of the seepage basin wells, as did mercury in 10. Nitrate-nitrite was above DWS once each in two seepage basin wells. Tritium was above DWS in six seepage basin wells, as was gross alpha activity in 22. Nonvolatile beta exceeded its screening standard in 29 wells. Extensive radionuclide analyses were requested during 1993 for the RCP series and most of the seepage basin wells. Strontium-90 in eight wells was the only specific radionuclide other than tritium detected above DWS; it appeared about one-half of the nonvolatile beta activity in those wells

  9. Determining the REV for Fracture Rock Mass Based on Seepage Theory

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    2017-01-01

    Full Text Available Seepage problems of the fractured rock mass have always been a heated topic within hydrogeology and engineering geology. The equivalent porous medium model method is the main method in the study of the seepage of the fractured rock mass and its engineering application. The key to the method is to determine a representative elementary volume (REV. The FractureToKarst software, that is, discrete element software, is a main analysis tool in this paper and developed by a number of authors. According to the standard of rock classification established by ISRM, this paper aims to discuss the existence and the size of REV of fractured rock masses with medium tractility and provide a general method to determine the existence of REV. It can be gleaned from the study that the existence condition of fractured rock mass with medium tractility features average fracture spacing smaller than 0.6 m. If average fracture spacing is larger than 0.6 m, there is no existence of REV. The rationality of the model is verified by a case study. The present research provides a method for the simulation of seepage field in fissured rocks.

  10. Temporal variability of exchange between groundwater and surface water based on high-frequency direct measurements of seepage at the sediment-water interface

    Science.gov (United States)

    Rosenberry, Donald O.; Sheibley, Rich W.; Cox, Stephen E.; Simonds, Frederic W.; Naftz, David L.

    2013-01-01

    Seepage at the sediment-water interface in several lakes, a large river, and an estuary exhibits substantial temporal variability when measured with temporal resolution of 1 min or less. Already substantial seepage rates changed by 7% and 16% in response to relatively small rain events at two lakes in the northeastern USA, but did not change in response to two larger rain events at a lake in Minnesota. However, seepage at that same Minnesota lake changed by 10% each day in response to withdrawals from evapotranspiration. Seepage increased by more than an order of magnitude when a seiche occurred in the Great Salt Lake, Utah. Near the head of a fjord in Puget Sound, Washington, seepage in the intertidal zone varied greatly from −115 to +217 cm d−1 in response to advancing and retreating tides when the time-averaged seepage was upward at +43 cm d−1. At all locations, seepage variability increased by one to several orders of magnitude in response to wind and associated waves. Net seepage remained unchanged by wind unless wind also induced a lake seiche. These examples from sites distributed across a broad geographic region indicate that temporal variability in seepage in response to common hydrological events is much larger than previously realized. At most locations, seepage responded within minutes to changes in surface-water stage and within minutes to hours to groundwater recharge associated with rainfall. Likely implications of this dynamism include effects on water residence time, geochemical transformations, and ecological conditions at and near the sediment-water interface.

  11. Analysis of three-dimensional transient seepage into ditch drains ...

    Indian Academy of Sciences (India)

    Ratan Sarmah

    waterlogged soils in many regions of the world, including. India [2, 6–9]—to name a ... predicting two-dimensional seepage into a network of ...... when d1 ¼ 0, the lower limits of integration of the integral ...... and agricultural development. Irrig.

  12. The analysis of physicochemical characteristics of pig farm seepage ...

    African Journals Online (AJOL)

    Dikonketso Matjuda

    -bodies, promoting ... that the seepage from pig farm degraded the natural environment by causing eutrophication, promote ... mainly livestock droppings, heavy metals, fertilizers and ... from microorganisms to insects, birds, fish, and at the.

  13. A Pore Scale Flow Simulation of Reconstructed Model Based on the Micro Seepage Experiment

    Directory of Open Access Journals (Sweden)

    Jianjun Liu

    2017-01-01

    Full Text Available Researches on microscopic seepage mechanism and fine description of reservoir pore structure play an important role in effective development of low and ultralow permeability reservoir. The typical micro pore structure model was established by two ways of the conventional model reconstruction method and the built-in graphics function method of Comsol® in this paper. A pore scale flow simulation was conducted on the reconstructed model established by two different ways using creeping flow interface and Brinkman equation interface, respectively. The results showed that the simulation of the two models agreed well in the distribution of velocity, pressure, Reynolds number, and so on. And it verified the feasibility of the direct reconstruction method from graphic file to geometric model, which provided a new way for diversifying the numerical study of micro seepage mechanism.

  14. Numerical experiments on the probability of seepage into underground openings in heterogeneous fractured rock

    International Nuclear Information System (INIS)

    Birkholzer, J.; Li, G.; Tsang, C.F.; Tsang, Y.

    1998-01-01

    An important issue for the performance of underground nuclear waste repositories is the rate of seepage into the waste emplacement drifts. A prediction of this rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, because it is located in thick, unsaturated, fractured tuff formations. Underground opening in unsaturated media might act as capillary barriers, diverting water around them. In the present work, they study the potential rate of seepage into drifts as a function of the percolation flux at Yucca Mountain, based on a stochastic model of the fractured rock mass in the drift vicinity. A variety of flow scenarios are considered, assuming present-day and possible future climate conditions. They show that the heterogeneity in the flow domain is a key factor controlling seepage rates, since it causes channelized flow and local ponding in the unsaturated flow field

  15. Pond-aquifer flow and water availability in the vicinity of two coastal area seepage ponds, Glynn and Bulloch Counties, Georgia

    Science.gov (United States)

    Clarke, John S.; Rumman, Malek Abu

    2005-01-01

    Pond-aquifer flow and water availability at excavated seepage pond sites in Glynn County and in southern Bulloch County, Georgia, were evaluated to determine their potential as sources of water supply for irrigation. Excavated seepage ponds derive water primarily from ground water seeping into the pond, in a manner similar to a dug well completed in a surficial aquifer. The availability of water from seepage ponds is controlled by the permeability of surficial deposits, the amount of precipitation recharging the ground-water system, and the volume of water stored in the pond. The viability of seepage ponds as supplies for irrigation is limited by low seepage rates and high dependence on climatic conditions. Ponds will not refill unless there is adequate precipitation to recharge the surficial aquifer, which subsequently drains (seeps) into the pond. Ground-water seepage was estimated using a water-budget approach that utilized on-site climatic and hydrologic measurements, computing pond-volume changes during pond pumping tests, and by digital simulation using steady-state and transient ground-water flow models. From August 1999 to May 2000, the Glynn County pond was mostly losing water (as indicated by negative net seepage); whereas from October 2000 to June 2001, the Bulloch County pond was mostly gaining water. At both sites, most ground-water seepage entered the pond following major rainfall events that provided recharge to the surficial aquifer. Net ground-water seepage, estimated using water-budget analysis and simulation, ranged from -11.5 to 15 gallons per minute (gal/min) at the Glynn County pond site and from -55 to 31 gal/min at the Bulloch County pond site. Simulated values during pumping tests indicate that groundwater seepage to both ponds increases with decreased pond stage. At the Glynn County pond, simulated net ground-water seepage varied between 7.8 gal/min at the beginning of the test (high pond stage and low hydraulic gradient) and 103 gal

  16. Decontamination and decommissioning of the SPERT-I seepage pit at the Idaho National Engineering Laboratory. Final report

    International Nuclear Information System (INIS)

    Suckel, R.A.

    1984-11-01

    This report describes the decontamination and decommissioning of the SPERT-I seepage pit. Prior to its decontamination and decommissioning, the seepage pit was surrounded by an earthen dike varying from 2 to 6 ft above the pit bottom. A 6-in., cast iron, underground waste line originated at the pit tank in the reactor building and ran approximately 68 ft to the seepage pit. The soil in the seepage pit contained low-level radioactive contamination. The soil surface was removed to a depth of 2.5 ft and shipped to the Radioactive Waste Management Complex (RWMC). The waste line that contained fixed contamination was removed and also sent to the RWMC. The pit was backfilled with radiologically clean soil, reducing the surface activity to background. A permanent marker was erected over the backfilled pit to indicate that presence of residual subsurface radioactive contamination. 5 references, 26 figures, 3 tables

  17. On leakage and seepage from geological carbon sequestration sites

    Energy Technology Data Exchange (ETDEWEB)

    Oldenburg, C.M.; Unger, A.J.A.; Hepple, R.P.; Jordan, P.D.

    2002-07-18

    Geologic carbon sequestration is one strategy for reducing the rate of increase of global atmospheric carbon dioxide (CO{sub 2} ) concentrations (IEA, 1997; Reichle, 2000). As used here, the term geologic carbon sequestration refers to the direct injection of supercritical CO{sub 2} deep into subsurface target formations. These target formations will typically be either depleted oil and gas reservoirs, or brine-filled permeable formations referred to here as brine formations. Injected CO{sub 2} will tend to be trapped by one or more of the following mechanisms: (1) permeability trapping, for example when buoyant supercritical CO{sub 2} rises until trapped by a confining caprock; (2) solubility trapping, for example when CO{sub 2} dissolves into the aqueous phase in water-saturated formations, or (3) mineralogic trapping, such as occurs when CO{sub 2} reacts to produce stable carbonate minerals. When CO{sub 2} is trapped in the subsurface by any of these mechanisms, it is effectively sequestered away from the atmosphere where it would otherwise act as a greenhouse gas. The purpose of this report is to summarize our work aimed at quantifying potential CO{sub 2} seepage due to leakage from geologic carbon sequestration sites. The approach we take is to present first the relevant properties of CO{sub 2} over the range of conditions from the deep subsurface to the vadose zone (Section 2), and then discuss conceptual models for how leakage might occur (Section 3). The discussion includes consideration of gas reservoir and natural gas storage analogs, along with some simple estimates of seepage based on assumed leakage rates. The conceptual model discussion provides the background for the modeling approach wherein we focus on simulating transport in the vadose zone, the last potential barrier to CO{sub 2} seepage (Section 4). Because of the potentially wide range of possible properties of actual future geologic sequestration sites, we carry out sensitivity analyses by

  18. modelingthe effect the effect of contact and seepage forces

    African Journals Online (AJOL)

    eobe

    This research work has investigated the contribution of contact force and seepage force to the ... e equilibrium model has deduced an expression for the safe hydraulic head during well ...... Plastic deformation of soils simulation using DEM,.

  19. Fiber Bragg grating-based performance monitoring of a slope model subjected to seepage

    Science.gov (United States)

    Zhu, Hong-Hu; Shi, Bin; Yan, Jun-Fan; Zhang, Jie; Zhang, Cheng-Cheng; Wang, Bao-Jun

    2014-09-01

    In the past few years, fiber optic sensing technologies have played an increasingly important role in the health monitoring of civil infrastructures. These innovative sensing technologies have recently been successfully applied to the performance monitoring of a series of geotechnical structures. Fiber optic sensors have shown many unique advantages in comparison with conventional sensors, including immunity to electrical noise, higher precision and improved durability and embedding capabilities; fiber optic sensors are also smaller in size and lighter in weight. In order to explore the mechanism of seepage-induced slope instability, a small-scale 1 g model test of the soil slope has been performed in the laboratory. During the model’s construction, specially fabricated sensing fibers containing nine fiber Bragg grating (FBG) strain sensors connected in a series were horizontally and vertically embedded into the soil mass. The surcharge load was applied on the slope crest, and the groundwater level inside of the slope was subsequently varied using two water chambers installed besides the slope model. The fiber optic sensing data of the vertical and horizontal strains within the slope model were automatically recorded by an FBG interrogator and a computer during the test. The test results are presented and interpreted in detail. It is found that the gradually accumulated deformation of the slope model subjected to seepage can be accurately captured by the quasi-distributed FBG strain sensors. The test results also demonstrate that the slope stability is significantly affected by ground water seepage, which fits well with the results that were calculated using finite element and limit equilibrium methods. The relationship between the strain measurements and the safety factors is further analyzed, together with a discussion on the residual strains. The performance evaluation of a soil slope using fiber optic strain sensors is proved to be a potentially effective

  20. Fiber Bragg grating-based performance monitoring of a slope model subjected to seepage

    International Nuclear Information System (INIS)

    Zhu, Hong-Hu; Shi, Bin; Yan, Jun-Fan; Zhang, Cheng-Cheng; Wang, Bao-Jun; Zhang, Jie

    2014-01-01

    In the past few years, fiber optic sensing technologies have played an increasingly important role in the health monitoring of civil infrastructures. These innovative sensing technologies have recently been successfully applied to the performance monitoring of a series of geotechnical structures. Fiber optic sensors have shown many unique advantages in comparison with conventional sensors, including immunity to electrical noise, higher precision and improved durability and embedding capabilities; fiber optic sensors are also smaller in size and lighter in weight. In order to explore the mechanism of seepage-induced slope instability, a small-scale 1 g model test of the soil slope has been performed in the laboratory. During the model’s construction, specially fabricated sensing fibers containing nine fiber Bragg grating (FBG) strain sensors connected in a series were horizontally and vertically embedded into the soil mass. The surcharge load was applied on the slope crest, and the groundwater level inside of the slope was subsequently varied using two water chambers installed besides the slope model. The fiber optic sensing data of the vertical and horizontal strains within the slope model were automatically recorded by an FBG interrogator and a computer during the test. The test results are presented and interpreted in detail. It is found that the gradually accumulated deformation of the slope model subjected to seepage can be accurately captured by the quasi-distributed FBG strain sensors. The test results also demonstrate that the slope stability is significantly affected by ground water seepage, which fits well with the results that were calculated using finite element and limit equilibrium methods. The relationship between the strain measurements and the safety factors is further analyzed, together with a discussion on the residual strains. The performance evaluation of a soil slope using fiber optic strain sensors is proved to be a potentially effective

  1. Three Dimensional Seepage Analyses in Mollasadra Dam after Its ...

    African Journals Online (AJOL)

    Michael Horsfall

    constructed on Kor River. pore water pressure in the dam was investigated following its construction and first and second ... Some problems like seepage failure and slope stability are ... In addition, the effects of change in certain input ...

  2. Numerical simulations of seepage flow in rough single rock fractures

    Directory of Open Access Journals (Sweden)

    Qingang Zhang

    2015-09-01

    Full Text Available To investigate the relationship between the structural characteristics and seepage flow behavior of rough single rock fractures, a set of single fracture physical models were produced using the Weierstrass–Mandelbrot functions to test the seepage flow performance. Six single fractures, with various surface roughnesses characterized by fractal dimensions, were built using COMSOL multiphysics software. The fluid flow behavior through the rough fractures and the influences of the rough surfaces on the fluid flow behavior was then monitored. The numerical simulation indicates that there is a linear relationship between the average flow velocity over the entire flow path and the fractal dimension of the rough surface. It is shown that there is good a agreement between the numerical results and the experimental data in terms of the properties of the fluid flowing through the rough single rock fractures.

  3. Formation of Box Canyon, Idaho, by megaflood: implications for seepage erosion on Earth and Mars.

    Science.gov (United States)

    Lamb, Michael P; Dietrich, William E; Aciego, Sarah M; Depaolo, Donald J; Manga, Michael

    2008-05-23

    Amphitheater-headed canyons have been used as diagnostic indicators of erosion by groundwater seepage, which has important implications for landscape evolution on Earth and astrobiology on Mars. Of perhaps any canyon studied, Box Canyon, Idaho, most strongly meets the proposed morphologic criteria for groundwater sapping because it is incised into a basaltic plain with no drainage network upstream, and approximately 10 cubic meters per second of seepage emanates from its vertical headwall. However, sediment transport constraints, 4He and 14C dates, plunge pools, and scoured rock indicate that a megaflood (greater than 220 cubic meters per second) carved the canyon about 45,000 years ago. These results add to a growing recognition of Quaternary catastrophic flooding in the American northwest, and may imply that similar features on Mars also formed by floods rather than seepage erosion.

  4. Geochemical characterisation of seepage and drainage water quality from two sulphide mine tailings impoundments: Acid mine drainage versus neutral mine drainage

    Science.gov (United States)

    Heikkinen, P.M.; Raisanen, M.L.; Johnson, R.H.

    2009-01-01

    Seepage water and drainage water geochemistry (pH, EC, O2, redox, alkalinity, dissolved cations and trace metals, major anions, total element concentrations) were studied at two active sulphide mine tailings impoundments in Finland (the Hitura Ni mine and Luikonlahti Cu mine/talc processing plant). The data were used to assess the factors influencing tailings seepage quality and to identify constraints for water treatment. Changes in seepage water quality after equilibration with atmospheric conditions were evaluated based on geochemical modelling. At Luikonlahti, annual and seasonal changes were also studied. Seepage quality was largely influenced by the tailings mineralogy, and the serpentine-rich, low sulphide Hitura tailings produced neutral mine drainage with high Ni. In contrast, drainage from the high sulphide, multi-metal tailings of Luikonlahti represented typical acid mine drainage with elevated contents of Zn, Ni, Cu, and Co. Other factors affecting the seepage quality included weathering of the tailings along the seepage flow path, process water input, local hydrological settings, and structural changes in the tailings impoundment. Geochemical modelling showed that pH increased and some heavy metals were adsorbed to Fe precipitates after net alkaline waters equilibrated with the atmosphere. In the net acidic waters, pH decreased and no adsorption occurred. A combination of aerobic and anaerobic treatments is proposed for Hitura seepages to decrease the sulphate and metal loading. For Luikonlahti, prolonged monitoring of the seepage quality is suggested instead of treatment, since the water quality is still adjusting to recent modifications to the tailings impoundment.

  5. Modeling of Seepage Losses in Sewage Sludge Drying Bed ...

    African Journals Online (AJOL)

    This research was carried out to develop a model governing seepage losses in sewage sludge drying bed. The model will assist in the design of sludge drying beds for effective management of wastes derived from households' septic systems. In the experiment conducted this study, 125kg of sewage sludge, 90.7% moisture ...

  6. Variation of stream power with seepage in sand-bed channels

    African Journals Online (AJOL)

    2009-12-27

    Dec 27, 2009 ... Keywords: friction slope, seepage, sediment transport, stream power, suction ... particles from the bed and on further movement of the bed load is of great ..... KNIGHTON AD (1987) River channel adjustment – the down stream.

  7. Mud extrusion and ring-fault gas seepage - upward branching fluid discharge at a deep-sea mud volcano.

    Science.gov (United States)

    Loher, M; Pape, T; Marcon, Y; Römer, M; Wintersteller, P; Praeg, D; Torres, M; Sahling, H; Bohrmann, G

    2018-04-19

    Submarine mud volcanoes release sediments and gas-rich fluids at the seafloor via deeply-rooted plumbing systems that remain poorly understood. Here the functioning of Venere mud volcano, on the Calabrian accretionary prism in ~1,600 m water depth is investigated, based on multi-parameter hydroacoustic and visual seafloor data obtained using ship-borne methods, ROVs, and AUVs. Two seepage domains are recognized: mud breccia extrusion from a summit, and hydrocarbon venting from peripheral sites, hosting chemosynthetic ecosystems and authigenic carbonates indicative of long-term seepage. Pore fluids in freshly extruded mud breccia (up to 13 °C warmer than background sediments) contained methane concentrations exceeding saturation by 2.7 times and chloride concentrations up to five times lower than ambient seawater. Gas analyses indicate an underlying thermogenic hydrocarbon source with potential admixture of microbial methane during migration along ring faults to the peripheral sites. The gas and pore water analyses point to fluids sourced deep (>3 km) below Venere mud volcano. An upward-branching plumbing system is proposed to account for co-existing mud breccia extrusion and gas seepage via multiple surface vents that influence the distribution of seafloor ecosystems. This model of mud volcanism implies that methane-rich fluids may be released during prolonged phases of moderate activity.

  8. Effects of Loading Rate on Gas Seepage and Temperature in Coal and Its Potential for Coal-Gas Disaster Early-Warning

    Directory of Open Access Journals (Sweden)

    Chong Zhang

    2017-08-01

    Full Text Available The seepage velocity and temperature externally manifest the changing structure, gas desorption and energy release that occurs in coal containing gas failure under loading. By using the system of coal containing gas failure under loading, this paper studies the law of seepage velocity and temperature under different loading rates and at 1.0 MPa confining pressure and 0.5 MPa gas pressure, and combined the on-site results of gas pressure and temperature. The results show that the stress directly affects the seepage velocity and temperature of coal containing gas, and the pressure and content of gas have the most sensitivity to mining stress. Although the temperature is not sensitive to mining stress, it has great correlation with mining stress. Seepage velocity has the characteristic of critically slowing down under loading. This is demonstrated by the variance increasing before the main failure of the samples. Therefore, the variance of seepage velocity with time and temperature can provide an early warning for coal containing gas failing and gas disasters in a coal mine.

  9. Physics Letters B, Volume 716, Issue 1- Cover Page

    CERN Multimedia

    CERN

    2012-01-01

    The cover page of the Physics Letters B Journal, Volume 716, Issue 1, dedicated to the observation of a new particle in the search for the Standard Model Higgs boson. To celebrate this historical discovery, Elsevier reprinted the ATLAS and the CMS articles together with a foreword by Peter Higgs and the other scientists that predicted the existence of the so-called Higgs boson and published this in a separate booklet.

  10. Investigation of seepage around the bucket skirt during installation in sand

    DEFF Research Database (Denmark)

    Koteras, Aleksandra Katarzyna; Ibsen, Lars Bo

    or along bucket skirt with known soil condition, bucket geometry and applied suction. The second aim of the study is to evaluate expressions for normalized seepage length, s/h, for different soil combinations and penetration depths. The seepage length is then 7 used to make a prediction of critical...... pressure that will create piping channels at exit, which is near to seabed and to the caisson wall, along bucket wall and at the tip. That is how the limits for suction installation can be assumed. Finally, the critical suction is used for predicting the reduction of penetration resistance and the method...... describing this approach is presented in the report with its assumptions. The method is called AAU CPT-based method and it is a great step in the development of practical design tool for bucket foundation installation process....

  11. 12 CFR 716.6 - Information to be included in privacy notices.

    Science.gov (United States)

    2010-01-01

    ...) Financial service providers; (ii) Non-financial companies; and (iii) Others. (4) Disclosures under exception... CREDIT UNIONS PRIVACY OF CONSUMER FINANCIAL INFORMATION Privacy and Opt Out Notices § 716.6 Information... jointly with another financial institution, you satisfy the disclosure requirement of paragraph (a)(5) of...

  12. Design philosophy and practice of asymmetrical 3D fracturing and random fracturing: A case study of tight sand gas reservoirs in western Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Jianchun Guo

    2015-03-01

    Full Text Available At present two technical models are commonly taken in tight gas reservoir stimulation: conventional massive fracturing and SRV fracturing, but how to select a suitable fracturing model suitable for reservoir characteristics is still a question waiting to be answered. In this paper, based on the analysis of geological characteristics and seepage mechanism of tight gas and shale gas reservoirs, the differences between stimulation philosophy of tight gas reservoirs and shale reservoirs are elucidated, and the concept that a suitable stimulation model should be selected based on reservoir geological characteristics and seepage mechanism aiming at maximally improving the seepage capability of a reservoir. Based on this concept, two fracturing design methods were proposed for two tight gas reservoirs in western Sichuan Basin: asymmetrical 3D fracturing design (A3DF for the middle-shallow Upper Jurassic Penglaizhen Fm stacked reservoirs in which the hydraulic fractures can well match the sand spatial distribution and seepage capability of the reservoirs; SRV fracturing design which can increase fracture randomness in the sandstone and shale laminated reservoirs for the 5th Member of middle-deep Upper Triassic Xujiahe Fm. Compared with that by conventional fracturing, the average production of horizontal wells fractured by A3DF increased by 41%, indicating that A3DF is appropriate for gas reservoir development in the Penglaizhen Fm; meanwhile, the average production per well of the 5th Member of the Xujiahe Fm was 2.25 × 104 m3/d after SRV fracturing, showing that the SRV fracturing is a robust technical means for the development of this reservoir.

  13. Contribution to atmospheric methane by natural seepages on the Bulgarian continental shelf

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrov, L. [Bulgarian Academy of Science, Varna (Bulgaria). Inst. of Oceanology

    2002-07-01

    This paper provides an estimation of the atmospheric methane flux from Bulgarian Black Sea continental shelf. Potential gas source rocks include Holocene gas-charged sediments, Quaternary peats and sapropels, and deep-lying Palaeocene and Neogene clays, Cretaceous coals, and other sediments of late Jurassic to early Cretaceous age. These cover almost the whole continental shelf and slope and, together with irregularly developed seal rocks and widespread active and conducting faults, provide good conditions for upward gas migration. A total of 5 100 line kilometers of shallow seismic (boomer) and echo-sounder records acquired during the Institute of Oceanology's regional surveys, and several detailed side-scan sonar lines, have been reviewed for water column targets. Four hundred and eighty-two targets were assigned as gas seepage plumes. It is estimated that a total of 19,735 individual seeps exists on the open shelf. The number of seeps in coastal waters was estimated to be 6020; this is based on available public-domain data, specific research, and results of a specially made questionnaire which was distributed to a range of 'seamen'. More than 150 measurements of the seabed flux rates were made in the 'Golden sands' and 'Zelenka' seepage areas between 1976 and 1991. Indirect estimations of flux rates from video and photo materials, and a review of published data have also been undertaken. Based on these data, three types of seepages were identified as the most representative of Bulgarian coastal waters. These have flux rates of 0.4, 1.8, and 3.51/min. The contribution to atmospheric methane is calculated by multiplying the flux rates with the number of seepages, and entering corrections for methane concentration and the survival of gas bubbles as they ascend through seawater of the corresponding water depth. The estimation indicates that between 45,100,000 (0.03 Tg) and 210,650,000 m{sup 3} (0. 15 Tg) methane yr{sup -1} come

  14. Groundwater flow and heterogeneous discharge into a seepage lake

    DEFF Research Database (Denmark)

    Kazmierczak, Jolanta; Müller, Sascha; Nilsson, B.

    2016-01-01

    with the lake remained under seemingly steady state conditions across seasons, a high spatial and temporal heterogeneity in the discharge to the lake was observed. The results showed that part of the groundwater flowing from the west passes beneath the lake and discharges at the eastern shore, where groundwater......Groundwater discharge into a seepage lake was investigated by combining flux measurements, hydrochemical tracers, geological information, and a telescopic modeling approach using first two-dimensional (2-D) regional then 2-D local flow and flow path models. Discharge measurements and hydrochemical...... tracers supplement each other. Discharge measurements yield flux estimates but rarely provide information about the origin and flow path of the water. Hydrochemical tracers may reveal the origin and flow path of the water but rarely provide any information about the flux. While aquifer interacting...

  15. Simulation of water seepage through a vadose zone in fractured rock

    International Nuclear Information System (INIS)

    Fuentes, Nestor O.

    2003-01-01

    In order to improve our understanding of the vadose zone in fractured rock, obtaining useful tools to simulate, predict and prevent subsurface contamination, a three-dimensional model has been developed from the base of recent two-dimensional codes. Fracture systems are simulated by means of a dynamical evolution of a random-fuse network model, and the multiphase expression of Richards equation is used to describe fluid displacements. Physical situations presented here emphasized the importance of fracture connectivity and spatial variability on the seepage evolution through the vadose zone, and confirm the existence of dendritic patterns along localized preferential paths. (author)

  16. Tracing the source of emerging seepage water at failure slope downstream, Kampung Bharu Bukit Tinggi, Bentong, Pahang

    International Nuclear Information System (INIS)

    Lakam Mejus; Wan Zakaria Wan Mohd Tahir; Md Shahid Ayub; Jeremy Andy; Johari Latif

    2006-01-01

    This paper discusses method and monitoring result of the source of seepage water emerging (mud flow) at downstream toe of the failure slope at Kampung Bharu Bukit Tinggi, Bentong Pahang. In this investigation, a saline-tracer experiment was conducted by injecting its solution into a drain at an upstream section (old road to Janda Baik town) where a pipeline was found leaking in the vicinity of the roadside and flowing towards hill slopes. Some parts of flowing water was left undetected and seeped through the soil on its way to downstream area. Seepage water downstream was monitored by using a conductivity sensor hooked up to a CR10X data logger and optical back scattering conductivity probes. From the result, it is believed that the source of seepage water is related to the water from the leaking pipeline upstream. The travelling time for the leaking water to reach downstream slope failure was within 16-17 hours. Based on this preliminary investigation, one can conclude that seepage water is one of the main contributing factors that cause slope failure in the vicinity of the investigated hill slopes. Further investigation to understand the failure mechanism at this place by conducting multi-experimental approaches in different seasons, particularly during continuous rain storms. (Author)

  17. 77 FR 16215 - Commission Information Collection Activities (FERC-716); Comment Request

    Science.gov (United States)

    2012-03-20

    ...: Title: FERC-716, Good Faith Request for Transmission Service and Response by Transmitting Utility Under... valid good faith request for transmission has been made under section 211 of the FPA. By developing the.... As a result, 18 CFR 2.20 identifies 12 components of a good faith estimate and 5 components of a...

  18. Heterogeneous Seepage at the Nopal I Uranium Mine, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Dobson, Patrick; Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat; Rodriguez, J. Alfredo; Garza, Rodrigo de la

    2008-01-01

    The primary objective of this analogue study is to evaluate flow and transport processes of relevance to the proposed Yucca Mountain repository. Seepage data obtained from this study will be used to constrain flow and transport models being developed for the Nopal I system

  19. Forward modeling of seepage of reservoir dam based on ground penetrating radar

    Directory of Open Access Journals (Sweden)

    Xueli WU

    2017-08-01

    Full Text Available The risk of the reservoir dam seepage will bring the waste of water resources and the loss of life and property. The ground penetrating radar (GPR is designed as a daily inspection system of dams to improve the existing technology which can't determine the actual situation of the dam seepage tunnel coordinates. The finite difference time domain (FDTD is used to solve the Yee's grids discreatization in two-dimensional space, and its electromagnetic distribution equation is obtained as well. Based on the actual structure of reservoir dam foundation, the ideal model of air layer, concrete layer, clay layer and two water seepage holes is described in detail, and the concrete layer interference model with limestone interference point is established. The system architecture is implemented by using MATLAB, and the forward modeling is performed. The results indicate that ground penetrating radar can be used for deep target detection. Through comparing the detection spectrum of three kinds of frequency electromagnetic wave by changing the center frequency of the GPR electromagnetic wave of 50 MHz, 100 MHz and 200 MHz, it is concluded that the scanning result is more accurate at 100 MHz. At the same time, the simulation results of the interference model show that this method can be used for the detection of complex terrain.

  20. Seepage investigation by using Isotope and Geophysical Techniques in Gumti Flood Embankment/Dyke, Comilla

    International Nuclear Information System (INIS)

    Ahmed, N.; Wallin, B. G.; Majumder, R. K.; Mikail, M.; Rahman, M. S.

    2004-06-01

    Gumti Flood Control Embankment/Dyke is vital for irrigation water supply and flood control. Water seepage/leakage and slope failures are the major issues in Gumti earthen dyke. The distinct seepage and slope failure zone were observed at three places (Farizpur, Kathalia and Ebdarpur) along the countryside of left dyke. The isotopic technique has been integrated in the conventional hydrologic investigations. The isotope methodology works essentially by developing a characteristics pattern of the isotopic composition to identify the sources and flow dynamics of seeping/leaking in the dykes. Two sampling campaigns were conducted; one was on October, 2002 and the other was on July, 2003; near the seepage/leakage site for chemical analysis and stable isotopic analysis (''2H and ''1 8 O). Both samplings were done after recession of peak water level in the Gumti river. Interpretation of the hydrochemical data implies that the groundwater near the investigated seepage zones is Na-Ca-HCO 3 type and the river water is Ca-Mg-HCO 3 type. The chlorides content of both groundwater and river water are found mostly similar, indicating mixing between the two water system. The stable isotopes (''2H and ''1 8 O) of groundwater fall on the Meteoric Water Line, ranging the oxygen-18 values from -4.98 to -5.46 per mil and deuterium values from -30.0 to -33.6 per mil. It indicates the recharge from the river water during peak water level in the river Gumti. On the other hand, the stable isotopes of the Gumti river show some evaporation effect, which might have occurred due to stagnation of flowing water in the river. The oxygen-18 and deuterium values for river water range from -3.61 to -4.43 per mil and from -22.30 to -28.48 per mil respectively. These isotope results reflect the hydraulic connectivity between the river water and groundwater through the base of dyke. The earth imaging resistivity survey was carried out in the dry period along the four above mentioned areas of the Gumti

  1. Waste Management Effluent Treatment Facility: Phase I. CAC basic data

    International Nuclear Information System (INIS)

    Gemar, D.W.; O'Leary, C.D.

    1984-01-01

    In order to expedite design and construction of the Waste Management Effluent Treatment Facility (WMETF), the project has been divided into two phases. Phase I consists of four storage basins and the associated transfer lines, diversion boxes, and control rooms. The design data pertaining to Phase I of the WMETF project are presented together with general background information and objectives for both phases. The project will provide means to store and decontaminate wastewater streams that are currently discharged to the seepage basins in F Area and H Area. This currently includes both routine process flows sent directly to the seepage basins and diversions of contaminated cooling water or storm water runoff that are stored in the retention basins before being pumped to the seepage basins

  2. Seepage studies through hydraulic structures and their foundations by inactive and radio tracers

    International Nuclear Information System (INIS)

    Ansari, Azher; Mahajan, N.M.; Kamble, M.D.

    1977-01-01

    In the last ten years extensive efforts have been made by the Central Water and Power Research Station, Pune to study seepage by means of inactive and radiotracers. Various inactive tracers like electrolytes and organic dyes and radiotracers like 82 Br and 3 H in the form of tritiated water have been used for location of source of seepage. Different techniques like borehole dilution, in situ detection at various observation points and analysis of water samples in liquid scintillation spectrometer in the laboratory have been employed to suit the field conditions. Some typical studies at river valley projects indicating the techniques are enumerated. (author)

  3. Fault-related CO2 degassing, geothermics, and fluid flow in southern California basins---Physiochemical evidence and modeling

    Energy Technology Data Exchange (ETDEWEB)

    Boles, James R. [Univ. of California, Santa Barbara, CA (United States); Garven, Grant [Tufts Univ., Medford, MA (United States)

    2015-08-04

    Our studies have had an important impact on societal issues. Experimental and field observations show that CO2 degassing, such as might occur from stored CO2 reservoir gas, can result in significant stable isotopic disequilibrium. In the offshore South Ellwood field of the Santa Barbara channel, we show how oil production has reduced natural seep rates in the area, thereby reducing greenhouse gases. Permeability is calculated to be ~20-30 millidarcys for km-scale fault-focused fluid flow, using changes in natural gas seepage rates from well production, and poroelastic changes in formation pore-water pressure. In the Los Angeles (LA) basin, our characterization of formation water chemistry, including stable isotopic studies, allows the distinction between deep and shallow formations waters. Our multiphase computational-based modeling of petroleum migration demonstrates the important role of major faults on geological-scale fluid migration in the LA basin, and show how petroleum was dammed up against the Newport-Inglewood fault zone in a “geologically fast” interval of time (less than 0.5 million years). Furthermore, these fluid studies also will allow evaluation of potential cross-formational mixing of formation fluids. Lastly, our new study of helium isotopes in the LA basin shows a significant leakage of mantle helium along the Newport Inglewood fault zone (NIFZ), at flow rates up to 2 cm/yr. Crustal-scale fault permeability (~60 microdarcys) and advective versus conductive heat transport rates have been estimated using the observed helium isotopic data. The NIFZ is an important deep-seated fault that may crosscut a proposed basin decollement fault in this heavily populated area, and appears to allow seepage of helium from the mantle sources about 30 km beneath Los Angeles. The helium study has been widely cited in recent weeks by the news media, both in radio and on numerous web sites.

  4. Fault-Related CO2 Degassing, Geothermics, and Fluid Flow in Southern California Basins--Physiochemical Evidence and Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Garven, Grant [Tufts Univ., Medford, MA (United States)

    2015-08-11

    Our studies have had an important impact on societal issues. Experimental and field observations show that CO2 degassing, such as might occur from stored CO2 reservoir gas, can result in significant stable isotopic disequilibrium. In the offshore South Ellwood field of the Santa Barbara channel, we show how oil production has reduced natural seep rates in the area, thereby reducing greenhouse gases. Permeability is calculated to be ~20-30 millidarcys for km-scale fault-focused fluid flow, using changes in natural gas seepage rates from well production, and poroelastic changes in formation pore-water pressure. In the Los Angeles (LA) basin, our characterization of formation water chemistry, including stable isotopic studies, allows the distinction between deep and shallow formations waters. Our multiphase computational-based modeling of petroleum migration demonstrates the important role of major faults on geological-scale fluid migration in the LA basin, and show how petroleum was dammed up against the Newport-Inglewood fault zone in a “geologically fast” interval of time (less than 0.5 million years). Furthermore, these fluid studies also will allow evaluation of potential cross-formational mixing of formation fluids. Lastly, our new study of helium isotopes in the LA basin shows a significant leakage of mantle helium along the Newport Inglewood fault zone (NIFZ), at flow rates up to 2 cm/yr. Crustal-scale fault permeability (~60 microdarcys) and advective versus conductive heat transport rates have been estimated using the observed helium isotopic data. The NIFZ is an important deep-seated fault that may crosscut a proposed basin decollement fault in this heavily populated area, and appears to allow seepage of helium from the mantle sources about 30 km beneath Los Angeles. The helium study has been widely cited in recent weeks by the news media, both in radio and on numerous web sites.

  5. Unsaturated Seepage Analysis of Cracked Soil including Development Process of Cracks

    Directory of Open Access Journals (Sweden)

    Ling Cao

    2016-01-01

    Full Text Available Cracks in soil provide preferential pathways for water flow and their morphological parameters significantly affect the hydraulic conductivity of the soil. To study the hydraulic properties of cracks, the dynamic development of cracks in the expansive soil during drying and wetting has been measured in the laboratory. The test results enable the development of the relationships between the cracks morphological parameters and the water content. In this study, the fractal model has been used to predict the soil-water characteristic curve (SWCC of the cracked soil, including the developmental process of the cracks. The cracked expansive soil has been considered as a crack-pore medium. A dual media flow model has been developed to simulate the seepage characteristics of the cracked expansive soil. The variations in pore water pressure at different part of the model are quite different due to the impact of the cracks. This study proves that seepage characteristics can be better predicted if the impact of cracks is taken into account.

  6. Microbial community changes along the active seepage site of one cold seep in the Red Sea.

    KAUST Repository

    Cao, Huiluo

    2015-07-21

    The active seepage of the marine cold seeps could be a critical process for the exchange of energy between the submerged geosphere and the sea floor environment through organic-rich fluids, potentially even affecting surrounding microbial habitats. However, few studies have investigated the associated microbial community changes. In the present study, 16S rRNA genes were pyrosequenced to decipher changes in the microbial communities from the Thuwal seepage point in the Red Sea to nearby marine sediments in the brine pool, normal marine sediments and water, and benthic microbial mats. An unexpected number of reads from unclassified groups were detected in these habitats; however, the ecological functions of these groups remain unresolved. Furthermore, ammonia-oxidizing archaeal community structures were investigated using the ammonia monooxygenase subunit A (amoA) gene. Analysis of amoA showed that planktonic marine habitats, including seeps and marine water, hosted archaeal ammonia oxidizers that differed from those in microbial mats and marine sediments, suggesting modifications of the ammonia oxidizing archaeal (AOA) communities along the environmental gradient from active seepage sites to peripheral areas. Changes in the microbial community structure of AOA in different habitats (water vs. sediment) potentially correlated with changes in salinity and oxygen concentrations. Overall, the present results revealed for the first time unanticipated novel microbial groups and changes in the ammonia-oxidizing archaea in response to environmental gradients near the active seepages of a cold seep.

  7. Microbial community changes along the active seepage site of one cold seep in the Red Sea.

    KAUST Repository

    Cao, Huiluo; Zhang, Weipeng; Wang, Yong; Qian, Pei-Yuan

    2015-01-01

    The active seepage of the marine cold seeps could be a critical process for the exchange of energy between the submerged geosphere and the sea floor environment through organic-rich fluids, potentially even affecting surrounding microbial habitats. However, few studies have investigated the associated microbial community changes. In the present study, 16S rRNA genes were pyrosequenced to decipher changes in the microbial communities from the Thuwal seepage point in the Red Sea to nearby marine sediments in the brine pool, normal marine sediments and water, and benthic microbial mats. An unexpected number of reads from unclassified groups were detected in these habitats; however, the ecological functions of these groups remain unresolved. Furthermore, ammonia-oxidizing archaeal community structures were investigated using the ammonia monooxygenase subunit A (amoA) gene. Analysis of amoA showed that planktonic marine habitats, including seeps and marine water, hosted archaeal ammonia oxidizers that differed from those in microbial mats and marine sediments, suggesting modifications of the ammonia oxidizing archaeal (AOA) communities along the environmental gradient from active seepage sites to peripheral areas. Changes in the microbial community structure of AOA in different habitats (water vs. sediment) potentially correlated with changes in salinity and oxygen concentrations. Overall, the present results revealed for the first time unanticipated novel microbial groups and changes in the ammonia-oxidizing archaea in response to environmental gradients near the active seepages of a cold seep.

  8. Optimization of Multiple Seepage Piping Parameters to Maximize the Critical Hydraulic Gradient in Bimsoils

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2017-10-01

    Full Text Available Seepage failure in the form of piping can strongly influence the stability of block-in-matrix-soils (bimsoils, as well as weaken and affect the performance of bimsoil structures. The multiple-factor evaluation and optimization play a crucial role in controlling the seepage failure in bimsoil. The aim of this study is to improve the ability to control the piping seepage failure in bimsoil. In this work, the response surface method (RSM was employed to evaluate and optimize the multiple piping parameters to maximize the critical hydraulic gradient (CHG, in combination with experimental modeling based on a self-developed servo-controlled flow-erosion-stress coupled testing system. All of the studied specimens with rock block percentage (RBP of 30%, 50%, and 70% were produced as a cylindrical shape (50 mm diameter and 100 mm height by compaction tests. Four uncertain parameters, such as RBP, soil matrix density, confining pressure, and block morphology were used to fit an optimal response of the CHG. The sensitivity analysis reveals the influential order of the studied factors to CHG. It is found that RBP is the most sensitive factor, the CHG decreases with the increase of RBP, and CHG increases with the increase of confining pressure, soil matrix density, and block angularity.

  9. Focused groundwater discharge of phosphorus to a eutrophic seepage lake (Lake Væng, Denmark): implications for lake ecological state and restoration

    DEFF Research Database (Denmark)

    Kidmose, Jacob; Nilsson, Bertel; Engesgaard, Peter

    2013-01-01

    and borehole data. Discharge was found to be much focused and opposite to expected increase away from the shoreline. The average total phosphorus concentration in discharging groundwater sampled just beneath the lakebed was 0.162 mg TP/l and thereby well over freshwater ecological thresholds (0...... paths through the aquifer–lakebed interface either being overland flow through a seepage face, or focused in zones with very high discharge rates. In-lake springs have measured discharge of up to 7.45 m3 per m2 of lakebed per day. These findings were based on seepage meter measurements at 18 locations...

  10. Radioactive Seepage through Groundwater Flow from the Uranium Mines, Namibia

    Directory of Open Access Journals (Sweden)

    Tamiru Abiye

    2017-02-01

    Full Text Available The study focused on the seepage of uranium from unlined tailing dams into the alluvial aquifer in the Gawib River floodplain in Namibia where the region solely relies on groundwater for its economic activities as a result of arid climatic condition. The study reviewed previous works besides water sample collection and analyses for major ions, metals and environmental isotopes in addition to field tests on physico-chemical parameters (pH, Electrical Conductivity, Redox and T. Estimation of seepage velocity (true velocity of groundwater flow has been conducted in order to understand the extent of radioactive plume transport. The hydrochemistry, stable isotopes and tritium results show that there is uranium contamination from the unlined uranium tailings in the Gawib shallow aquifer system which suggests high permeability of the alluvial aquifer facilitating groundwater flow in the arid region. The radioactive contaminants could spread into the deeper aquifer system through the major structures such as joints and faults. The contamination plume could also spread downstream into the Swakop River unless serious interventions are employed. There is also a very high risk of the plume to reach the Atlantic Ocean through seasonal flash floods that occurs in the area.

  11. Effect of Seepage on Change in Stress Distribution Scenario in Static and Seismic Behaviour of Earthen Dams

    Directory of Open Access Journals (Sweden)

    Nandi N.

    2018-02-01

    Full Text Available The present study makes an effort to understand the damage of earthen dams under static and seismic loading condition. To make the investigation more realistic, behaviour of earthen dams considering the occurrence of a phreatic line indicating the submerged zone due to seepage within the dam body is considered. In case of earthen dams, homogeneous or nonhomogeneous, the consideration of the occurrence of a phreatic line or seepage line through the dam body is an important part of the earthen dam design methodology. The impervious material properties in the submerged zone below the phreatic line due to seepage may differ a lot in magnitudes as compared to the value of the same materials lying above this line. Hence, to have the exact stress distribution scenarios within the earthen dam, the different material properties above and below the phreatic line are considered in this present study. The study is first carried out by two-dimensional as well as three-dimensional finite element analysis under static loading condition. The work is further extended to observe the effect of seepage due to the consideration of the phreatic line on dynamic characteristics of earthen dams. Free vibration analysis and seismic analysis based on the Complete Quadratic Combination (CQC method by considering twodimensional and three-dimensional modeling are carried out to present the frequencies, mode shapes and the stress distribution pattern of the earthen dam.

  12. Albedo and land surface temperature shift in hydrocarbon seepage potential area, case study in Miri Sarawak Malaysia

    International Nuclear Information System (INIS)

    Suherman, A; Rahman, M Z A; Busu, I

    2014-01-01

    The presence of hydrocarbon seepage is generally associated with rock or mineral alteration product exposures, and changes of soil properties which manifest with bare development and stress vegetation. This alters the surface thermodynamic properties, changes the energy balance related to the surface reflection, absorption and emission, and leads to shift in albedo and LST. Those phenomena may provide a guide for seepage detection which can be recognized inexpensively by remote sensing method. District of Miri is used for study area. Available topographic maps of Miri and LANDSAT ETM+ were used for boundary construction and determination albedo and LST. Three land use classification methods, namely fixed, supervised and NDVI base classifications were employed for this study. By the intensive land use classification and corresponding statistical comparison was found a clearly shift on albedo and land surface temperature between internal and external seepage potential area. The shift shows a regular pattern related to vegetation density or NDVI value. In the low vegetation density or low NDVI value, albedo of internal area turned to lower value than external area. Conversely in the high vegetation density or high NDVI value, albedo of internal area turned to higher value than external area. Land surface temperature of internal seepage potential was generally shifted to higher value than external area in all of land use classes. In dense vegetation area tend to shift the temperature more than poor vegetation area

  13. Albedo and land surface temperature shift in hydrocarbon seepage potential area, case study in Miri Sarawak Malaysia

    Science.gov (United States)

    Suherman, A.; Rahman, M. Z. A.; Busu, I.

    2014-02-01

    The presence of hydrocarbon seepage is generally associated with rock or mineral alteration product exposures, and changes of soil properties which manifest with bare development and stress vegetation. This alters the surface thermodynamic properties, changes the energy balance related to the surface reflection, absorption and emission, and leads to shift in albedo and LST. Those phenomena may provide a guide for seepage detection which can be recognized inexpensively by remote sensing method. District of Miri is used for study area. Available topographic maps of Miri and LANDSAT ETM+ were used for boundary construction and determination albedo and LST. Three land use classification methods, namely fixed, supervised and NDVI base classifications were employed for this study. By the intensive land use classification and corresponding statistical comparison was found a clearly shift on albedo and land surface temperature between internal and external seepage potential area. The shift shows a regular pattern related to vegetation density or NDVI value. In the low vegetation density or low NDVI value, albedo of internal area turned to lower value than external area. Conversely in the high vegetation density or high NDVI value, albedo of internal area turned to higher value than external area. Land surface temperature of internal seepage potential was generally shifted to higher value than external area in all of land use classes. In dense vegetation area tend to shift the temperature more than poor vegetation area.

  14. Simulated runoff at many stream locations in the Methow River Basin, Washington

    Science.gov (United States)

    Mastin, Mark C.

    2015-01-01

    A collaborative Bureau of Reclamation-U.S. Geological Survey (USGS) team has been brought together to incorporate a conceptual geomorphic-habitat model with a process-based trophic model to understand the processes important to stream habitat for anadromous fish populations. The Methow River Basin was selected as a test basin for this hybrid geomorphic-habitat/trophic model, and one of the required model inputs is long-term daily runoff at reaches with potential habitat. Leveraging the existence of a watershed model that was constructed for the Methow River Basin by the USGS, the team approached the USGS at the Washington Water Science Center to resurrect the original model and to simulate runoff at many locations in the basin to test the trophic model. Thirteen new flow-routing sites were added to the model, creating a total of 61 sites in the basin where daily runoff was simulated and provided as output. The input file that contains observed meteorological data that drives the watershed model and observed runoff data for comparisons with simulated runoff was extended from water year 2001 to water year 2013 using data from 18 meteorological sites and 12 observed runoff sites. The watershed model included simulation of 16 irrigation diversions that simulated 50-percent water loss through canal seepage. Irrigation was simulated as a constant application of 0.2 inches per day to during the irrigation season, May 1–October 7.

  15. Hydrocarbon Degradation in Caspian Sea Sediment Cores Subjected to Simulated Petroleum Seepage in a Newly Designed Sediment-Oil-Flow-Through System

    Directory of Open Access Journals (Sweden)

    Tina Treude

    2017-04-01

    Full Text Available The microbial community response to petroleum seepage was investigated in a whole round sediment core (16 cm length collected nearby natural hydrocarbon seepage structures in the Caspian Sea, using a newly developed Sediment-Oil-Flow-Through (SOFT system. Distinct redox zones established and migrated vertically in the core during the 190 days-long simulated petroleum seepage. Methanogenic petroleum degradation was indicated by an increase in methane concentration from 8 μM in an untreated core compared to 2300 μM in the lower sulfate-free zone of the SOFT core at the end of the experiment, accompanied by a respective decrease in the δ13C signal of methane from -33.7 to -49.5‰. The involvement of methanogens in petroleum degradation was further confirmed by methane production in enrichment cultures from SOFT sediment after the addition of hexadecane, methylnapthalene, toluene, and ethylbenzene. Petroleum degradation coupled to sulfate reduction was indicated by the increase of integrated sulfate reduction rates from 2.8 SO42-m-2 day-1 in untreated cores to 5.7 mmol SO42-m-2 day-1 in the SOFT core at the end of the experiment, accompanied by a respective accumulation of sulfide from 30 to 447 μM. Volatile hydrocarbons (C2–C6 n-alkanes passed through the methanogenic zone mostly unchanged and were depleted within the sulfate-reducing zone. The amount of heavier n-alkanes (C10–C38 decreased step-wise toward the top of the sediment core and a preferential degradation of shorter (C30 was seen during the seepage. This study illustrates, to the best of our knowledge, for the first time the development of methanogenic petroleum degradation and the succession of benthic microbial processes during petroleum passage in a whole round sediment core.

  16. Hydrocarbon Degradation in Caspian Sea Sediment Cores Subjected to Simulated Petroleum Seepage in a Newly Designed Sediment-Oil-Flow-Through System.

    Science.gov (United States)

    Mishra, Sonakshi; Wefers, Peggy; Schmidt, Mark; Knittel, Katrin; Krüger, Martin; Stagars, Marion H; Treude, Tina

    2017-01-01

    The microbial community response to petroleum seepage was investigated in a whole round sediment core (16 cm length) collected nearby natural hydrocarbon seepage structures in the Caspian Sea, using a newly developed Sediment-Oil-Flow-Through (SOFT) system. Distinct redox zones established and migrated vertically in the core during the 190 days-long simulated petroleum seepage. Methanogenic petroleum degradation was indicated by an increase in methane concentration from 8 μM in an untreated core compared to 2300 μM in the lower sulfate-free zone of the SOFT core at the end of the experiment, accompanied by a respective decrease in the δ 13 C signal of methane from -33.7 to -49.5‰. The involvement of methanogens in petroleum degradation was further confirmed by methane production in enrichment cultures from SOFT sediment after the addition of hexadecane, methylnapthalene, toluene, and ethylbenzene. Petroleum degradation coupled to sulfate reduction was indicated by the increase of integrated sulfate reduction rates from 2.8 SO 4 2- m -2 day -1 in untreated cores to 5.7 mmol SO 4 2- m -2 day -1 in the SOFT core at the end of the experiment, accompanied by a respective accumulation of sulfide from 30 to 447 μM. Volatile hydrocarbons (C2-C6 n -alkanes) passed through the methanogenic zone mostly unchanged and were depleted within the sulfate-reducing zone. The amount of heavier n -alkanes (C10-C38) decreased step-wise toward the top of the sediment core and a preferential degradation of shorter (C30) was seen during the seepage. This study illustrates, to the best of our knowledge, for the first time the development of methanogenic petroleum degradation and the succession of benthic microbial processes during petroleum passage in a whole round sediment core.

  17. Study of Movement and Seepage Along Levees Using DINSAR and the Airborne UAVSAR Instrument

    Science.gov (United States)

    Jones, Cathleen E.; Bawden, Gerald; Deverel, Steven; Dudas, Joel; Hensley, Scott

    2012-01-01

    We have studied the utility of high resolution SAR (synthetic aperture radar) for levee monitoring using UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) data collected along the dikes and levees in California's Sacramento-San Joaquin Delta and along the lower Mississippi River. Our study has focused on detecting and tracking changes that are indicative of potential problem spots, namely deformation of the levees, subsidence along the levee toe, and seepage through the levees, making use of polarimetric and interferometric SAR techniques. Here was present some results of those studies, which show that high resolution, low noise SAR imaging could supplement more traditional ground-based monitoring methods by providing early indicators of seepage and deformation.

  18. Sources, extent and history of methane seepage on the continental shelf off northern Norway

    Science.gov (United States)

    Sauer, Simone; Lepland, Aivo; Chand, Shyam; Schubert, Carsten J.; Eichinger, Florian; Knies, Jochen

    2014-05-01

    Active natural hydrocarbon gas seepage was recently discovered in the Hola area on the continental shelf off Vesterålen, northern Norway. We conducted acoustic and geochemical investigations to assess the modern and past extent, source and pathways of the gas seepage . Water column echosounder surveys showed bubble plumes up to several tens of metres above the seafloor. Analyses of dissolved methane in the water column indicated slightly elevated concentrations (50 nM) close to the seafloor. To identify fluxes and origin of methane in the sediments we analysed sediment pore water chemistry, the isotopic composition of methane and of dissolved inorganic carbon (d13CCH4, d2HCH4, d13CDIC) in three closely spaced (

  19. 77 FR 98 - Commission Information Collection Activities, Proposed Collection (FERC-716); Comment Request...

    Science.gov (United States)

    2012-01-03

    ... requirements of FERC-716 (``Good Faith Request for Transmission Service and Response by Transmitting Utility..., provide standards by which the Commission determines if and when a valid good faith request for... 12 components of a good faith estimate and 5 components of a reply to a good faith request. Action...

  20. Water quality, discharge, and groundwater levels in the Palomas, Mesilla, and Hueco Basins in New Mexico and Texas from below Caballo Reservoir, New Mexico, to Fort Quitman, Texas, 1889-2013

    Science.gov (United States)

    McKean, Sarah E.; Matherne, Anne Marie; Thomas, Nicole

    2014-01-01

    The U.S. Geological Survey, in cooperation with the New Mexico Environment Department, compiled data from various sources to develop a dataset that can be used to conduct an assessment of the total dissolved solids in surface water and groundwater of the Palomas, Mesilla, and Hueco Basins in New Mexico and Texas, from below Caballo Reservoir, N. Mex., to Fort Quitman, Tex. Data include continuous surface-water discharge records at various locations on the Rio Grande; surface-water-quality data for the Rio Grande collected at selected locations in the Palomas, Mesilla, and Hueco Basins; groundwater levels and groundwater-quality data collected from selected wells in the Palomas and Mesilla Basins; and data from several seepage investigations conducted on the Rio Grande and selected drains in the Mesilla Basin.

  1. Theoretical and Experimental Investigation of Characteristics of Single Fracture Stress-Seepage Coupling considering Microroughness

    Directory of Open Access Journals (Sweden)

    Shengtong Di

    2017-01-01

    Full Text Available Based on the results of the test among the joint roughness coefficient (JRC of rock fracture, mechanical aperture, and hydraulic aperture proposed by Barton, this paper deduces and proposes a permeability coefficient formula of single fracture stress-seepage coupling considering microroughness by the introduction of effect variables considering the microparticle size and structural morphology of facture surface. Quasi-sandstone fracture of different particle size is made by the laboratory test, and the respective modification is made on the coupled shear-seepage test system of JAW-600 rock. Under this condition, the laboratory test of stress-seepage coupling of fracture of different particle size is carried out. The test results show that, for the different particle-sized fracture surface of the same JRC, the permeability coefficient is different, which means the smaller particle size, the smaller permeability coefficient, and the larger particle size, the larger permeability coefficient; with the increase of cranny hydraulic pressure, the permeability coefficient increases exponentially, and under the same cranny hydraulic pressure, there is relation of power function between the permeability coefficient and normal stress. Meanwhile, according to the theoretical formula, the microroughness coefficient of the fractures with different particle size is obtained by the calculation, and its accuracy and validity are verified by experiments. The theoretical verification values are in good agreement with the measured values.

  2. Hydrogeology and water quality of the Chakari Basin, Afghanistan

    Science.gov (United States)

    Mack, Thomas J.; Chornack, Michael P.; Flanagan, Sarah M.; Chalmers, Ann T.

    2014-01-01

    The hydrogeology and water quality of the Chakari Basin, a 391-square-kilometer (km2) watershed near Kabul, Afghanistan, was assessed by the U.S. Geological Survey and the Afghanistan Geological Survey to provide an understanding of the water resources in an area of Afghanistan with considerable copper and other mineral resources. Water quality, chemical, and isotopic samples were collected at eight wells, four springs, one kareze, and the Chakari River in a basin-fill aquifer in the Chakari Basin by the Afghanistan Geological Survey. Results of water-quality analyses indicate that some water samples in the basin had concentrations of chemical constituents that exceeded World Health Organization guidelines for nitrate, sodium, and dissolved solids and some of the samples also had elevated concentrations of trace elements, such as copper, selenium, strontium, uranium, and zinc. Chemical and isotopic analyses, including for tritium, chlorofluorocarbons, and carbon-14, indicate that most wells contain water with a mixture of ages from young (years to decades) to old (several thousand years). Three wells contained groundwater that had modeled ages ranging from 7,200 to 7,900 years old. Recharge from precipitation directly on the basin-fill aquifer, which covers an area of about 150 km2, is likely to be very low (7 × 10-5 meters per day) or near zero. Most recharge to this aquifer is likely from rain and snowmelt on upland areas and seepage losses and infiltration of water from streams crossing the basin-fill aquifer. It is likely that the older water in the basin-fill aquifer is groundwater that has travelled along long and (or) slow flow paths through the fractured bedrock mountains surrounding the basin. The saturated basin-fill sediments in most areas of the basin are probably about 20 meters thick and may be about 30 to 60 meters thick in most areas near the center of the Chakari Basin. The combination of low recharge and little storage indicates that groundwater

  3. Gas seepage on an intertidal site: Torry Bay, Firth of Forth, Scotland

    Energy Technology Data Exchange (ETDEWEB)

    Judd, A.G.; Sim, R.; Kingston, P.; McNally, J. [University of Sunderland, Sunderland (United Kingdom)

    2002-07-01

    Gas seeps occurring on tidal flats on the northern shore of the inner Firth of Forth are described. The principal gas is methane, which is considered to come from the coal-bearing rocks of the Lower Limestone Series (Carboniferous); either naturally or from abandoned coal workings. Seep activity has been known, at the site for several years, and it is suggested that the presence of white filamentous bacteria (Beggiatoa sp.) and a carbonate precipitate are indicative of long-term seepage. Comparative studies at the seep and at a control site revealed that the seeps have only a marginal effect on the intertidal fauna. Migration of gas through the thin ({lt} 2 m) surficial sediments appears to be controlled by the topography of a gravel layer, seeps preferentially occurring where the top of the gravel is closest to the surface. The total gas emission from 70 to 100 individual seepage vents is estimated at approximate to 1 tonne CH{sub 4} yr{sup -1}, the majority of which is emitted direct to the atmosphere.

  4. Emission of Methane and Heavier Alkanes From the La Brea Tar Pits Seepage Area, Los Angeles

    Science.gov (United States)

    Etiope, G.; Doezema, L. A.; Pacheco, C.

    2017-11-01

    Natural hydrocarbon (oil and gas) seeps are widespread in Los Angeles, California, due to gas migration, along faults, from numerous subsurface petroleum fields. These seeps may represent important natural contributors of methane (CH4) and heavier alkanes (C2-C4) to the atmosphere, in addition to anthropogenic fossil fuel and biogenic sources. We measured the CH4 flux by closed-chamber method from the La Brea Tar Pits park (0.1 km2), one of the largest seepage sites in Los Angeles. The gas seepage occurs throughout the park, not only from visible oil-asphalt seeps but also diffusely from the soil, affecting grass physiology. About 500 kg CH4 d-1 is emitted from the park, especially along a belt of enhanced degassing that corresponds to the 6th Street Fault. Additional emissions are from bubble plumes in the lake within the park (order of 102-103 kg d-1) and at the intersection of Wilshire Boulevard and Curson Avenue (>130 kg d-1), along the same fault. The investigated area has the highest natural gas flux measured thus far for any onshore seepage zone in the USA. Gas migration, oil biodegradation, and secondary methanogenesis altered the molecular composition of the original gas accumulated in the Salt Lake Oil Field (>300 m deep), leading to high C1/C2+ and i-butane/n-butane ratios. These molecular alterations can be important tracers of natural seepage and should be considered in the atmospheric modeling of the relative contribution of fossil fuel (anthropogenic fugitive emission and natural geologic sources) versus biogenic sources of methane, on local and global scales.

  5. Application of short-range photogrammetry for monitoring seepage erosion of riverbank by laboratory experiments

    Science.gov (United States)

    Masoodi, A.; Noorzad, A.; Majdzadeh Tabatabai, M. R.; Samadi, A.

    2018-03-01

    Temporal and spatial monitoring play a significant role in evaluating and examining the riverbank morphology and its spatiotemporal changes. Unlike the terrestrial laser scanners, other previously used methods such as satellite images, total station surveying, and erosion pins have limited application to quantify the small-scale bank variations due to the lack of rapid survey and resolution in data acquisition. High cost, lack of availability, specialized equipment and hard movement of laser scanners make it necessary to develop new accurate, economical and easily available methods. The present study aims to test the Kinect photogrametric technology for measuring and assessing riverbank variations in laboratory environment. For this purpose, three models of layered soil blocks for three different levels of groundwater (i.e. 24, 34 and 44 cm) were designed to investigate the seepage erosion behavior experimentally. The results indicate the high accuracy of Kinect in measuring the bank erosion cavity dimensions (i.e., 0.5% error) with high spatial resolution data (i.e. 300,000 points per frame). The high speed of Kinect in riverbank scanning enables the analysis of time variations of mechanisms such as seepage erosion which occurs rather rapidly. The results confirmed that there is a power relationship between the seepage gradient and the time of the bank failure with a determination coefficient of 0.97. Moreover, an increase in the level of groundwater on the riverbank increases the rate of undercutting retreat that caused more rapid failure of the riverbank.

  6. Application of environmental isotopes and hydrochemistry in the identification of source of seepage and likely connection with lake water in Lesser Himalaya, Uttarakhand, India

    Science.gov (United States)

    Rai, Shive Prakash; Singh, Dharmaveer; Rai, Ashwani Kumar; Kumar, Bhishm

    2017-12-01

    Oxygen (δ^{18}O) and hydrogen (δ2H and 3H) isotopes of water, along with their hydrochemistry, were used to identify the source of a newly emerged seepage water in the downstream of Lake Nainital, located in the Lesser Himalayan region of Uttarakhand, India. A total of 57 samples of water from 19 different sites, in and around the seepage site, were collected. Samples were analysed for chemical tracers like Ca^{++}, Mg^{++}, Na+, K+, {SO4}^{-} and Cl- using an Ion Chromatograph (Dionex IC-5000). A Dual Inlet Isotope Ratio Mass Spectrometer (DIIRMS) and an Ultra-Low Level Liquid Scintillation Counter (ULLSC), were used in measurements of stable isotopes (δ2H and δ^{18}O) and a radioisotope (3H), respectively. Results obtained in this study repudiate the possibility of any likely connection between seepage water and the lake water, and indicate that the source of seepage water is mainly due to locally recharged groundwater. The study suggests that environmental isotopes (δ2H, δ^{18}O and 3H) can effectively be used as `tracers' in the detection of the source of seepage water in conjunction with other hydrochemical tracers, and can help in water resource management and planning.

  7. Modelling Technique for the Assessment of the Sub-Soil Drain for Groundwater Seepage Remediation

    Directory of Open Access Journals (Sweden)

    Tajul Baharuddin Mohamad Faizal

    2017-01-01

    Full Text Available Groundwater simulation technique was carried out for examining the performance of sub-soil drain at problematic site area. Subsoil drain was proposed as one of solution for groundwater seepage occurred at the slope face by reducing groundwater table at Taman Botani Park Kuala Lumpur. The simulation technique used Modular Three-Dimensional Finite Difference Groundwater Flow (MODFLOW software. In transient conditions, the results of simulation showed that heads increases surpass 1 to 2 m from the elevation level of the slope area that caused groundwater seepage on slope face. This study attempt to decrease the heads increase surpass by using different sub-soil drain size in simulation technique. The sub-soil drain capable to decline the heads ranges of 1 to 2 m.

  8. Geology and ground-water resources of the Douglas basin, Arizona, with a section on chemical quality of the ground water

    Science.gov (United States)

    Coates, Donald Robert; Cushman, R.L.; Hatchett, James Lawrence

    1955-01-01

    . The water collects in streams that lose much of their flow into the coarse sediments that fringe the mountains. Part of the water ultimately percolates into the zone of saturation. High evaporation rates, vegetative use, and the presence of caliche and clay at shallow depth in the interstream areas of the valley floor prevent important recharge of the ground-water reservoir from direct rainfall or seepage of water applied for irrigation. The total recharge into the ground-water reservoir of the Douglas basin was about 20,000 acre-feet in 1951. Ground water is discharged from the basin by evapotranspiration, by effluent seepage into Whitewater Draw and underflow out of the basin, and by pumping. In 1951, the total amount of ground water discharged was about 50,000 acre-feet, of which more than 41,000 acre-feet was pumped from wells. Ground water used in excess of recharge is withdrawn from storage, causing a decline in the water table. Maximum declines have occurred in the heavily pumped Elfrida area, where a decline of more than 11 feet occurred in the 5-

  9. Groundwater pollution risk mapping for the Eocene aquifer of the Oum Er-Rabia basin, Morocco

    Science.gov (United States)

    Ettazarini, Said

    2006-11-01

    Sustainable development requires the management and preservation of water resources indispensable for all human activities. When groundwater constitutes the main water resource, vulnerability maps therefore are an important tool for identifying zones of high pollution risk and taking preventive measures in potential pollution sites. The vulnerability assessment for the Eocene aquifer in the Moroccan basin of Oum Er-Rabia is based on the DRASTIC method that uses seven parameters summarizing climatic, geological, and hydrogeological conditions controlling the seepage of pollutant substances to groundwater. Vulnerability maps were produced by using GIS techniques and applying the “generic” and “agricultural” models according to the DRASTIC charter. Resulting maps revealed that the aquifer is highly vulnerable in the western part of the basin and areas being under high contamination risk are more extensive when the “agricultural” model was applied.

  10. A steady state solution for ditch drainage problem with special reference to seepage face and unsaturated zone flow contribution: Derivation of a new drainage spacing eqaution

    Science.gov (United States)

    Yousfi, Ammar; Mechergui, Mohammed

    2016-04-01

    The seepage face is an important feature of the drainage process when recharge occurs to a permeable region with lateral outlets. Examples of the formation of a seepage face above the downstream water level include agricultural land drained by ditches. Flow problem to these drains has been investigated extensively by many researchers (e.g. Rubin, 1968; Hornberger et al. 1969; Verma and Brutsaert, 1970; Gureghian and Youngs, 1975; Vauclin et al., 1975; Skaggs and Tang, 1976; Youngs, 1990; Gureghian, 1981; Dere, 2000; Rushton and Youngs, 2010; Youngs, 2012; Castro-Orgaz et al., 2012) and may be tackled either using variably saturated flow models, or the complete 2-D solution of Laplace equation, or using the Dupuit-Forchheimer approximation; the most widely accepted methods to obtain analytical solutions for unconfined drainage problems. However, the investigation reported by Clement et al. (1996) suggest that accounting for the seepage face alone, as in the fully saturated flow model, does not improve the discharge estimate because of disregarding flow the unsaturated zone flow contribution. This assumption can induce errors in the location of the water table surface and results in an underestimation of the seepage face and the net discharge (e.g. Skaggs and Tang, 1976; Vauclin et al., 1979; Clement et al., 1996). The importance of the flow in the unsaturated zone has been highlighted by many authors on the basis of laboratory experiments and/or numerical experimentations (e.g. Rubin, 1968; Verma and Brutsaert, 1970; Todsen, 1973; Vauclin et al., 1979; Ahmad et al., 1993; Anguela, 2004; Luthin and Day, 1955; Shamsai and Narasimhan, 1991; Wise et al., 1994; Clement et al., 1996; Boufadel et al., 1999; Romano et al., 1999; Kao et al., 2001; Kao, 2002). These studies demonstrate the failure of fully saturated flow models and suggested that the error made when using these models not only depends on soil properties but also on the infiltration rate as reported by Kao et

  11. Faults as Windows to Monitor Gas Seepage: Application to CO2 Sequestration and CO2-EOR

    Directory of Open Access Journals (Sweden)

    Ronald W. Klusman

    2018-03-01

    Full Text Available Monitoring of potential gas seepage for CO2 sequestration and CO2-EOR (Enhanced Oil Recovery in geologic storage will involve geophysical and geochemical measurements of parameters at depth and at, or near the surface. The appropriate methods for MVA (Monitoring, Verification, Accounting are needed for both cost and technical effectiveness. This work provides an overview of some of the geochemical methods that have been demonstrated to be effective for an existing CO2-EOR (Rangely, CA, USA and a proposed project at Teapot Dome, WY, USA. Carbon dioxide and CH4 fluxes and shallow soil gas concentrations were measured, followed by nested completions of 10-m deep holes to obtain concentration gradients. The focus at Teapot Dome was the evaluation of faults as pathways for gas seepage in an under-pressured reservoir system. The measurements were supplemented by stable carbon and oxygen isotopic measurements, carbon-14, and limited use of inert gases. The work clearly demonstrates the superiority of CH4 over measurements of CO2 in early detection and quantification of gas seepage. Stable carbon isotopes, carbon-14, and inert gas measurements add to the verification of the deep source. A preliminary accounting at Rangely confirms the importance of CH4 measurements in the MVA application.

  12. Coupled LBM-DEM Three-phase Simulation on Seepage of CO2 Stored under the Seabed.

    Science.gov (United States)

    Kano, Y.; Sato, T.

    2017-12-01

    Concerning the seepage of CO2 stored in a subsea formation, CO2 bubble/droplet rises to the sea-surface dissolving into the seawater, and the acidification of local seawater will be a problem. Previous research indicated that seepage rate and bubble size significantly affect its behaviour (Kano et al., 2009; Dewar et al., 2013). On the other hand, Kawada's experiments (2014) indicated that grain size affects formation of gas channels and bubbles through granular media. CO2 seepage through marine sediments probably shows similar behaviour. Additionally, such mobilisation and displacement of sand grains by gas migration may also cause capillary fracturing of CO2 in the reservoir and seal. To predict these phenomena, it is necessary to reveal three-phase behaviour of gas-water-sediment grains. We built gas-liquid-solid three-phase flow 3D simulator by coupling LBM-DEM program, and simulation results showed that the mobilisation of sand grain forms gas channels and affects bubble formation compared with that through solid porous media (Kano and Sato, 2017). In this presentation, we will report simulation results on effects of porosity, grain size and gas flow rate on the formation of gas channels and bubble and their comparison with laboratory experimental data. The results indicate that porosity and grain size of sand gravels affect the width of formed gas channels and resulting formed bubble size on the order of supposed seepage rate in the CO2 storage and that in most of experiment's conditions. References: Abe, S., Place, D., Mora, P., 2004. Pure. Appl. Geophys., 161, 2265-2277. (accessed Aug 01, 2017). Dewar, M., Wei, W., McNeil, D., Chen, B., 2013. Marine Pollution Bulletin 73(2), 504-515. Kano, Y., Sato, T., Kita, J., Hirabayashi, S., Tabeta, S., 2009. Int. J. Greenhouse Gas Control, Vol. 3(5), 617-625. Kano, Y. and Sato, T., 2017. In Proceeding of GHGT-13, Lausanne, Switzerland, Nov. 14-18, 2016. Kawada, R. 2014. Graduation thesis. Faculty of Engineering, The

  13. Regeneration of Mature Norway Spruce Stands: Early Effects of Selective Cutting and Clear Cutting on Seepage Water Quality and Soil Fertility

    Directory of Open Access Journals (Sweden)

    Wendelin Weis

    2001-01-01

    Full Text Available The cutting of trees influences element turnover in the forest ecosystem. The reduction of plant uptake, as well as an increased mineralization and nitrification due to higher soil temperature and soil moisture, can lead to considerable losses of nutrients from the main rooting zone. This may result in a reduced soil fertility and a decrease in drinking water quality due to high nitrate concentrations in the seepage water. In Bavaria (Germany selective cutting is preferred to clear cutting when initiating the regeneration of Norway spruce stands with European beech. This paper summarizes the early effects of both forest management practices on soil fertility and seepage water quality for three different sites. Shown are the concentrations of nitrogen and base cations in the seepage water as well as the water and ion fluxes during the first year after tree cut. Nutrient inputs decreased on thinned plots and even more at clear-cuts. Nitrate concentrations in the seepage water are hardly affected by moderate thinning; however, on clear-cuts, the nitrate concentration increases significantly, and base cations are lost from the upper mineral soil. This effect is less obvious at sites where a dense ground vegetation, which is able to take up excess nitrogen, exists.

  14. Microseepage of methane to the atmosphere from the Dawanqi oil-gas field, Tarim Basin, China

    Science.gov (United States)

    Tang, Junhong; Xu, Yue; Wang, Guojian; Etiope, Giuseppe; Han, Wei; Yao, Zhitong; Huang, Jingang

    2017-04-01

    The microseepage of natural gas from subsurface hydrocarbon reservoirs is a widespread process in petroleum basins. On a global scale, microseepage represents an important natural source of atmospheric methane (CH4). To date, microseepage CH4 flux data have been obtained from 20 petroleum systems in North America, Europe, and Asia. While the seasonal variations of gas flux due to soil methanotrophic activity are known, the role of geological factors in controlling gas fluxes has been poorly investigated. Here we present new microseepage data from the Dawanqi oil-gas field located within the Tarim Basin (China), a petroleum system characterized by intense faulting and shallow (petroleum fields with active tectonics. Our results confirm that dry soil over petroleum fields can be a net source of atmospheric CH4 and its flux is primarily controlled by faulting, and reservoir depth and pressure. These factors shall be considered in global bottom-up seepage emission estimates.

  15. 12 CFR 716.12 - Limits on sharing of account number information for marketing purposes.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Limits on sharing of account number information... REGULATIONS AFFECTING CREDIT UNIONS PRIVACY OF CONSUMER FINANCIAL INFORMATION Limits on Disclosures § 716.12 Limits on sharing of account number information for marketing purposes. (a) General prohibition on...

  16. Dynamic behaviour of natural oil droplets through the water column in deep-water environment: the case of the Lower Congo Basin

    Science.gov (United States)

    Jatiault, R.; Dhont, D.; Loncke, L.; Durrieu De Madron, X.; Dubucq, D.; Channelliere, C.; Bourrin, F.

    2017-12-01

    Key words: Hydrocarbon seepage, Oil Slick, Lower Congo Basin, Underwater deflection, Deep-water Pockmark, Ascent speedThe space-borne imagery provides a significant means to locate active oil seeps and to estimate the expelled volume in the marine environment. The analysis of numerous overlapping satellite images revealed an abundant volume of 4400 m3 of oil naturally reaching the sea surface per year, expelled from more than a hundred seep sites through the Lower Congo Basin. The active seepage area is located in the distal compressional province of the basin where salt napes and squeezed diapirs. The integration of current data was used to link accurately sea surface manifestations of natural oil leakages with active fluid flow features on the seafloor. A mooring with ADCPs (Acoustic Doppler Current Profilers) distributed throughout the water column provided an efficient calibration tool to evaluate the horizontal deflection of oil droplets. Using a Eulerian propagation model that considered a range of probable ascent speeds, we estimated the oil migration pathways through the water column using two different approaches. The first approach consisted in simulating the backwards trajectory of oil droplets using sea surface oil slicks locations and concomitant current measurements. The second method analyzed the spatial spreading of the surfacing signatures of natural oil slicks based on 21 years of satellite observations. The location of the surfacing points of oil droplets at the sea surface is restricted to a circle of 2.5 km radius around the release point at the seafloor. Both approaches provided a range of ascent speeds of oil droplets between 3 to 8 cm.s-1. The low deflection values validate the near-vertical links between the average surfacing area of oil slicks at the sea surface with specific seafloor disturbances (i.e. pockmarks or mounds) known to expel fluids.

  17. Research on borehole stability of shale based on seepage-stress-damage coupling model

    Directory of Open Access Journals (Sweden)

    Xiaofeng Ran

    2014-01-01

    Full Text Available In oil drilling, one of the most complicated problems is borehole stability of shale. Based on the theory of continuum damage mechanics, a modified Mohr-Coulomb failure criterion according to plastic damage evolution and the seepage-stress coupling is established. Meanwhile, the damage evolution equation which is based on equivalent plastic strain and the permeability evolution equation of shale are proposed in this paper. The physical model of borehole rock for a well in China western oilfield is set up to analyze the distribution of damage, permeability, stress, plastic strain and displacement. In the calculation process, the influence of rock damage to elastic modulus, cohesion and permeability is involved by writing a subroutine for ABAQUS. The results show that the rock damage evolution has a significant effect to the plastic strain and stress in plastic zone. Different drilling fluid density will produce different damage in its value, range and type. This study improves the theory of mechanical mechanism of borehole collapse and fracture, and provides a reference for the further research of seepage-stress-chemical-damage coupling of wall rock.

  18. Correlation of Self Potential and Ground Magnetic Survey Techniques to Investigate Fluid Seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia

    Directory of Open Access Journals (Sweden)

    Tajudeen O. Adeeko

    2018-05-01

    Full Text Available One of the substantial of geophysics is to investigate the subsurface condition of the earth (groundwater using appropriate geophysical techniques. In this research the correlation of self potential (SP and ground magnetic methods was used to investigate fluid seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia. Self-potential method was used to determine flow of water, and Ground magnetic method was used to find object that can influence the result of self potential measurement and the aquifer depth, the lines were spread 0m ≤ x ≤ 9m, 0m ≤ y ≤ 30m with a trace intervals of 1.5m and 0.75m per electrode spacing respectively. The result display by Self Potential signals gives a clear understand that water flow from higher value (central towards the lower value which is mostly at the southwest part than other areas and distinct level of feasible flow at different part ranges from -30mV to +35mV,which are very related to seepage flow patterns, negative SP anomalies were related with subsurface seepage flow paths (recharge zone and positive SP anomalies were related with areas of seepage outflow (discharge zone; and Ground Magnetic signals shows good details of the buried materials with high magnetic values which was interpreted as baked clay bricks and low magnetic values indicate groundwater seepage with depth of 5m. Therefore, the two results have correlation significant at 0.8 which show good correlation in groundwater investigation in this study, which validates the results.

  19. Environmental hazards from natural hydrocarbons seepage: Integrated classification of risk from sediment chemistry, bioavailability and biomarkers responses in sentinel species

    International Nuclear Information System (INIS)

    Benedetti, Maura; Gorbi, Stefania; Fattorini, Daniele; D'Errico, Giuseppe; Piva, Francesco; Pacitti, Davide; Regoli, Francesco

    2014-01-01

    Potential effects of natural emissions of hydrocarbons in the marine environment have been poorly investigated. In this study, a multidisciplinary weight of evidence (WOE) study was carried out on a shallow seepage, integrating sediment chemistry with bioavailability and onset of subcellular responses (biomarkers) in caged eels and mussels. Results from different lines of evidence (LOEs) were elaborated within a quantitative WOE model which, based on logical flowcharts, provide synthetic indices of hazard for each LOE, before their integration in a quantitative risk assessment. Evaluations of different LOEs were not always in accordance and their overall elaboration summarized as Moderate the risk in the seepage area. This study provided first evidence of biological effects in organisms exposed to natural hydrocarbon emissions, confirming the limit of chemical characterization as stand-alone criteria for environmental quality assessment and the utility of multidisciplinary investigations to determine the good environmental status as required by Environmental Directives. -- Highlights: • Hazards from natural seepage were evaluated through a multidisciplinary WOE study. • Caged eels and mussels were chosen as bioindicator organisms. • Evaluations obtained from various LOEs were not always in accordance. • Biological effects of natural hydrocarbons release were demonstrated. • WOE approach could discriminate different levels of hazard in low impacted conditions. -- A multidisciplinary WOE study in a shallow coastal seepage summarized a Moderate level of risk based on integration of sediment chemistry with biological effects in caged organisms

  20. Hydrogeology, geochemistry, and quality of water of The Basin and Oak Spring areas of the Chisos Mountains, Big Bend National Park, Texas

    Science.gov (United States)

    Baker, E.T.; Buszka, P.M.

    1993-01-01

    Test drilling near two sewage lagoons in The Basin area of the Chisos Mountains, Big Bend National Park, Texas, has shown that the alluvium and colluvium on which the lagoons are located is not saturated in the immediate vicinity of the lagoons. A shallow aquifer, therefore, does not exist in this critical area at and near the lagoons. Should seepage outflow from the lagoons occur, the effluent from the lagoons might eventually be incorporated into shallow ground water moving westward in the direction of Oak Spring. Under these conditions such water could reach the spring. Test borings that bottomed in bedrock below the alluvial and colluvial fill material are dry, indicating that no substantial leakage from the lagoons was detected. Therefore, no contaminant plume was identified. Fill material in The Basin does not contain water everywhere in its extensive outcropping area and supplies only a small quantity of ground water to Window Pouroff, which is the only natural surface outlet of The Basin.

  1. Unsteady free surface flow in porous media: One-dimensional model equations including vertical effects and seepage face

    Science.gov (United States)

    Di Nucci, Carmine

    2018-05-01

    This note examines the two-dimensional unsteady isothermal free surface flow of an incompressible fluid in a non-deformable, homogeneous, isotropic, and saturated porous medium (with zero recharge and neglecting capillary effects). Coupling a Boussinesq-type model for nonlinear water waves with Darcy's law, the two-dimensional flow problem is solved using one-dimensional model equations including vertical effects and seepage face. In order to take into account the seepage face development, the system equations (given by the continuity and momentum equations) are completed by an integral relation (deduced from the Cauchy theorem). After testing the model against data sets available in the literature, some numerical simulations, concerning the unsteady flow through a rectangular dam (with an impermeable horizontal bottom), are presented and discussed.

  2. Parameter Identification and Uncertainty Analysis for Visual MODFLOW based Groundwater Flow Model in a Small River Basin, Eastern India

    Science.gov (United States)

    Jena, S.

    2015-12-01

    The overexploitation of groundwater resulted in abandoning many shallow tube wells in the river Basin in Eastern India. For the sustainability of groundwater resources, basin-scale modelling of groundwater flow is essential for the efficient planning and management of the water resources. The main intent of this study is to develope a 3-D groundwater flow model of the study basin using the Visual MODFLOW package and successfully calibrate and validate it using 17 years of observed data. The sensitivity analysis was carried out to quantify the susceptibility of aquifer system to the river bank seepage, recharge from rainfall and agriculture practices, horizontal and vertical hydraulic conductivities, and specific yield. To quantify the impact of parameter uncertainties, Sequential Uncertainty Fitting Algorithm (SUFI-2) and Markov chain Monte Carlo (MCMC) techniques were implemented. Results from the two techniques were compared and the advantages and disadvantages were analysed. Nash-Sutcliffe coefficient (NSE) and coefficient of determination (R2) were adopted as two criteria during calibration and validation of the developed model. NSE and R2 values of groundwater flow model for calibration and validation periods were in acceptable range. Also, the MCMC technique was able to provide more reasonable results than SUFI-2. The calibrated and validated model will be useful to identify the aquifer properties, analyse the groundwater flow dynamics and the change in groundwater levels in future forecasts.

  3. Three-dimensional imaging, change detection, and stability assessment during the centerline trench levee seepage experiment using terrestrial light detection and ranging technology, Twitchell Island, California, 2012

    Science.gov (United States)

    Bawden, Gerald W.; Howle, James; Bond, Sandra; Shriro, Michelle; Buck, Peter

    2014-01-01

    A full scale field seepage test was conducted on a north-south trending levee segment of a now bypassed old meander belt on Twitchell Island, California, to understand the effects of live and decaying root systems on levee seepage and slope stability. The field test in May 2012 was centered on a north-south trench with two segments: a shorter control segment and a longer seepage test segment. The complete length of the trench area measured 40.4 meters (m) near the levee centerline with mature trees located on the waterside and landside of the levee flanks. The levee was instrumented with piezometers and tensiometers to measure positive and negative porewater pressures across the levee after the trench was flooded with water and held at a constant hydraulic head during the seepage test—the results from this component of the experiment are not discussed in this report. We collected more than one billion three-dimensional light detection and ranging (lidar) data points before, during, and after the centerline seepage test to assess centimeter-scale stability of the two trees and the levee crown. During the seepage test, the waterside tree toppled (rotated 20.7 degrees) into the water. The landside tree rotated away from the levee by 5 centimeters (cm) at a height of 2 m on the tree. The paved surface of the levee crown had three regions that showed subsidence on the waterside of the trench—discussed as the northern, central, and southern features. The northern feature is an elongate region that subsided 2.1 cm over an area with an average width of 1.35 m that extends 15.8 m parallel to the trench from the northern end of the trench to just north of the trench midpoint, and is associated with a crack 1 cm in height that formed during the seepage test on the trench wall. The central subsidence feature is a semicircular region on the waterside of the trench that subsided by as much as 6.2 cm over an area 3.4 m wide and 11.2 m long. The southern feature is an elongate

  4. Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

    International Nuclear Information System (INIS)

    Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

    1995-01-01

    A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

  5. RATE-DEPENDENT PULL-OUT BEARING CAPACITY OF PILES BY SIMILITUDE MODEL TESTS USING SEEPAGE FORCE

    Science.gov (United States)

    Kato, Tatsuya; Kokusho, Takaji

    Pull-out test of model piles was conducted by varying the pull-out velocity and skin friction of piles using a seepage force similitude model test apparatus. Due to the seepage consolidation under the pressure of 150kPa, the effective stress distribution in a prototype saturated soil of 17m could be successfully reproduced in the model ground of 28cm thick, in which the pull-out tests were carried out. The pull-out load rose to a peak value at small displacement, and then decreased to a residual value. At the same time, pore pressure in the vicinity of the pile decreased due to suction near the tip and the positive dilatancy near the pile skin. The maximum pull-out load, pile axial load, side friction and the corresponding displacement increased dramatically with increasing pull-out velocity. It was found that these rate-dependent trends become more prominent with increasing skin friction.

  6. Phase II Interim Report -- Assessment of Hydrocarbon Seepage Detection Methods on the Fort Peck Reservation, Northeast Montana

    Energy Technology Data Exchange (ETDEWEB)

    Monson, Lawrence M.

    2002-04-24

    The following work was performed: (1) collected reconnaissance micro-magnetic data and background field data for Area 1, (2) identified and collected soil sample data in three anomalous regions of Area 1, (3) sampled soils in Northwest Poplar Oil Field, (4) graphed, mapped, and interpreted all data areas listed above, (5) registered for the AAPG Penrose Conference on Hydrocarbon Seepage Mechanisms and Migration (postponed from 9/16/01 until 4/7/02 in Vancouver, B.C.). Results include the identification and confirmation of an oil and gas prospect in the northwest part of Area 1 and the verification of a potential shallow gas prospect in the West Poplar Area. Correlation of hydrocarbon micro-seepage to TM tonal anomalies needs further data analysis.

  7. Subduction zone earthquake probably triggered submarine hydrocarbon seepage offshore Pakistan

    Science.gov (United States)

    Fischer, David; José M., Mogollón; Michael, Strasser; Thomas, Pape; Gerhard, Bohrmann; Noemi, Fekete; Volkhard, Spiess; Sabine, Kasten

    2014-05-01

    Seepage of methane-dominated hydrocarbons is heterogeneous in space and time, and trigger mechanisms of episodic seep events are not well constrained. It is generally found that free hydrocarbon gas entering the local gas hydrate stability field in marine sediments is sequestered in gas hydrates. In this manner, gas hydrates can act as a buffer for carbon transport from the sediment into the ocean. However, the efficiency of gas hydrate-bearing sediments for retaining hydrocarbons may be corrupted: Hypothesized mechanisms include critical gas/fluid pressures beneath gas hydrate-bearing sediments, implying that these are susceptible to mechanical failure and subsequent gas release. Although gas hydrates often occur in seismically active regions, e.g., subduction zones, the role of earthquakes as potential triggers of hydrocarbon transport through gas hydrate-bearing sediments has hardly been explored. Based on a recent publication (Fischer et al., 2013), we present geochemical and transport/reaction-modelling data suggesting a substantial increase in upward gas flux and hydrocarbon emission into the water column following a major earthquake that occurred near the study sites in 1945. Calculating the formation time of authigenic barite enrichments identified in two sediment cores obtained from an anticlinal structure called "Nascent Ridge", we find they formed 38-91 years before sampling, which corresponds well to the time elapsed since the earthquake (62 years). Furthermore, applying a numerical model, we show that the local sulfate/methane transition zone shifted upward by several meters due to the increased methane flux and simulated sulfate profiles very closely match measured ones in a comparable time frame of 50-70 years. We thus propose a causal relation between the earthquake and the amplified gas flux and present reflection seismic data supporting our hypothesis that co-seismic ground shaking induced mechanical fracturing of gas hydrate-bearing sediments

  8. DRIFT-SCALE COUPLED PROCESSES (DST AND TH SEEPAGE) MODELS

    International Nuclear Information System (INIS)

    J.T. Birkholzer; S. Mukhopadhyay

    2005-01-01

    The purpose of this report is to document drift-scale modeling work performed to evaluate the thermal-hydrological (TH) behavior in Yucca Mountain fractured rock close to waste emplacement drifts. The heat generated by the decay of radioactive waste results in rock temperatures elevated from ambient for thousands of years after emplacement. Depending on the thermal load, these temperatures are high enough to cause boiling conditions in the rock, giving rise to water redistribution and altered flow paths. The predictive simulations described in this report are intended to investigate fluid flow in the vicinity of an emplacement drift for a range of thermal loads. Understanding the TH coupled processes is important for the performance of the repository because the thermally driven water saturation changes affect the potential seepage of water into waste emplacement drifts. Seepage of water is important because if enough water gets into the emplacement drifts and comes into contact with any exposed radionuclides, it may then be possible for the radionuclides to be transported out of the drifts and to the groundwater below the drifts. For above-boiling rock temperatures, vaporization of percolating water in the fractured rock overlying the repository can provide an important barrier capability that greatly reduces (and possibly eliminates) the potential of water seeping into the emplacement drifts. In addition to this thermal process, water is inhibited from entering the drift opening by capillary forces, which occur under both ambient and thermal conditions (capillary barrier). The combined barrier capability of vaporization processes and capillary forces in the near-field rock during the thermal period of the repository is analyzed and discussed in this report

  9. A new impulse-stage sand fracturing technology and its pilot application in the western Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Bin Qi

    2015-03-01

    Full Text Available A better placement of proppants has been always the goal pursued in sand fracturing in order to get longer effective fractures and higher flow conductivity. However, it is always difficult to achieve satisfactory effects by conventional processes. On the basis of theoretical analysis and simulation with FracproPT software, basic experiments, and innovative physical modeling experiment, a new impulse-stage fracturing process has been developed by combining a special pumping process with fiber, liquid and other auxiliary engineering means. Compared with conventional fracturing, the open seepage channel created by the new fracturing process has an obvious edge in effective fracture length and flow conductivity. Moreover, the open seepage channel can also improve fracture cleanliness and reduce pressure loss in artificial fractures, thus reaching the goal of prolonging the single-well production time and maximizing productivity. After the research on principles and optimal design of this new process, on-site pilot test and detailed post-fracturing evaluation were conducted. The results indicated that (1 the new process is highly operable and feasible; (2 compared with the adjacent wells with similar geological conditions, the proppant' cost is reduced by 44%–47%, the ratio of effective fracture length to propped fracture length is increased by about 16%, the fracturing fluid recovery rate is up to 63% after 18 h in the test, and the normalized production is 1.9–2.3 times that of the adjacent wells; and (3 the new process can significantly lower the cost and enhance production. The process has a broad application prospect in shallow-middle sand gas reservoirs and shale gas reservoirs in western Sichuan Basin.

  10. Electrical resistivity investigation of fluvial geomorphology to evaluate potential seepage conduits to agricultural lands along the San Joaquin River, Merced County, California, 2012–13

    Science.gov (United States)

    Groover, Krishangi D.; Burgess, Matthew K.; Howle, James F.; Phillips, Steven P.

    2017-02-08

    Increased flows in the San Joaquin River, part of the San Joaquin River Restoration Program, are designed to help restore fish populations. However, increased seepage losses could result from these higher restoration flows, which could exacerbate existing drainage problems in neighboring agricultural lands and potentially damage crops. Channel deposits of abandoned river meanders that are hydraulically connected to the river could act as seepage conduits, allowing rapid and widespread water-table rise during restoration flows. There is a need to identify the geometry and properties of these channel deposits to assess their role in potential increased seepage effects and to evaluate management alternatives for reducing seepage. Electrical and electromagnetic surface geophysical methods have provided a reliable proxy for lithology in studies of fluvial and hyporheic systems where a sufficient electrical contrast exists between deposits of differing grain size. In this study, direct-current (DC) resistivity was used to measure subsurface resistivity to identify channel deposits and to map their subsurface geometry. The efficacy of this method was assessed by using DC resistivity surveys collected along a reach of the San Joaquin River in Merced County, California, during the summers of 2012 and 2013, in conjunction with borings and associated measurements from a hydraulic profiling tool. Modeled DC resistivity data corresponded with data from cores, hand-auger samples, a hydraulic profiling tool, and aerial photographs, confirming that DC resistivity is effective for differentiating between silt and sand deposits in this setting. Modeled DC resistivity data provided detailed two-dimensional cross-sectional resistivity profiles to a depth of about 20 meters. The distribution of high-resistivity units in these profiles was used as a proxy for identifying areas of high hydraulic conductivity. These data were used subsequently to guide the location and depth of wells

  11. Lance water injection tests adjacent to the 281-3H retention basin at the Savannah River Site, Aiken, South Carolina

    International Nuclear Information System (INIS)

    Freifeld, B.; Myer, L.; Moridis, G.; Cook, P.; James, A.; Pellerin, L.; Pruess, K.

    1996-09-01

    A pilot-scale field demonstration of waste isolation using viscous- liquid containment barriers has been planned for the 281-3H retention basin at the Savannah River Site, Aiken, SC. The 281-3H basin is a shallow retention/seepage basin contaminated mainly by radionuclides. The viscous-liquid containment barrier utilizes the permeation of liquid grout to either entomb the contaminants within a monolithic grout structure or to isolate the waste by drastically reducing the permeability, of the soils around the plume. A clear understanding of the hydrogeologic setting of the retention basin is necessary for proper design of the viscous liquid barrier. To aid in the understanding of the hydrogeology of the 281-3H retention basin, and to obtain critical parameters necessary for grout injection design, a series of tests were undertaken in a region immediately adjacent to the basin. The objectives of the LWIT were: 1. To evaluate the general performance of the Lance Injection Technique for grout emplacement at the site, including the range and upper limits of injection pressures, the flow rates applicable for site conditions, as well as the mechanical forces needed for lance penetration. 2. To obtain detailed information on the injectability of the soils immediately adjacent to the H-area retention basin. 3. To identify any high permeability zones suitable for injection and evaluate their spatial distribution. 4. To perform ground penetrating radar (GPR) to gain information on the structure of the soil column and to compare the results with LWIT data. This report will focus on results pertinent to these objectives

  12. Control and prevention of seepage from uranium mill waste disposal facilities

    International Nuclear Information System (INIS)

    Williams, R.E.

    1978-01-01

    This paper constitutes an analysis of the technologies which are available for the prevention of movement of waste waters out of uranium mill waste disposal facilities via sub-surface routes. Hydrogeologic criteria for potential uranium mill waste disposal sites and mathematical modeling of contaminant migration in ground water are presented. Methods for prevention of seepage from uranium mill waste disposal facilities are investigated: liners, clay seals, synthetic polymeric membranes (PVC, polyethylene, chlorinated polyethylene, hypalon, butyl rubber, neoprene, elasticized polyolefin)

  13. Maternal Folate Status and the BHMT c.716G>A Polymorphism Affect the Betaine Dimethylglycine Pathway during Pregnancy

    Directory of Open Access Journals (Sweden)

    Jose M. Colomina

    2016-10-01

    Full Text Available The effect of the betaine: homocysteine methyltransferase BHMT c.716G>A (G: guanosine; A: adenosine single nucleotide polymorphism (SNP on the BHMT pathway is unknown during pregnancy. We hypothesised that it impairs betaine to dimethylglycine conversion and that folate status modifies its effect. We studied 612 women from the Reus Tarragona Birth Cohort from ≤12 gestational weeks (GW throughout pregnancy. The frequency of the variant BHMT c.716A allele was 30.8% (95% confidence interval (CI: 28.3, 33.5. In participants with normal-high plasma folate status (>13.4 nmol/L, least square geometric mean [95% CI] plasma dimethylglycine (pDMG, µmol/L was lower in the GA (2.35 [2.23, 2.47] versus GG (2.58 [2.46, 2.70] genotype at ≤12 GW (p < 0.05 and in the GA (2.08 [1.97, 2.19] and AA (1.94 [1.75, 2.16] versus GG (2.29 [2.18, 2.40] genotypes at 15 GW (p < 0.05. No differences in pDMG between genotypes were observed in participants with possible folate deficiency (≤13.4 nmol/L (p for interactions at ≤12 GW: 0.023 and 15 GW: 0.038. PDMG was lower in participants with the AA versus GG genotype at 34 GW (2.01 [1.79, 2.25] versus 2.44 [2.16, 2.76] and at labour, 2.51 [2.39, 2.64] versus 3.00 [2.84, 3.18], (p < 0.01. Possible deficiency compared to normal-high folate status was associated with higher pDMG in multiple linear regression analysis (β coefficients [SEM] ranging from 0.07 [0.04], p < 0.05 to 0.20 [0.04], p < 0.001 in models from early and mid-late pregnancy and the AA compared to GG genotype was associated with lower pDMG (β coefficients [SEM] ranging from −0.11 [0.06], p = 0.055 to −0.23 [0.06], p < 0.001. Conclusion: During pregnancy, the BHMT pathway is affected by folate status and by the variant BHMT c.716A allele.

  14. Phase II Interim Report - Assessment of Hydrocarbon Seepage Detection Methods on the Fort Peck Reservation, Northeast Montana; SEMIANNUAL

    International Nuclear Information System (INIS)

    Monson, Lawrence M.

    2002-01-01

    The following work was performed: (1) collected reconnaissance micro-magnetic data and background field data for Area 1, (2) identified and collected soil sample data in three anomalous regions of Area 1, (3) sampled soils in Northwest Poplar Oil Field, (4) graphed, mapped, and interpreted all data areas listed above, (5) registered for the AAPG Penrose Conference on Hydrocarbon Seepage Mechanisms and Migration (postponed from 9/16/01 until 4/7/02 in Vancouver, B.C.). Results include the identification and confirmation of an oil and gas prospect in the northwest part of Area 1 and the verification of a potential shallow gas prospect in the West Poplar Area. Correlation of hydrocarbon micro-seepage to TM tonal anomalies needs further data analysis

  15. Four Mile Creek semi-annual sampling report, January 1993 sampling event

    International Nuclear Information System (INIS)

    1993-05-01

    From 1955 to 1988 low-level radioactive wastewater generated by chemical separation processes within the General Separations Area (GSA) was discharged to seepage basins in the F and H Areas of the Savannah River Site (SRS). These basins were designed to permit the infiltration of the process wastewaters. As wastewater percolated downward through the basins, chemical and radioactive constituents were retained or sequestered in the subsoils. An extensive study aimed at characterizing the groundwater seeping into Four Mile Creek and its associated seepline was conducted in 1988 and 1989 (Haselow et al. 1990). Results of this study suggested that contaminants leaching from the F and H Area seepage basins were impacting the Four Mile Creek wetland system. The seepage basins were closed in 1988 and capped and sealed in 1990. This effectively eliminated the source of the contaminants and the hydraulic head driving the migration of contaminants from the basins. It has been hypothesized that, after the elimination of the source and head, annual rainfall amounts would be sufficient to dilute and flush out contaminants remaining in the subsoils and groundwaters beneath the basins. Westinghouse Savannah River Company has designed a semi-annual sampling and analytical program for the Four Mile Creek (FMC) seepline and stream water to test the hypothesis. This report summarizes field monitoring activities from January 25, 1993 to February 4, 1993

  16. Levee Seepage Detection in the Sacramento-San Joaquin Delta Using Polarimetric SAR

    Science.gov (United States)

    An, K.; Jones, C. E.; Bekaert, D. P.

    2017-12-01

    The Sacramento-San Joaquin Delta's extensive levee system protects over 2,800 km2 of reclaimed lands and serves as the main irrigation and domestic water supply for the state of California. However, ongoing subsidence and disaster threats from floods and earthquakes make the Delta levee system highly vulnerable, endangering water supplies for 23 million California residents and 2.5 million acres of agricultural land. Levee failure in the Delta can cause saltwater intrusion from San Francisco Bay, reducing water quality and curtailing water exports to residents, commercial users, and farmers. To protect the Delta levee system, it is essential to search for signs of seepage in which water is piping through or beneath levees, which can be associated with deformation of the levees themselves. Until now, in-situ monitoring has largely been applied, however, this is a time-consuming and expensive approach. We use data acquired with NASA's UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) airborne radar instrument to identify and characterize levee seepages and associated land subsidence through advanced remote sensing technologies. The high spatial resolution of UAVSAR can help to direct surveys to areas that are likely to be experiencing damage. UAVSAR is an L-band airborne sensor with high signal-to-noise ratio, repeat flight track accuracy, and spatial resolution of 7x7 m2 (for multi-looked products) that is necessary for detailed levee monitoring. The adaptability of radar instruments in their ability to see through smoke, haze, and clouds during the day or night, is especially relevant during disaster events, when cloud cover or lack of solar illumination inhibits traditional visual surveys of damage. We demonstrate the advantages of combining polarimetric radar imagery with geographic information systems (GIS) datasets in locating seepage features along critical levee infrastructure in the Delta for 2009-2016. The ability to efficiently locate potential

  17. Microbial Community Response to Simulated Petroleum Seepage in Caspian Sea Sediments

    Directory of Open Access Journals (Sweden)

    Katrin Knittel

    2017-04-01

    Full Text Available Anaerobic microbial hydrocarbon degradation is a major biogeochemical process at marine seeps. Here we studied the response of the microbial community to petroleum seepage simulated for 190 days in a sediment core from the Caspian Sea using a sediment-oil-flow-through (SOFT system. Untreated (without simulated petroleum seepage and SOFT sediment microbial communities shared 43% bacterial genus-level 16S rRNA-based operational taxonomic units (OTU0.945 but shared only 23% archaeal OTU0.945. The community differed significantly between sediment layers. The detection of fourfold higher deltaproteobacterial cell numbers in SOFT than in untreated sediment at depths characterized by highest sulfate reduction rates and strongest decrease of gaseous and mid-chain alkane concentrations indicated a specific response of hydrocarbon-degrading Deltaproteobacteria. Based on an increase in specific CARD-FISH cell numbers, we suggest the following groups of sulfate-reducing bacteria to be likely responsible for the observed decrease in aliphatic and aromatic hydrocarbon concentration in SOFT sediments: clade SCA1 for propane and butane degradation, clade LCA2 for mid- to long-chain alkane degradation, clade Cyhx for cycloalkanes, pentane and hexane degradation, and relatives of Desulfobacula for toluene degradation. Highest numbers of archaea of the genus Methanosarcina were found in the methanogenic zone of the SOFT core where we detected preferential degradation of long-chain hydrocarbons. Sequencing of masD, a marker gene for alkane degradation encoding (1-methylalkylsuccinate synthase, revealed a low diversity in SOFT sediment with two abundant species-level MasD OTU0.96.

  18. Succession of Hydrocarbon Degradation and Microbial Diversity during a Simulated Petroleum Seepage in Caspian Sea Sediments

    Science.gov (United States)

    Mishra, S.; Stagars, M.; Wefers, P.; Schmidt, M.; Knittel, K.; Krueger, M.; Leifer, I.; Treude, T.

    2016-02-01

    Microbial degradation of petroleum was investigated in intact sediment cores of Caspian Sea during a simulated petroleum seepage using a sediment-oil-flow-through (SOFT) system. Over the course of the SOFT experiment (190 days), distinct redox zones established and evolved in the sediment core. Methanogenesis and sulfate reduction were identified to be important processes in the anaerobic degradation of hydrocarbons. C1 to C6 n-alkanes were completely exhausted in the sulfate-reducing zone and some higher alkanes decreased during the upward migration of petroleum. A diversity of sulfate-reducing bacteria was identified by 16s rRNA phylogenetic studies, some of which are associated with marine seeps and petroleum degradation. The δ13C signal of produced methane decreased from -33.7‰ to -49.5‰ indicating crude oil degradation by methanogenesis, which was supported by enrichment culturing of methanogens with petroleum hydrocarbons and presence of methanogenic archaea. The SOFT system is, to the best of our knowledge, the first system that simulates an oil-seep like condition and enables live monitoring of biogeochemical changes within a sediment core during petroleum seepage. During our presentation we will compare the Caspian Sea data with other sediments we studied using the SOFT system from sites such as Santa Barbara (Pacific Ocean), the North Alex Mud Volcano (Mediterranean Sea) and the Eckernfoerde Bay (Baltic Sea). This research was funded by the Deutsche Forschungsgemeinschaft (SPP 1319) and DEA Deutsche Erdoel AG. Further support came from the Helmholtz and Max Planck Gesellschaft.

  19. Calibration and application of an automated seepage meter for monitoring water flow across the sediment-water interface.

    Science.gov (United States)

    Zhu, Tengyi; Fu, Dafang; Jenkinson, Byron; Jafvert, Chad T

    2015-04-01

    The advective flow of sediment pore water is an important parameter for understanding natural geochemical processes within lake, river, wetland, and marine sediments and also for properly designing permeable remedial sediment caps placed over contaminated sediments. Automated heat pulse seepage meters can be used to measure the vertical component of sediment pore water flow (i.e., vertical Darcy velocity); however, little information on meter calibration as a function of ambient water temperature exists in the literature. As a result, a method with associated equations for calibrating a heat pulse seepage meter as a function of ambient water temperature is fully described in this paper. Results of meter calibration over the temperature range 7.5 to 21.2 °C indicate that errors in accuracy are significant if proper temperature-dependence calibration is not performed. The proposed calibration method allows for temperature corrections to be made automatically in the field at any ambient water temperature. The significance of these corrections is discussed.

  20. Releases of radioactivity at the Savannah River Plant, 1954-1980

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, C.; Zeigler, C. C.; Culp, P. A.

    1982-01-01

    This report contains summaries of releases of radioactivity to onsite seepage basins and to plant effluents for each year since plant startup (1954 through 1980). Releases for the years 1954 through 1959 were reassessed in 1974 and assigned release values for specific long-lived radionuclides. These long-lived radionuclides (half-lives greater than 1 year) are the only radionuclides included for the years 1954 through 1970. Since 1970 all detectable radionuclides have been included. Measured migration o radionuclides from F-, H-, and K-Area seepage basins and desorption of /sup 137/Cs from the Four Mile Creek stream bed are included in Summary B of this report. Summaries of monthly releases for 1979 and 1980 and total SRP releases by radionuclide in three categories: liquid to seepage basins, liquid to streams, and atmospheric are also included. Monthly releases for 1979 are included because the 1979 issue of this report was not published. All 1979 data are included in this report.

  1. Effects of groundwater levels and headwater wetlands on streamflow in the Charlie Creek basin, Peace River watershed, west-central Florida

    Science.gov (United States)

    Lee, T.M.; Sacks, L.A.; Hughes, J.D.

    2010-01-01

    The Charlie Creek basin was studied from April 2004 to December 2005 to better understand how groundwater levels in the underlying aquifers and storage and overflow of water from headwater wetlands preserve the streamflows exiting this least-developed tributary basin of the Peace River watershed. The hydrogeologic framework, physical characteristics, and streamflow were described and quantified for five subbasins of the 330-square mile Charlie Creek basin, allowing the contribution of its headwaters area and tributary subbasins to be separately quantified. A MIKE SHE model simulation of the integrated surface-water and groundwater flow processes in the basin was used to simulate daily streamflow observed over 21 months in 2004 and 2005 at five streamflow stations, and to quantify the monthly and annual water budgets for the five subbasins including the changing amount of water stored in wetlands. Groundwater heads were mapped in Zone 2 of the intermediate aquifer system and in the Upper Floridan aquifer, and were used to interpret the location of artesian head conditions in the Charlie Creek basin and its relation to streamflow. Artesian conditions in the intermediate aquifer system induce upward groundwater flow into the surficial aquifer and help sustain base flow which supplies about two-thirds of the streamflow from the Charlie Creek basin. Seepage measurements confirmed seepage inflow to Charlie Creek during the study period. The upper half of the basin, comprised largely of the Upper Charlie Creek subbasin, has lower runoff potential than the lower basin, more storage of runoff in wetlands, and periodically generates no streamflow. Artesian head conditions in the intermediate aquifer system were widespread in the upper half of the Charlie Creek basin, preventing downward leakage from expansive areas of wetlands and enabling them to act as headwaters to Charlie Creek once their storage requirements were met. Currently, the dynamic balance between wetland

  2. Seepage safety monitoring model for an earth rock dam under influence of high-impact typhoons based on particle swarm optimization algorithm

    Directory of Open Access Journals (Sweden)

    Yan Xiang

    2017-01-01

    Full Text Available Extreme hydrological events induced by typhoons in reservoir areas have presented severe challenges to the safe operation of hydraulic structures. Based on analysis of the seepage characteristics of an earth rock dam, a novel seepage safety monitoring model was constructed in this study. The nonlinear influence processes of the antecedent reservoir water level and rainfall were assumed to follow normal distributions. The particle swarm optimization (PSO algorithm was used to optimize the model parameters so as to raise the fitting accuracy. In addition, a mutation factor was introduced to simulate the sudden increase in the piezometric level induced by short-duration heavy rainfall and the possible historical extreme reservoir water level during a typhoon. In order to verify the efficacy of this model, the earth rock dam of the Siminghu Reservoir was used as an example. The piezometric level at the SW1-2 measuring point during Typhoon Fitow in 2013 was fitted with the present model, and a corresponding theoretical expression was established. Comparison of fitting results of the piezometric level obtained from the present statistical model and traditional statistical model with monitored values during the typhoon shows that the present model has a higher fitting accuracy and can simulate the uprush feature of the seepage pressure during the typhoon perfectly.

  3. Seepage Analysis of Upper Gotvand Dam Concerning Gypsum Karstification (2D and 3D Approaches)

    DEFF Research Database (Denmark)

    Sadrekarimi, Jamshid; Kiyani, Majid; Fakhri, Behnam

    2011-01-01

    Upper Gotvand Dam is constructed on the Karun River at the south west of Iran. In this paper, 2D and 3D models of the dam together with the foundation and abutments were established, and several seepage analyses were carried out. Then, the gypsum veins that are scattered throughout the foundation...

  4. Identification of the glaciers and mountain naturally dammed lakes in the Pskem, the Kashkadarya and the Surhandarya River basins, Uzbekistan, using ALOS satellite data

    Directory of Open Access Journals (Sweden)

    Eleonora Semakova

    2016-05-01

    Full Text Available The glacierized area of Uzbekistan is represented in three river basins – the Pskem, the Kashkadarya and the Surhandarya. This study considers the present state of the glaciers and high-mountain lakes distribution in this area based on the analysis and validation of advanced land observing satellite (ALOS/advanced visible and near infrared radiometer type 2 (AVNIR-2 satellite data. Between the 1960s and the 2010s, the glacierized area decreased by 23% in the Pskem River basin (including the Maydantal, by 49% in the Kashkadarya and by 40% in the Surhandarya (including the Sangardak and the Tupalang River basins. The retreat fairly slowed in the 1980s–2010s. There are 75 glacial lakes and 35 rock-dammed lakes (including landslide-dammed ones in the Pskem River basin, 45% of all the lakes covering the area less than 0.002 km2; 13 glacial lakes and 4 rock-dammed lakes in the Kashkadarya and 34 glacial lakes and 16 rock-dammed lakes in the Surhandarya River basins. The landslide rock-dammed Ikhnach Upper Lake lost 0.04 km2 in size from 1 August 2010 to 30 August 2010 because of the seepage through the rock dam and 0.10 km2 from 1 August to 18 October 2013.

  5. Changes in contaminant composition at landfill sites. (9). ; Application of soil covering to treatment of alkaline seepage water. Umetate ni okeru odaku seibun no doko. (9). ; Alkali sei shinsutsueki no gaido shori

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Y; Sugai, T; Masuda, T; Watanabe, Y; Kobayashi, S [Saitama Institute of Environmental Pollution, Saitama (Japan)

    1990-10-29

    Recently, alkaline seepage water has been found in many landfill sites. Strong alkaline seepage water results from the use of alkaline agents, such as quicklime and slaked lime, for water removal from waste. In the present report, the neutralizing ability of different types of soil is studied to provide a method to neutralize seepage water by using soil covering at landfill sites. Results show that clay contained in soil is playing a major role in neutralizing alkaline seepage penetrating the soil. Clay generally has negative electric charges, suggesting that positive ions in alkaline water is neutralized after being replaced by hydrogen ions. Another major factor is the carbonate ion and carbon dioxide existing in soil, which precipitate and solidify calcium hydroxide as calcium carbonate to achieve neutralization. Investigations indicate that top soil comprising volcanic ash is useful as material for soil covering. 2 figs., 5 tabs.

  6. Uncertainty of the Soil–Water Characteristic Curve and Its Effects on Slope Seepage and Stability Analysis under Conditions of Rainfall Using the Markov Chain Monte Carlo Method

    Directory of Open Access Journals (Sweden)

    Weiping Liu

    2017-10-01

    Full Text Available It is important to determine the soil–water characteristic curve (SWCC for analyzing slope seepage and stability under the conditions of rainfall. However, SWCCs exhibit high uncertainty because of complex influencing factors, which has not been previously considered in slope seepage and stability analysis under conditions of rainfall. This study aimed to evaluate the uncertainty of the SWCC and its effects on the seepage and stability analysis of an unsaturated soil slope under conditions of rainfall. The SWCC model parameters were treated as random variables. An uncertainty evaluation of the parameters was conducted based on the Bayesian approach and the Markov chain Monte Carlo (MCMC method. Observed data from granite residual soil were used to test the uncertainty of the SWCC. Then, different confidence intervals for the model parameters of the SWCC were constructed. The slope seepage and stability analysis under conditions of rainfall with the SWCC of different confidence intervals was investigated using finite element software (SEEP/W and SLOPE/W. The results demonstrated that SWCC uncertainty had significant effects on slope seepage and stability. In general, the larger the percentile value, the greater the reduction of negative pore-water pressure in the soil layer and the lower the safety factor of the slope. Uncertainties in the model parameters of the SWCC can lead to obvious errors in predicted pore-water pressure profiles and the estimated safety factor of the slope under conditions of rainfall.

  7. Leakage and Seepage of CO2 from Geologic Carbon Sequestration Sites: CO2 Migration into Surface Water

    International Nuclear Information System (INIS)

    Oldenburg, Curt M.; Lewicki, Jennifer L.

    2005-01-01

    Geologic carbon sequestration is the capture of anthropogenic carbon dioxide (CO 2 ) and its storage in deep geologic formations. One of the concerns of geologic carbon sequestration is that injected CO 2 may leak out of the intended storage formation, migrate to the near-surface environment, and seep out of the ground or into surface water. In this research, we investigate the process of CO 2 leakage and seepage into saturated sediments and overlying surface water bodies such as rivers, lakes, wetlands, and continental shelf marine environments. Natural CO 2 and CH 4 fluxes are well studied and provide insight into the expected transport mechanisms and fate of seepage fluxes of similar magnitude. Also, natural CO 2 and CH 4 fluxes are pervasive in surface water environments at levels that may mask low-level carbon sequestration leakage and seepage. Extreme examples are the well known volcanic lakes in Cameroon where lake water supersaturated with respect to CO 2 overturned and degassed with lethal effects. Standard bubble formation and hydrostatics are applicable to CO 2 bubbles in surface water. Bubble-rise velocity in surface water is a function of bubble size and reaches a maximum of approximately 30 cm s -1 at a bubble radius of 0.7 mm. Bubble rise in saturated porous media below surface water is affected by surface tension and buoyancy forces, along with the solid matrix pore structure. For medium and fine grain sizes, surface tension forces dominate and gas transport tends to occur as channel flow rather than bubble flow. For coarse porous media such as gravels and coarse sand, buoyancy dominates and the maximum bubble rise velocity is predicted to be approximately 18 cm s -1 . Liquid CO 2 bubbles rise slower in water than gaseous CO 2 bubbles due to the smaller density contrast. A comparison of ebullition (i.e., bubble formation) and resulting bubble flow versus dispersive gas transport for CO 2 and CH 4 at three different seepage rates reveals that

  8. Characterization of salinity loads and selenium loads in the Smith Fork Creek region of the Lower Gunnison River Basin, western Colorado, 2008-2009

    Science.gov (United States)

    Richards, Rodney J.; Linard, Joshua I.; Hobza, Christopher M.

    2014-01-01

    The lower Gunnison River Basin of the Colorado River Basin has elevated salinity and selenium levels. The Colorado River Basin Salinity Control Act of June 24, 1974 (Public Law 93–320, amended by Public Law 98–569), authorized investigation of the Lower Gunnison Basin Unit Salinity Control Project by the U.S. Department of the Interior. The Bureau of Reclamation (Reclamation) and the Natural Resources Conservation Service are responsible for assessing and implementing measures to reduce salinity and selenium loading in the Colorado River Basin. Cost-sharing programs help farmers, ranchers, and canal companies improve the efficiency of water delivery systems and irrigation practices. The delivery systems (irrigation canals) have been identified as potential sources of seepage, which can contribute to salinity loading. Reclamation wants to identify seepage from irrigation systems in order to maximize the effectiveness of the various salinity-control methods, such as polyacrylamide lining and piping of irrigation canals programs. The U.S. Geological Survey, in cooperation with Reclamation, developed a study to characterize the salinity and selenium loading of seven subbasins in the Smith Fork Creek region and identify where control efforts can be maximized to reduce salinity and selenium loading. Total salinity loads ranged from 27.9±19.1 tons per year (t/yr) to 87,500±80,500 t/yr. The four natural subbasins—BkKm, RCG1, RCG2, and SF1—had total salinity loads of 27.9±19.1 t/yr, 371±248 t/yr, 2,180±1,590 t/yr, and 4,200±2,720 t/yr, respectively. The agriculturally influenced sites had salinity loads that ranged from 7,580±6,900 t/yr to 87,500±80,500 t/yr. Salinity loads for the subbasins AL1, B1, CK1, SF2, and SF3 were 7,580±6,900 t/yr; 28,300±26,700 t/yr; 48,700±36,100 t/yr; 87,500±80,900 t/yr; and 52,200±31,800 t/yr, respectively. The agricultural salinity load was separated into three components: tail water, deep percolation, and canal seepage

  9. Releases of radioactivity at the Savannah River Plant, 1954--1985

    International Nuclear Information System (INIS)

    Zeigler, C.C.; Lawrimore, I.B.

    1988-07-01

    Radioactive releases from Savannah River Plant (SRP) facilities to air, water and earthen seepage basins have been monitored and tabulated throughout the history of the site. The purpose of this report is to provide a source of data on routine releases of radioactivity to air, water and seepage basins that can be used for analyses of trends, environmental impact, etc. As used in this report, routine radioactive releases means radioactive materials that are released through established effluents from process facilities. This report provides a summary of radioactive releases that inflects the release values contained m records and documents from startup through 1985

  10. Removal and co-transport of Zn, As(V), and Cd during leachate seepage through downgradient mine soils: A batch sorption and column study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Juhee [Division of Environmental Science and Ecological Engineering, Korea University, Seoul (Korea, Republic of); Nam, Seung Mo [Korea Testing and Research Institute, Gyeonggi-do (Korea, Republic of); Hyun, Seunghun, E-mail: soilhyun@korea.ac.kr [Division of Environmental Science and Ecological Engineering, Korea University, Seoul (Korea, Republic of)

    2016-05-01

    The removal of Zn, As(V), and Cd during the leachate seepage process was measured in single, binary, and ternary solute systems by batch sorption and 1-D column flow experiments, followed by a sequential extraction procedure (SEP). In single-solute systems, sorption (K{sub d}{sup ⁎}) occurred in the order of As(V) > Zn ≫ Cd, and this sequence did not change in the presence of other solutes. In multi-solute systems, the sorption of Zn (~ 20%) and Cd (~ 27%) was enhanced by As(V), while Zn and Cd suppressed the sorption of each other. In all cases, As(V) sorption was not affected by the cations, indicating that As(V) is prioritized by sorption sites to a much greater degree than Zn and Cd. Element retention by column soils was strongly correlated (r{sup 2} = 0.77) with K{sub d}{sup ⁎}. Across column segments, mass retention was in the order of inlet (36–54%) > middle (26–35%) > outlet (20–31%), except for Cd in the Zn–Cd binary system. The result of SEP revealed that most of the retained Cd (98–99%) and Zn (56–71%) was in the labile fraction (e.g., the sum of F1 and F2) while only 9–12% of As(V) was labile and most (> 55%) was specifically adsorbed to Fe/Al oxides. Plots of the labile fraction (f{sub labile}) and the fast sorption fraction (f{sub fast}) suggested that the kinetics of specific As(V) sorption occur rapidly (f{sub fast} > f{sub labile}), whereas labile Zn and Cd sorption occurs slowly (f{sub labile} > f{sub fast}), indicating the occurrence of kinetically limited labile sorption sites, probably due to Zn–Cd competition. In conclusion, the element leaching potential of mine leachate can be greatly attenuated during downgradient soil seepage. However, when assessing the soil attenuation process, the impact of sorption competitors and the lability of adsorbed elements should first be considered. - Highlights: • During soil seepage, element leaching potential is reduced as As(V) > Zn > Cd. • Element removal during leachate seepage

  11. Polymer flooding effect of seepage characteristics of the second tertiary combined model of L oilfield block B

    Directory of Open Access Journals (Sweden)

    Huan ZHAO

    2015-06-01

    Full Text Available The second tertiary combined model is applied to develop the second and third type reservoirs which have more oil layer quantity and strong anisotropism, compared to the regular main reservoir with polymer injection, whose seepage characteristics of polymer-injection-after-water-drive shows a remarkable difference, in addition. This development appears to have a larger effect on the remaining oil development and production. Simulating the second tertiary combined model by reservoir numerical simulation under different polymer molecular weight, polymer concentration, polymer injection rate on the polymer injection period, conclusions of the influenced seepage characteristics of original and added perforated interval pressure and water saturation are drawn. The conclusion shows that the polymer molecular weight could influence water saturation of added perforated interval; polymer concentration makes a significant impact on reservoir pressure; polymer injection rate has a great influence on the separate rate of original and added perforated interval. This research provides firm science evidence to the theory of the second tertiary combined model to develop and enhance oil injection-production rate.

  12. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    Energy Technology Data Exchange (ETDEWEB)

    E. Gonnenthal; N. Spyoher

    2001-02-05

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) 2000 [153447]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M and O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: (1) Performance Assessment (PA); (2) Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); (3) UZ Flow and Transport Process Model Report (PMR); and (4) Near-Field Environment (NFE) PMR. The work scope for this activity is presented in the TWPs cited above, and summarized as follows: continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data

  13. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    International Nuclear Information System (INIS)

    Sonnenthale, E.

    2001-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) 2000 [1534471]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M and O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: Performance Assessment (PA); Near-Field Environment (NFE) PMR; Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); and UZ Flow and Transport Process Model Report (PMR). The work scope for this activity is presented in the TWPs cited above, and summarized as follows: Continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data, sensitivity and validation studies described in this AMR are

  14. Groundwater Seepage Estimation into Amirkabir Tunnel Using Analytical Methods and DEM and SGR Method

    OpenAIRE

    Hadi Farhadian; Homayoon Katibeh

    2015-01-01

    In this paper, groundwater seepage into Amirkabir tunnel has been estimated using analytical and numerical methods for 14 different sections of the tunnel. Site Groundwater Rating (SGR) method also has been performed for qualitative and quantitative classification of the tunnel sections. The obtained results of above mentioned methods were compared together. The study shows reasonable accordance with results of the all methods unless for two sections of tunnel. In these t...

  15. Study on of Seepage Flow Velocity in Sand Layer Profile as Affected by Water Depth and Slope Gradience

    Science.gov (United States)

    Han, Z.; Chen, X.

    2017-12-01

    BACKGROUND: The subsurface water flow velocity is of great significance in understanding the hydrodynamic characteristics of soil seepage and the influence of interaction between seepage flow and surface runoff on the soil erosion and sediment transport process. OBJECTIVE: To propose a visualized method and equipment for determining the seepage flow velocity and measuring the actual flow velocity and Darcy velocity as well as the relationship between them.METHOD: A transparent organic glass tank is used as the test soil tank, the white river sand is used as the seepage test material and the fluorescent dye is used as the indicator for tracing water flow, so as to determine the thickness and velocity of water flow in a visualized way. Water is supplied at the same flow rate (0.84 L h-1) to the three parts with an interval of 1m at the bottom of the soil tank and the pore water velocity and the thickness of each water layer are determined under four gradient conditions. The Darcy velocity of each layer is calculated according to the water supply flow and the discharge section area. The effective discharge flow pore is estimated according to the moisture content and porosity and then the relationship between Darcy velocity and the measured velocity is calculated based on the water supply flow and the water layer thickness, and finally the correctness of the calculation results is verified. RESULTS: According to the velocity calculation results, Darcy velocity increases significantly with the increase of gradient; in the sand layer profile, the flow velocity of pore water at different depths increases with the increase of gradient; under the condition of the same gradient, the lower sand layer has the maximum flow velocity of pore water. The air-filled porosity of sand layer determines the proportional relationship between Darcy velocity and pore flow velocity. CONCLUSIONS: The actual flow velocity and Darcy velocity can be measured by a visualized method and the

  16. Evaluation of ground-water flow and hydrologic budget for Lake Five-O, a seepage lake in northwestern Florida

    Science.gov (United States)

    Grubbs, J.W.

    1995-01-01

    Temporal and spatial distributions of ground-water inflow to, and leakage from Lake Five-O, a softwater, seepage lake in northwestern Florida, were evaluated using hydrologic data and simulation models of the shallow ground-water system adjacent to the lake. The simulation models indicate that ground-water inflow to the lake and leakage from the lake to the ground-water system are the dominant components in the total inflow (precipitation plus ground-water inflow) and total outflow (evaporation plus leakage) budgets of Lake Five-O. Simlulated ground-water inflow and leakage were approximately 4 and 5 times larger than precipitation inputs and evaporative losses, respectively, during calendar years 1989-90. Exchanges of water between Lake Five-O and the ground-water system were consistently larger than atmospheric-lake exchanges. A consistent pattern of shallow ground-water inflow and deep leakage was also evident throughout the study period. The mean time of travel from ground-water that discharges at Lake Five-O (time from recharge at the water table to discharge at the lake) was estimated to be within a range of 3 to 6 years. Flow-path evaluations indicated that the intermediate confining unit probably has a negligible influence on the geochemistry of ground-water inflow to Lake Five-O. The hydrologic budgets and flow-path evaluations provide critical information for developing geochemical budgets for Lake Five-O and for improving the understanding of the relative importance of various processes that regulate the acid-neutralizing capacity of softwater seepage lakes in Florida.

  17. Measuring and modelling salt and heat transport in low-land drainage canals : Flow and stratification effects of saline seepage

    NARCIS (Netherlands)

    Hilgersom, K.P.

    2017-01-01

    This thesis explores a new measuring approach to quantify the seepage flux from boils. Boils are preferential groundwater seeps and are a consequence of the groundwater flow that works its way through the soil matrix by creating vents of higher conductive material. In the Netherlands, boils often

  18. Potential for ground-water contamination from movement of wastewater through the unsaturated zone, upper Mojave River Basin, California

    Science.gov (United States)

    Umari, A.M.; Martin, P.M.; Schroeder, R.A.; Duell, L.F.; Fay, R.G.

    1993-01-01

    Septic-tank wastewater disposed in 30-foot-deep seepage pits (dry wells) at 46,000 residences is estimated to equal 18 percent of the natural recharge to the sole-source aquifer in the rapidly developing upper Mojave River Basin (Victor Valley) in the high desert northeast of Los Angeles. Vertical rates of movement of the wastewater wetting front through the unsaturated zone at three newly occupied residences ranged from 0.07 to 1.0 foot per day. These rates translate to traveltimes of several months to several years for the wastewater wetting front to reach the water table and imply that wastewater from many disposal systems already has reached the water table, which averages about 150 feet below land surface in the Victor Valley. As wastewater percolates from seepage pits into the adjacent unsaturated zone, the nitrogen present in reduced form is rapidly converted to nitrate. Analyses on soil-core extracts and soil moisturefrom suction lysimeters installed beneath the seepage pits at eight residences showed that nitrate concentrations and nitrate/ chloride ratios generally become lower with increasing depth. The intervals of greatest decline seemed to coincide with finer soil texture or were near the water table. Nitrate-reducing bacteria were tested for and found to be present in soil cores from two residences. Sparse nitrogen-15 data from suction lysimeters at one of these residences, where thenitrate concentration decreased by about one-half at a depth of 200 feet, indicate that the nitrate decline was accompanied by nitrogen-15 enrichment in the residual nitrate with an isotope-separation factor of about -10 permil. Despite the potential input of abundant nitrogen with the domestic wastewater recharge, nitrate concentrations in the area's ground water are generally low. The absence of high nitrate concentrations in the ground water is consistent with the existence of denitrification, a microbial nitrogen-removal mechanism, as wastewater moves through the

  19. Plant community development within the F- and H-Area tree-kill zone

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, E.A.; Westbury, H.M. Jr.

    1994-10-01

    The F- and H-Area Seepage Basins received liquid waste from the F and H chemical separation facilities from 1955 through 1988. Tree mortality in seepline fed wetlands down-slope from the basins was observed in the late 1970`s, and investigations were conducted to determine the cause and source of the impacts. Analysis of the soil and water in the tree-kill zones demonstrated a strong chemical linkage with the F- and H-Area seepage basins. Although no single cause of the mortality was determined, it was believed to be the result of interactions of alterations in the hydrology and erosional deposition, along with lowering of pH and increased conductivity, sodium, aluminum, and nitrogen compounds. A mild drought during the growing season may also have increased the concentration of the chemical contaminants in the soils matrix. In 1988, the F- and H-Area Seepage Basins were closed and covered with a clay cap to reduce the rate of dispersion of the contaminants in the soil beneath the basins. Subsequent studies of the chemical composition of the tree-kill zone groundwater and toxicological characteristics of the seepline soil have shown a reduced contaminant flux. In 1993, an initial vegetation study was undertaken to determine the level of recovery by the plant communities in the tree-kill zones. This study repeats the initial vegetation investigation in order to further analyze and characterize the recovery of plant communities in the zones after an additional year of growth.

  20. STUDY OF GAS POTENCY BASED ON GRAVITY ANOMALY MODELING AND SEISMIC PROFILE ANALYSIS AT BANGGAI-SULA BASIN

    Directory of Open Access Journals (Sweden)

    Ediar Usman

    2017-07-01

    Full Text Available Banggai-Sula Basin is one of the basins with character of the micro-continent derived from northern part of Australia. Some traces the migration in the central part of Papua are slate, schist, and gneiss, current movement is facilitated by the Sorong Fault, which runs from the northern part of Papua to eastern part of Sulawesi. Results of gravity anomaly model (2D and 3D, seepage distribution, seismic and fields existing of oil and gas production in the western part of the Banggai-Sula Basin obtained a new prospect area in the northern part of Peleng Island, western part of Banggai Island, southern part of Banggai-Taliabu Islands, western and eastern part of Sulabesi Island. The new prospect area is reflected in the centre with form of the low morphology on gravity model and prospect trap on seismic data in the western part of Tolo Bay. Results of chemical analysis on the source rock of Buya Formation on Tmax vs Hydrogen Index (Tmax vs HI Diagram shows the type III kerogen quality and the Oxygen Index vs Hydrogen Index (OI vs HI Diagram shows the gas prone Type II, so that giving the impression that this area has the potential to containing the gas. The quality of the gas is included in the category of immature to mature type.

  1. Simulation of 2-dimensional subsurface seepage flow in an anisotropic porous medium

    Directory of Open Access Journals (Sweden)

    Chhaya K. Lande

    2016-09-01

    Full Text Available In this study, we develop new analytical solution to estimate the transient behavior of phreatic surface in an anisotropic unconfined aquifer which is overlying a leaky base and subjected to multiple recharge and withdrawal. The hydrologic setting consists of a rectangular unconfined leaky aquifer adjacent to two water bodies of constant water head along the opposite faces of the aquifer. The remaining two faces of the aquifer have no flow conditions. The flow of seepage is approximated using two-dimensional Boussinesq equation, and solved analytically using mixed finite Fourier transform. Application of the new solution is demonstrated using an illustrative example.

  2. Semi-annual sampling of Fourmile Branch and its seeplines in the F and H Areas of SRS: February 1993, July 1993, and April 1994. Revision 1

    International Nuclear Information System (INIS)

    Koch, J.W. II; Rogers, V.A.; Chappell, R.W.; Winslow, F.P.; Dixon, K.L.

    1995-01-01

    In February 1993, July 1993, and April 1994, water samples were collected from Fourmile Branch (FMB) and it seeplines in the vicinity of the F- and H-Area Seepage Basins. The three sampling events represent a continuation of a series of semi-annual sampling events aimed at characterizing the shallow groundwater outcropping into FMB and its wetlands. In the past, this groundwater has been shown to contain contaminants migrating from the F- and H-Area Seepage Basins. The samples were analyzed for metals listed in Title 40, Code of Federal Regulations (CRF), Part 264, Appendix IX, various radionuclides, selected volatile organic compounds, and selected inorganic constituents and parameters

  3. Laboratory Experiments on Steady State Seepage-Induced Landslides Using Slope Models and Sensors

    Directory of Open Access Journals (Sweden)

    Sandra G. Catane

    2011-06-01

    Full Text Available A thorough understanding of the failure initiation process is crucial in the development of physicallybased early warning system for landslides and slope failures. Laboratory-scale slope models were constructed and subjected to instability through simulated groundwater infiltration. This is done by progressively increasing the water level in the upslope tank and allowing water to infiltrate laterally towards the toe of the slope. Physical changes in the slope models were recorded by tilt sensors and video cameras. When the model slope was destabilized, the chronology of events occurred in the following sequence: (1 bulging at the toe, (2 seepage at the toe, (3 initial failure of soil mass, (4 piping, (5 retrogressive failure, (6 formation of tension cracks and (7 major failure of soil mass. Tension cracks, piping and eventual failure are manifestations of differential settlements due to variations in void ratio. Finite element analysis indicates that instability and subsequent failures in the model slope were induced primarily by high hydraulic gradients in the toe area. Seepage, initial deformation and subsequent failures were manifested in the toe area prior to failure, providing a maximum of 36 min lead time. Similar lead times are expected in slopes of the same material as shown in many case studies of dam failure. The potential of having a longer lead time is high for natural slopes made of materials with higher shear strength thus evacuation is possible. The tilt sensors were able to detect the initial changes before visual changes manifested, indicating the importance of instrumental monitoring.

  4. A geochemical study on mud volcanoes in the Junggar Basin, China

    Energy Technology Data Exchange (ETDEWEB)

    Nakada, Ryoichi, E-mail: ryo-nakada@hiroshima-u.ac.jp [Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Takahashi, Yoshio [Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Tsunogai, Urumu [Division of Earth and Planetary Sciences, Graduate School of Science, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo 060-0810 (Japan); Zheng Guodong [Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, 382 West Donggang Road, Lanzhou 730000 (China); Shimizu, Hiroshi [Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Hattori, Keiko H. [Department of Earth Science, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada)

    2011-07-15

    Highlights: > Gases released from Xinjiang mud volcanoes are dominated by thermogenic origin. > Secondary microbial activities occurring closer to the surface dramatically changed the {delta}{sup 13}C{sub CO2}. > The water-rock interaction occurred at deeper level than gas and petroleum reservoir. - Abstract: A comprehensive study was performed to characterize, for the first time, the mud, water, and gases released from onshore mud volcanoes located in the southern margin of the Junggar Basin, northwestern China. Chemical compositions of mud, along with the geology of the basin, suggest that a source of the mud is Mesozoic or Cenozoic shale. Oxygen and H isotope compositions of the released water suggest a local meteoric origin. Combined with the positive Eu anomalies of the water, a large {sup 18}O shift of the water suggests extensive interaction with rocks. Gases discharged from the mud volcanoes are predominantly thermogenic hydrocarbons, and the high {delta}{sup 13}C values (>+20 per mille VPDB) for CO{sub 2} gases and dissolved carbonate in muddy water suggest secondary methanogenesis with CO{sub 2} reduction after oil biodegradation. The enrichments of Eu and {sup 18}O in water and the low thermal gradient of the area suggest that the water-rock interactions possibly occur deeper than 3670 {+-} 200 m. On the other hand, considering the relationship to the petroleum reservoir around the mud volcanoes, the depth of the gases can be derived from about 3600 m, a depth that is greater than that generally estimated for reservoirs whose gas is characterized by {sup 13}C-enriched CO{sub 2}. Oil biodegradation with CO{sub 2} reduction likely occurs at a shallower depth along the seepage system of the mud volcano. The results contribute to the worldwide data set of gas genesis in mud volcanoes. Moreover, they further support the concept that most terrestrial mud volcanoes release thermogenic gas produced in very deep sediments and may be early indicators of oil

  5. Vertical migration of fine-grained sediments from interior to surface of seabed driven by seepage flows-`sub-bottom sediment pump action'

    Science.gov (United States)

    Zhang, Shaotong; Jia, Yonggang; Wen, Mingzheng; Wang, Zhenhao; Zhang, Yaqi; Zhu, Chaoqi; Li, Bowen; Liu, Xiaolei

    2017-02-01

    A scientific hypothesis is proposed and preliminarily verified in this paper: under the driving of seepage flows, there might be a vertical migration of fine-grained soil particles from interior to surface of seabed, which is defined as `sub-bottom sediment pump action' in this paper. Field experiments were performed twice on the intertidal flat of the Yellow River delta to study this process via both trapping the pumped materials and recording the pore pressures in the substrate. Experimental results are quite interesting as we did observe yellow slurry which is mainly composed of fine-grained soil particles appearing on the seabed surface; seepage gradients were also detected in the intertidal flat, under the action of tides and small wind waves. Preliminary conclusions are that `sediment pump' occurs when seepage force exceeds a certain threshold: firstly, it is big enough to disconnect the soil particles from the soil skeleton; secondly, the degree of seabed fluidization or bioturbation is big enough to provide preferred paths for the detached materials to migrate upwards. Then they would be firstly pumped from interior to the surface of seabed and then easily re-suspended into overlying water column. Influential factors of `sediment pump' are determined as hydrodynamics (wave energy), degree of consolidation, index of bioturbation (permeability) and content of fine-grained materials (sedimentary age). This new perspective of `sediment pump' may provide some implications for the mechanism interpretation of several unclear geological phenomena in the Yellow River delta area.

  6. Iron speciation and mineral characterization of upper Jurassic reservoir rocks in the Minhe Basin, NW China

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiangxian; Zheng, Guodong, E-mail: gdzhbj@mail.iggcas.ac.cn; Xu, Wang [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Liang, Minliang [Chinese Academy of Geological Sciences, Institute of Geomechanics, Key Lab of Shale Oil and Gas Geological Survey (China); Fan, Qiaohui; Wu, Yingzhong; Ye, Conglin [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Shozugawa, Katsumi; Matsuo, Motoyuki [The University of Tokyo, Graduate School of Arts and Sciences (Japan)

    2016-12-15

    Six samples from a natural outcrop of reservoir rocks with oil seepage and two control samples from surrounding area in the Minhe Basin, northwestern China were selectively collected and analyzed for mineralogical composition as well as iron speciation using X-ray powder diffraction (XRD) and Mössbauer spectroscopy, respectively. Iron species revealed that: (1) the oil-bearing reservoir rocks were changed by water-rock-oil interactions; (2) even in the same site, there was a different performance between sandstone and mudstone during the oil and gas infusion to the reservoirs; and (3) this was evidence indicating the selective channels of hydrocarbon migration. In addition, these studies showed that the iron speciation by Mössbauer spectroscopy could be useful for the study of oil and gas reservoirs, especially the processes of the water-rock interactions within petroleum reservoirs.

  7. Geology, Streamflow, and Water Chemistry of the Talufofo Stream Basin, Saipan, Northern Mariana Islands

    Science.gov (United States)

    Izuka, Scot K.; Ewart, Charles J.

    1995-01-01

    A study of the geology, streamflow, and water chemistry of Talufofo Stream Basin, Saipan, Commonwealth of the Northern Mariana Islands, was undertaken to determine the flow characteristics of Talufofo Stream and the relation to the geology of the drainage basin. The Commonwealth government is exploring the feasibility of using water from Talufofo Stream to supplement Saipan's stressed municipal water supply. Streamflow records from gaging stations on the principal forks of Talufofo Stream indicate that peak streamflows and long-term average flow are higher at the South Fork gaging station than at the Middle Fork gaging station because the drainage area of the South Fork gaging station is larger, but persistent base flow from ground-water discharge during dry weather is greater in the Middle Fork gaging station. The sum of the average flows at the Middle Fork and South Fork gaging stations, plus an estimate of the average flow at a point in the lower reaches of the North Fork, is about 2.96 cubic feet per second or 1.91 million gallons per day. Although this average represents the theoretical maximum long-term draft rate possible from the Talufofo Stream Basin if an adequate reservoir can be built, the actual amount of surface water available will be less because of evaporation, leaks, induced infiltration, and reservoir-design constraints. Base-flow characteristics, such as stream seepage and spring discharge, are related to geology of the basin. Base flow in the Talufofo Stream Basin originates as discharge from springs near the base of limestones located in the headwaters of Talufofo Stream, flows over low-permeability volcanic rocks in the middle reaches, and seeps back into the high-permeability limestones in the lower reaches. Water sampled from Talufofo Stream during base flow had high dissolved-calcium concentrations (between 35 and 98 milligrams per liter), characteristic of water from a limestone aquifer. Concentrations of potassium, sodium, and chloride

  8. Optimization Model for cooperative water allocation and valuation in large river basins regarding environmental constraints

    Science.gov (United States)

    Pournazeri, S.

    2011-12-01

    A comprehensive optimization model named Cooperative Water Allocation Model (CWAM) is developed for equitable and efficient water allocation and valuation of Zab river basin in order to solve the draught problems of Orumieh Lake in North West of Iran. The model's methodology consists of three phases. The first represents an initial water rights allocation among competing users. The second comprises the water reallocation process for complete usage by consumers. The third phase performs an allocation of the net benefit of the stakeholders participating in a coalition by applying cooperative game theory. The environmental constraints are accounted for in the water allocation model by entering probable environmental damage in a target function, and inputting the minimum water requirement of users. The potential of underground water usage is evaluated in order to compensate for the variation in the amount of surface water. This is conducted by applying an integrated economic- hydrologic river basin model. A node-link river basin network is utilized in CWAM which consists of two major blocks. The first indicates the internal water rights allocation and the second is associated to water and net benefit reallocation. System control, loss in links by evaporation or seepage, modification of inflow into the node, loss in nodes and loss in outflow are considered in this model. Water valuation is calculated for environmental, industrial, municipal and agricultural usage by net benefit function. It can be seen that the water rights are allocated efficiently and incomes are distributed appropriately based on quality and quantity limitations.

  9. A framework model for water-sharing among co-basin states of a river basin

    Science.gov (United States)

    Garg, N. K.; Azad, Shambhu

    2018-05-01

    A new framework model is presented in this study for sharing of water in a river basin using certain governing variables, in an effort to enhance the objectivity for a reasonable and equitable allocation of water among co-basin states. The governing variables were normalised to reduce the governing variables of different co-basin states of a river basin on same scale. In the absence of objective methods for evaluating the weights to be assigned to co-basin states for water allocation, a framework was conceptualised and formulated to determine the normalised weighting factors of different co-basin states as a function of the governing variables. The water allocation to any co-basin state had been assumed to be proportional to its struggle for equity, which in turn was assumed to be a function of the normalised discontent, satisfaction, and weighting factors of each co-basin state. System dynamics was used effectively to represent and solve the proposed model formulation. The proposed model was successfully applied to the Vamsadhara river basin located in the South-Eastern part of India, and a sensitivity analysis of the proposed model parameters was carried out to prove its robustness in terms of the proposed model convergence and validity over the broad spectrum values of the proposed model parameters. The solution converged quickly to a final allocation of 1444 million cubic metre (MCM) in the case of the Odisha co-basin state, and to 1067 MCM for the Andhra Pradesh co-basin state. The sensitivity analysis showed that the proposed model's allocation varied from 1584 MCM to 1336 MCM for Odisha state and from 927 to 1175 MCM for Andhra, depending upon the importance weights given to the governing variables for the calculation of the weighting factors. Thus, the proposed model was found to be very flexible to explore various policy options to arrive at a decision in a water sharing problem. It can therefore be effectively applied to any trans-boundary problem where

  10. Infinite slope stability under steady unsaturated seepage conditions

    Science.gov (United States)

    Lu, Ning; Godt, Jonathan W.

    2008-01-01

    We present a generalized framework for the stability of infinite slopes under steady unsaturated seepage conditions. The analytical framework allows the water table to be located at any depth below the ground surface and variation of soil suction and moisture content above the water table under steady infiltration conditions. The framework also explicitly considers the effect of weathering and porosity increase near the ground surface on changes in the friction angle of the soil. The factor of safety is conceptualized as a function of the depth within the vadose zone and can be reduced to the classical analytical solution for subaerial infinite slopes in the saturated zone. Slope stability analyses with hypothetical sandy and silty soils are conducted to illustrate the effectiveness of the framework. These analyses indicate that for hillslopes of both sandy and silty soils, failure can occur above the water table under steady infiltration conditions, which is consistent with some field observations that cannot be predicted by the classical infinite slope theory. A case study of shallow slope failures of sandy colluvium on steep coastal hillslopes near Seattle, Washington, is presented to examine the predictive utility of the proposed framework.

  11. 78 FR 1306 - Transition Period Under Section 716 of the Dodd-Frank Wall Street Reform and Consumer Protection Act

    Science.gov (United States)

    2013-01-08

    ... DEPARTMENT OF THE TREASURY Office of the Comptroller of the Currency [Docket ID OCC-2013-0001] Transition Period Under Section 716 of the Dodd-Frank Wall Street Reform and Consumer Protection Act AGENCY... Dodd-Frank Wall Street Reform and Consumer Protection Act (Dodd-Frank Act) prohibits providing Federal...

  12. Changing composition of microbial communities indicates seepage fluid difference of the Thuwal Seeps in the Red Sea

    KAUST Repository

    Yang, Bo

    2015-06-10

    © Springer International Publishing Switzerland 2015. Cold seeps are unique ecosystems that are generally characterized by high salinity and reducing solutions. Seepage fluid, the major water influx of this system, contains hypersaline water, sediment pore water, and other components. The Thuwal cold seeps were recently discovered on the continental margin of the Red Sea. Using 16S rRNA gene pyro-sequencing technology, microbial communities were investigated by comparing samples collected in 2011 and 2013. The results revealed differences in the microbial communities between the two sampling times. In particular, a significantly higher abundance of Marine Group I (MGI) Thaumarchaeota was coupled with lower salinity in 2013. In the brine pool, the dominance of Desulfobacterales in 2011 was supplanted byMGI Thaumarchaeota in 2013, perhaps due to a reduced supply of hydrogen sulfide from the seepage fluid. Collectively, this study revealed a difference in water components in this ecosystem between two sampling times. The results indicated that the seawater in this cold seep displayed a greater number of characteristics of normal seawater in 2013 than in 2011, which might represent the dominant driving force for changes in microbial community structures. This is the first study to provide a temporal comparison of the microbial biodiversity of a cold seep ecosystem in the Red Sea.

  13. Changing composition of microbial communities indicates seepage fluid difference of the Thuwal Seeps in the Red Sea

    KAUST Repository

    Yang, Bo; Zhang, Weipeng; Tian, Renmao; Wang, Yong; Qian, Pei-Yuan

    2015-01-01

    © Springer International Publishing Switzerland 2015. Cold seeps are unique ecosystems that are generally characterized by high salinity and reducing solutions. Seepage fluid, the major water influx of this system, contains hypersaline water, sediment pore water, and other components. The Thuwal cold seeps were recently discovered on the continental margin of the Red Sea. Using 16S rRNA gene pyro-sequencing technology, microbial communities were investigated by comparing samples collected in 2011 and 2013. The results revealed differences in the microbial communities between the two sampling times. In particular, a significantly higher abundance of Marine Group I (MGI) Thaumarchaeota was coupled with lower salinity in 2013. In the brine pool, the dominance of Desulfobacterales in 2011 was supplanted byMGI Thaumarchaeota in 2013, perhaps due to a reduced supply of hydrogen sulfide from the seepage fluid. Collectively, this study revealed a difference in water components in this ecosystem between two sampling times. The results indicated that the seawater in this cold seep displayed a greater number of characteristics of normal seawater in 2013 than in 2011, which might represent the dominant driving force for changes in microbial community structures. This is the first study to provide a temporal comparison of the microbial biodiversity of a cold seep ecosystem in the Red Sea.

  14. Hydrothermal dolomite reservoir facies in the Sinian Dengying Fm, central Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Yuqiang Jiang

    2017-07-01

    Full Text Available The Upper Sinian Dengying Fm is the focus of natural gas exploration in the central part of the Sichuan Basin (central Sichuan Basin in recent years. Especially, epigenic karstification and its resulted reservoir-seepage spaces have always been the focal points in researches. Based on the petrographic characteristics of drilling cuttings and core samples, and through experimental analysis by using trace elements, isotopes, and cathodoluminescence, the Dengying Fm dolomite was demonstrated to have matrix recrystallized dolomite (MRD, filled saddle dolomite (FSD (the mean homogenization temperature of inclusion: 178.5 °C, high concentrations of Fe & Mn, slightly positive 87Sr/86Sr value and hydrothermal minerals combination (including sphalerite, galena, pyrite, and quartz, etc.. Thus, it was proposed that hydrothermal dolomite reservoir facies (HDRF exist in the Dengying Fm dolomite, in other words, the dolomite reservoir is composed of hydrothermal dissolved pores, intercrystalline pores of hydrothermal origin, hydrothermal caverns and expanded fractures, and was formed due to the reworking of hydrothermal fluid on tight matrix dolomite. Identification marks are presented in terms of petrography and geochemistry so that hydrothermal dolomite reservoir facies can be effectively recognized and identified. It is concluded that the development of hydrothermal dolomite reservoir facies in this area are preliminary controlled by deep and large basement faults and the strength of hydrothermal fluids.

  15. The influence of environmental factors and dredging on chironomid larval diversity in urban drainage systems in polders strongly influenced by seepage from large rivers

    DEFF Research Database (Denmark)

    Vermonden, K.; Brodersen, Klaus Peter; Jacobsen, Dean

    2011-01-01

    , in urban waters strongly influenced by seepage of large rivers. Chironomid assemblages were studied in urban surface-water systems (man-made drainage ditches) in polder areas along lowland reaches of the rivers Rhine-Meuse in The Netherlands. Multivariate analysis was used to identify the key environmental...... factors. Taxon richness, Shannon index (H'), rareness of species, and life-history strategies at urban locations were compared with available data from similar man-made water bodies in rural areas, and the effectiveness of dredging for restoring chironomid diversity in urban waters was tested. Three...... diversity of chironomid communities in urban waters affected by nutrient-rich seepage or inlet of river water...

  16. Geochemical and visual indicators of hydrothermal fluid flow through a sediment-hosted volcanic ridge in the Central Bransfield Basin (Antarctica.

    Directory of Open Access Journals (Sweden)

    Alfred Aquilina

    Full Text Available In the austral summer of 2011 we undertook an investigation of three volcanic highs in the Central Bransfield Basin, Antarctica, in search of hydrothermal activity and associated fauna to assess changes since previous surveys and to evaluate the extent of hydrothermalism in this basin. At Hook Ridge, a submarine volcanic edifice at the eastern end of the basin, anomalies in water column redox potential (E(h were detected close to the seafloor, unaccompanied by temperature or turbidity anomalies, indicating low-temperature hydrothermal discharge. Seepage was manifested as shimmering water emanating from the sediment and from mineralised structures on the seafloor; recognisable vent endemic fauna were not observed. Pore fluids extracted from Hook Ridge sediment were depleted in chloride, sulfate and magnesium by up to 8% relative to seawater, enriched in lithium, boron and calcium, and had a distinct strontium isotope composition ((87Sr/(86Sr = 0.708776 at core base compared with modern seawater ((87Sr/(86Sr ≈ 0.70918, indicating advection of hydrothermal fluid through sediment at this site. Biogeochemical zonation of redox active species implies significant moderation of the hydrothermal fluid with in situ diagenetic processes. At Middle Sister, the central ridge of the Three Sisters complex located about 100 km southwest of Hook Ridge, small water column E(h anomalies were detected but visual observations of the seafloor and pore fluid profiles provided no evidence of active hydrothermal circulation. At The Axe, located about 50 km southwest of Three Sisters, no water column anomalies in E(h, temperature or turbidity were detected. These observations demonstrate that the temperature anomalies observed in previous surveys are episodic features, and suggest that hydrothermal circulation in the Bransfield Strait is ephemeral in nature and therefore may not support vent biota.

  17. Methane seepage intensities traced by biomarker patterns in authigenic carbonates from the South China Sea

    Science.gov (United States)

    Guan, H.; Feng, D.

    2015-12-01

    Authigenic carbonate rocks from an active seep (Site F) at 1120 m water depth of the South China Sea (SCS) were studied using mineralogical and lipid biomarker analyses. Carbonate mineral compositions, in specific samples, were predominantly aragonite, high-Mg calcite (HMC), or a mixture of both. Abundant 13C-depleted lipid biomarkers (various isoprenoids) diagnostic for archaea provide evidence that anaerobic oxidation of methane (AOM) mediated by anaerobic methane oxidizing archaea (ANME) and their bacterial partners is the major process leading to formation of the carbonates. Nearly a pure suite of AOM biomarkers was preserved in aragonitic carbonate in which predominant consortia were most likely ANME-2/Desulfosarcina & Desulfococcus (DSS) assemblages and a mixture of ANME-2/DSS and ANME-1/DSS consortia in the mixed mineral sample, the predominant consortia are in good accordance with the point that the relative higher methane seepage intensity favors the precipitation of aragonite over HMC. In contrast, the completely different biomarker patterns in HMC sample were mainly composed terrestrial organic matter and marine Thaumarchaea, which most likely originally within sediments accompanied with high organic matter input and low methane supply. This environment is known to be favored for archaea of ANME-1 and precipitation of HMC. High concentrations of 13C-depleted hopanoids, including diplopterol, hopanoic acids and hopanols were observed in the aragonite sample that may be sourced by the intermittent presence of oxic conditions in an overall anoxic condition, which was possibly induced by changing seepage intensities.

  18. SIMULATION OF RAINFALL AND SEEPAGE FLOW ON UNSATURATED SOIL BY A SEEPAGE-DEFORMATION COUPLED METHOD SIMULACIÓN DE LLUVIA E INFILTRACIÓN EN SUELOS PARCIALMENTE SATURADOS USANDO UN METODO ACOPLADO INFILTRACIÓN-DEFORMACIÓN

    Directory of Open Access Journals (Sweden)

    Edwin García-Aristizábal

    2012-06-01

    Full Text Available This paper presents an application for the analysis of structures formed by unsaturated layered soils subjected to rainfall and seepage flow; the results are part of a current research project on rainfall infiltration. A three-phase coupled infiltration-deformation method for unsaturated soil was used for the numerical analysis. The effects of the water permeability and horizontal drainage on the distribution of seepage flow velocities, saturation, and generation of deformations for an unsaturated layered embankment were investigated. The results show that the generation of deformation on the embankment surface highly depends on the water permeability of the soil. In addition, through horizontal drainage simulations, the advantage of this type of solution for decreasing the pore water pressures on the back of the slope embankment, thus avoiding local failure (erosion, is shown.Este artículo presenta una aplicación para el análisis de estructuras compuestas por suelos parcialmente saturados que están sometidas al efecto de la lluvia y la infiltración; los resultados hacen parte de una investigación en curso relacionada con infiltración de aguas lluvias. Para los análisis numéricos se utilizó un método trifásico acoplado de infiltración-deformación. Se investigaron los efectos que tienen la permeabilidad y el drenaje lateral en la distribución de los vectores de velocidad de infiltración, la saturación y la generación de deformaciones para un terraplén estratificado y parcialmente saturado. Los resultados muestran que la generación de deformación en el talud del terraplén depende, en gran parte, de la permeabilidad del suelo. Adicionalmente, por medio de simulación de drenes horizontales, se muestra la ventaja de este tipo de solución para disminuir las presiones de poros internas en el talud del terraplén, evitando la falla local (erosión.

  19. F-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    1992-09-01

    This progress report from the Savannah River Plant for second quarter 1992 includes discussion on the following topics: description of facilities; hydrostratigraphic units; monitoring well nomenclature; integrity of the monitoring well network; groundwater monitoring data; analytical results exceeding standards; tritium, nitrate, and pH time-trend data; water levels; groundwater flow rates and directions; upgradient versus downgradient results

  20. F-Area Seepage Basins groundwater monitoring report

    International Nuclear Information System (INIS)

    1992-06-01

    This progress report from the Savannah River Plant for first quarter 1992 includes discussion on the following topics: description of facilities; hydrostratigraphic units; monitoring well nomenclature; integrity of the monitoring well network; groundwater monitoring data; analytical results exceeding standards; tritium, nitrate, and pH time-trend data; water levels; groundwater flow rates and directions; upgradient versus downgradient results

  1. Modeling of coupled heat transfer and reactive transport processes in porous media: Application to seepage studies at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Mukhopadhyay, Sumit; Sonnenthal, Eric L.; Spycher, Nicolas

    2007-01-01

    When hot radioactive waste is placed in subsurface tunnels, a series of complex changes occurs in the surrounding medium. The water in the pore space of the medium undergoes vaporization and boiling. Subsequently, vapor migrates out of the matrix pore space, moving away from the tunnel through the permeable fracture network. This migration is propelled by buoyancy, by the increased vapor pressure caused by heating and boiling, and through local convection. In cooler regions, the vapor condenses on fracture walls, where it drains through the fracture network. Slow imbibition of water thereafter leads to gradual rewetting of the rock matrix. These thermal and hydrological processes also bring about chemical changes in the medium. Amorphous silica precipitates from boiling and evaporation, and calcite from heating and CO2 volatilization. The precipitation of amorphous silica, and to a much lesser extent calcite, results in long-term permeability reduction. Evaporative concentration also results in the precipitation of gypsum (or anhydrite), halite, fluorite and other salts. These evaporative minerals eventually redissolve after the boiling period is over, however, their precipitation results in a significant temporary decrease in permeability. Reduction of permeability is also associated with changes in fracture capillary characteristics. In short, the coupled thermal-hydrological-chemical (THC) processes dynamically alter the hydrological properties of the rock. A model based on the TOUGHREACT reactive transport software is presented here to investigate the impact of THC processes on flow near an emplacement tunnel at Yucca Mountain, Nevada. We show how transient changes in hydrological properties caused by THC processes often lead to local flow channeling and saturation increases above the tunnel. For models that include only permeability changes to fractures, such local flow channeling may lead to seepage relative to models where THC effects are ignored. However

  2. Modeling of coupled heat transfer and reactive transport processes in porous media: Application to seepage studies at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Mukhopadhyay, S.; Sonnenthal, E.L.; Spycher, N.

    2007-01-01

    When hot radioactive waste is placed in subsurface tunnels, a series of complex changes occurs in the surrounding medium. The water in the pore space of the medium undergoes vaporization and boiling. Subsequently, vapor migrates out of the matrix pore space, moving away from the tunnel through the permeable fracture network. This migration is propelled by buoyancy, by the increased vapor pressure caused by heating and boiling, and through local convection. In cooler regions, the vapor condenses on fracture walls, where it drains through the fracture network. Slow imbibition of water thereafter leads to gradual rewetting of the rock matrix. These thermal and hydrological processes also bring about chemical changes in the medium. Amorphous silica precipitates from boiling and evaporation, and calcite from heating and CO 2 volatilization. The precipitation of amorphous silica, and to a much lesser extent calcite, results in long-term permeability reduction. Evaporative concentration also results in the precipitation of gypsum (or anhydrite), halite, fluorite and other salts. These evaporative minerals eventually redissolve after the boiling period is over, however, their precipitation results in a significant temporary decrease in permeability. Reduction of permeability is also associated with changes in fracture capillary characteristics. In short, the coupled thermal-hydrological-chemical (THC) processes dynamically alter the hydrological properties of the rock. A model based on the TOUGHREACT reactive transport software is presented here to investigate the impact of THC processes on flow near an emplacement tunnel at Yucca Mountain, Nevada. We show how transient changes in hydrological properties caused by THC processes often lead to local flow channeling and saturation increases above the tunnel. For models that include only permeability changes to fractures, such local flow channeling may lead to seepage relative to models where THC effects are ignored. However

  3. Evaluating connection of aquifers to springs and streams, Great Basin National Park and vicinity, Nevada

    Science.gov (United States)

    Prudic, David E.; Sweetkind, Donald S.; Jackson, Tracie R.; Dotson, K. Elaine; Plume, Russell W.; Hatch, Christine E.; Halford, Keith J.

    2015-12-22

    Federal agencies that oversee land management for much of the Snake Range in eastern Nevada, including the management of Great Basin National Park by the National Park Service, need to understand the potential extent of adverse effects to federally managed lands from nearby groundwater development. As a result, this study was developed (1) to attain a better understanding of aquifers controlling groundwater flow on the eastern side of the southern part of the Snake Range and their connection with aquifers in the valleys, (2) to evaluate the relation between surface water and groundwater along the piedmont slopes, (3) to evaluate sources for Big Springs and Rowland Spring, and (4) to assess groundwater flow from southern Spring Valley into northern Hamlin Valley. The study focused on two areas—the first, a northern area along the east side of Great Basin National Park that included Baker, Lehman, and Snake Creeks, and a second southern area that is the potential source area for Big Springs. Data collected specifically for this study included the following: (1) geologic field mapping; (2) drilling, testing, and water quality sampling from 7 test wells; (3) measuring discharge and water chemistry of selected creeks and springs; (4) measuring streambed hydraulic gradients and seepage rates from 18 shallow piezometers installed into the creeks; and (5) monitoring stream temperature along selected reaches to identify places of groundwater inflow.

  4. Characterization of the Spatial and Temporal Variations of Submarine Groundwater Discharge Using Electrical Resistivity and Seepage Measurements

    Science.gov (United States)

    Durand, Josephine Miryam Kalyanie

    Submarine groundwater discharge (SGD) encompasses all fluids crossing the sediment/ocean interface, regardless of their origin, composition or driving forces. SGD provides a pathway for terrestrial contaminants that can significantly impact coastal ecosystems. Overexploitation of groundwater resources can decrease SGD which favors seawater intrusion at depth. Understanding SGD is therefore crucial for water quality and resource management. Quantifying SGD is challenging due to its diffuse and heterogeneous nature, in addition to significant spatio-temporal variations at multiple scales. In this thesis, an integrated approach combining electrical resistivity (ER) surveys, conductivity and temperature point measurements, seepage rates using manual and ultrasonic seepage meters, and pore fluid salinities was used to characterize SGD spatio-temporal variations and their implications for contaminant transport at several locations on Long Island, NY. The influence of surficial sediments on SGD distribution was investigated in Stony Brook Harbor. A low-permeability mud layer, actively depositing in the harbor, limits SGD at the shoreline, prevents mixing with seawater and channels a significant volume of freshwater offshore. SGD measured at locations without mud is high and indicates significant mixing between porewater and seawater. A 2D steady-state density-difference numerical model of the harbor was developed using SEAWAT and was validated by our field observations. Temporal variations of SGD due to semi-diurnal tidal forcing were studied in West Neck Bay, Shelter Island, using a 12-hr time-lapse ER survey together with continuous salinity and seepage measurements in the intertidal zone. The observed dynamic patterns of groundwater flux and salinity distribution disagree with published standard transient state numerical models, suggesting the need for developing more specific models of non-homogeneous anisotropic aquifers. SGD distribution and composition were

  5. Geohydrology and numerical simulation of groundwater flow in the central Virgin River Basin of Iron and Washington Counties, Utah

    Science.gov (United States)

    Heilweil, V.M.; Freethey, G.W.; Wilkowske, C.D.; Stolp, B.J.; Wilberg, D.E.

    2000-01-01

    Because rapid growth of communities in Washington and Iron Counties, Utah, is expected to cause an increase in the future demand for water resources, a hydrologic investigation was done to better understand ground-water resources within the central Virgin River basin. This study focused on two of the principal ground-water reservoirs within the basin: the upper Ash Creek basin ground-water system and the Navajo and Kayenta aquifer system.The ground-water system of the upper Ash Creek drainage basin consists of three aquifers: the uppermost Quaternary basin-fill aquifer, the Tertiary alluvial-fan aquifer, and the Tertiary Pine Valley monzonite aquifer. These aquifers are naturally bounded by the Hurricane Fault and by drainage divides. On the basis of measurements, estimates, and numerical simulations of reasonable values for all inflow and outflow components, total water moving through the upper Ash Creek drainage basin ground-water system is estimated to be about 14,000 acre-feet per year. Recharge to the upper Ash Creek drainage basin ground-water system is mostly from infiltration of precipitation and seepage from ephemeral and perennial streams. The primary source of discharge is assumed to be evapotranspiration; however, subsurface discharge near Ash Creek Reservoir also may be important.The character of two of the hydrologic boundaries of the upper Ash Creek drainage basin ground-water system is speculative. The eastern boundary provided by the Hurricane Fault is assumed to be a no-flow boundary, and a substantial part of the ground-water discharge from the system is assumed to be subsurface outflow beneath Ash Creek Reservoir along the southern boundary. However, these assumptions might be incorrect because alternative numerical simulations that used different boundary conditions also proved to be feasible. The hydrogeologic character of the aquifers is uncertain because of limited data. Differences in well yield indicate that there is considerable

  6. A phase I open-label dose-escalation study of the anti-HER3 monoclonal antibody LJM716 in patients with advanced squamous cell carcinoma of the esophagus or head and neck and HER2-overexpressing breast or gastric cancer.

    Science.gov (United States)

    Reynolds, Kerry Lynn; Bedard, Philippe L; Lee, Se-Hoon; Lin, Chia-Chi; Tabernero, Josep; Alsina, Maria; Cohen, Ezra; Baselga, José; Blumenschein, George; Graham, Donna M; Garrido-Laguna, Ignacio; Juric, Dejan; Sharma, Sunil; Salgia, Ravi; Seroutou, Abdelkader; Tian, Xianbin; Fernandez, Rose; Morozov, Alex; Sheng, Qing; Ramkumar, Thiruvamoor; Zubel, Angela; Bang, Yung-Jue

    2017-09-12

    Human epidermal growth factor receptor 3 (HER3) is important in maintaining epidermal growth factor receptor-driven cancers and mediating resistance to targeted therapy. A phase I study of anti-HER3 monoclonal antibody LJM716 was conducted with the primary objective to identify the maximum tolerated dose (MTD) and/or recommended dose for expansion (RDE), and dosing schedule. Secondary objectives were to characterize safety/tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity. This open-label, dose-finding study comprised dose escalation, followed by expansion in patients with squamous cell carcinoma of the head and neck or esophagus, and HER2-overexpressing metastatic breast cancer or gastric cancer. During dose escalation, patients received LJM716 intravenous once weekly (QW) or every two weeks (Q2W), in 28-day cycles. An adaptive Bayesian logistic regression model was used to guide dose escalation and establish the RDE. Exploratory pharmacodynamic tumor studies evaluated modulation of HER3 signaling. Patients received LJM716 3-40 mg/kg QW and 20 mg/kg Q2W (54 patients; 36 patients at 40 mg/kg QW). No dose-limiting toxicities (DLTs) were reported during dose-escalation. One patient experienced two DLTs (diarrhea, hypokalemia [both grade 3]) in the expansion phase. The RDE was 40 mg/kg QW, providing drug levels above the preclinical minimum effective concentration. One patient with gastric cancer had an unconfirmed partial response; 17/54 patients had stable disease, two lasting >30 weeks. Down-modulation of phospho-HER3 was observed in paired tumor samples. LJM716 was well tolerated; the MTD was not reached, and the RDE was 40 mg/kg QW. Further development of LJM716 is ongoing. Clinicaltrials.gov registry number NCT01598077 (registered on 4 May, 2012).

  7. Hydrogeology, groundwater seepage, nitrate distribution, and flux at the Raleigh hydrologic research station, Wake County, North Carolina, 2005-2007

    Science.gov (United States)

    McSwain, Kristen Bukowski; Bolich, Richard E.; Chapman, Melinda J.

    2013-01-01

    gradients in the groundwater discharge area near the Neuse River were complex and were affected by fluctuations in river stage, with the exception of a well completed in a diabase dike. Water-quality data from the wells and surface-water sites at the RHRS were collected continuously as well as during periodic sampling events. Surface-water samples collected from a tributary were most similar in chemical composition to groundwater found in the regolith and transition zone. Nitrate (measured as nitrite plus nitrate, as nitrogen) concentrations in the sampled wells and tributary ranged from about 5 to more than 120 milligrams per liter as nitrogen. Waterborne continuous resistivity profiling conducted on the Neuse River in the area of the RHRS measured areas of low apparent resistivity that likely represent groundwater contaminated by high concentrations of nitrate. These areas were located on either side of a diabase dike and at the outfall of two unnamed tributaries. The diabase dike preferentially directed the discharge of groundwater to the Neuse River and may isolate groundwater movement laterally. Discrete temperature measurements made within the pore water beneath the Neuse River revealed seeps of colder groundwater discharging into warmer surface water near a diabase dike. Water-quality samples collected from the pore water beneath the Neuse River indicated that nitrate was present at concentrations as high as 80 milligrams per liter as nitrogen on the RHRS side of the river. The highest concentrations of nitrate were located within pore water collected from an area near a diabase dike that was identified as a suspected seepage area. Hydraulic head was measured and pore water samples were collected from two 140-centimeter-deep (55.1-inch-deep) multiport piezometers that were installed in bed sediments on opposite sides of a diabase dike. The concentration of nitrate in pore water at a suspected seepage area ranged from 42 to 82 milligrams per liter as nitrogen with a

  8. Reduced gas seepages in ophiolitic complexes: Evidences for multiple origins of the H2-CH4-N2 gas mixtures

    Science.gov (United States)

    Vacquand, Christèle; Deville, Eric; Beaumont, Valérie; Guyot, François; Sissmann, Olivier; Pillot, Daniel; Arcilla, Carlo; Prinzhofer, Alain

    2018-02-01

    This paper proposes a comparative study of reduced gas seepages occurring in ultrabasic to basic rocks outcropping in ophiolitic complexes based on the study of seepages from Oman, the Philippines, Turkey and New Caledonia. This study is based on analyses of the gas chemical composition, noble gases contents, stable isotopes of carbon, hydrogen and nitrogen. These seepages are mostly made of mixtures of three main components which are H2, CH4 and N2 in various proportions. The relative contents of the three main gas components show 4 distinct types of gas mixtures (H2-rich, N2-rich, N2-H2-CH4 and H2-CH4). These types are interpreted as reflecting different zones of gas generation within or below the ophiolitic complexes. In the H2-rich type, associated noble gases display signatures close to the value of air. In addition to the atmospheric component, mantle and crustal contributions are present in the N2-rich, N2-H2-CH4 and H2-CH4 types. H2-bearing gases are either associated with ultra-basic (pH 10-12) spring waters or they seep directly in fracture systems from the ophiolitic rocks. In ophiolitic contexts, ultrabasic rocks provide an adequate environment with available Fe2+ and alkaline conditions that favor H2 production. CH4 is produced either directly by reaction of dissolved CO2 with basic-ultrabasic rocks during the serpentinization process or in a second step by H2-CO2 interaction. H2 is present in the gas when no more carbon is available in the system to generate CH4. The N2-rich type is notably associated with relatively high contents of crustal 4He and in this gas type N2 is interpreted as issued mainly from sediments located below the ophiolitic units.

  9. Assessment of linear anionic polyacrylamide application to irrigation canals for seepage control

    Directory of Open Access Journals (Sweden)

    Hamil Uribe

    2013-09-01

    Full Text Available South- central area of Chile area has a Mediterranean climate and high crop water requirements. Irrigation water is distributed through long channels which have low water conveyance efficiency (Ec, difficult to improve by conventional techniques. The objective of this study was to quantify Ec and to evaluate the use of Linear Anionic Polyacrylamide (LA-PAM to reduce seepage losses. The study was carried out in south-central area of Chile, (UTM Coordinate N 5745000; E 725000 m, datum is WGS-84, zone 18S in 250 km of channels whose flow varied between 0.12 and 24.6 m3 s–1. Water users indicated channel reaches with potential low Ec, which were selected for LA-PAM application. In 11 reaches between 0.51 and 3 km in length, 1 to 3 LAPAM applications were performed at rates of 10 kg ha–1, considering the wet perimeter area as basis of calculation. Thirty-one LA-PAM applications were performed over a 30.5 km length. Most of the channels were large enough to allow motorboat moving against the current to carry-out LA-PAM application. Water flow was measured (StreamPro ADCP at both ends of selected reaches before and after granular LAPAM application. Weekly measurements were made to quantify treatment effect duration. Water turbidity and temperature were measured. Channels showed variable Ec from 87% to 94%. Two reaches showed 6% water gains. In more than 80% cases LA-PAM effect was positive, achieving loss reductions of 15 to 760 L s–1. In other cases LA-PAM had a negative effect since it mainly affected water entry into the channel. It was determined that field conditions referred by users as indicators of Ec are not always correct and vary in time according to climatic conditions. Ec was estimated and it was possible to reduce seepage through LA-PAM applications. This allow increasing irrigation security in critical periods, especially under drought conditions.

  10. Geohydrology and numerical simulation of ground-water flow in the central Virgin River basin of Iron and Washington Countries, Utah

    Science.gov (United States)

    Heilweil, V.M.; Freethey, G.W.; Wilkowske, C.D.; Stolp, B.J.; Wilberg, D.E.

    2000-01-01

    Because rapid growth of communities in Washington and Iron Counties, Utah, is expected to cause an increase in the future demand for water resources, a hydrologic investigation was done to better understand ground-water resources within the central Virgin River basin. This study focused on two of the principal ground-water reservoirs within the basin: the upper Ash Creek basin ground-water system and the Navajo and Kayenta aquifer system. The ground-water system of the upper Ash Creek drainage basin consists of three aquifers: the uppermost Quaternary basin-fill aquifer, the Tertiary alluvial-fan aquifer, and the Tertiary Pine Valley monzonite aquifer. These aquifers are naturally bounded by the Hurricane Fault and by drainage divides. On the basis of measurements, estimates, and numerical simulations of reasonable values for all inflow and outflow components, total water moving through the upper Ash Creek drainage basin ground-water system is estimated to be about 14,000 acre-feet per year. Recharge to the upper Ash Creek drainage basin ground-water system is mostly from infiltration of precipitation and seepage from ephemeral and perennial streams. The primary source of discharge is assumed to be evapotranspiration; however, subsurface discharge near Ash Creek Reservoir also may be important. The character of two of the hydrologic boundaries of the upper Ash Creek drainage basin ground-water system is speculative. The eastern boundary provided by the Hurricane Fault is assumed to be a no-flow boundary, and a substantial part of the ground-water discharge from the system is assumed to be subsurface outflow beneath Ash Creek Reservoir along the southern boundary. However, these assumptions might be incorrect because alternative numerical simulations that used different boundary conditions also proved to be feasible. The hydrogeologic character of the aquifers is uncertain because of limited data. Difference in well yield indicate that there is considerable

  11. Results of the Quarterly Tritium Survey of Fourmile Branch and Its Seeplines in the F and H Areas of SRS: May 1995

    International Nuclear Information System (INIS)

    Koch, J.W.; Dixon, K.L.

    1995-01-01

    The Environmental Sciences Section of the Savannah River Technology Center established a quarterly monitoring program of the Fourmile Branch stream and its associated seepline located down gradient from the F- and H-Area Seepage Basins. The primary focus of this program was to survey and track changes in tritium levels; however, specific conductivity, and pH were also surveyed and tracked. The measurement from the eleventh survey (May 1995) exhibited similar tritium levels, conductivity measurements, and pH values to data from previous sampling events. The overall results of the tritium survey and stream monitoring data (Looney et al., 1993) indicate that the tritium plume resulting from the past operation of the seepage basins continues to flush from the Fourmile Branch wetland system

  12. Characterization of light gaseous hydrocarbons of the surface soils of Krishna-Godavari basin, India.

    Science.gov (United States)

    Lakshmi, M; Rasheed, M A; Madhavi, T; Kalpana, M S; Patil, D J; Dayal, A M

    2012-01-01

    Several techniques are used for the exploration of hydrocarbons, of which; the geochemical techniques involving the microbiological technique use the principle of detecting the light hydrocarbon seepage activities for indication of sub-surface petroleum accumulations. Asurvey was carried out to characterize the light gaseous hydrocarbons seeping in oil and gas fields of Krishna-Godavari basin ofAndhra Pradesh. Aset of 50 sub-soil samples were collected at depths of about 3 m for geochemical analyses and 1m for microbiological analysis. The microbial prospecting studies showed the presence of high bacterial population for methane 2.5 x 10(2) to 6.0 x 10(6) cfu g(-1), propane 1x10(2) to 8.0 x 10(6) cfu g(-1) in soil samples. The adsorbed soil gas analysis showed the presence of moderate to low concentrations of methane (26 to 139 ppb), ethane (0 to 17 ppb), propane (0 to 8 ppb), butane (0 to 5 ppb) and pentane (0 to 2 ppb) in the soil samples of the study area. Carbon isotope analysis for methane ('13C1) ranging from -36.6 to -22.7 per hundred Pee Dee Belemnite (PDB) suggests these gases are of thermogenic origin. Geo-microbial prospecting method coupled with adsorbed soil gas and carbon isotope ratio analysis have thus shown good correlation with existing oil/gas fields of Krishna-Godavari basin.

  13. A system dynamics approach for integrated management of the Jucar River Basin

    Science.gov (United States)

    Rubio-Martin, Adria; Macian-Sorribes, Hector; Pulido-Velazquez, Manuel

    2017-04-01

    System dynamics (SD) is a modelling approach that allows the analysis of complex systems through the mathematical definition of variables and their relationships. Based on systems thinking, SD is suitable for interdisciplinary studies of the management of complex systems. Over the past 50 years, SD tools have been applied to fields as diverse as economics, ecology, politics, sociology and resource management. Its application to the field of water resources has grown significantly over the last two decades, facilitating the enhancement of models by adding social, economic and ecological components. However, its application to the operation of complex multireservoir systems has been very limited so far. In this contribution, we have developed a SD model for the Jucar River Basin, one of the most vulnerable basins in the western Mediterranean region with regard to droughts. The system has three main reservoirs, which allows for a multiannual management of the storage that compensates the highly variable streamflow from upstream. Our SD model of the Jucar River Basin is able to capture the complexity of the water resource system. The model developed consists of five interlinked subsystems: a) Topology of the system network, including the 3 main reservoirs, water seepage and evaporation, inflows and catchments. b) Monthly operating rules of each reservoir. The rules were derived from the expert knowledge eluded from the operators of the reservoirs. c) Monthly urban, agricultural and environmental water demands. d) State index of the system and drought mitigation measures triggered depending on the state index. e) Mancha Oriental aquifer and stream-aquifer interaction with the Jucar River. The comparison between observed and simulated series showed that the model provides a good representation of the observed reservoir operation and total deficits. The interdisciplinary and open nature of the methodology allows to add new variables and dynamics to the model that are

  14. Seepage water balance of the mixed tailings site IAA Dresden-Coschuetz/Gittersee by means of the two-dimensional model BOWAHALD

    International Nuclear Information System (INIS)

    Helling, C.; Dunger, V.

    1998-01-01

    Uranium mill tailings were deposited in a section of the Kaitzbach valley which was closed by tow dams. The Kaitzbach creek was cased in the area. After the uranium ore processing was finish the dump was used as a municipal waste deposit. The water balance of the IAA Dresden-Coschuetz/Gittersee was only estimated in former works. In this case a modeling of the water balance is very useful in regard to a process orientated quantification of the contaminant transport within the dump as well as into the underground. Simplified and rough estimating methods such as the runoff coefficient concept or rating curves are less suited because of the complexity of the processes. That's why we tried to get a runoff and seepage water balance by means of a two-dimensional water balance model for waste heaps called BOWAHALD. The tailings site IAA Dresden-Coschuetz/Gittersee was divited into several hydrotopes (areas with similar hydrological characteristics). Different exposition and slopes as well as different soils and vegetation were taken into account. The parameter verification is possible due to comparison with available data such hydrochemical and isotopic analysis of seepage water and groundwater. (orig.)

  15. Seepage determinations through auxiliary dike in Chingaza reservoir using radioactive tracers

    International Nuclear Information System (INIS)

    Sanches, L.; Obando, E.; Jimenez, G.; Torrez, E.

    1986-01-01

    Isotope techniques used in hydrology and developed during the last ten years in Colombia are usually tracer techniques based on the use of nuclides either introduced or naturally present in water. A problem of current content importance in hydraulics structures is seepage and the problems connected with it, such as impermeability of dams docks and their foundations. Many approaches are used to investigate these questions, but the simplest and most successful is the radiometric method. Radiometric observation of the flow of water through the earth dock involves introducing at a fixed point in the flow of water a radioactive solution and then following its movement downstream of the dock, and finding the place where it goes using appropriate detectors arranged at fixed control points. This paper describes the mean of choosing the injection points, the techniques for introducing radioactive solution and the conditions that must be borne in mind when selecting the radioisotope and determining its optimum activity. (author)

  16. Evaluation of baseline ground-water conditions in the Mosteiros, Ribeira Paul, and Ribeira Fajã Basins, Republic of Cape Verde, West Africa, 2005-06

    Science.gov (United States)

    Heilweil, Victor M.; Earle, John D.; Cederberg, Jay R.; Messer, Mickey M.; Jorgensen, Brent E.; Verstraeten, Ingrid M.; Moura, Miguel A.; Querido, Arrigo; Spencer,; Osorio, Tatiana

    2006-01-01

    This report documents current (2005-06) baseline ground-water conditions in three basins within the West African Republic of Cape Verde (Mosteiros on Fogo, Ribeira Paul on Santo Antão, and Ribeira Fajã on São Nicolau) based on existing data and additional data collected during this study. Ground-water conditions (indicators) include ground-water levels, ground-water recharge altitude, ground-water discharge amounts, ground-water age (residence time), and ground-water quality. These indicators are needed to evaluate (1) long-term changes in ground-water resources or water quality caused by planned ground-water development associated with agricultural projects in these basins, and (2) the feasibility of artificial recharge as a mitigation strategy to offset the potentially declining water levels associated with increased ground-water development.Ground-water levels in all three basins vary from less than a few meters to more than 170 meters below land surface. Continuous recorder and electric tape measurements at three monitoring wells (one per basin) showed variations between August 2005 and June 2006 of as much as 1.8 meters. Few historical water-level data were available for the Mosteiros or Ribeira Paul Basins. Historical records from Ribeira Fajã indicate very large ground-water declines during the 1980s and early 1990s, associated with dewatering of the Galleria Fajã tunnel. More-recent data indicate that ground-water levels in Ribeira Fajã have reached a new equilibrium, remaining fairly constant since the late 1990s.Because of the scarcity of observation wells within each basin, water-level data were combined with other techniques to evaluate ground-water conditions. These techniques include the quantification of ground-water discharge (well withdrawals, spring discharge, seepage to springs, and gallery drainage), field water-quality measurements, and the use of environmental tracers to evaluate sources of aquifer recharge, flow paths, and ground

  17. Evaluation of the conditions imposed by the fracture surface geometry on water seepage through fractured porous media

    International Nuclear Information System (INIS)

    Fuentes, Nestor O.; Faybishenko, B.

    2003-01-01

    In order to determine the geometric patterns of the fracture surfaces that imposes conditions on the fluid flow through fractured porous media, a series a fracture models have been analyzed using the RIMAPS technique and the variogram method. Results confirm that the main paths followed by the fluid channels are determined by the surface topography and remain constant during water seepage evolution. Characteristics scale lengths of both situations: fracture surface and the flow of water, are also found. There exists a relationship between the scale lengths corresponding to each situation. (author)

  18. Interpretation of Oil Seepage of Source Rock Based Magnetic Survey in Cipari Cilacap District

    Directory of Open Access Journals (Sweden)

    Sukmaji Anom Raharjo

    2015-12-01

    Full Text Available The magnetic survey had been conducted in Village of Cipari, District of Cipari, Region of  Cilacap to interpret to the location of the oil seepage source rock. Boundary of the research area is 108.75675°E – 108.77611°E and 7.42319°S – 7.43761°S. The observed total magnetic data is corrected and reducted to obtain the local magnetic anomaly data. The local magnetic anomaly data is applied to model the subsurface bodies anomalies based on the Mag2DC for Windows software. With be supported the geological information, the some bodies anomalies are interpreted as the basaltic igneous rock (c = 0.0051, the alternately of sandstone and claystone and insert of marl from Halang Formation (c = 0.0014, the breccia from Kumbang Formation (c = 0.0035, the alternately of sandstones and claystone with insert of marl and breccia from Halang Formation (c = 0.0036, the claystone from Tapak Formation (c = 0.0015, the alternately of sandstones and claystone with insert of marl and compacted breccia from Halang Formation (c = 0.0030, and the alternately of sandstone and claystone from   Halang Formation (c = 0.0020. The plantonic foraminifer fossils as resources of oil seepage are estimated in the sedimentaries rocks, where the oil flows from those rocks into the         reservoir (source rock. Based on the interpretation results, the source rock is above basaltic igneous rock with the approximate position is 108.76164°W and 7.43089°S; and the depth is 132.09 meters below the average topographic.

  19. Ensuring safe use of water in a river basin with uranium drainage

    International Nuclear Information System (INIS)

    Carvalho, F.; Oliveira, J.; Malta, M.

    2014-01-01

    A regular radioactivity monitoring programme ensures radioactivity surveillance in a river system with multiple and intensive uses of water. In the catchment of River Mondego, centre of Portugal, there is a uranium mining and milling legacy which encompasses about 12 old uranium mine sites and 3 uranium milling sites. This river basin is an important agriculture and cattle growing region with forest areas for paper pulp production. In the catchment of this river there are four dams for electricity production and two main artificial lakes which are water reservoirs to supply drinking water to more than 3 million people, and irrigation water for agriculture including maize and rice production. In the river basin, environmental remediation works were recently implemented especially at the milling tailings and at the major mine sites, which reduced radioactive drainage into the Mondego tributaries and thus into the Mondego river. Mine drainage and seepage from tailings are recuperated and treated in mine water treatment stations. Although, for example, in drainage from milling tailings at Urgeiriça, water may contain high concentrations of dissolved uranium ("2"3"8U), radium ("2"2"6Ra) and polonium ("2"1"0Po) at 35,700±1100, 1084±30, and 700±40 mBq/L, respectively, in the stream receiving discharges of treated water today radionuclide concentrations are orders of magnitude lower. The tributary streams that in the past received untreated mine discharges are today recovering and concentrations decreased to near natural levels. In the artificial lake of Aguieira dam, built on the Mondego River downstream all uranium sites, and where the main capture of water for human consumption is located, radionuclide concentrations were of 9.2±0.3 mBq/L, 17.7±1.9 mBq/L, and 5.3±0.2 mBq/L for uranium ("2"3"8U), radium ("2"2"6Ra) and polonium ("2"1"0Po), respectively. This water has been over the last years consistently in compliance with the EU drinking water quality standards

  20. Study on the mechanism of seepage flow in the grouting for multiple fractured model

    International Nuclear Information System (INIS)

    Nishigaki, Makoto; Mikake, Shin-ichiro

    2002-01-01

    The purpose of study is to improve the grouting method for fractured rock masses. In this paper, the results on the fundamental phenomenon for grasping the properties of grouting injection and seepage flow are discussed. The case of grouting stage is studied about the multiple hydraulic fractured apertures in the injected borehole. So the theory on the mechanism is constructed, and experiment is executed in order to verify the availability of the theory. From the results, it is shown that Bernoulli's law is able to prove the behavior of the grouting. And the theoretical evaluation is executed on the experiential procedure of the grouting. (author)

  1. A Basin Approach to a Hydrological Service Delivery System in the Amur River Basin

    Directory of Open Access Journals (Sweden)

    Sergei Borsch

    2018-03-01

    Full Text Available This paper presents the basin approach to the design, development, and operation of a hydrological forecasting and early warning system in a large transboundary river basin of high flood potential, where accurate, reliable, and timely available daily water-level and reservoir-inflow forecasts are essential for water-related economic and social activities (the Amur River basin case study. Key aspects of basin-scale system planning and implementation are considered, from choosing efficient forecast models and techniques, to developing and operating data-management procedures, to disseminating operational forecasts using web-GIS. The latter, making the relevant forecast data available in real time (via Internet, visual, and well interpretable, serves as a good tool for raising awareness of possible floods in a large region with transport and industrial hubs located alongside the Amur River (Khabarovsk, Komsomolsk-on-Amur.

  2. Petroleum migration pathways and charge concentration: A three-dimensional model

    Energy Technology Data Exchange (ETDEWEB)

    Hindle, A.D. [Anadarko Algeria Corp., Middlesex (United Kingdom)

    1997-09-01

    Petroleum migration pathways through a basin are determined by the three-dimensional distribution of discontinuous sealing surfaces, which are usually parallel to bedding. The petroleum migrates below the sealing surface, taking the structurally most advantageous route. The three-dimensional distribution of migration pathways within the petroleum system can be modeled on a personal computer using a program based on the parameters discussed in this paper. Application of the model to the Paris and Williston basins demonstrates that a good correlation between predicted pathways and discovered accumulations can be made using simple models. Pathways form a dense network overlying generating areas in the central parts of basins. Toward the basin margins these routes commonly become increasingly focused into discrete pathways by the sealing-surface morphologies. Eventually, these pathways may reach the surface as seepages. It is important to integrate surface outcrops of migration routes (surface seepages) into migration modeling. Deflection of the pathways from the structurally most advantageous route below the sealing surface may be caused by lateral sealing barriers due to faces variation in the carrier rock below the seal, fault juxtaposition, or cross-formational seals such as salt intrusions. Deflection of pathways also occurs where there are hydrodynamic conditions in response to topography-driven groundwater flow. Zones of vertical migration are associated with facies changes along the horizon of the sealing surface into a nonsealing facies, or juxtaposition to nonsealing strata by faults. Vertical migration from either normally or abnormally pressured strata is most likely to occur into normally or lesser pressured strata at intrabasinal highs where hydrocarbons can be stored and transferred at times of temporary seal rupture.

  3. Characterization of Preferential Ground-Water Seepage From a Chlorinated Hydrocarbon-Contaminated Aquifer to West Branch Canal Creek, Aberdeen Proving Ground, Maryland, 2002-04

    Science.gov (United States)

    Majcher, Emily H.; Phelan, Daniel J.; Lorah, Michelle M.; McGinty, Angela L.

    2007-01-01

    Wetlands act as natural transition zones between ground water and surface water, characterized by the complex interdependency of hydrology, chemical and physical properties, and biotic effects. Although field and laboratory demonstrations have shown efficient natural attenuation processes in the non-seep wetland areas and stream bottom sediments of West Branch Canal Creek, chlorinated volatile organic compounds are present in a freshwater tidal creek at Aberdeen Proving Ground, Maryland. Volatile organic compound concentrations in surface water indicate that in some areas of the wetland, preferential flow paths or seeps allow transport of organic compounds from the contaminated sand aquifer to the overlying surface water without undergoing natural attenuation. From 2002 through 2004, the U.S. Geological Survey, in cooperation with the Environmental Conservation and Restoration Division of the U.S. Army Garrison, Aberdeen Proving Ground, characterized preferential ground-water seepage as part of an ongoing investigation of contaminant distribution and natural attenuation processes in wetlands at this site. Seep areas were discrete and spatially consistent during thermal infrared surveys in 2002, 2003, and 2004 throughout West Branch Canal Creek wetlands. In these seep areas, temperature measurements in shallow pore water and sediment more closely resembled those in ground water than those in nearby surface water. Generally, pore water in seep areas contaminated with chlorinated volatile organic compounds had lower methane and greater volatile organic compound concentrations than pore water in non-seep wetland sediments. The volatile organic compounds detected in shallow pore water in seeps were spatially similar to the dominant volatile organic compounds in the underlying Canal Creek aquifer, with both parent and anaerobic daughter compounds detected. Seep locations characterized as focused seeps contained the highest concentrations of chlorinated parent compounds

  4. Rapid radiochemical procedures for a process support laboratory

    International Nuclear Information System (INIS)

    Beals, D.M.

    1998-01-01

    An on-site mobile laboratory has been installed near a groundwater treatment facility, and rapid analytical procedures have been deployed for determining sample activity in the process support laboratory. The required analyses to support the remediation project include gross alpha/, gross nonvolatile beta, 90 Sr, 99 Tc, 137 Cs and total Ra (226 + 228). The present mission of the Savannah River Site (SRS), a US Department of Energy nuclear production facility, is one of nuclear waste stabilization and of environmental restoration and remediation. Because of previous practices of disposing low-level radioactive waste to seepage basins, some of the groundwater under the SRS has become contaminated with radioactive species. A water treatment facility has been installed to remediate the groundwater below the old F and H areas' seepage basins. Groundwater is pumped from the contaminated aquifer through a series of filtration, ion exchange, and reverse osmosis steps and when cleaned is reinjected back into the aquifer. Samples are pulled from various points in the treatment facility to ensure that the process is working as designed. In order to minimize turnaround time for these analyses, a process control station (i.e., a mobile on-site laboratory) has been installed at the F area water treatment unit, and rapid radioanalytical procedures have been deployed

  5. Current vegetation characteristics within tree-kill zones of F- and H-Areas

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, E.A.; Irwin, J.E.

    1994-04-01

    Vegetation of two wetland areas previously adversely affected by outcropping groundwater was characterized to evaluate the type and extent of revegetation. When the damage first became evident in the late 1970s and early 1980s the areas were examined and described to try to establish the cause of the extensive tree mortality. The F- and H-Area seepage basins above the wetland areas received waste products from the separation areas beginning in 1955. The operation, estimated loading, and current status of the basins were summarized by Killian et al. Analysis of soil and water at the affected seeplines where the tree-kill was occurring confirmed that the surface water was strongly influenced by constituents of the F- and H-Area seepage basins. While no single cause of the forest mortality was defined, alterations in the hydrology and siltation patterns, pH changes, increased conductivity, and increased levels of sodium, nitrogen compounds, and aluminum were believed to be interacting to cause the mortality.

  6. Current vegetation characteristics within tree-kill zones of F- and H-Areas

    International Nuclear Information System (INIS)

    Nelson, E.A.; Irwin, J.E.

    1994-04-01

    Vegetation of two wetland areas previously adversely affected by outcropping groundwater was characterized to evaluate the type and extent of revegetation. When the damage first became evident in the late 1970s and early 1980s the areas were examined and described to try to establish the cause of the extensive tree mortality. The F- and H-Area seepage basins above the wetland areas received waste products from the separation areas beginning in 1955. The operation, estimated loading, and current status of the basins were summarized by Killian et al. Analysis of soil and water at the affected seeplines where the tree-kill was occurring confirmed that the surface water was strongly influenced by constituents of the F- and H-Area seepage basins. While no single cause of the forest mortality was defined, alterations in the hydrology and siltation patterns, pH changes, increased conductivity, and increased levels of sodium, nitrogen compounds, and aluminum were believed to be interacting to cause the mortality

  7. Development of electrical analogue model for studying seepage flow under hydraulic structures - case study: Sukkur barrage

    International Nuclear Information System (INIS)

    Gabriel, H.F.; Umar, I.A.; Khan, G.D.

    2003-01-01

    For the solution of groundwater problem many types of models are used, but electrical analogue model is preferred due to its close response with its prototype hydrological system. This model is easy to construct and is reusable. In the model voltage is correlated to groundwater head electric current to flow and capacitance to groundwater storage. The analogy of the model is derived based on Kirchhoffs law and Finite difference form of Laplace equation. The network is consisting of square and rectangular meshes. Scaling factor for voltage and resistors are selected. All the equipment needed for assembling the model are prepared. Terminal strips and their connectivity are checked. Calculated resistors with accurate values after cutting and molding are inserted in the terminal strips and desired section is completed. A network of resistors in X and Z direction is used to represent the aquifer. Two stabilized power supply are used to provide the electrical potential. The worst condition is maintained by supplying the maximum head at upstream and dry condition at downstream. After the development of the model conclusion derived shows that the model are in a position to express the groundwater potential for seepage distribution under the floor with high degree of accuracy. Moreover there is a very good proportion between sample and the actual prototype in existence. The actual model when tested by model show very clear results for the sheet pile in relation to floor length to control seepage or uplift pressure caused. The existence design of Sukkur barrage and its overestimation and underestimation with reference to their sheet pile have been specifically determined. (author)

  8. Geochemistry of Natural Gas Seepages in Boto Area, Bancak, Semarang, Central Java

    Directory of Open Access Journals (Sweden)

    Hendra Amijaya

    2017-03-01

    Full Text Available DOI: 10.17014/ijog.4.2.61-70Three seepage gas samples collected from Boto Area, Bancak, Semarang, Central Java, were studied to determine their chemical characteristics using GC and GC-IRMS methods. They are composed 53 - 85% of methane predominantly. However, gas seep Site 3 sample has the highest N2 compound and the lesser extent to the samples Site 2 and Site 1 respectively. The two hydrocarbon gas seeps (Site 1, 2, and Site 3 samples that are characterized by δ13C methane of -35.61‰ and -27.97‰, and values of δD methane of -112‰ and -109‰ respectively, are each isotopically distinct from all others suggesting, at least, they are derived from different maturity level. The Site 3 gas sample is suggested to be more mature than the others.

  9. The Ogaden Basin, Ethiopia: an underexplored sedimentary basin

    Energy Technology Data Exchange (ETDEWEB)

    Teitz, H.H.

    1991-01-01

    A brief article examines the Ogaden Basin in Ethiopia in terms of basin origin, basin fill and the hydrocarbon exploration history and results. The natural gas find in pre-Jurassic sandstones, which appears to contain substantial reserves, justifies continuing investigations in this largely underexplored basin. (UK).

  10. Umatilla Basin natural production monitoring and evaluation. Annual progress report, 1994--1995

    International Nuclear Information System (INIS)

    Contor, C.R.; Hoverson, E.; Kissner, P.; Volkman, J.

    1996-04-01

    This report summarizes the activities of the Umatilla Basin Natural Production Monitoring and Evaluation Project (UBNPME) from September 30, 1994 to September 29, 1995. This program was funded by Bonneville Power Administration and was managed under the Fisheries Program, Department of Natural Resources, Confederated Tribes of the Umatilla Indian Reservation. An estimated 36.7 km (22.6 miles) of stream habitat were inventoried on the Umatilla River, Moonshine, Mission, Cottonwood and Coonskin Creeks. A total of 384 of 3,652 (10.5%) habitat units were electrofished. The number of juvenile fish captured follows: 2,953 natural summer steelhead (including resident rainbow trout; Oncorhynchus mykiss), one hatchery steelhead, 341 natural chinook salmon (O. tshawytscha), 163 natural coho salmon (O. kisutch), five bull trout (Salvelinus confluentus), 185 mountain whitefish (Prosopium williamsoni), and six northern squawfish (Ptychoicheilus oregonensis). The expanded population estimate for the areas surveyed was 73,716 salmonids with a mean density of 0.38 fish/m 2 . Relative salmonid abundance, seasonal distribution and habitat utilization were monitored at index sites throughout the basin. During index site monitoring, the following species were collected in addition to those listed above: american shad (Alosa sapidissima), smallmouth bass (Micropterus dolomieu), carp (Cyprinus carpio) and chiselmouth (Acrocheilus alutaceus). Thirty-nine sites were electrofished during the spring and summer seasons, while 36 sites were sampled in the fall season. A study of the migration movements and homing requirements of adult salmonids in the Umatilla River was conducted during the 1994-95 return years. Radio telemetry was used to evaluate the movements of adult salmonids past diversion dams in the lower Umatilla River and to determine migrational movements of salmonids following upstream transport

  11. Sedimentary architecture of a Plio-Pleistocene proto-back-arc basin: Wanganui Basin, New Zealand

    Science.gov (United States)

    Proust, Jean-Noël; Lamarche, Geoffroy; Nodder, Scott; Kamp, Peter J. J.

    2005-11-01

    The sedimentary architecture of active margin basins, including back-arc basins, is known only from a few end-members that barely illustrate the natural diversity of such basins. Documenting more of these basins types is the key to refining our understanding of the tectonic evolution of continental margins. This paper documents the sedimentary architecture of an incipient back-arc basin 200 km behind the active Hikurangi subduction margin, North Island, New Zealand. The Wanganui Basin (WB) is a rapidly subsiding, Plio-Pleistocene sedimentary basin located at the southern termination of the extensional back-arc basin of the active Central Volcanic Region (TVZ). The WB is asymmetric with a steep, thrust-faulted, outer (arc-ward) margin and a gentle inner (craton-ward) margin. It contains a 4-km-thick succession of Plio-Pleistocene sediments, mostly lying offshore, composed of shelf platform sediments. It lacks the late molasse-like deposits derived from erosion of a subaerial volcanic arc and basement observed in classical back-arc basins. Detailed seismic stratigraphic interpretations from an extensive offshore seismic reflection data grid show that the sediment fill comprises two basin-scale mega-sequences: (1) a Pliocene (3.8 to 1.35 Ma), sub-parallel, regressive "pre-growth" sequence that overtops the uplifted craton-ward margin above the reverse Taranaki Fault, and (2) a Pleistocene (1.35 Ma to present), divergent, transgressive, "syn-growth" sequence that onlaps: (i) the craton-ward high to the west, and (ii) uplifted basement blocks associated with the high-angle reverse faults of the arc-ward margin to the east. Along strike, the sediments offlap first progressively southward (mega-sequence 1) and then southeastward (mega-sequence 2), with sediment transport funnelled between the craton- and arc-ward highs, towards the Hikurangi Trough through the Cook Strait. The change in offlap direction corresponds to the onset of arc-ward thrust faulting and the rise of

  12. Impact of Quaternary Climate on Seepage at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    J.F. Whelan; J.B. Paces; L.A. Neymark; A.K. Schmitt; M. Grove

    2006-01-01

    Uranium-series ages, oxygen-isotopic compositions, and uranium contents were determined in outer growth layers of opal and calcite from 0.5- to 3-centimeter-thick mineral coatings hosted by lithophysal cavities in the unsaturated zone at Yucca Mountain, Nevada, the proposed site of a permanent repository for high-level radioactive waste. Micrometer-scale growth layering in the minerals was imaged using a cathodoluminescence detector on a scanning electron microscope. Determinations of the chemistry, ages, and delta oxygen-18 values of the growth layers were conducted by electron microprobe analysis and secondary ion mass spectrometry techniques at spatial resolutions of 1 to about 20 micrometers ((micro)m) and 25 to 40 micrometers, respectively. Growth rates for the last 300 thousand years (k.y.) calculated from about 300 new high-resolution uranium-series ages range from approximately 0.5 to 1.5 (micro)m/k.y. for 1- to 3-centimeter-thick coatings, whereas coatings less than about I-centimeter-thick have growth rates less than 0.5 (micro)m/k.y. At the depth of the proposed repository, correlations of uranium concentration and delta oxygen-18 values with regional climate records indicate that unsaturated zone percolation and seepage water chemistries have responded to changes in climate during the last several hundred thousand years

  13. Iodine-129 in the environment of a nuclear fuel reprocessing plant by neutron activation analysis

    International Nuclear Information System (INIS)

    Anderson, T.J.

    1978-01-01

    129 I has been analyzed in both aqueous and soil samples to characterize the environmental impact of the Savannah River Plant (SRP) reprocessing operations. 129 I was quantified by a neutron activation procedure with γ-ray spectrometric detection [Ge(Li)]. For many samples, natural iodine ( 127 I) was also quantified. A wide range of samples can be accommodated by a combustion-based preirradiation isolation technique. 129 I amounts as low as 3.8 fCi can be determined with counting times of less than 30 minutes (s/sub rel/ = 10%). Deposition of 129 I in the environment via aqueous and airborne emissions has been studied. Data from analysis of seepage basin contents, spring water, on-plant streams, and the Savannah River show that 129 I from the seepage basins migrates easily through the soil with the groundwater, eventually reaching the Savannah River. Annual aqueous release rates were estimated to be 16 to 27 mCi/year. Data from analysis of soils from distances up to 159 km from SRP show above background levels of 129 I in both the minimum and maximum airborne transport directions. The soil results are compared with a wind dispersion model. The vertical distribution of 129 I in the soil was determined to a depth of 61 cm

  14. Non-Darcy Flow Experiments of Water Seepage through Rough-Walled Rock Fractures

    Directory of Open Access Journals (Sweden)

    Xiao-dong Ni

    2018-01-01

    Full Text Available The knowledge of flow phenomena in fractured rocks is very important for groundwater-resources management in hydrogeological engineering. The most commonly used tool to approximate the non-Darcy behavior of the flow velocity is the well-known Forchheimer equation, deploying the “inertial” coefficient β that can be estimated experimentally. Unfortunately, the factor of roughness is imperfectly considered in the literature. In order to do this, we designed and manufactured a seepage apparatus that can provide different roughness and aperture in the test; the rough fracture surface is established combining JRC and 3D printing technology. A series of hydraulic tests covering various flows were performed. Experimental data suggest that Forchheimer coefficients are to some extent affected by roughness and aperture. At last, favorable semiempirical Forchheimer equation which can consider fracture aperture and roughness was firstly derived. It is believed that such studies will be quite useful in identifying the limits of applicability of the well-known “cubic law,” in further improving theoretical/numerical models associated with fluid flow through a rough fracture.

  15. Integrated Hydrographical Basin Management. Study Case - Crasna River Basin

    Science.gov (United States)

    Visescu, Mircea; Beilicci, Erika; Beilicci, Robert

    2017-10-01

    Hydrographical basins are important from hydrological, economic and ecological points of view. They receive and channel the runoff from rainfall and snowmelt which, when adequate managed, can provide fresh water necessary for water supply, irrigation, food industry, animal husbandry, hydrotechnical arrangements and recreation. Hydrographical basin planning and management follows the efficient use of available water resources in order to satisfy environmental, economic and social necessities and constraints. This can be facilitated by a decision support system that links hydrological, meteorological, engineering, water quality, agriculture, environmental, and other information in an integrated framework. In the last few decades different modelling tools for resolving problems regarding water quantity and quality were developed, respectively water resources management. Watershed models have been developed to the understanding of water cycle and pollution dynamics, and used to evaluate the impacts of hydrotechnical arrangements and land use management options on water quantity, quality, mitigation measures and possible global changes. Models have been used for planning monitoring network and to develop plans for intervention in case of hydrological disasters: floods, flash floods, drought and pollution. MIKE HYDRO Basin is a multi-purpose, map-centric decision support tool for integrated hydrographical basin analysis, planning and management. MIKE HYDRO Basin is designed for analyzing water sharing issues at international, national and local hydrographical basin level. MIKE HYDRO Basin uses a simplified mathematical representation of the hydrographical basin including the configuration of river and reservoir systems, catchment hydrology and existing and potential water user schemes with their various demands including a rigorous irrigation scheme module. This paper analyzes the importance and principles of integrated hydrographical basin management and develop a case

  16. Geochemistry of crude oils, seepage oils and source rocks from Belize and Guatemala

    DEFF Research Database (Denmark)

    Petersen, H.I.; Holland, B.; Nytoft, H.P.

    2012-01-01

    This study reviews the stratigraphy and the poorly documented petroleum geology of the Belize-Guatemala area in northern Central America. Guatemala is divided by the east-west trending La Libertad arch into the North and South Petén Basins. The arch is the westward continuation of the Maya...... generated from source rocks with similar thermal maturities. The crude oils were generated from marine carbonate source rocks and could be divided into three groups: Group 1 oils come from the North Petén Basin (Guatemala) and the western part of the Corozal Basin (Belize), and have a typical carbonate...

  17. Development and evaluation of an ultrasonic ground water seepage meter.

    Science.gov (United States)

    Paulsen, R J; Smith, C F; O'Rourke, D; Wong, T F

    2001-01-01

    Submarine ground water discharge can influence significantly the near-shore transport and flux of chemicals into the oceans. Quantification of the sources and rates of such discharge requires a ground water seepage meter that provides continuous measurements at high resolution over an extended period of time. An ultrasonic flowmeter has been adapted for such measurements in the submarine environment. Connected to a steel collection funnel, the meter houses two piezoelectric transducers mounted at opposite ends of a cylindrical flow tube. By monitoring the perturbations of fluid flow on the propagation of sound waves inside the flow tube, the ultrasonic meter can measure both forward and reverse fluid flows in real time. Laboratory and field calibrations show that the ultrasonic meter can resolve ground water discharges on the order of 0.1 microm/sec, and it is sufficiently robust for deployment in the field for several days. Data from West Neck Bay, Shelter Island, New York, elucidate the temporal and spatial heterogeneity of submarine ground water discharge and its interplay with tidal loading. A negative correlation between the discharge and tidal elevation was generally observed. A methodology was also developed whereby data for the sound velocity as a function of temperature can be used to infer the salinity and source of the submarine discharge. Independent measurements of electrical conductance were performed to validate this methodology.

  18. Seepage patterns of Diuron in a ditch bed during a sequence of flood events

    International Nuclear Information System (INIS)

    Dages, C.; Samouëlian, A.; Negro, S.; Storck, V.; Huttel, O.; Voltz, M.

    2015-01-01

    Although ditches limit surface water contamination, groundwater recharge through ditches in Mediterranean catchments may result in groundwater contamination. We analysed the dynamics of pesticide percolation in ditches by conducting an original lab experiment that mimicked the successive percolation processes that occur during a flood season. Nine successive percolation events were operated on an undisturbed soil column collected from a ditch bed. The infiltrating water was doped with 14 C-Diuron at concentrations that were chosen to decrease between the events so as to correspond to values observed during actual flood events. The water and solute fluxes were monitored during each event, and the final extractable and non-extractable Diuron residues in the column were determined. Two main observations were made. First, a high leaching potential was observed through the ditch bed over a succession of infiltrating flood events, with 58.9% of the infiltrated Diuron and its metabolites leaching. Second, compared with the contamination of surface water circulating in the ditches, the contamination of seepage water exhibited smaller peak values and persisted much longer because of the desorption of Diuron residues stored in the ditch bed. Thus, ditches serve as buffering zones between surface and groundwater. However, compared with field plots, ditches appear to be a preferential location for the percolation of pesticides into groundwater at the catchment scale. - Highlights: • Diuron percolation in a ditch bed during flood events was mimicked in a column setup. • Diuron percolation can represent up to 50% of the infiltrated Diuron. • The ditch bed exhibits a high buffering capacity due to its high sorption properties. • Contamination period of percolation water lasts longer than that of infiltrating water. • Diuron residues stored in ditch bed move deeper than in field topsoils.

  19. Seepage patterns of Diuron in a ditch bed during a sequence of flood events

    Energy Technology Data Exchange (ETDEWEB)

    Dages, C., E-mail: cecile.dages@supagro.inra.fr; Samouëlian, A.; Negro, S.; Storck, V.; Huttel, O.; Voltz, M.

    2015-12-15

    Although ditches limit surface water contamination, groundwater recharge through ditches in Mediterranean catchments may result in groundwater contamination. We analysed the dynamics of pesticide percolation in ditches by conducting an original lab experiment that mimicked the successive percolation processes that occur during a flood season. Nine successive percolation events were operated on an undisturbed soil column collected from a ditch bed. The infiltrating water was doped with {sup 14}C-Diuron at concentrations that were chosen to decrease between the events so as to correspond to values observed during actual flood events. The water and solute fluxes were monitored during each event, and the final extractable and non-extractable Diuron residues in the column were determined. Two main observations were made. First, a high leaching potential was observed through the ditch bed over a succession of infiltrating flood events, with 58.9% of the infiltrated Diuron and its metabolites leaching. Second, compared with the contamination of surface water circulating in the ditches, the contamination of seepage water exhibited smaller peak values and persisted much longer because of the desorption of Diuron residues stored in the ditch bed. Thus, ditches serve as buffering zones between surface and groundwater. However, compared with field plots, ditches appear to be a preferential location for the percolation of pesticides into groundwater at the catchment scale. - Highlights: • Diuron percolation in a ditch bed during flood events was mimicked in a column setup. • Diuron percolation can represent up to 50% of the infiltrated Diuron. • The ditch bed exhibits a high buffering capacity due to its high sorption properties. • Contamination period of percolation water lasts longer than that of infiltrating water. • Diuron residues stored in ditch bed move deeper than in field topsoils.

  20. A GIS-based, confined aquifer, hypothetical model of ground-water seepage into a former mining open pit

    International Nuclear Information System (INIS)

    Salama, A; Negeed, E.R.

    2010-01-01

    Groundwater seepage into a former mining site in Egypt is proposed for simulation. This site was used for basalt extraction. After the mining activities had stopped a large open pit was left over and groundwater seeped into the pit forming a lake. The pit has a dimension of approximately 1200 x 600 x 30 m. Because of the lack of field data, several scenarios may be hypothesized to explain the filling of these open pits with water. In this paper, one of these scenarios is studied. It is suggested that this water comes from an underneath confined aquifer. Through fractures in the host rock, water seeped upwards into the open pit. To estimate the rate at which water seeps into the lake, numerical study based on the finite element method is performed. Firstly, geo-referencing of the site was performed using GIS. The boundary of the lake was then digitized and elevation contours was defined. These data was then imported into grid-builder software to generate a two-dimensional triangular mesh which was then used by hydro-geosphere software to build the three-dimensional mesh and solve the problem. It was found that the set of discrete fractures was insufficient to fill the lake in the time span that was actually elapsed to fill up the lake which is on the order of two to three years.

  1. Results of The Tritium Survey of Fourmile Branch and its Seeplines in the F- and H-Areas of SRS: March 1996

    International Nuclear Information System (INIS)

    Koch, J. II; Dixon, K.L.

    1996-10-01

    The Environmental Sciences Section (ESS) of the Savannah River Technology Center (SRTC) conducted a quarterly monitoring program of the Fourmile Branch (FMB) stream and its associated seepline located down gradient from the F- and H-Area Seepage Basins beginning May 1992 and ending in May 1995. The quarterly tritium survey has been changed to a semi-annual schedule, and this report details the results of the first event in FY96. The primary focus of this program is to measure and track changes in tritium levels. However, specific conductivity and pH were also measured and tracked. The measurements from this survey (March 1996) exhibited similar tritium levels, conductivity measurements, and pH values to data from the previous quarterly tritium surveys. The overall results of the tritium survey and stream monitoring data (Looney et al., 1993) indicate that the tritium plume resulting from the past operation of the seepage basins continues to flush from the seeplines and wetlands to Fourmile Branch

  2. The Minorca Basin: a buffer zone between the Valencia and Liguro-Provençal Basins (NW Mediterranean Sea)

    Science.gov (United States)

    Pellen, Romain; Aslanian, Daniel; Rabineau, Marina; Leroux, Estelle; Gorini, Christian; Silenziario, Carmine; Blanpied, Christian; Rubino, Jean-Loup

    2017-04-01

    The present-day compartmented Mediterranean physiography is inherited from the last 250 Ma kinematic plate evolution (Eurasian, Africa, Iberic and Nubia plates) which implied the formation of orogenic chains, polyphased basins, and morphological - geodynamic thresholds. The interactions between these entities are strongly debated in the North-Western Mediterranean area. Several Neogene reconstructions have been proposed for the Valencia basin depending of the basin segmentation where each model imply a different subsidence, sedimentary, and palaeo-environmental evolution. Our study propose a new kinematic model for the Valencia Basin (VB) that encompasses the sedimentary infill, vertical movement and basin segmentation. Detailed analyses of seismic profiles and boreholes in the VB reveal a differentiated basin, the Minorca Basin (MB), lying between the old Mesozoic Valencia Basin sensu strico (VBss) and the young Oligocene Liguro-Provencal Basin (LPB) (Pellen et al., 2016). The relationship between these basins is shown through the correlation of four Miocene-to-present-day megasequences. The Central and North Balearic Fracture Zones (CFZ and NBFZ) that border the MB represent two morphological and geodynamical thresholds that created an accommodation in steps between the three domains. Little to no horizontal Neogene movements have been found for the Ibiza and Majorca Islands and imply a vertical "sag" subsidence. In contrast, the counterclockwise movement of the Corso-Sardinian blocks induced a counterclockwise movement of the Minorca block towards the SE along the CFZ and NBFZ, during the exhumation of lower continental crust in the LPB. The South-Eastward Minorca block translation stops when the first atypical oceanic crust occurs. The influence of the Neogene Betic compressional phase is thus limited to the VBss on the basis of a different MB origin. This new understanding places the AlKaPeCa blocks northeastward of the present-day Alboran Area. Both NW-SE and

  3. Hurricane Impact on Seepage Water in Larga Cave, Puerto Rico

    Science.gov (United States)

    Vieten, Rolf; Warken, Sophie; Winter, Amos; Schröder-Ritzrau, Andrea; Scholz, Denis; Spötl, Christoph

    2018-03-01

    Hurricane-induced rainfall over Puerto Rico has characteristic δ18O values which are more negative than local rainfall events. Thus, hurricanes may be recorded in speleothems from Larga cave, Puerto Rico, as characteristic oxygen isotope excursions. Samples of 84 local rainfall events between 2012 and 2013 ranged from -6.2 to +0.3‰, whereas nine rainfall samples belonging to a rainband of hurricane Isaac (23-24 August 2012) ranged from -11.8 to -7.1‰. Cave monitoring covered the hurricane season of 2014 and investigated the impact of hurricane rainfall on drip water chemistry. δ18O values were measured in cumulative monthly rainwater samples above the cave. Inside the cave, δ18O values of instantaneous drip water samples were analyzed and drip rates were recorded at six drip sites. Most effective recharge appears to occur during the wet months (April-May and August-November). δ18O values of instantaneous drip water samples ranged from -3.5 to -2.4‰. In April 2014 and April 2015 some drip sites showed more negative δ18O values than the effective rainfall (-2.9‰), implying an influence of hurricane rainfall reaching the cave via stratified seepage flow months to years after the event. Speleothems from these drip sites in Larga cave have a high potential for paleotempestology studies.

  4. Racismo e violação aos direitos humanos pela internet: estudo da Lei nº 7.716/89

    OpenAIRE

    Celso Eduardo Santos de Melo

    2010-01-01

    Este trabalho tem como objeto específico o estudo da Lei nº 7.716/89, sobretudo o artigo 20, relativo às condutas tipificadas como crime de racismo quando praticadas utilizando-se como meio de publicação a Internet. Diante desse desafio, foi preciso verificar o histórico da questão das relações raciais no Brasil, bem como as previsões atuais de proteção do Estado contra as formas de discriminação racial. Em vista do meio utilizado na prática de condutas delituosas, a internet, foi necessário ...

  5. Description of the Panel Mine tailings area Rio Algom Ltd., Elliot Lake, Ontario, Canada

    International Nuclear Information System (INIS)

    Pullen, P.F.; Davis, J.B.

    1982-01-01

    The geomorphological setting of the Panel Mine tailings management area is described in relation to the geology of the Canadian Shield subject to recent glaciation and subsequent weathering and erosion in a humid climate with temperature extremes. For the deposition of uranium tailings a topographic low is chosen that is surrounded by bedrock with a low water permeability. This latter is evaluated by a detailed geological investigation and by drilling to investigate the relative pemeability of suspected seepage paths. It is estimated that seepage from the basin used will be less than one litre per second. Monitor wells have been established to determine the quality of the groundwater flows

  6. BasinVis 1.0: A MATLAB®-based program for sedimentary basin subsidence analysis and visualization

    Science.gov (United States)

    Lee, Eun Young; Novotny, Johannes; Wagreich, Michael

    2016-06-01

    Stratigraphic and structural mapping is important to understand the internal structure of sedimentary basins. Subsidence analysis provides significant insights for basin evolution. We designed a new software package to process and visualize stratigraphic setting and subsidence evolution of sedimentary basins from well data. BasinVis 1.0 is implemented in MATLAB®, a multi-paradigm numerical computing environment, and employs two numerical methods: interpolation and subsidence analysis. Five different interpolation methods (linear, natural, cubic spline, Kriging, and thin-plate spline) are provided in this program for surface modeling. The subsidence analysis consists of decompaction and backstripping techniques. BasinVis 1.0 incorporates five main processing steps; (1) setup (study area and stratigraphic units), (2) loading well data, (3) stratigraphic setting visualization, (4) subsidence parameter input, and (5) subsidence analysis and visualization. For in-depth analysis, our software provides cross-section and dip-slip fault backstripping tools. The graphical user interface guides users through the workflow and provides tools to analyze and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the results using the full range of available plot options in MATLAB. We demonstrate all functions in a case study of Miocene sediment in the central Vienna Basin.

  7. Organic geochemistry of petroleum seepages within the Jurassic Bencliff Grit, Osmington Mills, Dorset, UK

    Energy Technology Data Exchange (ETDEWEB)

    Watson, D.F.; Farrimond, P. [University of Newcastle upon Tyne (United Kingdom). Fossil Fuels and Environmental Geochemistry; Hindle, A.D. [Egdon Resources (UK) Ltd., Odiham (United Kingdom)

    2000-11-01

    Occurrences of oil within the Bencliff Grit at Osmington Mills were studied through an integration of organic geochemistry and a consideration of the geological setting. Oil-stained sandstones dominate the cliff outcrop with localized regions of particularly concentrated oil impregnation. A second 'live' seep of oil occurs where the Bencliff Grit beds pass below high tide level at Bran Point. Organic geochemical analyses showed both oils to be at least moderately biodegraded, with the oils in the cliff outcrop showing enrichment in polar constituents compared with the active seep. Multivariate statistical analysis of the molecular composition identified an enrichment in diasterane biomarkers in the oils of the live seep; this difference is ascribed to source and/or maturity differences. The oil within the outcrop is considered to represent the residual staining of an unroofed oil field, whilst the live seepage at Bran Point represents a migration pathway towards the eroded anticline. (Author)

  8. Influence of stress-induced deformations on observed water flow in fractures at the Climax granitic stock

    International Nuclear Information System (INIS)

    Wilder, D.G.

    1987-06-01

    Three examples of stress-induced displacement influence on fracture-dominated hydrology were noted in drifts 1400 ft below surface in granite. Seepage into drifts was limited to portions of shears near a fault zone. No water entered the drifts from the fault itself, although its orientation relative to Basin and Range extension is favorable for fracture opening. Localization of seepage appears to result from excavation block motion that increased apertures of the shear zones in contrast to the fault where asperities had been destroyed by earlier shearing thus minimizing aperture increases. Seepage was also noted, in an adjoining drift, from a set of shallow-dip healed fractures that intersected the rib, and from vertical fractures that increased the crown. The restricted location of this seepage apparently was a result of shear opening of the joints that occurred because of cantilevered support of tabular rock between joints. Interpretation of paleostresses based on joint chronologies and orientations indicates that sets subjected to shear stresses at a time when normal stresses were low contained mineral infilling. Sets subjected to shear stresses at a time when the normal stresses were significant had minimal mineral infilling. 8 refs., 7 figs

  9. Petroleum systems in rift basinsa collective approach in South-east Asian basins.

    NARCIS (Netherlands)

    Doust, H.; Sumner, D.

    2007-01-01

    This paper synthesizes some of the main conclusions reached in a recent regional review of the Tertiary basins of Southeast Asia, carried out by Shell. Four distinctive types of petroleum systems, correlating with the four main stages of basin evolution (early to late syn-rift and early to late

  10. The Agost Basin (Betic Cordillera, Alicante province, Spain): a pull-apart basin involving salt tectonics

    Science.gov (United States)

    Martín-Martín, Manuel; Estévez, Antonio; Martín-Rojas, Ivan; Guerrera, Francesco; Alcalá, Francisco J.; Serrano, Francisco; Tramontana, Mario

    2018-03-01

    The Agost Basin is characterized by a Miocene-Quaternary shallow marine and continental infilling controlled by the evolution of several curvilinear faults involving salt tectonics derived from Triassic rocks. From the Serravallian on, the area experienced a horizontal maximum compression with a rotation of the maximum stress axis from E-W to N-S. The resulting deformation gave rise to a strike-slip fault whose evolution is characterized progressively by three stages: (1) stepover/releasing bend with a dextral motion of blocks; (2) very close to pure horizontal compression; and (3) restraining bend with a sinistral movement of blocks. In particular, after an incipient fracturing stage, faults generated a pull-apart basin with terraced sidewall fault and graben subzones developed in the context of a dextral stepover during the lower part of late Miocene p.p. The occurrence of Triassic shales and evaporites played a fundamental role in the tectonic evolution of the study area. The salty material flowed along faults during this stage generating salt walls in root zones and salt push-up structures at the surface. During the purely compressive stage (middle part of late Miocene p.p.) the salt walls were squeezed to form extrusive mushroom-like structures. The large amount of clayish and salty material that surfaced was rapidly eroded and deposited into the basin, generating prograding fan clinoforms. The occurrence of shales and evaporites (both in the margins of the basin and in the proper infilling) favored folding of basin deposits, faulting, and the formation of rising blocks. Later, in the last stage (upper part of late Miocene p.p.), the area was affected by sinistral restraining conditions and faults must have bent to their current shape. The progressive folding of the basin and deformation of margins changed the supply points and finally caused the end of deposition and the beginning of the current erosive systems. On the basis of the interdisciplinary results

  11. Semi-annual sampling of Fourmile Branch and its seeplines in the F and H Areas of SRS: July 1992

    International Nuclear Information System (INIS)

    Dixon, K.L.; Rogers, V.A.

    1994-04-01

    In July 1992, water samples were collected from Fourmile Branch (FMB) and its seeplines in the vicinity of the F and H-Area seepage basins. The samples were collected from five seepline locations in F Area, five seepline locations in H Area, and three stream locations on FMB. The sampling event was the first in a series of three semi-annual sampling event was the first in a series of three semi-annual sampling events aimed at characterizing the shallow groundwater outcropping into FMB and its wetlands. In the past, this groundwater has been shown to contain contaminants migrating from the F- and H-Area seepage basins. The samples were analyzed for Appendix 9 metals, various radionuclides, selected volatile compounds, and selected inorganic constituents and parameters. Results from the July 1992 sampling event suggest that the seeplines in both F and H Areas and FMB continue to be influenced by contaminants migrating from the F- and H-Area seepage basins. However, when compared to 1989 measurements, the concentrations of most of the constituents have declined. Contaminant concentration measured in July 1992 were compared to primary drinking water standards (PDWS), secondary drinking water standards (SDWS), and maximum contaminant levels (MCL) enforceable in 1993. Results were also compared to 1989 measurements at corresponding sampling locations and to background samples collected as part of the July 1992 sampling event. Using two different statistical tests, concentrations of selected F- and H-Area seepline analytes were compared to background samples. These tests were designed to detect if concentrations of contaminants along the F- and H-Area seeplines were greater than background concentrations

  12. Comparative Research on River Basin Management in the Sagami River Basin (Japan and the Muda River Basin (Malaysia

    Directory of Open Access Journals (Sweden)

    Lay Mei Sim

    2018-05-01

    Full Text Available In the world, river basins often interwoven into two or more states or prefectures and because of that, disputes over water are common. Nevertheless, not all shared river basins are associated with water conflicts. Rivers in Japan and Malaysia play a significant role in regional economic development. They also play a significant role as water sources for industrial, domestic, agricultural, aquaculture, hydroelectric power generation, and the environment. The research aim is to determine the similarities and differences between the Sagami and Muda River Basins in order to have a better understanding of the governance needed for effectively implementing the lessons drawn from the Sagami River Basin for improving the management of the Muda River Basin in Malaysia. This research adopts qualitative and quantitative approaches. Semi-structured interviews were held with the key stakeholders from both basins and show that Japan has endeavored to present policy efforts to accommodate the innovative approaches in the management of their water resources, including the establishment of a river basin council. In Malaysia, there is little or no stakeholder involvement in the Muda River Basin, and the water resource management is not holistic and is not integrated as it should be. Besides that, there is little or no Integrated Resources Water Management, a pre-requisite for sustainable water resources. The results from this comparative study concluded that full support and participation from public stakeholders (meaning the non-government and non-private sector stakeholders is vital for achieving sustainable water use in the Muda River Basin. Integrated Water Resources Management (IWRM approaches such as the introduction of payments for ecosystems services and the development of river basin organization in the Muda River Basin should take place in the spirit of political willingness.

  13. The annual pattern of sap flow in two Eucalyptus species ...

    African Journals Online (AJOL)

    Several hundred mine tailings dams occur in the Witwatersrand Basin Goldfields in central South Africa. Seepage of acid mine drainage (AMD) from these unlined structures is widespread, and a variety of contaminants is released into soil and groundwater. The 'Mine Woodlands Project' is aimed at evaluating the use of ...

  14. A proposal for an administrative set up of river basin management in the Sittaung River Basin

    OpenAIRE

    Tun, Zaw Lwin; Ni, Bo; Tun, Sein; Nesheim, Ingrid

    2016-01-01

    The purpose of this report is to present a proposal for how an administrative approach based on River Basin Management can be implemented in Myanmar. The Sittaung River Basin has been used as an example area to investigate how the basin can be administered according to the IWRM principles of cooperation between the different sectors and the administrative units, including stakeholder involvement. Ministry of Natural Resource and Environmental Conservation, Myanmar Norwegian Ministry of For...

  15. Correlation of Self Potential and Ground Magnetic Survey Techniques to Investigate Fluid Seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia

    OpenAIRE

    Tajudeen O. Adeeko; Nordiana M. Muztaza; Taqiuddin M. Zakaria; Nurina Ismail

    2018-01-01

    One of the substantial of geophysics is to investigate the subsurface condition of the earth (groundwater) using appropriate geophysical techniques. In this research the correlation of self potential (SP) and ground magnetic methods was used to investigate fluid seepage in Archaeological site, Sungai Batu, Lembah Bujang, Kedah, Malaysia. Self-potential method was used to determine flow of water, and Ground magnetic method was used to find object that can influence the result of self potential...

  16. Basin Analysis and Petroleum System Characterisation of Western Bredasdorp Basin, Southern Offshore of South Africa: Insights from a 3d Crust-Scale Basin Model - (Phase 1)

    Science.gov (United States)

    Sonibare, W. A.; Scheck-Wenderoth, M.; Sippel, J.; Mikeš, D.

    2012-04-01

    In recent years, construction of 3D geological models and their subsequent upscaling for reservoir simulation has become an important tool within the oil industry for managing hydrocarbon reservoirs and increasing recovery rate. Incorporating petroleum system elements (i.e. source, reservoir and trap) into these models is a relatively new concept that seems very promising to play/prospect risk assessment and reservoir characterisation alike. However, yet to be fully integrated into this multi-disciplinary modelling approach are the qualitative and quantitative impacts of crust-scale basin dynamics on the observed basin-fill architecture and geometries. The focus of this study i.e. Western Bredasdorp Basin constitutes the extreme western section of the larger Bredasdorp sub-basin, which is the westernmost depocentre of the four southern Africa offshore sub-basins (others being Pletmos, Gamtoos and Algoa). These basins, which appear to be initiated by volcanically influenced continental rifting and break-up related to passive margin evolution (during the Mid-Late Jurassic to latest Valanginian), remain previously unstudied for crust-scale basin margin evolution, and particularly in terms of relating deep crustal processes to depo-system reconstruction and petroleum system evolution. Seismic interpretation of 42 2D seismic-reflection profiles forms the basis for maps of 6 stratigraphic horizons which record the syn-rift to post-rift (i.e. early drift and late drift to present-day seafloor) successions. In addition to this established seismic markers, high quality seismic profiles have shown evidence for a pre-rift sequence (i.e. older than Late Jurassic >130 Ma). The first goal of this study is the construction of a 3D gravity-constrained, crust-scale basin model from integration of seismics, well data and cores. This basin model is constructed using GMS (in-house GFZ Geo-Modelling Software) while testing its consistency with the gravity field is performed using IGMAS

  17. Drainage basins features and hydrological behaviour river Minateda basin

    International Nuclear Information System (INIS)

    Alonso-Sarria, F.

    1991-01-01

    Nine basin variables (shape, size and topology) have been analyzed in four small basins with non-permanent run off (SE of Spain). These geomorphological variables have been selected for their high correlation with the Instantaneous unit hydrograph parameters. It is shown that the variables can change from one small basin to another within a very short area; because of it, generalizations about the behaviour of the run off are not possible. In conclusion, it is stated that the variations in geomorphological aspects between different basins, caused mainly by geological constraints, are a very important factor to be controlled in a study of geoecological change derived from climatic change

  18. RESERVES IN WESTERN BASINS PART IV: WIND RIVER BASIN

    Energy Technology Data Exchange (ETDEWEB)

    Robert Caldwell

    1998-04-01

    Vast quantities of natural gas are entrapped within various tight formations in the Rocky Mountain area. This report seeks to quantify what proportion of that resource can be considered recoverable under today's technological and economic conditions and discusses factors controlling recovery. The ultimate goal of this project is to encourage development of tight gas reserves by industry through reducing the technical and economic risks of locating, drilling and completing commercial tight gas wells. This report is the fourth in a series and focuses on the Wind River Basin located in west central Wyoming. The first three reports presented analyses of the tight gas reserves and resources in the Greater Green River Basin (Scotia, 1993), Piceance Basin (Scotia, 1995) and the Uinta Basin (Scotia, 1995). Since each report is a stand-alone document, duplication of language will exist where common aspects are discussed. This study, and the previous three, describe basin-centered gas deposits (Masters, 1979) which contain vast quantities of natural gas entrapped in low permeability (tight), overpressured sandstones occupying a central basin location. Such deposits are generally continuous and are not conventionally trapped by a structural or stratigraphic seal. Rather, the tight character of the reservoirs prevents rapid migration of the gas, and where rates of gas generation exceed rates of escape, an overpressured basin-centered gas deposit results (Spencer, 1987). Since the temperature is a primary controlling factor for the onset and rate of gas generation, these deposits exist in the deeper, central parts of a basin where temperatures generally exceed 200 F and drill depths exceed 8,000 feet. The abbreviation OPT (overpressured tight) is used when referring to sandstone reservoirs that comprise the basin-centered gas deposit. Because the gas resources trapped in this setting are so large, they represent an important source of future gas supply, prompting studies

  19. Valley formation by groundwater seepage, pressurized groundwater outbursts and crater-lake overflow in flume experiments with implications for Mars

    Science.gov (United States)

    Marra, Wouter A.; Braat, Lisanne; Baar, Anne W.; Kleinhans, Maarten G.

    2014-04-01

    Remains of fluvial valleys on Mars reveal the former presence of water on the surface. However, the source of water and the hydrological setting is not always clear, especially in types of valleys that are rare on Earth and where we have limited knowledge of the processes involved. We investigated three hydrological scenarios for valley formation on Mars: hydrostatic groundwater seepage, release of pressurized groundwater and crater-lake overflow. Using physical modeling in laboratory experiments and numerical hydrological modeling we quantitatively studied the morphological development and processes involved in channel formation that result from these different sources of water in unconsolidated sediment. Our results show that valleys emerging from seeping groundwater by headward erosion form relatively slowly as fluvial transport takes place in a channel much smaller than the valley. Pressurized groundwater release forms a characteristic source area at the channel head by fluidization processes. This head consist of a pit in case of superlithostatic pressure and may feature small radial channels and collapse features. Valleys emerging from a crater-lake overflow event develop quickly in a run-away process of rim erosion and discharge increase. The valley head at the crater outflow point has a converging fan shape, and the rapid incision of the rim leaves terraces and collapse features. Morphological elements observed in the experiments can help in identifying the formative processes on Mars, when considerations of experimental scaling and lithological characteristics of the martian surface are taken into account. These morphological features might reveal the associated hydrological settings and formative timescales of a valley. An estimate of formative timescale from sediment transport is best based on the final channel dimensions for groundwater seepage valleys and on the valley dimensions for pressurized groundwater release and crater-lake overflow valleys. Our

  20. Authigenic carbonates from newly discovered active cold seeps on the northwestern slope of the South China Sea: Constraints on fluid sources, formation environments, and seepage dynamics

    Science.gov (United States)

    Liang, Qianyong; Hu, Yu; Feng, Dong; Peckmann, Jörn; Chen, Linying; Yang, Shengxiong; Liang, Jinqiang; Tao, Jun; Chen, Duofu

    2017-06-01

    Authigenic carbonates recovered from two newly discovered active cold seeps on the northwestern slope of the South China Sea have been studied using petrography, mineralogy, stable carbon and oxygen isotopic, as well as trace element compositions, together with AMS 14C ages of shells of seep-dwelling bivalves to unravel fluid sources, formation conditions, and seepage dynamics. The two seeps (ROV1 and ROV2), referred to as 'Haima seeps' herein, are approximately 7 kilometers apart, and are typified by abundant carbonate rocks represented bycrusts and nodules. Aragonite and high-Mg calcite are the main carbonate minerals. Based on low δ13Ccarbonate values ranging from -43.0‰ to -27.5‰ (V-PDB) methane is apparently the predominant carbon source of seep carbonates. The corresponding δ18O values, varying from 2.5‰ to 5.8‰ (V-PDB), mostly are higher than calculated values representing precipitation in equilibrium with seawater (2.5‰ to 3.8‰), which probably reflects past destabilization of locally abundant gas hydrates. In addition, we found that carbonates with bivalve shells are generally aragonite-dominated, and bear no barium enrichment but uranium enrichments, reflecting shallow formation depths close to the seafloor. In contrast, carbonate crusts without bivalve shells and nodules contain more calcite, and are characterized by major molybdenum enrichment and different degrees of barium enrichment, agreeing with precipitation at greater depth under strictly anoxic conditions. AMS 14C ages suggest that a major episode of carbonate precipitation occurred between 6.1 ka and 5.1 ka BP at the Haima seeps, followed by a possibly subordinate episode from approximately 3.9 ka to 2.9 ka BP. The common occurrence of dead bivalves at both sites indicates that chemosynthesis-based communities flourished to a greater extent in the past, probably reflecting a decline of seepage activity in recent times. Overall, these results confirm that authigenic carbonates from

  1. Hydrothermal dolomitization of the Bekhme formation (Upper Cretaceous), Zagros Basin, Kurdistan Region of Iraq: Record of oil migration and degradation

    Science.gov (United States)

    Mansurbeg, Howri; Morad, Daniel; Othman, Rushdy; Morad, Sadoon; Ceriani, Andrea; Al-Aasm, Ihsan; Kolo, Kamal; Spirov, Pavel; Proust, Jean Noel; Preat, Alain; Koyi, Hemin

    2016-07-01

    The common presence of oil seepages in dolostones is widespread in Cretaceous carbonate successions of the Kurdistan Region of Iraq. This integrated field, petrographic, chemical, stable C, O and Sr isotopes, and fluid inclusion study aims to link dolomitization to the origin and geochemical evolution of fluids and oil migration in the Upper Cretaceous Bekhme carbonates. Flux of hot basinal (hydrothermal) brines, which is suggested to have occurred during the Zagros Orogeny, resulted in dolomitization and cementation of vugs and fractures by coarse-crystalline saddle dolomite, equant calcite and anhydrite. The saddle dolomite and host dolostones have similar stable isotopic composition and formed prior to oil migration from hot (81-115 °C) basinal NaCl-MgCl2-H2O brines with salinities of 18-22 wt.% NaCl eq. The equant calcite cement, which surrounds and hence postdates saddle dolomite, has precipitated during oil migration from cooler (60-110 °C) NaCl-CaCl2-H2O brines (14-18 wt.% NaCl eq). The yellowish fluorescence color of oil inclusions in the equant calcite indicates that the oil had API gravity of 15-25° composition, which is lighter than present-day oil in the reservoirs (API of 10-17°). This difference in oil composition is attributed to oil degradation by the flux of meteoric water, which is evidenced by the low δ13C values (- 8.5‰ to - 3.9‰ VPDB) as well as by nil salinity and low temperature in fluid inclusions of late columnar calcite cement. This study demonstrates that linking fluid flux history and related diagenesis to the tectonic evolution of the basin provides important clues to the timing of oil migration, degradation and reservoir evolution.

  2. A comparison of integrated river basin management strategies: A global perspective

    Science.gov (United States)

    Zhao, Chunhong; Wang, Pei; Zhang, Guanghong

    In order to achieve the integrated river basin management in the arid and rapid developing region, the Heihe River Basin (HRB) in Northwestern China, one of critical river basins were selected as a representative example, while the Murray-Darling Basin (MDB) in Australia and the Colorado River Basin (CRB) in the USA were selected for comparative analysis in this paper. Firstly, the comparable characters and hydrological contexts of these three watersheds were introduced in this paper. Then, based on comparative studies on the river basin challenges in terms of the drought, intensive irrigation, and rapid industrialization, the hydrological background of the MDB, the CRB and the HRB was presented. Subsequently, the river management strategies were compared in three aspects: water allocation, water organizations, and water act and scientific projects. Finally, we proposed recommendations for integrated river basin management for the HRB: (1) Water allocation strategies should be based on laws and markets on the whole basin; (2) Public participation should be stressed by the channels between governance organizations and local communities; (3) Scientific research should be integrated into river management to understand the interactions between the human and nature.

  3. Contrasting basin architecture and rifting style of the Vøring Basin, offshore mid-Norway and the Faroe-Shetland Basin, offshore United Kingdom

    Science.gov (United States)

    Schöpfer, Kateřina; Hinsch, Ralph

    2017-04-01

    The Vøring and the Faroe-Shetland basins are offshore deep sedimentary basins which are situated on the outer continental margin of the northeast Atlantic Ocean. Both basins are underlain by thinned continental crust whose structure is still debated. In particular the nature of the lower continental crust and the origin of high velocity bodies located at the base of the lower crust are a subject of discussion in recent literature. Regional interpretation of 2D and 3D seismic reflection data, combined with well data, suggest that both basins share several common features: (i) Pre-Cretaceous faults that are distributed across the entire basin width. (ii) Geometries of pre-Jurassic strata reflecting at least two extensional phases. (iii) Three common rift phases, Late Jurassic, Campanian-Maastrichtian and Palaeocene. (iv) Large pre-Cretaceous fault blocks that are buried by several kilometres of Cretaceous and Cenozoic strata. (iii). (v) Latest Cretaceous/Palaeocene inversion. (vi) Occurrence of partial mantle serpentinization during Early Cretaceous times, as proposed by other studies, seems improbable. The detailed analysis of the data, however, revealed significant differences between the two basins: (i) The Faroe-Shetland Basin was a fault-controlled basin during the Late Jurassic but also the Late Cretaceous extensional phase. In contrast, the Vøring Basin is dominated by the late Jurassic rifting and subsequent thermal subsidence. It exhibits only minor Late Cretaceous faults that are localised above intra-basinal and marginal highs. In addition, the Cretaceous strata in the Vøring Basin are folded. (ii) In the Vøring Basin, the locus of Late Cretaceous rifting shifted westwards, affecting mainly the western basin margin, whereas in the Faroe-Shetland Basin Late Cretaceous rifting was localised in the same area as the Late Jurassic phase, hence masking the original Jurassic geometries. (iii) Devono-Carboniferous and Aptian/Albian to Cenomanian rift phases

  4. H-Area Hazardous Waste Management Facility Corrective Action Report, Third and Fourth Quarter 1998, Volumes I and II

    International Nuclear Information System (INIS)

    Chase, J.

    1999-01-01

    The groundwater in the uppermost aquifer beneath the H-Area Hazardous Waste Management Facility (HWMF), also known as the H-Area Seepage Basins, at the Savannah Site (SRS) is monitored periodically for selected hazardous and radioactive constituents. This report presents the results of the required groundwater monitoring program

  5. Corrosion of aluminum alloys in a reactor disassembly basin

    International Nuclear Information System (INIS)

    Howell, J.P.; Zapp, P.E.; Nelson, D.Z.

    1992-01-01

    This document discusses storage of aluminum clad fuel and target tubes of the Mark 22 assembly takes place in the concrete-lined, light-water-filled, disassembly basins located within each reactor area at the Savannah River Site (SRS). A corrosion test program has been conducted in the K-Reactor disassembly basin to assess the storage performance of the assemblies and other aluminum clad components in the current basin environment. Aluminum clad alloys cut from the ends of actual fuel and target tubes were originally placed in the disassembly water basin in December 1991. After time intervals varying from 45--182 days, the components were removed from the basin, photographed, and evaluated metallographically for corrosion performance. Results indicated that pitting of the 8001 aluminum fuel clad alloy exceeded the 30-mil (0.076 cm) cladding thickness within the 45-day exposure period. Pitting of the 1100 aluminum target clad alloy exceeded the 30-mil (0.076 cm) clad thickness in 107--182 days exposure. The existing basin water chemistry is within limits established during early site operations. Impurities such as Cl - , NO 3 - and SO 4 - are controlled to the parts per million level and basin water conductivity is currently 170--190 μmho/cm. The test program has demonstrated that the basin water is aggressive to the aluminum components at these levels. Other storage basins at SRS and around the US have successfully stored aluminum components for greater than ten years without pitting corrosion. These basins have impurity levels controlled to the parts per billion level (1000X lower) and conductivity less than 1.0 μmho/cm

  6. Federal Facility Agreement progress report

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    The (SRS) Federal Facility Agreement (FFA) was made effective by the US. Environmental Protection Agency Region IV (EPA) on August 16, 1993. To meet the reporting requirements in Section XXV of the Agreement, the FFA Progress Report was developed. The FFA Progress Report is the first of a series of quarterly progress reports to be prepared by the SRS. As such this report describes the information and action taken to September 30, 1993 on the SRS units identified for investigation and remediation in the Agreement. This includes; rubble pits, runoff basins, retention basin, seepage basin, burning pits, H-Area Tank 16, and spill areas.

  7. Federal Facility Agreement progress report

    International Nuclear Information System (INIS)

    1993-10-01

    The (SRS) Federal Facility Agreement (FFA) was made effective by the US. Environmental Protection Agency Region IV (EPA) on August 16, 1993. To meet the reporting requirements in Section XXV of the Agreement, the FFA Progress Report was developed. The FFA Progress Report is the first of a series of quarterly progress reports to be prepared by the SRS. As such this report describes the information and action taken to September 30, 1993 on the SRS units identified for investigation and remediation in the Agreement. This includes; rubble pits, runoff basins, retention basin, seepage basin, burning pits, H-Area Tank 16, and spill areas

  8. The evolution of a Late Cretaceous-Cenozoic intraplate basin (Duaringa Basin), eastern Australia: evidence for the negative inversion of a pre-existing fold-thrust belt

    Science.gov (United States)

    Babaahmadi, Abbas; Sliwa, Renate; Esterle, Joan; Rosenbaum, Gideon

    2017-12-01

    The Duaringa Basin in eastern Australia is a Late Cretaceous?-early Cenozoic sedimentary basin that developed simultaneously with the opening of the Tasman and Coral Seas. The basin occurs on the top of an earlier (Permian-Triassic) fold-thrust belt, but the negative inversion of this fold-thrust belt, and its contribution to the development of the Duaringa Basin, are not well understood. Here, we present geophysical datasets, including recently surveyed 2D seismic reflection lines, aeromagnetic and Bouguer gravity data. These data provide new insights into the structural style in the Duaringa Basin, showing that the NNW-striking, NE-dipping, deep-seated Duaringa Fault is the main boundary fault that controlled sedimentation in the Duaringa Basin. The major activity of the Duaringa Fault is observed in the southern part of the basin, where it has undergone the highest amount of displacement, resulting in the deepest and oldest depocentre. The results reveal that the Duaringa Basin developed in response to the partial negative inversion of the pre-existing Permian-Triassic fold-thrust belt, which has similar orientation to the extensional faults. The Duaringa Fault is the negative inverted part of a single Triassic thrust, known as the Banana Thrust. Furthermore, small syn-depositional normal faults at the base of the basin likely developed due to the reactivation of pre-existing foliations, accommodation faults, and joints associated with Permian-Triassic folds. In contrast to equivalent offshore basins, the Duaringa Basin lacks a complex structural style and thick syn-rift sediments, possibly because of the weakening of extensional stresses away from the developing Tasman Sea.

  9. Fouling effects of tri-n-butylphosphate on reverse osmosis performance and techniques for performance recovery

    International Nuclear Information System (INIS)

    Poy, F.L.

    1987-01-01

    The F/H Effluent Treatment Facility (F/H ETF) must be on-line by November 1988 to treat the low level activity wastes presently being discharged to the F- and H- areas' seepage basins. The three main processes of the F/H ETF are filtration, reverse osmosis, and ion exchange. Any dissolved organics present in the F/H ETF's feed have the potential to affect operation of the reverse osmosis system. Earlier studies with F/H ETF feed simulant and 70 volume percent kerosene and 30 volume percent tri-n-butylphosphate (TBP) additions showed that the kerosene/TBP mixture results in partial fouling of reverse osmosis membranes. A more detailed analysis of the seepage basin feed has shown that TBP is the major dissolved organic compound. Since it is dissolved (soluble to about 400 ppM at 25 degree C), TBP will be present in the reverse osmosis feed unless removed by a means other than filtration. Thus the fouling effect of TBP (without kerosene) on reverse osmosis performance was investigated. 4 refs., 8 figs., 2 tabs

  10. Multi-scale evaluations of submarine groundwater discharge

    Directory of Open Access Journals (Sweden)

    M. Taniguchi

    2015-03-01

    Full Text Available Multi-scale evaluations of submarine groundwater discharge (SGD have been made in Saijo, Ehime Prefecture, Shikoku Island, Japan, by using seepage meters for point scale, 222Rn tracer for point and coastal scales, and a numerical groundwater model (SEAWAT for coastal and basin scales. Daily basis temporal changes in SGD are evaluated by continuous seepage meter and 222Rn mooring measurements, and depend on sea level changes. Spatial evaluations of SGD were also made by 222Rn along the coast in July 2010 and November 2011. The area with larger 222Rn concentration during both seasons agreed well with the area with larger SGD calculated by 3D groundwater numerical simulations.

  11. Estimating tectonic history through basin simulation-enhanced seismic inversion: Geoinformatics for sedimentary basins

    Science.gov (United States)

    Tandon, K.; Tuncay, K.; Hubbard, K.; Comer, J.; Ortoleva, P.

    2004-01-01

    A data assimilation approach is demonstrated whereby seismic inversion is both automated and enhanced using a comprehensive numerical sedimentary basin simulator to study the physics and chemistry of sedimentary basin processes in response to geothermal gradient in much greater detail than previously attempted. The approach not only reduces costs by integrating the basin analysis and seismic inversion activities to understand the sedimentary basin evolution with respect to geodynamic parameters-but the technique also has the potential for serving as a geoinfomatics platform for understanding various physical and chemical processes operating at different scales within a sedimentary basin. Tectonic history has a first-order effect on the physical and chemical processes that govern the evolution of sedimentary basins. We demonstrate how such tectonic parameters may be estimated by minimizing the difference between observed seismic reflection data and synthetic ones constructed from the output of a reaction, transport, mechanical (RTM) basin model. We demonstrate the method by reconstructing the geothermal gradient. As thermal history strongly affects the rate of RTM processes operating in a sedimentary basin, variations in geothermal gradient history alter the present-day fluid pressure, effective stress, porosity, fracture statistics and hydrocarbon distribution. All these properties, in turn, affect the mechanical wave velocity and sediment density profiles for a sedimentary basin. The present-day state of the sedimentary basin is imaged by reflection seismology data to a high degree of resolution, but it does not give any indication of the processes that contributed to the evolution of the basin or causes for heterogeneities within the basin that are being imaged. Using texture and fluid properties predicted by our Basin RTM simulator, we generate synthetic seismograms. Linear correlation using power spectra as an error measure and an efficient quadratic

  12. 3-D basin modelling of the Paris Basin: diagenetic and hydrogeologic implications

    International Nuclear Information System (INIS)

    Violette, S.; Goncalves, J.; Jost, A.; Marsily, G. de

    2004-01-01

    A 3-D basin model of the Paris basin is presented in order to simulate through geological times fluid, heat and solute fluxes. This study emphasizes: i) the contribution of basin models to the quantitative hydrodynamic understanding of behaviour of the basin over geological times; ii) the additional use of Atmospheric General Circulation model (AGCM) to provide palaeo-climatic boundaries for a coupled flow and mass transfer modelling, constrained by geochemical and isotopic tracers and; iii) the integration of different types of data (qualitative and quantitative) to better constrain the simulations. Firstly, in a genetic way, basin model is used to reproduce geological, physical and chemical processes occurring in the course of the 248 My evolution of the Paris basin that ought to explain the present-day hydraulic properties at the regional scale. As basin codes try to reproduce some of these phenomena, they should be able to give a plausible idea of the regional-scale permeability distribution of the multi-layered system, of the pre-industrial hydrodynamic conditions within the aquifers and of the diagenesis timing and type of hydrodynamic processes involved. Secondly, climate records archived in the Paris basin groundwater suggest that climate and morphological features have an impact on the hydrogeological processes, particularly during the last 5 My. An Atmospheric General Circulation model is used with a refined spatial resolution centred on the Paris basin to reproduce the climate for the present, the Last Glacial Maximum (21 ky) and the middle Pliocene (3 My). These climates will be prescribed, through forcing functions to the hydrological code with the main objective of understanding the way aquifers and aquitards react under different climate conditions, the period and the duration of these effects. Finally, the Paris basin has been studied for a number of years by different scientific communities, thus a large amount of data has been collected. By

  13. Hydro-mechanically coupled finite-element analysis of the stability of a fractured-rock slope using the equivalent continuum approach: a case study of planned reservoir banks in Blaubeuren, Germany

    Science.gov (United States)

    Song, Jie; Dong, Mei; Koltuk, Serdar; Hu, Hui; Zhang, Luqing; Azzam, Rafig

    2018-05-01

    Construction works associated with the building of reservoirs in mountain areas can damage the stability of adjacent valley slopes. Seepage processes caused by the filling and drawdown operations of reservoirs also affect the stability of the reservoir banks over time. The presented study investigates the stability of a fractured-rock slope subjected to seepage forces in the lower basin of a planned pumped-storage hydropower (PSH) plant in Blaubeuren, Germany. The investigation uses a hydro-mechanically coupled finite-element analyses. For this purpose, an equivalent continuum model is developed by using a representative elementary volume (REV) approach. To determine the minimum required REV size, a large number of discrete fracture networks are generated using Monte Carlo simulations. These analyses give a REV size of 28 × 28 m, which is sufficient to represent the equivalent hydraulic and mechanical properties of the investigated fractured-rock mass. The hydro-mechanically coupled analyses performed using this REV size show that the reservoir operations in the examined PSH plant have negligible effect on the adjacent valley slope.

  14. Hydro-mechanically coupled finite-element analysis of the stability of a fractured-rock slope using the equivalent continuum approach: a case study of planned reservoir banks in Blaubeuren, Germany

    Science.gov (United States)

    Song, Jie; Dong, Mei; Koltuk, Serdar; Hu, Hui; Zhang, Luqing; Azzam, Rafig

    2017-12-01

    Construction works associated with the building of reservoirs in mountain areas can damage the stability of adjacent valley slopes. Seepage processes caused by the filling and drawdown operations of reservoirs also affect the stability of the reservoir banks over time. The presented study investigates the stability of a fractured-rock slope subjected to seepage forces in the lower basin of a planned pumped-storage hydropower (PSH) plant in Blaubeuren, Germany. The investigation uses a hydro-mechanically coupled finite-element analyses. For this purpose, an equivalent continuum model is developed by using a representative elementary volume (REV) approach. To determine the minimum required REV size, a large number of discrete fracture networks are generated using Monte Carlo simulations. These analyses give a REV size of 28 × 28 m, which is sufficient to represent the equivalent hydraulic and mechanical properties of the investigated fractured-rock mass. The hydro-mechanically coupled analyses performed using this REV size show that the reservoir operations in the examined PSH plant have negligible effect on the adjacent valley slope.

  15. The Central European Permian Basins; Rheological and structural controls on basin history and on inter-basin connectivity

    NARCIS (Netherlands)

    Smit, Jeroen; van Wees, Jan-Diederik; Cloetingh, Sierd

    2014-01-01

    We analyse the relative importance of the major crustal-scale fault zones and crustal architecture in controlling basin formation, deformation and the structural connections between basins. The North and South Permian Basins of Central Europe are usually defined by the extend of Rotliegend

  16. Variations on seepage water geochemistry induced by natural and anthropogenic microclimatic changes: Implications for the speleothems growth conditions

    Science.gov (United States)

    Fernandez-Cortes, A.; Sanchez-Moral, S.; Canaveras, J. C.; Cuevas, J.; Cuezva, S.; Andreu, J. M.; Abella, R.

    2009-04-01

    During an annual cycle the effect of microclimatic changes (natural and anthropogenic origin) on the geochemical characteristics of seepage water and mineral precipitation rates was analyzed, for two karstic caves under opposing environmental stability and energy exchange with exterior. On the one hand Castañar cave (Caceres, Spain), an extremely controlled show cave with limited visitation showing a minimum exchange rate of energy with the outer atmosphere and, secondly, Canelobre cave (Alicante, Spain), a widely visited cave where the anthropogenic impact generates both high-speed and high-energy environmental changes. Microclimatic variations play a key role in CO2-dessgasing caused by the imbalance of pCO2 between the karstic water and the cave air, favoring the slow processes of mineral precipitation. Thus, a pCO2-range of seepage water have been detected for each cave (from 10-2.30/-2.35 to 10-2.47/-2.52 bar for Castañar cave, and from 10-2.8/-2.85 to 10-2.95/-3.0 bar for Canelobre cave) where the mineral oversaturation prevails, determining the type and rate of mineral precipitation in each cave. Finally, it analyzes how the changes on the oversaturation/ precipitation states are controlled by microclimatic variations, such as: 1) natural underground air renewal through the porous system of upper soil and the network of host-rock fissures (isolating membranes), or else through the cave entrance, 2) cumulative disruptions in the pCO2 levels of cave air due to the presence of visitors, and 3) forced ventilation of the subterranean atmosphere due to the uncontrolled opening of cave entrances. The obtained results reinforce the significance of the microclimatic fluctuations on short time scales in the dynamic and evolution of the subterranean karst system, in terms of rates of mineral precipitation and growth of speleothems. Likewise the interpretations are useful in order to ensure the constant climate required for the conservation of caves.

  17. The impact of fluid advection on gas hydrate stability: Investigations at sites of methane seepage offshore Costa Rica

    Science.gov (United States)

    Crutchley, G. J.; Klaeschen, D.; Planert, L.; Bialas, J.; Berndt, C.; Papenberg, C.; Hensen, C.; Hornbach, M. J.; Krastel, S.; Brueckmann, W.

    2014-09-01

    Fluid flow through marine sediments drives a wide range of processes, from gas hydrate formation and dissociation, to seafloor methane seepage including the development of chemosynthetic ecosystems, and ocean acidification. Here, we present new seismic data that reveal the 3D nature of focused fluid flow beneath two mound structures on the seafloor offshore Costa Rica. These mounds have formed as a result of ongoing seepage of methane-rich fluids. We show the spatial impact of advective heat flow on gas hydrate stability due to the channelled ascent of warm fluids towards the seafloor. The base of gas hydrate stability (BGHS) imaged in the seismic data constrains peak heat flow values to ∼60 mW m and ∼70 mW m beneath two separate seep sites known as Mound 11 and Mound 12, respectively. The initiation of pronounced fluid flow towards these structures was likely controlled by fault networks that acted as efficient pathways for warm fluids ascending from depth. Through the gas hydrate stability zone, fluid flow has been focused through vertical conduits that we suggest developed as migrating fluids generated their own secondary permeability by fracturing strata as they forced their way upwards towards the seafloor. We show that Mound 11 and Mound 12 (about 1 km apart on the seafloor) are sustained by independent fluid flow systems through the hydrate system, and that fluid flow rates across the BGHS are probably similar beneath both mounds. 2D seismic data suggest that these two flow systems might merge at approximately 1 km depth, i.e. much deeper than the BGHS. This study provides a new level of detail and understanding of how channelled, anomalously-high fluid flow towards the seafloor influences gas hydrate stability. Thus, gas hydrate systems have good potential for quantifying the upward flow of subduction system fluids to seafloor seep sites, since the fluids have to interact with and leave their mark on the hydrate system before reaching the seafloor.

  18. Thermal evolution of a hyperextended rift basin, Mauléon Basin, western Pyrenees

    Science.gov (United States)

    Hart, Nicole R.; Stockli, Daniel F.; Lavier, Luc L.; Hayman, Nicholas W.

    2017-06-01

    Onshore and offshore geological and geophysical observations and numerical modeling have greatly improved the conceptual understanding of magma-poor rifted margins. However, critical questions remain concerning the thermal evolution of the prerift to synrift phases of thinning ending with the formation of hyperextended crust and mantle exhumation. In the western Pyrenees, the Mauléon Basin preserves the structural and stratigraphic record of Cretaceous extension, exhumation, and sedimentation of the proximal-to-distal margin development. Pyrenean shortening uplifted basement and overlying sedimentary basins without pervasive shortening or reheating, making the Mauléon Basin an ideal locality to study the temporal and thermal evolution of magma-poor hyperextended rift systems through coupling bedrock and detrital zircon (U-Th)/He thermochronometric data from transects characterizing different structural rifting domains. These new data indicate that the basin was heated during early rifting to >180°C with geothermal gradients of 80-100°C/km. The proximal margin recorded rift-related exhumation/cooling at circa 98 Ma, whereas the distal margin remained >180°C until the onset of Paleocene Pyrenean shortening. Lithospheric-scale numerical modeling shows that high geothermal gradients, >80°C/km, and synrift sediments >180°C, can be reached early in rift evolution via heat advection by lithospheric depth-dependent thinning and blanketing caused by the lower thermal conductivity of synrift sediments. Mauléon Basin thermochronometric data and numerical modeling illustrate that reheating of basement and synrift strata might play an important role and should be considered in the future development of conceptual and numerical models for hyperextended magma-poor continental rifted margins.

  19. Performance prediction of a multi-basin solar still

    International Nuclear Information System (INIS)

    Mahdi, N.Al.

    1992-01-01

    A transient analysis for the prediction of the performance of a multi-basin solar still is presented. The energy-balance equations for the glass covers, the water masses and the absorber plate are manipulated to obtain a set of ordinary differential equations which are solved numerically. The analysis is applied to investigate the effect of the number of basins on the daily productivity of the still. Meteorological data corresponding to a June day in Bahrain have been used for the computation. The results indicate that the daily distillate output is increased by increasing the number of basins in the still. (author)

  20. A NEW METHOD FOR ENVIRONMENTAL FLOW ASSESSMENT BASED ON BASIN GEOLOGY. APPLICATION TO EBRO BASIN.

    Science.gov (United States)

    2018-02-01

    The determination of environmental flows is one of the commonest practical actions implemented on European rivers to promote their good ecological status. In Mediterranean rivers, groundwater inflows are a decisive factor in streamflow maintenance. This work examines the relationship between the lithological composition of the Ebro basin (Spain) and dry season flows in order to establish a model that can assist in the calculation of environmental flow rates.Due to the lack of information on the hydrogeological characteristics of the studied basin, the variable representing groundwater inflows has been estimated in a very simple way. The explanatory variable used in the proposed model is easy to calculate and is sufficiently powerful to take into account all the required characteristics.The model has a high coefficient of determination, indicating that it is accurate for the intended purpose. The advantage of this method compared to other methods is that it requires very little data and provides a simple estimate of environmental flow. It is also independent of the basin area and the river section order.The results of this research also contribute to knowledge of the variables that influence low flow periods and low flow rates on rivers in the Ebro basin.

  1. The effect of contaminated groundwater on tree growth: A tree-ring analysis

    International Nuclear Information System (INIS)

    LeBlanc, D.C.; Loehle, C.

    1990-10-01

    A study was conducted on the effect of contaminated groundwater seepage on tree growth downslope from F- and H-Area seepage basins of the Savannah River Site. Trees in wetlands along Four Mile Creek began to show localized stress and mortality in the late 1970s. Extreme winter temperatures and high rainfall were ruled out as potential causal factors of tree stress. Drought was shown to affect trees in both contaminated and uncontaminated zones, but trees in uncontaminated areas exhibit better recovery after drought than trees in contaminated areas. Pollution-mediated alteration of soil acidity and aluminum, sodium, and heavy metal concentrations likely acted to predispose trees to decline, with severe drought acting as the trigger for decline initiation and tree death. Thus, a moderate pollution loading, not sufficient to cause visible damage of itself, may create conditions in which sudden, severe decline could result from natural stresses. This mechanism of forest decline is common, and should be considered in evaluations of the impact of pollution on wetland forest systems. 28 refs., 4 figs., 6 tabs

  2. Active hydrocarbon (methane) seepage at the Alboran Sea mud volcanoes indicated by specific lipid biomarkers.

    Science.gov (United States)

    Lopez-Rodriguez, C.; Stadnitskaia, A.; De Lange, G. J.; Martínez-Ruiz, F.; Comas, M.; Sinninghe Damsté, J. S.

    2012-04-01

    Mud volcanoes (MVs) and pockmark fields are known to occur in the Alboran Basin (Westernmost Mediterranean). These MVs occur above a major sedimentary depocenter that includes up to 7 km thick early Miocene to Holocene sequences. MVs located on the top of diapiric structures that originated from undercompacted Miocene clays and olistostromes. Here we provide results from geochemical data-analyses of four gravity cores acquired in the Northern Mud Volcano Field (north of the 36°N): i.e. Perejil, Kalinin and Schneiderś Heart mud expulsion structures. Extruded materials include different types of mud breccias. Specific lipid biomarkers (n-alkanes, hopanes, irregular isoprenoid hydrocarbons and Dialkyl Glycerol Diethers (DGDs) were analysed by gas chromatography (GC) and gas chromatography mass spectrometry (GC-MS). Determination of Glycerol Dialkyl Glycerol Tetraethers (GDGTs) by high performance liquid chromatography-spectrometry (HPLC-MS), and analysis of biomarker δ13C values were performed in selected samples. Lipid biomarker analysis from the three MVs revealed similar n-alkane distributions in all mud breccia intervals, showing significant hydrocarbon-derived signals and the presence of thermally immature organic-matter admixture. This suggests that similar strata fed these MVs. The hemipelagic drapes reveal comparable n-alkane distributions, suggesting that significant upward diffusion of fluids occurs. Distributions of GDGTs are generally accepted as usefull biomarkers to locate the anaerobic oxidation of methane (AOM) in marine sediments. However, our GDGT profiles only reflect the marine thaumarchaeotal signature. There seems to be no archaea producing specific GDGTs involved in AOM in the recovered interval. Evidence of recent activity (i.e., methane gas-bubbling and chemosynthetic fauna at the Perejil MV) and the presence of specific lipid biomarker related with methanotropic archaea (Irregular Isoprenoids and DGDs), however, suggest the existence of

  3. Optimization techniques for the secondary development of old gas fields in the Sichuan Basin and their application

    Directory of Open Access Journals (Sweden)

    Chongshuang Xia

    2016-12-01

    Full Text Available After nearly 60 years of development, many old gas fields in the Sichuan Basin have come to middle–late development stages with low pressure and low yield, and some are even on the verge of abandonment, but there are plenty remaining gas resources still undeveloped. Analysis shows that gas fields which have the conditions for the secondary development are faced with many difficulties. For example, it is difficult to produce low permeable reserves and to unset the hydraulic seal which is formed by active formation water. In this paper, therefore, the technical route and selection conditions of old gas fields for the secondary development were comprehensively elaborated with its definition as the beginning. Firstly, geological model forward modeling and production performance inversion characteristic curve diagnosis are performed by using the pressure normalization curve and the identification and quantitative description method for multiple sets of storage–seepage body of complex karst fracture–cavity systems is put forward, after the multiple storage–seepage body mode of fracture–cavity systems is established. Combined with the new occurrence mode of gas and water in U-shape pipes, a new calculation technology for natural gas reserves of multiple fracture–cavity systems with strong water invasion is developed. Secondly, a numerical model of pore–cavity–fracture triple media is built, and simulation and result evaluation technology for the production pattern of “drainage by horizontal wells + gas production by vertical wells” in bottom-water fracture and cavity gas reservoirs with strong water invasion is developed. Thirdly, the geological model of gas reservoirs is reconstructed with the support of the integration technologies which are formed based on fine gas reservoir description. Low permeable reserves of gas reservoirs are evaluated based on each classification. The effective producing ratio is increased further by

  4. Fishes of the Taquari-Antas river basin (Patos Lagoon basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    FG. Becker

    Full Text Available The aquatic habitats of the Taquari-Antas river basin (in the Patos Lagoon basin, southern Brazil are under marked environmental transformation because of river damming for hydropower production. In order to provide an information baseline on the fish fauna of the Taquari-Antas basin, we provide a comprehensive survey of fish species based on primary and secondary data. We found 5,299 valid records of fish species in the basin, representing 119 species and 519 sampling sites. There are 13 non-native species, six of which are native to other Neotropical river basins. About 24% of the total native species are still lacking a taxonomic description at the species level. Three native long-distance migratory species were recorded (Leporinus obtusidens, Prochilodus lineatus, Salminus brasiliensis, as well as two potential mid-distance migrators (Parapimelodus nigribarbis and Pimelodus pintado. Although there is only one officially endangered species in the basin (S. brasiliensis, restricted range species (21.7% of total species should be considered in conservation efforts.

  5. The Controls of Pore-Throat Structure on Fluid Performance in Tight Clastic Rock Reservoir: A Case from the Upper Triassic of Chang 7 Member, Ordos Basin, China

    Directory of Open Access Journals (Sweden)

    Yunlong Zhang

    2018-01-01

    Full Text Available The characteristics of porosity and permeability in tight clastic rock reservoir have significant difference from those in conventional reservoir. The increased exploitation of tight gas and oil requests further understanding of fluid performance in the nanoscale pore-throat network of the tight reservoir. Typical tight sandstone and siltstone samples from Ordos Basin were investigated, and rate-controlled mercury injection capillary pressure (RMICP and nuclear magnetic resonance (NMR were employed in this paper, combined with helium porosity and air permeability data, to analyze the impact of pore-throat structure on the storage and seepage capacity of these tight oil reservoirs, revealing the control factors of economic petroleum production. The researches indicate that, in the tight clastic rock reservoir, largest throat is the key control on the permeability and potentially dominates the movable water saturation in the reservoir. The storage capacity of the reservoir consists of effective throat and pore space. Although it has a relatively steady and significant proportion that resulted from the throats, its variation is still dominated by the effective pores. A combination parameter (ε that was established to be as an integrated characteristic of pore-throat structure shows effectively prediction of physical capability for hydrocarbon resource of the tight clastic rock reservoir.

  6. Silage seepage and water protection. Production and recovery of silage seepage from animal feed and biomass for biogas plants. 7. ed.; Silagesickersaft und Gewaesserschutz. Anfall und Verwertung von Silagesickersaft aus Futtermitteln und Biomasse fuer Biogasanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Spiekers, Hubert [Bayerische Landesanstalt fuer Landwirtschaft (LfL), Freising-Weihenstephan (Germany); Attenberger, Erwin [Bayerisches Landesamt fuer Umwelt, Augsburg (Germany)

    2012-11-15

    The production of silage is now standard and an important basis for a successful milk and beef production. Silage is also needed in agricultural biogas plants as a substrate for energy production. This publication is intended to serve agriculture as a source of information and guidance document for the construction and operation of silos and the administration as an orientating work aid. The factors influencing the accumulation of silage seepage and the possibilities of prevention in silage and silage management are presented and evaluated from environmental and legal perspective. [German] Die Produktion von Silage ist heute Standard und eine wichtige Grundlage fuer eine erfolgreiche Milch- und Rindfleischerzeugung. Silage wird auch in landwirtschaftlichen Biogasanlagen als Substrat zur Energieerzeugung benoetigt. Die vorliegende Publikation soll der Landwirtschaft als Informationsquelle und Handlungsanleitung fuer den Bau und Betrieb von Siloanlagen und der Verwaltung als orientierende Arbeitshilfe dienen. Die Einflussgroessen auf den Anfall an Sickersaeften und die Moeglichkeiten der Vermeidung bei der Silierung und dem Silagemanagement werden dargestellt und aus umwelt- und rechtlicher Sicht bewertet.

  7. Slope effects on SWAT modeling in a mountainous basin

    OpenAIRE

    Yacoub López, Cristina; Pérez Foguet, Agustí

    2013-01-01

    The soil and water assessment tool (SWAT) is a distributed basin model that includes the option of defining spatial discretization in terms of terrain slope. Influence of terrain slope in runoff results from mountain basins is a determining factor in its simulation results; however, its use as a criterion for basin discretization and for the parameter calibration has not yet been analyzed. In this study, this influence is analyzed for calibrations using two different cases. Ten discretization...

  8. 4-D imaging of seepage in earthen embankments with time-lapse inversion of self-potential data constrained by acoustic emissions localization

    Science.gov (United States)

    Rittgers, J. B.; Revil, A.; Planes, T.; Mooney, M. A.; Koelewijn, A. R.

    2015-02-01

    New methods are required to combine the information contained in the passive electrical and seismic signals to detect, localize and monitor hydromechanical disturbances in porous media. We propose a field experiment showing how passive seismic and electrical data can be combined together to detect a preferential flow path associated with internal erosion in a Earth dam. Continuous passive seismic and electrical (self-potential) monitoring data were recorded during a 7-d full-scale levee (earthen embankment) failure test, conducted in Booneschans, Netherlands in 2012. Spatially coherent acoustic emissions events and the development of a self-potential anomaly, associated with induced concentrated seepage and internal erosion phenomena, were identified and imaged near the downstream toe of the embankment, in an area that subsequently developed a series of concentrated water flows and sand boils, and where liquefaction of the embankment toe eventually developed. We present a new 4-D grid-search algorithm for acoustic emissions localization in both time and space, and the application of the localization results to add spatially varying constraints to time-lapse 3-D modelling of self-potential data in the terms of source current localization. Seismic signal localization results are utilized to build a set of time-invariant yet spatially varying model weights used for the inversion of the self-potential data. Results from the combination of these two passive techniques show results that are more consistent in terms of focused ground water flow with respect to visual observation on the embankment. This approach to geophysical monitoring of earthen embankments provides an improved approach for early detection and imaging of the development of embankment defects associated with concentrated seepage and internal erosion phenomena. The same approach can be used to detect various types of hydromechanical disturbances at larger scales.

  9. K-Basins design guidelines

    International Nuclear Information System (INIS)

    Roe, N.R.; Mills, W.C.

    1995-06-01

    The purpose of the design guidelines is to enable SNF and K Basin personnel to complete fuel and sludge removal, and basin water mitigation by providing engineering guidance for equipment design for the fuel basin, facility modifications (upgrades), remote tools, and new processes. It is not intended to be a purchase order reference for vendors. The document identifies materials, methods, and components that work at K Basins; it also Provides design input and a technical review process to facilitate project interfaces with operations in K Basins. This document is intended to compliment other engineering documentation used at K Basins and throughout the Spent Nuclear Fuel Project. Significant provisions, which are incorporated, include portions of the following: General Design Criteria (DOE 1989), Standard Engineering Practices (WHC-CM-6-1), Engineering Practices Guidelines (WHC 1994b), Hanford Plant Standards (DOE-RL 1989), Safety Analysis Manual (WHC-CM-4-46), and Radiological Design Guide (WHC 1994f). Documents (requirements) essential to the engineering design projects at K Basins are referenced in the guidelines

  10. The Portland Basin: A (big) river runs through it

    Science.gov (United States)

    Evarts, Russell C.; O'Connor, Jim E.; Wells, Ray E.; Madin, Ian P.

    2009-01-01

    Metropolitan Portland, Oregon, USA, lies within a small Neogene to Holocene basin in the forearc of the Cascadia subduction system. Although the basin owes its existence and structural development to its convergent-margin tectonic setting, the stratigraphic architecture of basin-fill deposits chiefly reflects its physiographic position along the lower reaches of the continental-scale Columbia River system. As a result of this globally unique setting, the basin preserves a complex record of aggradation and incision in response to distant as well as local tectonic, volcanic, and climatic events. Voluminous flood basalts, continental and locally derived sediment and volcanic debris, and catastrophic flood deposits all accumulated in an area influenced by contemporaneous tectonic deformation and variations in regional and local base level.

  11. Hydrogeology, water quality, and potential for contamination of the Upper Floridan aquifer in the Silver Springs ground-water basin, central Marion County, Florida

    Science.gov (United States)

    Phelps, G.G.

    1994-01-01

    The Upper Floridan aquifer, composed of a thick sequence of very porous limestone and dolomite, is the principal source of water supply in the Silver Springs ground-water basin of central Marion County, Florida. The karstic nature of the local geology makes the aquifer susceptible to contaminants from the land surface. Contaminants can enter the aquifer by seepage through surficial deposits and through sinkholes and drainage wells. Potential contaminants include agricultural chemicals, landfill leachates and petroleum products from leaking storage tanks and accidental spills. More than 560 sites of potential contamination sources were identified in the basin in 1990. Detailed investigation of four sites were used to define hydrologic conditions at representative sites. Ground-water flow velocities determined from dye trace studies ranged from about 1 foot per hour under natural flow conditions to about 10 feet per hour under pumping conditions, which is considerably higher than velocities estimated using Darcy's equation for steady-state flow in a porous medium. Water entering the aquifer through drainage wells contained bacteria, elevated concentrations of nutrients, manganese and zinc, and in places, low concentrations of organic compounds. On the basis of results from the sampling of 34 wells in 1989 and 1990, and from the sampling of water entering the Upper Floridan aquifer through drainage wells, there has been no widespread degradation of water quality in the study area. In an area of karst, particularly one in which fracture flow is significant, evaluating the effects from contaminants is difficult and special care is required when interpolating hydrogeologic data from regional studies to a specific. (USGS)

  12. Did the Bering Sea Form as a Cenozoic Backarc Basin?

    Science.gov (United States)

    Stern, R. J.; Barth, G. A.; Scheirer, D. S.; Scholl, D. W.

    2012-12-01

    Understanding the origins of Bering Sea marginal basins (Aleutian, Bowers, and Komandorsky basins; AB, BB, KB) is key for reconstructing N. Pacific tectonic and magmatic evolution. New acquisitions and recompilations of MCS, OBS, and potential field data (Barth et al. poster. this session) for USGS Extended Continental Shelf project and selection of Aleutians as GeoPrisms Subduction Cycles and Deformation focus site stimulate reconsideration of BB, KB, and especially AB origins. AB has long been regarded as N. Pacific crust trapped when the Aleutian subduction began ~45-50 Ma. BB and KB probably formed together as Miocene backarc basins. Presence of Oligo-Miocene arc volcanics on Bowers and Shirshov ridges suggests that these are remnant arcs, orphaned by AB and KB opening. Seven lines of evidence suggest that AB formed as a Paleogene backarc basin: 1) AB heatflow suggests an age of about 44 Ma (Langseth et al 1980 JGR). 2) Formation of NNW-trending rift basins on Bering shelf (Navarin, Pribilof, and St. George basins) in Paleogene time indicate extension at this time. 3) The early Paleogene "red unconformity" of the Beringian margin could indicate uplift, erosion, and subsidence associated with AB opening. 4) ~N-S magnetic anomalies in AB contrasts with E-W Kula anomalies on N. Pacific, indicating that the two tracts of oceanic crust formed at different spreading ridges. 5) Thicker sediment in AB (2-4 km) vs. BB and KB (oceanic crust.ectonic scenario for formation of Aleutian Arc and Bering Sea basins. Green = present land; yellow = shelf; AB = Aleutian Basin; KB = Komandorsky Basin; BB = Bowers Basin; SR = Shirshov Ridge, BR = Bowers Ridge; Red = active volcanism and spreading ; Blue = extinct volcanism and spreading

  13. Developing a Science-based River Basin Management Plan for the Kharaa River Basin, Mongolia

    Science.gov (United States)

    Karthe, Daniel

    2013-04-01

    The Kharaa River Basin (KRB), which is located north of Mongolia's capital Ulaanbaatar and south of Lake Baikal, was chosen as a model region for the development and implementation of an integrated water resources management consisting of a monitoring concept, technical measures and a capacity development program (Karthe et al. 2012a). The basin of the Kharaa River covers an area of 14534 km² that is partly mountaineous and largely covered by taiga and steppe. At its outlet, the 362 km Kharaa River has a mean long-term annual discharge of 12.1 m³/s (MoMo Consortium 2009). A highly continental climate results in limited water resources, and rising water consumption coupled with the effects of climate and land use change may in the future exacerbate this water scarcity (Malsy et al. 2012; Karthe et al. 2013). Whereas the environment in the upper part of the catchment is in a relatively pristine state, the mid- and downstream sections of the river are characterized by nearby industry, mining activities and intensive agriculture (Menzel et al. 2011), resulting in declining water quality and ultimately a degradation of aquatic ecosystems (Hofmann et al. 2010; Hartwig et al. 2012). Moreover, it is a problem for the supply of major cities like Darkhan which largely rely on alluvial aquifers containing shallow-depth groundwater (Mun et al. 2008). Currently, there are alarming signs of water quality deterioration. With regard to water provision, a major problem is the poor state of distribution infrastructures which were often built in the 1960s and 70s (Scharaw & Westerhoff 2011). Rather little is currently known about the water quality supplied to end users; the latter is even more dubious in the city's informal ger districts (Karthe et al. 2012b). One important goal of the research and development project "Integrated Water Resources Management in Central Asia: Model Region Mongolia" lies in the implementation of a holistic concept for water resources monitoring and

  14. Quaternary base-level drops and trigger mechanisms in a closed basin: Geomorphic and sedimentological studies of the Gastre Basin, Argentina

    Science.gov (United States)

    Bilmes, Andrés; Veiga, Gonzalo D.; Ariztegui, Daniel; Castelltort, Sébastien; D'Elia, Leandro; Franzese, Juan R.

    2017-04-01

    Evaluating the role of tectonics and climate as possible triggering mechanisms of landscape reconfigurations is essential for paleoenvironmental and paleoclimatic reconstructions. In this study an exceptional receptive closed Quaternary system of Patagonia (the Gastre Basin) is described, and examined in order to analyze factors triggering base-level drops. Based on a geomorphological approach, which includes new tectonic geomorphology investigations combined with sedimentological and stratigraphic analysis, three large-scale geomorphological systems were identified, described and linked to two major lake-level highstands preserved in the basin. The results indicate magnitudes of base-level drops that are several orders of magnitude greater than present-day water-level fluctuations, suggesting a triggering mechanism not observed in recent times. Direct observations indicating the occurrence of Quaternary faults were not recorded in the region. In addition, morphometric analyses that included mountain front sinuosity, valley width-height ratio, and fan apex position dismiss tectonic fault activity in the Gastre Basin during the middle Pleistocene-Holocene. Therefore, we suggest here that upper Pleistocene climate changes may have been the main triggering mechanism of base-level falls in the Gastre Basin as it is observed in other closed basins of central Patagonia (i.e., Carri Laufquen Basin).

  15. Basins in ARC-continental collisions

    Science.gov (United States)

    Draut, Amy E.; Clift, Peter D.; Busby, Cathy; Azor, Antonio

    2012-01-01

    Arc-continent collisions occur commonly in the plate-tectonic cycle and result in rapidly formed and rapidly collapsing orogens, often spanning just 5-15 My. Growth of continental masses through arc-continent collision is widely thought to be a major process governing the structural and geochemical evolution of the continental crust over geologic time. Collisions of intra-oceanic arcs with passive continental margins (a situation in which the arc, on the upper plate, faces the continent) involve a substantially different geometry than collisions of intra-oceanic arcs with active continental margins (a situation requiring more than one convergence zone and in which the arc, on the lower plate, backs into the continent), with variable preservation potential for basins in each case. Substantial differences also occur between trench and forearc evolution in tectonically erosive versus tectonically accreting margins, both before and after collision. We examine the evolution of trenches, trench-slope basins, forearc basins, intra-arc basins, and backarc basins during arc-continent collision. The preservation potential of trench-slope basins is low; in collision they are rapidly uplifted and eroded, and at erosive margins they are progressively destroyed by subduction erosion. Post-collisional preservation of trench sediment and trench-slope basins is biased toward margins that were tectonically accreting for a substantial length of time before collision. Forearc basins in erosive margins are usually floored by strong lithosphere and may survive collision with a passive margin, sometimes continuing sedimentation throughout collision and orogeny. The low flexural rigidity of intra-arc basins makes them deep and, if preserved, potentially long records of arc and collisional tectonism. Backarc basins, in contrast, are typically subducted and their sediment either lost or preserved only as fragments in melange sequences. A substantial proportion of the sediment derived from

  16. Geochemical element mobility during the history of a Paleo-proterozoic clastic sedimentary basin, the Athabasca Basin (Saskatchewan, Canada)

    International Nuclear Information System (INIS)

    Kister, Philippe

    2003-01-01

    In order to understand the mechanisms of migration and deposition of ore elements, it is essential to determine the timing, source, and destination of the geochemical element mass transfers and/or transportation on a scale encompassing the great sedimentary basins. The purpose of this study is to trace and to date the element migrations that occurred during the history of a Paleo-proterozoic clastic sedimentary basin, the Athabasca Basin, which hosts the world's largest and richest uranium deposits. As this geological environment was proved to be efficient to preserve high grade ore deposits for over more than one billion years, it provides an opportunity to study some natural analogues of deep geological nuclear waste storage. Five research topics were studied: 3D modelling of the distribution of normative minerals and trace elements on a basin-wide scale; U-Pb and Rb-Sr systematics; average chemical age estimation; thermodynamic modelling of the major mineralogical assemblages; U-Pb geochronology of uranium oxides. Some elements have remained immobile (Zr) since their initial sedimentary deposition, or were transferred from one phase to another (Al, Th). Other elements have been transported during fluid flow events that occurred: (1) on a basin wide scale during diagenesis (REE, Y, Sr, Fe), (2) at the unconformity and in the vicinity of the fault zones that represent preferential fluid flow pathways between the basement and the sandstone cover (U, Ni, As, B, Mg, K, Fe, Sr, REE), (3) during the late fault reactivation events associated with the basin uplift (U, Pb, Ni, S, Sr, REE). The successive tectonic events related to the geodynamical context that lead to the formation of these high-grade U concentrations (1460 Ma, 1335 Ma and 1275 Ma in the McArthur River deposit), did not however systematically occur in the whole basin (1275 Ma only at Shea Creek). The exceptionally high grade and tonnages of some deposits seem to be related to a larger number of U

  17. Reduced gas seepages in serpentinized peridotite complexes: Evidences for multiple origins of the H2-CH4-N2 gas mixtures

    Science.gov (United States)

    Deville, E.; Vacquand, C.; Beaumont, V.; Francois, G.; Sissmann, O.; Pillot, D.; Arcilla, C. A.; Prinzhofer, A.

    2017-12-01

    A comparative study of reduced gas seepages associated to serpentinized ultrabasic rocks was conducted in the ophiolitic complexes of Oman, the Philippines, Turkey and New Caledonia. This study is based on analyzes of the gas chemical composition, noble gases contents, and stable isotopes of carbon, hydrogen and nitrogen. These gas seepages are mostly made of mixtures of three main components which are H2, CH4 and N2 in various proportions. The relative contents of the three main gas components show 4 distinct families of gas mixtures (H2-rich, N2-rich, N2-H2-CH4 and H2-CH4). These families are interpreted as reflecting different zones of gas generation within or below the ophiolitic complexes. In the H2-rich family associated noble gases display signatures close to the value of air. In addition to the atmospheric component, mantle and crustal contributions are present in the N2-rich, N2-H2-CH4 and H2-CH4 families. H2-bearing gases are either associated to ultra-basic (pH 10-12) spring waters or they seep directly in fracture systems from the ophiolitic rocks. In ophiolitic contexts, ultrabasic rocks provide an adequate environment with available Fe2+ and high pH conditions that favor H2 production. CH4 is produced either directly by reaction of dissolved CO2 with basic-ultrabasic rocks during the serpentinization process or in a second step by H2-CO2 interaction. H2 is present in the gas when no more carbon is available in the system to generate CH4 (conditions of strong carbon restriction). The N2-rich family is associated with relatively high contents of crustal 4He. In this family N2 is interpreted as issued mainly from sediments located below the ophiolitic units.

  18. Intra- and inter-basin mercury comparisons: Importance of basin scale and time-weighted methylmercury estimates

    International Nuclear Information System (INIS)

    Bradley, Paul M.; Journey, Celeste A.; Brigham, Mark E.; Burns, Douglas A.; Button, Daniel T.; Riva-Murray, Karen

    2013-01-01

    To assess inter-comparability of fluvial mercury (Hg) observations at substantially different scales, Hg concentrations, yields, and bivariate-relations were evaluated at nested-basin locations in the Edisto River, South Carolina and Hudson River, New York. Differences between scales were observed for filtered methylmercury (FMeHg) in the Edisto (attributed to wetland coverage differences) but not in the Hudson. Total mercury (THg) concentrations and bivariate-relationships did not vary substantially with scale in either basin. Combining results of this and a previously published multi-basin study, fish Hg correlated strongly with sampled water FMeHg concentration (ρ = 0.78; p = 0.003) and annual FMeHg basin yield (ρ = 0.66; p = 0.026). Improved correlation (ρ = 0.88; p < 0.0001) was achieved with time-weighted mean annual FMeHg concentrations estimated from basin-specific LOADEST models and daily streamflow. Results suggest reasonable scalability and inter-comparability for different basin sizes if wetland area or related MeHg-source-area metrics are considered. - Highlights: ► National scale mercury assessments integrate small scale study results. ► Basin scale differences and representativeness of fluvial mercury samples are concerns. ► Wetland area, not basin size, predicts inter-basin methylmercury variability. ► Time-weighted methylmercury estimates improve the prediction of mercury in basin fish. - Fluvial methylmercury concentration correlates with wetland area not basin scale and time-weighted estimates better predict basin top predator mercury than discrete sample estimates.

  19. Impact of land-use and climatic changes on hydrology of the Himalayan Basin: A case study of the Kosi Basin

    Science.gov (United States)

    Sharma, Keshav Prasad

    1997-10-01

    Land-use and climatic changes are of major concern in the Himalayan region because of their potential impacts on a predominantly agriculture-based economy and a regional hydrology dominated by strong seasonality. Such concerns are not limited to any particular basin but exist throughout the region including the downstream plain areas. As a representative basin of the Himalayas, we studied the Kosi basin (54,000 km2) located in the mountainous area of the central Himalayan region. We analyzed climatic and hydrologic information to assess the impacts of existing and potential future land-use and climatic changes over the basin. The assessment of anthropogenic inputs showed that the population grew at a compound growth rate of about one percent per annum over the basin during the last four decades. The comparison of land-use data based on the surveys made in the 1960s, and the surveys of 1978-79 did not reveal noticeable trends in land-use change. Analysis of meteorological and hydrological trends using parametric and nonparametric statistics for monthly data from 1947 to 1993 showed some increasing tendency for temperature and precipitation. Statistical tests of hydrological trends indicated an overall decrease of discharge along mainstem Kosi River and its major tributaries. The decreasing trends of streamflow were more significant during low-flow months. Statistical analysis of homogeneity showed that the climatological as well as the hydrological trends were more localized in nature lacking distinct basinwide significance. Statistical analysis of annual sediment time series, available for a single station on the Kosi River did not reveal a significant trend. We used water balance, statistical correlation, and distributed deterministic modeling approaches to analyze the hydrological sensitivity of the basin to possible land-use and climatic changes. The results indicated a stronger influence of basin characteristics compared to climatic characteristics on flow

  20. Delineating gas bearing reservoir by using spectral decomposition attribute: Case study of Steenkool formation, Bintuni Basin

    Science.gov (United States)

    Haris, A.; Pradana, G. S.; Riyanto, A.

    2017-07-01

    Tectonic setting of the Bird Head Papua Island becomes an important model for petroleum system in Eastern part of Indonesia. The current exploration has been started since the oil seepage finding in Bintuni and Salawati Basin. The biogenic gas in shallow layer turns out to become an interesting issue in the hydrocarbon exploration. The hydrocarbon accumulation appearance in a shallow layer with dry gas type, appeal biogenic gas for further research. This paper aims at delineating the sweet spot hydrocarbon potential in shallow layer by applying the spectral decomposition technique. The spectral decomposition is decomposing the seismic signal into an individual frequency, which has significant geological meaning. One of spectral decomposition methods is Continuous Wavelet Transform (CWT), which transforms the seismic signal into individual time and frequency simultaneously. This method is able to make easier time-frequency map analysis. When time resolution increases, the frequency resolution will be decreased, and vice versa. In this study, we perform low-frequency shadow zone analysis in which the amplitude anomaly at a low frequency of 15 Hz was observed and we then compare it to the amplitude at the mid (20 Hz) and the high-frequency (30 Hz). The appearance of the amplitude anomaly at a low frequency was disappeared at high frequency, this anomaly disappears. The spectral decomposition by using CWT algorithm has been successfully applied to delineate the sweet spot zone.

  1. Anatomy of a rift system: Triassic-Jurassic basins of eastern North America

    Energy Technology Data Exchange (ETDEWEB)

    Schlische, R.W. (Rutgers Univ., New Brunswick, NJ (United States)); Olsen, P.E. (Columbia Univ., Palisades, NY (United States))

    1991-03-01

    Basins containing the early Mesozoic Newark Supergroup formed during the incipient rifting of Pangaea. The basins are characterized by the following: (1) The border fault systems (BFS) represent reactivated older faults. (2) A regionally persistent northwest-southeast to west-northeast-east-southeast extension direction reactivated northeast- to north-striking structures as predominantly normal dip-slip faults. (3) The half-grabens are lozenge-shaped basins in which subsidence-fault slip was greatest at or near the center of the BFS and decreased to zero toward either end. (4) Transverse folds in the hanging walls immediately adjacent to the BFS formed as a result of higher-frequency variations in subsidence. (5) Subsidence also decreased in a direction perpendicular to the BFS. (6) Intrabasinal faults are overwhelmingly synthetic and predominantly post-depositional. (7) Younger strata progressively onlap prerift rocks of the hanging wall block; this indicates that the basins grew both in width and length as they filled. (8) In all basins initial sedimentation was fluvial, reflecting an oversupply of sediment with respect to basin capacity. (9) Sediments were derived largely from the hanging wall block, which sloped toward the basin, and from streams that entered the basin axially; a direct footwall source was minor, owing to footwall uplift. (10) In strike-slip-dominated basins, subsidence was considerably less than in dip-slip basins, and mosaics of strike- and dip-slip faults are common.

  2. Purex process

    International Nuclear Information System (INIS)

    Starks, J.B.

    1977-01-01

    The following aspects of the Purex Process are discussed: head end dissolution, first solvent extraction cycle, second plutonium solvent extraction cycle, second uranium solvent extraction cycle, solvent recovery systems, primary recovery column for high activity waste, low activity waste, laboratory waste evaporation, vessel vent system, airflow and filtration, acid recovery unit, fume recovery, and discharges to seepage basin

  3. SimBasin: serious gaming for integrated decision-making in the Magdalena-Cauca basin

    Science.gov (United States)

    Craven, Joanne; Angarita, Hector; Corzo, Gerald

    2016-04-01

    The Magdalena-Cauca macrobasin covers 24% of the land area of Colombia, and provides more than half of the country's economic potential. The basin is also home a large proportion of Colombia's biodiversity. These conflicting demands have led to problems in the basin, including a dramatic fall in fish populations, additional flooding (such as the severe nationwide floods caused by the La Niña phenomenon in 2011), and habitat loss. It is generally believed that the solution to these conflicts is to manage the basin in a more integrated way, and bridge the gaps between decision-makers in different sectors and scientists. To this end, inter-ministerial agreements are being formulated and a decision support system is being developed by The Nature Conservancy Colombia. To engage stakeholders in this process SimBasin, a "serious game", has been developed. It is intended to act as a catalyst for bringing stakeholders together, an illustration of the uncertainties, relationships and feedbacks in the basin, and an accessible introduction to modelling and decision support for non-experts. During the game, groups of participants are led through a 30 year future development of the basin, during which they take decisions about the development of the basin and see the impacts on four different sectors: agriculture, hydropower, flood risk, and environment. These impacts are displayed through seven indicators, which players should try to maintain above critical thresholds. To communicate the effects of uncertainty and climate variability, players see the actual value of the indicator and also a band of possible values, so they can see if their decisions have actually reduced risk or if they just "got lucky". The game works as a layer on top of a WEAP water resources model of the basin, adapted from a basin-wide model already created, so the fictional game basin is conceptually similar to the Magdalena-Cauca basin. The game is freely available online, and new applications are being

  4. A Case Study of the Densu Basin, Ghana

    African Journals Online (AJOL)

    komla

    and middle sections of the basin are covered with semi-deciduous forest with a lush growth of thick and tall trees. ... and scrub forest vegetation with only few isolated trees. There are ... which underlie the south-eastern part of the basin and the area south of Weija to the estuary. The rocks of ...... Association, Washington, D.C.

  5. Basin of Mexico: A history of watershed mismanagement

    Science.gov (United States)

    Luis A. Bojorquez Tapia; Exequiel Ezcurra; Marisa Mazari-Hiriart; Salomon Diaz; Paola Gomez; Georgina Alcantar; Daniela Megarejo

    2000-01-01

    Mexico City Metropolitan Zone (MCMZ) is located within the Basin of Mexico. Because of its large population and demand for natural resources, several authors have questioned the viability of the city, especially in terms of water resources. These are reviewed at the regional and the local scales. It is concluded that a multi-basin management approach is necessary to...

  6. PRELIMINARY DATA REPORT: HUMATE INJECTION AS AN ENHANCED ATTENUATION METHOD AT THE F-AREA SEEPAGE BASINS, SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Millings, M.

    2013-09-16

    A field test of a humate technology for uranium and I-129 remediation was conducted at the F-Area Field Research Site as part of the Attenuation-Based Remedies for the Subsurface Applied Field Research Initiative (ABRS AFRI) funded by the DOE Office of Soil and Groundwater Remediation. Previous studies have shown that humic acid sorbed to sediments strongly binds uranium at mildly acidic pH and potentially binds iodine-129 (I-129). Use of humate could be applicable for contaminant stabilization at a wide variety of DOE sites however pilot field-scale tests and optimization of this technology are required to move this technical approach from basic science to actual field deployment and regulatory acceptance. The groundwater plume at the F-Area Field Research Site contains a large number of contaminants, the most important from a risk perspective being strontium-90 (Sr-90), uranium isotopes, I-129, tritium, and nitrate. Groundwater remains acidic, with pH as low as 3.2 near the basins and increasing to the background pH of approximately 5at the plume fringes. The field test was conducted in monitoring well FOB 16D, which historically has shown low pH and elevated concentrations of Sr-90, uranium, I-129 and tritium. The field test included three months of baseline monitoring followed by injection of a potassium humate solution and approximately four and half months of post monitoring. Samples were collected and analyzed for numerous constituents but the focus was on attenuation of uranium, Sr-90, and I-129. This report provides background information, methodology, and preliminary field results for a humate field test. Results from the field monitoring show that most of the excess humate (i.e., humate that did not sorb to the sediments) has flushed through the surrounding formation. Furthermore, the data indicate that the test was successful in loading a band of sediment surrounding the injection point to a point where pH could return to near normal during the study

  7. Copper mobilization affected by weather conditions in a stormwater detention system receiving runoff waters from vineyard soils (Champagne, France)

    Energy Technology Data Exchange (ETDEWEB)

    Banas, D., E-mail: damien.banas@u-psud.f [Univ. Reims Champagne-Ardenne, Lab. Eco-Toxicologie, BP 1039, F-51687 Reims Cedex 2 (France); Univ. Nancy, UR-AFPA, INRA, 2 Av. Foret Haye, F-54505 Vandoeuvre-les-Nancy (France); Marin, B., E-mail: beatrice.marin@univ-reims.f [Univ. Reims Champagne-Ardenne, EA3795 GEGENA, 2 Esplanade Roland Garros, F-51100 Reims (France); Skraber, S., E-mail: skraber@lippmann.l [Centre de Recherche Public, Gabriel Lippmann, Department of Environment and Agro-biotechnologies (EVA), 41 rue du Brill, L-4422 Belvaux (Luxembourg); Chopin, E.I.B., E-mail: chopin@oakland.ed [Oakland University, Department of Chemistry, Rochester, MI 48309 (United States); Zanella, A., E-mail: augusto.zanella@unipd.i [Univ. Padova, Facolta di Agraria, Viale dell' Universita 16, I-35020 Legnaro (Italy)

    2010-02-15

    Copper, a priority substance on the EU-Water Framework Directive list, is widely used to protect grapevines against fungus diseases. Many vineyards being located on steep slopes, large amounts of Cu could be discharged in downstream systems by runoff water. The efficiency of stormwater detention basins to retain copper in a vineyard catchment was estimated. Suspended solids, dissolved (Cu{sub diss}) and total Cu (Cu{sub tot}) concentrations were monitored in runoff water, upstream, into and downstream from a detention pond. Mean Cu{sub tot} concentrations in entering water was 53.6 mug/L whereas it never exceeded 2.4 mug/L in seepage. Cu{sub tot} concentrations in basin water (>100 mug/L in 24% of the samples) exceeded LC{sub 50} values for several aquatic animals. Copper was principally sequestered by reduced compounds in the basin sediments (2/3 of Cu{sub tot}). Metal sequestration was reversible since sediment resuspension resulted in Cu remobilization. Wind velocity controlled resuspension, explained 70% of Cu{sub diss} variability and could help predicting Cu mobilization. - Copper in stormwater basin is efficiently retained but can be released during windy events or after dredging.

  8. Copper mobilization affected by weather conditions in a stormwater detention system receiving runoff waters from vineyard soils (Champagne, France)

    International Nuclear Information System (INIS)

    Banas, D.; Marin, B.; Skraber, S.; Chopin, E.I.B.; Zanella, A.

    2010-01-01

    Copper, a priority substance on the EU-Water Framework Directive list, is widely used to protect grapevines against fungus diseases. Many vineyards being located on steep slopes, large amounts of Cu could be discharged in downstream systems by runoff water. The efficiency of stormwater detention basins to retain copper in a vineyard catchment was estimated. Suspended solids, dissolved (Cu diss ) and total Cu (Cu tot ) concentrations were monitored in runoff water, upstream, into and downstream from a detention pond. Mean Cu tot concentrations in entering water was 53.6 μg/L whereas it never exceeded 2.4 μg/L in seepage. Cu tot concentrations in basin water (>100 μg/L in 24% of the samples) exceeded LC 50 values for several aquatic animals. Copper was principally sequestered by reduced compounds in the basin sediments (2/3 of Cu tot ). Metal sequestration was reversible since sediment resuspension resulted in Cu remobilization. Wind velocity controlled resuspension, explained 70% of Cu diss variability and could help predicting Cu mobilization. - Copper in stormwater basin is efficiently retained but can be released during windy events or after dredging.

  9. Drowning unconformity of lacustrine rift basins: A case study from the Dongying Sag in Bohai Bay Basin, China

    Science.gov (United States)

    Chen, R.; Fan, J.

    2015-12-01

    The concept of drowning unconformity of lacustrine rift basins was proposed in this paper. This paper utilized 3D seismic data, well-log and the principles methods associated with structural geology, sedimentology and geochemistry, to analyze the drowning unconformity and discuss the origins of drowning unconformity in Dongying Sag in Bohai Bay Basin.Researching on it is not only important for a better understanding of tectonic evolution, palaeogeography and sedimentation of hydrocarbon source rocks, but also a vital guiding significance for the exploration of beach-bar sandstone reservoirs and shale oil.1. The concept of drowning unconformity of lacustrine rift basins is defined. With the consequences of rapid tectonic subsidence in basin, the sharp rise of lake-level and the increased rate of accommodation(A) in basin exceeded the rate of sediment supply(S),namely A>>S, the basin suddenly transformed into deep-water settings from shallow-water settings with sudden change of sediment transport and sediment dispersal patterns. 2.The sequence surface between Sha4 and Sha3 Member of Shahejie Formation is the drowning unconformity(43.5Ma). There are the sedimentary association of the reefs in shallow lacustrine, beach-bar sandstones and glutenite fan bodies under the surface. By contrast, there are the sedimentary association of deep-lake oil shales and shales over the surface. The drowning unconformity in Dongying Sag is a tectonic revolution surface which is changed from extensional tectonics to transtensional tectonics and it is also the surface of discontinuity from shallow lacustrine to deep lacustrine. The responses to sudden changes appeared in the parameters of geophysics, geochemistry and paleontology. 3. With the penetration of India into Asia plate in NNE trending,the subduction zones of Pacific Plate retreated. It caused the rapid downwelling of asthenospheric mantle, followed by the extensive drowning unconformity.

  10. Superposition of tectonic structures leading elongated intramontane basin: the Alhabia basin (Internal Zones, Betic Cordillera)

    Science.gov (United States)

    Martínez-Martos, Manuel; Galindo-Zaldivar, Jesús; Martínez-Moreno, Francisco José; Calvo-Rayo, Raquel; Sanz de Galdeano, Carlos

    2017-10-01

    The relief of the Betic Cordillera was formed since the late Serravallian inducing the development of intramontane basins. The Alhabia basin, situated in the central part of the Internal Zones, is located at the intersection of the Alpujarran Corridor, the Tabernas basin, both trending E-W, and the NW-SE oriented Gádor-Almería basin. The geometry of the basin has been constrained by new gravity data. The basin is limited to the North by the Sierra de Filabres and Sierra Nevada antiforms that started to develop in Serravallian times under N-S shortening and to the south by Sierra Alhamilla and Sierra de Gádor antiforms. Plate convergence in the region rotated counter-clockwise in Tortonian times favouring the formation of E-W dextral faults. In this setting, NE-SW extension, orthogonal to the shortening direction, was accommodated by normal faults on the SW edge of Sierra Alhamilla. The Alhabia basin shows a cross-shaped depocentre in the zone of synform and fault intersection. This field example serves to constrain recent counter-clockwise stress rotation during the latest stages of Neogene-Quaternary basin evolution in the Betic Cordillera Internal Zones and underlines the importance of studying the basins' deep structure and its relation with the tectonic structures interactions.

  11. Morphometric analysis of Martian valley network basins using a circularity function

    Science.gov (United States)

    Luo, Wei; Howard, Alan D.

    2005-12-01

    This paper employs a circularity function to quantify the internal morphology of Martian watershed basins in Margaritifer Sinus region and to infer the primary erosional processes that led to their current geomorphologic characteristics and possible climatic conditions under which these processes operated. The circularity function describes the elongation of a watershed basin at different elevations. We have used the circularity functions of terrestrial basins that were interpreted as having been modified by (1) erosion related to primarily groundwater sapping and (2) erosion related to primarily rainfall and surface run-off, as well as the circularity functions of cratering basins on the Moon, in order to formulate discriminant functions that are able to separate the three types of landforms. The spatial pattern of the classification of Martian basins based on discriminant functions shows that basins that look morphologically similar to terrestrial fluvial basins are mostly clustered near the mainstream at low elevation, while those that look morphologically similar to terrestrial basins interpreted as groundwater sapping origin are located near the tributaries and at higher elevation. There are more of the latter than the former. This spatial distribution is inconsistent with a continuous Earth-like warm and wet climate for early Mars. Instead, it is more aligned with an overall early dry climate punctuated with episodic wet periods. Alternatively, the concentrated erosion in the mainstream could also be caused by a change of water source from rainfall to snowfall or erosion cut through a duricrust layer.

  12. A fate model for nitrogen dynamics in the Scheldt basin

    Science.gov (United States)

    Haest, Pieter Jan; van der Kwast, Johannes; Broekx, Steven; Seuntjens, Piet

    2010-05-01

    The European Union (EU) adopted the Water Framework Directive (WFD) in 2000 ensuring that all aquatic ecosystems meet ‘good ecological status' by 2015. However, the large population density in combination with agricultural and industrial activities in some European river basins pose challenges for river basin managers in meeting this status. The EU financed AQUAREHAB project (FP7) specifically examines the ecological and economic impact of innovative rehabilitation technologies for multi-pressured degraded waters. For this purpose, a numerical spatio-temporal model is developed to evaluate innovative technologies versus conventional measures at the river basin scale. The numerical model describes the nitrogen dynamics in the Scheldt river basin. Nitrogen is examined since nitrate is of specific concern in Belgium, the country comprising the largest area of the Scheldt basin. The Scheldt basin encompasses 20000 km2 and houses over 10 million people. The governing factors describing nitrogen fluxes at this large scale differ from the field scale with a larger uncertainty on input data. As such, the environmental modeling language PCRaster was selected since it was found to provide a balance between process descriptions and necessary input data. The resulting GIS-based model simulates the nitrogen dynamics in the Scheldt basin with a yearly time step and a spatial resolution of 1 square kilometer. A smaller time step is being evaluated depending on the description of the hydrology. The model discerns 4 compartments in the Scheldt basin: the soil, shallow groundwater, deep groundwater and the river network. Runoff and water flow occurs along the steepest slope in all model compartments. Diffuse emissions and direct inputs are calculated from administrative and statistical data. These emissions are geographically defined or are distributed over the domain according to land use and connectivity to the sewer system. The reactive mass transport is described using

  13. Eco-environmental impact of inter-basin water transfer projects: a review.

    Science.gov (United States)

    Zhuang, Wen

    2016-07-01

    The objective reality of uneven water resource distribution and imbalanced water demand of the human society makes it inevitable to transfer water. It has been an age-old method to adopt the inter-basin water transfers (IBTs) for alleviating and even resolving the urgent demand of the water-deficient areas. A number of countries have made attempts and have achieved enormous benefits. However, IBTs inevitably involve the redistribution of water resources in relevant basins and may cause changes of the ecological environment in different basins. Such changes are two-sided, namely, the positive impacts, including adding new basins for water-deficient areas, facilitating water cycle, improving meteorological conditions in the recipient basins, mitigating ecological water shortage, repairing the damaged ecological system, and preserving the endangered wild fauna and flora, as well as the negative impacts, including salinization and aridification of the donor basins, damage to the ecological environment of the donor basins and the both sides of the conveying channel system, increase of water consumption in the recipient basins, and spread of diseases, etc. Because IBTs have enormous ecological risk, it is necessary to comprehensively analyze the inter-basin water balance relationship, coordinate the possible conflicts and environmental quality problems between regions, and strengthen the argumentation of the ecological risk of water transfer and eco-compensation measures. In addition, there are some effective alternative measures for IBTs, such as attaching importance to water cycle, improving water use efficiency, developing sea water desalination, and rainwater harvesting technology, etc.

  14. Relating petroleum system and play development to basin evolution: West African South Atlantic basins

    NARCIS (Netherlands)

    Beglinger, S.E.; Doust, H.; Cloetingh, S.A.P.L.

    2012-01-01

    Sedimentary basins can be classified according to their structural genesis and evolutionary history and the latter can be linked to petroleumsystem and playdevelopment. We propose an approach in which we use the established concepts in a new way: breaking basins down into their natural basin cycle

  15. Ma'adim Vallis Estuarine Delta in Elysium Basin and Its Relevance as a Landing Site for Exobiology Exploration on Mars

    Science.gov (United States)

    Grin, E. A.; Cabrol, N. A.

    1998-01-01

    The debouche of Ma'adim Vallis in the Elysium Basin generated a transitional transported sediment structure, which planimetric shape is controlled by the enclosing topography of a deep reentrant gulf of the Basin into the highland. We defined it as an estuarine delta. The location and the importance of this estuarine delta is supported by the theoretical model of graded profile constructed for Ma'adim Vallis, and by two approaches: (i) the reconstruction of Ma'adim Vallis downstream course from Gusev to Elysium Basin, and (ii) the survey of the sediment deposit in the alleged estuary. The longitudinal graded profile of Ma'adim Vallis finds its base-level in the Elysium Basin, at a about 1000 m elevation, which is in agreement with the observed Basin shoreline. This model is supported by observational evidence of flow between the northern rim of Gusev crater, and the Elysium Basin shoreline. This downstream course of Ma'adim Vallis can be divided into three hydrogeologic regions. into three hydrogeologic regions. (a) The first region is a flooded plain (Zephiria Mensae), consisting in chaotic terrain formed by highland rocks, and disintegrated lava of the western flank of Apollinaris. Morphologic indicators of the flood process are: (1) the sediment deposit over the Gusev crater northern rim that reflects the overspilling of the crater-lake water through a 40-km wide gap provided by an ancient impact crater, (2) the tear-drop shaped feature on the northeastern flank of Apollinaris Patera, and (3) the chaotic terrain that suggest the emergence of ground water generated by the seepage of the crater lake through high-permeable broken rampart material. This underground water circulation sustained by the hydrostatic pressure of the crater-lake has likely generated a hydrothermal system in the volcanic environment of Apollinaris Patera. The stratigraphy of the flooded area is identified as Hesperian age, with occurrences of Noachian hilly individual features, and as

  16. Active intra-basin faulting in the Northern Basin of Lake Malawi from seismic reflection data

    Science.gov (United States)

    Shillington, D. J.; Chindandali, P. R. N.; Scholz, C. A.; Ebinger, C. J.; Onyango, E. A.; Peterson, K.; Gaherty, J. B.; Nyblade, A.; Accardo, N. J.; McCartney, T.; Oliva, S. J.; Kamihanda, G.; Ferdinand, R.; Salima, J.; Mruma, A. H.

    2016-12-01

    Many questions remain about the development and evolution of fault systems in weakly extended rifts, including the relative roles of border faults and intra-basin faults, and segmentation at various scales. The northern Lake Malawi (Nyasa) rift in the East African Rift System is an early stage rift exhibiting pronounced tectonic segmentation, which is defined by 100-km-long border faults. The basins also contain a series of intrabasinal faults and associated synrift sediments. The occurrence of the 2009 Karonga Earthquake Sequence on one of these intrabasinal faults indicates that some of them are active. Here we present new multichannel seismic reflection data from the Northern Basin of the Malawi Rift collected in 2015 as a part of the SEGMeNT (Study of Extension and maGmatism in Malawi aNd Tanzania) project. This rift basin is bound on its east side by the west-dipping Livingstone border fault. Over 650 km of seismic reflection profiles were acquired in the Northern Basin using a 500 to 1540 cu in air gun array and a 1200- to 1500-m seismic streamer. Dip lines image a series of north-south oriented west-dipping intra-basin faults and basement reflections up to 5 s twtt near the border fault. Cumulative offsets on intra-basin faults decrease to the west. The largest intra-basin fault has a vertical displacement of >2 s two-way travel time, indicating that it has accommodated significant total extension. Some of these intra-basin faults offset the lake bottom and the youngest sediments by up to 50 s twtt ( 37 m), demonstrating they are still active. The two largest intra-basin faults exhibit the largest offsets of young sediments and also correspond to the area of highest seismicity based on analysis of seismic data from the 89-station SEGMeNT onshore/offshore network (see Peterson et al, this session). Fault patterns in MCS profiles vary along the basin, suggesting a smaller scale of segmentation of faults within the basin; these variations in fault patterns

  17. Basin Hopping Graph

    DEFF Research Database (Denmark)

    Kucharik, Marcel; Hofacker, Ivo; Stadler, Peter

    2014-01-01

    of the folding free energy landscape, however, can provide the relevant information. Results We introduce the basin hopping graph (BHG) as a novel coarse-grained model of folding landscapes. Each vertex of the BHG is a local minimum, which represents the corresponding basin in the landscape. Its edges connect...

  18. The Removal Action Work Plan for CPP-603A Basin Facility

    International Nuclear Information System (INIS)

    B. T. Richards

    2006-01-01

    This revised Removal Action Work Plan describes the actions to be taken under the non-time-critical removal action recommended in the Action Memorandum for the Non-Time Critical Removal Action at the CPP-603A Basins, Idaho Nuclear Technology and Engineering Center, as evaluated in the Engineering Evaluation/Cost Analysis for the CPP-603A Basin Non-Time Critical Removal Action, Idaho Nuclear Technology and Engineering Center. The regulatory framework outlined in this Removal Action Work Plan has been modified from the description provided in the Engineering Evaluation/Cost Analysis (DOE/NE-ID-11140, Rev. 1, August 2004). The modification affects regulation of sludge removal, treatment, and disposal, but the end state and technical approaches have not changed. Revision of this document had been delayed until the basin sludge was successfully managed. This revision (Rev. 1) has been prepared to provide information that was not previously identified in Rev. 0 to describe the removal, treatment, and disposal of the basin water at the Idaho National Laboratory (INL) CERCLA Disposal Facility evaporation ponds and fill the basins with grout/controlled low strength material (CLSM) was developed. The Engineering Evaluation/Cost Analysis for the CPP-603A Basin Non-Time Critical Removal Action, Idaho Nuclear Technology and Engineering Center - conducted pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act - evaluated risks associated with deactivation of the basins and alternatives for addressing those risks. The decision to remove and dispose of the basin water debris not containing uranium grouted in place after the sludge has been removed and managed under the Hazardous Waste Management Act/Resource Conservation and Recovery Act has been documented in the Act Memorandum for the Non-Time Critical Removal Action at the CPP-603A Basins, Idaho Nuclear Technology and Engineering Center

  19. A regional approach to climate adaptation in the Nile Basin

    Directory of Open Access Journals (Sweden)

    M. B. Butts

    2016-10-01

    Full Text Available The Nile Basin is one of the most important shared basins in Africa. Managing and developing the water resources within the basin must not only address different water uses but also the trade-off between developments upstream and water use downstream, often between different countries. Furthermore, decision-makers in the region need to evaluate and implement climate adaptation measures. Previous work has shown that the Nile flows can be highly sensitive to climate change and that there is considerable uncertainty in climate projections in the region with no clear consensus as to the direction of change. Modelling current and future changes in river runoff must address a number of challenges; including the large size of the basin, the relative scarcity of data, and the corresponding dramatic variety of climatic conditions and diversity in hydrological characteristics. In this paper, we present a methodology, to support climate adaptation on a regional scale, for assessing climate change impacts and adaptation potential for floods, droughts and water scarcity within the basin.

  20. Geochemical evolution of groundwater salinity at basin scale: a case study from Datong basin, Northern China.

    Science.gov (United States)

    Wu, Ya; Wang, Yanxin

    2014-05-01

    A hydrogeochemical investigation using integrated methods of stable isotopes ((18)O, (2)H), (87)Sr/(86)Sr ratios, Cl/Br ratios, chloride-mass balance, mass balance and hydrogeochemical modeling was conducted to interpret the geochemical evolution of groundwater salinity in Datong basin, northern China. The δ(2)H, δ(18)O ratios in precipitation exhibited a local meteoric water line of δ(2)H = 6.4 δ(18)O -5 (R(2) = 0.94), while those in groundwater suggested their meteoric origin in a historically colder climatic regime with a speculated recharge rate of less than 20.5 mm overall per year, in addition to recharge from a component of deep residual ancient lake water enriched with Br. According to the Sr isotope binary mixing model, the mixing of recharges from the Shentou karst springs (24%), the western margins (11%) and the eastern margins (65%) accounts for the groundwater from the deep aquifers of the down-gradient parts in the central basin is a possible mixing mechanism. In Datong, hydrolysis of silicate minerals is the most important hydrogeochemical process responsible for groundwater chemistry, in addition to dissolution of carbonate and evaporites. In the recharge areas, silicate chemical weathering is typically at the bisiallitization stage, while that in the central basin is mostly at the monosiallitization stage with limited evidence of being in equilibrium with gibbsite. Na exchange with bound Ca, Mg prevails at basin scale, and intensifies with groundwater salinity, while Ca, Mg exchange with bound Na locally occurs in the east pluvial and alluvial plains. Although groundwater salinity increases with the progress of water-rock/sediment interactions along the flow path, as a result of carbonate solubility control and continuous evapotranspiration, Na-HCO3 and Na-Cl-SO4 types of water are usually characterized respectively in the deep and the shallow aquifers of an inland basin with a silicate terrain in an arid climatic regime.

  1. Frequency and sources of basin floor turbidites in alfonso basin, Gulf of California, Mexico: Products of slope failures

    Science.gov (United States)

    Gonzalez-Yajimovich, Oscar E.; Gorsline, Donn S.; Douglas, Robert G.

    2007-07-01

    Alfonso Basin is a small margin basin formed by extensional tectonics in the actively rifting, seismically active Gulf of California. The basin is centered at 24°40' N and 110° 38' W, and is a closed depression (maximum depth 420 m) with an effective sill depth of about 320 m (deepest sill), a width of 20 km and length of 25 km. Basin floor area below a depth of 350 m is about 260 km 2. The climate is arid to semiarid but was wetter during the early (ca. 10,000-7000 Calendar years Before Present [BP]) and middle Holocene (ca. 7000-4000 Cal. Years BP). Basin-wide turbidity currents reach the floor of Alfonso Basin at centennial to millennial intervals. The peninsular drainages tributary to the basin are small and have maximum flood discharges of the order of 10 4m 3. The basin-floor turbidites thicker than 1 cm have volumes of the order of 10 6m 3 to 10 8m 3 and require a much larger source. The largest turbidite seen in our cores is ca. 1 m thick in the central basin floor and was deposited 4900 Calendar Years Before Present (BP). Two smaller major events occurred about 1500 and 2800 Cal. Years BP. Seismicity over the past century of record shows a clustering of larger epicenters along faults forming the eastern Gulf side of Alfonso Basin. In that period there have been four earthquakes with magnitudes above 7.0 but all are distant from the basin. Frequency of such earthquakes in the basin vicinity is probably millennial. It is concluded that the basin-wide turbidites thicker than 1 cm must be generated by slope failures on the eastern side of the basin at roughly millennial intervals. The thin flood turbidites have a peninsular source at centennial frequencies.

  2. Potential for a significant deep basin geothermal system in Tintic Valley, Utah

    Science.gov (United States)

    Hardwick, C.; Kirby, S.

    2014-12-01

    The combination of regionally high heat flow, deep basins, and permeable reservoir rocks in the eastern Great Basin may yield substantial new geothermal resources. We explore a deep sedimentary basin geothermal prospect beneath Tintic Valley in central Utah using new 2D and 3D models coupled with existing estimates of heat flow, geothermometry, and shallow hydrologic data. Tintic Valley is a sediment-filled basin bounded to the east and west by bedrock mountain ranges where heat-flow values vary from 85 to over 240 mW/m2. Based on modeling of new and existing gravity data, a prominent 30 mGal low indicates basin fill thickness may exceed 2 km. The insulating effect of relatively low thermal conductivity basin fill in Tintic Valley, combined with typical Great Basin heat flow, predict temperatures greater than 150 °C at 3 km depth. The potential reservoir beneath the basin fill is comprised of Paleozoic carbonate and clastic rocks. The hydrology of the Tintic Valley is characterized by a shallow, cool groundwater system that recharges along the upper reaches of the basin and discharges along the valley axis and to a series of wells. The east mountain block is warm and dry, with groundwater levels just above the basin floor and temperatures >50 °C at depth. The west mountain block contains a shallow, cool meteoric groundwater system. Fluid temperatures over 50 °C are sufficient for direct-use applications, such as greenhouses and aquaculture, while temperatures exceeding 140°C are suitable for binary geothermal power plants. The geologic setting and regionally high heat flow in Tintic Valley suggest a geothermal resource capable of supporting direct-use geothermal applications and binary power production could be present.

  3. Three-dimensional modeling of pull-apart basins: implications for the tectonics of the Dead Sea Basin

    Science.gov (United States)

    Katzman, Rafael; ten Brink, Uri S.; Lin, Jian

    1995-01-01

    We model the three-dimensional (3-D) crustal deformation in a deep pull-apart basin as a result of relative plate motion along a transform system and compare the results to the tectonics of the Dead Sea Basin. The brittle upper crust is modeled by a boundary element technique as an elastic block, broken by two en echelon semi-infinite vertical faults. The deformation is caused by a horizontal displacement that is imposed everywhere at the bottom of the block except in a stress-free “shear zone” in the vicinity of the fault zone. The bottom displacement represents the regional relative plate motion. Results show that the basin deformation depends critically on the width of the shear zone and on the amount of overlap between basin-bounding faults. As the width of the shear zone increases, the depth of the basin decreases, the rotation around a vertical axis near the fault tips decreases, and the basin shape (the distribution of subsidence normalized by the maximum subsidence) becomes broader. In contrast, two-dimensional plane stress modeling predicts a basin shape that is independent of the width of the shear zone. Our models also predict full-graben profiles within the overlapped region between bounding faults and half-graben shapes elsewhere. Increasing overlap also decreases uplift near the fault tips and rotation of blocks within the basin. We suggest that the observed structure of the Dead Sea Basin can be described by a 3-D model having a large overlap (more than 30 km) that probably increased as the basin evolved as a result of a stable shear motion that was distributed laterally over 20 to 40 km.

  4. River basin administration

    Science.gov (United States)

    Management of international rivers and their basins is the focus of the Centre for Comparative Studies on (International) River Basin Administration, recently established at Delft University of Technology in the Netherlands. Water pollution, sludge, and conflicting interests in the use of water in upstream and downstream parts of a river basin will be addressed by studying groundwater and consumption of water in the whole catchment area of a river.Important aspects of river management are administrative and policy aspects. The Centre will focus on policy, law, planning, and organization, including transboundary cooperation, posing standards, integrated environmental planning on regional scale and environmental impact assessments.

  5. Climate and tectonic evolution of the Descanso-Yauri basin in the northernmost Altiplano: Archetype example of a 'lithospheric drip' basin

    Science.gov (United States)

    Kar, N.; Garzione, C. N.

    2015-12-01

    We present a new multiproxy Miocene-Pliocene paleoelevation record of the northernmost Altiplano plateau reconstructed from pollen, clumped isotope (TΔ47) and δ18Oc of sedimentary carbonates and leaf wax n-alkane δD signatures. The ~18Ma to ~9Ma deposits of our study area, Descanso-Yauri basin in southern Peru show 11 to 16ºC warmer than modern mean annual air temperature, low elevation vegetation pollen assemblage (dominated by Podocarpus), and an average precipitation δ18Omw (VSMOW) value of -8.3±2.0‰ (2σ). The ~5 to 4 Ma deposits in the Descanso-Yauri basin are characterized by herb and shrub vegetation and an average δ18O mw (VSMOW) value of -14.6±3.0‰ (2σ), indicative of an elevation and/or climate similar to modern conditions. Based on the multiproxy paleoclimate record, we interpret that there was a 2±1 km surface uplift between 9 and 5 Ma in the northernmost Altiplano plateau. Deformation history analysis through map scale structural investigation combined with provenance analysis from conglomerate clast composition and paleocurrents show that the thrusts bounding the NE side of the Descanso-Yauri basin were active until ˜9Ma. Deformation waned afterwards, and switched to an extensional deformation regime, coincident with decrease in subsidence rate from ˜0.2mm/year to ˜0.03mm/year. Depositional history reconstructed by facies analysis and stratigraphic correlation reveal that deposition in the basin began with transverse braided river systems that formed along the thrust front and gave way to a larger fluvial-lacustrine system until ˜4 Ma. The basin deposits show an overall fining upward trend from coarse clastic dominated, in the lower most parts of the basin fill to fluvial overbank and lacustrine mudstone and diatomite deposits in the middle-upper parts. The thickest deposits formed in the central part of the basin. Based on these depositional and deformational patterns, we infer that the Descanso-Yauri basin formed in response to a

  6. Assessing groundwater recharge in an Andean closed basin using isotopic characterization and a rainfall-runoff model: Salar del Huasco basin, Chile

    Science.gov (United States)

    Uribe, Javier; Muñoz, José F.; Gironás, Jorge; Oyarzún, Ricardo; Aguirre, Evelyn; Aravena, Ramón

    2015-11-01

    Closed basins are catchments whose drainage networks converge to lakes, salt flats or alluvial plains. Salt flats in the closed basins in arid northern Chile are extremely important ecological niches. The Salar del Huasco, one of these salt flats located in the high plateau (Altiplano), is a Ramsar site located in a national park and is composed of a wetland ecosystem rich in biodiversity. The proper management of the groundwater, which is essential for the wetland function, requires accurate estimates of recharge in the Salar del Huasco basin. This study quantifies the spatio-temporal distribution of the recharge, through combined use of isotopic characterization of the different components of the water cycle and a rainfall-runoff model. The use of both methodologies aids the understanding of hydrological behavior of the basin and enabled estimation of a long-term average recharge of 22 mm/yr (i.e., 15 % of the annual rainfall). Recharge has a high spatial variability, controlled by the geological and hydrometeorological characteristics of the basin, and a high interannual variability, with values ranging from 18 to 26 mm/yr. The isotopic approach allowed not only the definition of the conceptual model used in the hydrological model, but also eliminated the possibility of a hydrogeological connection between the aquifer of the Salar del Huasco basin and the aquifer that feeds the springs of the nearby town of Pica. This potential connection has been an issue of great interest to agriculture and tourism activities in the region.

  7. Hydrochemical simulation of a mountain basin under hydrological variability

    Science.gov (United States)

    Montserrat, S.; Trewhela, T. A.; Navarro, L.; Navarrete, A.; Lagos Zuniga, M. A.; Garcia, A.; Caraballo, M.; Niño, Y.; McPhee, J. P.

    2016-12-01

    Water quality and the comprehension of hydrochemical phenomena in natural basins should be of complete relevance under hydrological uncertainties. The importance of identifying the main variables that are controlling a natural system and finding a way to predict their behavior under variable scenarios is mandatory to preserve these natural basins. This work presents an interdisciplinary model for the Yerba Loca watershed, a natural reserve basin in the Chilean central Andes. Based on different data sets, provided by public and private campaigns, a natural hydrochemical regime was identified. Yerba Loca is a natural reserve, characterized by the presence of several glaciers and wide sediment deposits crossed by a small low-slope creek in the upper part of the basin that leads to a high-slope narrow channel with less sediment depositions. Most relevant is the geological context around the glaciers, considering that most of them cover hydrothermal zones rich in both sulfides and sulfates, a situation commonly found in the Andes due to volcanic activity. Low pH (around 3), calcium-sulfate water with high concentrations of Iron, Copper and Zinc are found in the upper part of the basin in summer. These values can be attributed to the glaciers melting down and draining of the mentioned country rocks, which provide most of the creek flow in the upper basin. The latter clearly contrasts with the creek outlet, located 18 km downstream, showing near to neutral pH values and lower concentrations of the elements already mentioned. The scope of the present research is to account for the sources of the different hydrological inlets (e.g., rainfall, snow and/or glacier melting) that, depending on their location, may interact with a variety of reactive minerals and generate acid rock drainage (ARD). The inlet water is modeled along the creek using the softwares HEC-RAS and PHREEQC coupled, in order to characterize the water quality and to detect preferred sedimentation sections

  8. Mapping Monthly Water Scarcity in Global Transboundary Basins at Country-Basin Mesh Based Spatial Resolution.

    Science.gov (United States)

    Degefu, Dagmawi Mulugeta; Weijun, He; Zaiyi, Liao; Liang, Yuan; Zhengwei, Huang; Min, An

    2018-02-01

    Currently fresh water scarcity is an issue with huge socio-economic and environmental impacts. Transboundary river and lake basins are among the sources of fresh water facing this challenge. Previous studies measured blue water scarcity at different spatial and temporal resolutions. But there is no global water availability and footprint assessment done at country-basin mesh based spatial and monthly temporal resolutions. In this study we assessed water scarcity at these spatial and temporal resolutions. Our results showed that around 1.6 billion people living within the 328 country-basin units out of the 560 we assessed in this study endures severe water scarcity at least for a month within the year. In addition, 175 country-basin units goes through severe water scarcity for 3-12 months in the year. These sub-basins include nearly a billion people. Generally, the results of this study provide insights regarding the number of people and country-basin units experiencing low, moderate, significant and severe water scarcity at a monthly temporal resolution. These insights might help these basins' sharing countries to design and implement sustainable water management and sharing schemes.

  9. Temporal and basin-specific population trends of quagga mussels on soft sediment of a multi-basin reservoir

    Science.gov (United States)

    Caldwell, Timothy J; Rosen, Michael R.; Chandra, Sudeep; Acharya, Kumud; Caires, Andrea M; Davis, Clinton J.; Thaw, Melissa; Webster, Daniel M.

    2015-01-01

    Invasive quagga (Dreissena bugnesis) and zebra (Dreissena ploymorpha) mussels have rapidly spread throughout North America. Understanding the relationships between environmental variables and quagga mussels during the early stages of invasion will help management strategies and allow researchers to predict patterns of future invasions. Quagga mussels were detected in Lake Mead, NV/AZ in 2007, we monitored early invasion dynamics in 3 basins (Boulder Basin, Las Vegas Bay, Overton Arm) bi-annually from 2008-2011. Mean quagga density increased over time during the first year of monitoring and stabilized for the subsequent two years at the whole-lake scale (8 to 132 individuals·m-2, geometric mean), in Boulder Basin (73 to 875 individuals·m-2), and in Overton Arm(2 to 126 individuals·m-2). In Las Vegas Bay, quagga mussel density was low (9 to 44 individuals·m-2), which was correlated with high sediment metal concentrations and warmer (> 30°C) water temperatures associated with that basin. Carbon content in the sediment increased with depth in Lake Mead and during some sampling periods quagga density was also positively correlated with depth, but more research is required to determine the significance of this interaction. Laboratory growth experiments suggested that food quantity may limit quagga growth in Boulder Basin, indicating an opportunity for population expansion in this basin if primary productivity were to increase, but was not the case in Overton Arm. Overall quagga mussel density in Lake Mead is highly variable and patchy, suggesting that temperature, sediment size, and sediment metal concentrations, and sediment carbon content all contribute to mussel distribution patterns. Quagga mussel density in the soft sediment of Lake Mead expanded during initial colonization, and began to stabilize approximately 3 years after the initial invasion.

  10. Hydrochemical evolution and groundwater flow processes in the Galilee and Eromanga basins, Great Artesian Basin, Australia: a multivariate statistical approach.

    Science.gov (United States)

    Moya, Claudio E; Raiber, Matthias; Taulis, Mauricio; Cox, Malcolm E

    2015-03-01

    The Galilee and Eromanga basins are sub-basins of the Great Artesian Basin (GAB). In this study, a multivariate statistical approach (hierarchical cluster analysis, principal component analysis and factor analysis) is carried out to identify hydrochemical patterns and assess the processes that control hydrochemical evolution within key aquifers of the GAB in these basins. The results of the hydrochemical assessment are integrated into a 3D geological model (previously developed) to support the analysis of spatial patterns of hydrochemistry, and to identify the hydrochemical and hydrological processes that control hydrochemical variability. In this area of the GAB, the hydrochemical evolution of groundwater is dominated by evapotranspiration near the recharge area resulting in a dominance of the Na-Cl water types. This is shown conceptually using two selected cross-sections which represent discrete groundwater flow paths from the recharge areas to the deeper parts of the basins. With increasing distance from the recharge area, a shift towards a dominance of carbonate (e.g. Na-HCO3 water type) has been observed. The assessment of hydrochemical changes along groundwater flow paths highlights how aquifers are separated in some areas, and how mixing between groundwater from different aquifers occurs elsewhere controlled by geological structures, including between GAB aquifers and coal bearing strata of the Galilee Basin. The results of this study suggest that distinct hydrochemical differences can be observed within the previously defined Early Cretaceous-Jurassic aquifer sequence of the GAB. A revision of the two previously recognised hydrochemical sequences is being proposed, resulting in three hydrochemical sequences based on systematic differences in hydrochemistry, salinity and dominant hydrochemical processes. The integrated approach presented in this study which combines different complementary multivariate statistical techniques with a detailed assessment of the

  11. K Basin safety analysis

    International Nuclear Information System (INIS)

    Porten, D.R.; Crowe, R.D.

    1994-01-01

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall

  12. Quantification and Postglacial evolution of an inner alpine sedimentary basin (Gradenmoos Basin, Hohe Tauern)

    International Nuclear Information System (INIS)

    Götz, J.

    2012-01-01

    The overall objective of this thesis is the quantification of sediment storage and the reconstruction of postglacial landscape evolution within the glacially overdeepened Gradenmoos Basin (subcatchment size: 4.1 km 2 ; basin floor elevation: 1920 m) in the central Gradenbach catchment (Schober Range, Hohe Tauern, Austrian Alps). Following the approach of denudation-accumulation-systems, most reliable results are obtained (1) if sediment output of a system can be neglected for an established period of time, (2) if sediment storage can be assessed with a high level of accuracy, (3) if the onset of sedimentation and amounts of initially stored sediments are known, and (4) if sediment contributing areas can be clearly delimited. Due to spatial scale and topographic characteristics, all mentioned aspects are fulfilled to a high degree within the studied basin. Applied methods include surface, subsurface and temporal investigations. Digital elevation data is derived from terrestrial laserscanning and geomorphologic mapping. The quantification of sediment storage is based on core drillings, geophysical methods (DC resistivity, refraction seismic, and ground penetrating radar), as well as GIS and 3D modelling. Radiocarbon dating and palynological analyses are additionally used to reconstruct the postglacial infilling progress of the basin. The study reveals that a continuous postglacial stratigraphic record is archived in the basin. As proposed by Lieb (1987) timing of basin deglaciation could be verified to late-Egesen times by means of radiocarbon ages (oldest sample just above basal till: 10.4 ka cal. BP) and first palynologic results. Lateglacial oscillations seem to have effectively scoured the basin, leaving only a shallow layer of basal till. The analysis of postglacial sedimentation in the basin is further improved by the existence of a former lake in the basin lasting for up to 7500 years until approx. 3.7 ka cal. BP. Both, the stratigraphic (fine, partly

  13. A basin on an unstable ground: Correlation of the Middle Archaean Moodies Basin, Barberton Greenstone Belt, South Africa

    Science.gov (United States)

    Ohnemueller, Frank; Heubeck, Christoph; Kirstein, Jens; Gamper, Antonia

    2010-05-01

    The 3.22 Ga-old Moodies Group, representing the uppermost part of the Barberton Supergroup of the Barberton Greenstone Belt (BGB), is the oldest well-exposed, relatively unmetamorphosed, quartz-rich sedimentary unit on Earth. Moodies facies (north of the Inyoka Fault) were thought to be largely of alluvial, fluvial, deltaic or shallow-marine origin (Anhaeusser, 1976; Eriksson, 1980; Heubeck and Lowe, 1994) and in its upper part syndeformational. However, units can only locally be correlated, and the understanding of the interplay between Moodies sedimentation and deformation is thus limited. We mapped and measured Moodies units in the northern BGB. They partly consist of extensive turbiditic deepwater deposits, including graded bedding, flame structures, and slumped beds, interbedded with jaspilites. These contrast with shallow-water environments, south-facing progressive unconformities and overlying alluvial-fan conglomerates along the northern margin of the Saddleback Syncline further south. The palaeogeographic setting in which late BGB deformation was initiated therefore appears complex and cannot be readily explained by a simple southward-directed shortening event. In order to constrain Moodies basin setting before and during late-Moodies basin collapse, we correlated ~15 measured sections in the northern and central BGB. Most units below the Moodies Lava (MdL, ca. 3230.6+-6 Ma) can be correlated throughout although facies variations are apparent. Above the Moodies Lava, coarse-grained units can only be correlated through the Eureka Syncline and the Moodies Hills Block but not with the Saddleback Syncline. Fine-grained and jaspilitic units can be correlated throughout the northern BGB. Moodies below-wavebase deposition occurred largely north of the Saddleback Fault. The observations are consistent with a pronounced basin compartmentalization event following the eruption of the MdL which appeared to have blanketed most of the Moodies basin(s) in middle Moodies

  14. A review of the petroleum geochemistry of the Precaspian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Pairazian, V.V. [All-Russian Geological Oil Research and Prospecting Inst. (VNIGNI), Moscow (Russian Federation); ENI-AGIP, San Donato Milanese (Italy)

    1999-11-01

    On the territory of the former Soviet Union more than 30- oil and gas-bearing basins have been defined. Among them the Precaspian basin is one of the most prolific in terms of oil and gas exploration and production. The basin is situated in the southeastern part of the East European Platform and covers an areas of about 500 000 km{sup 2}. There are a number of source rocks of different ages, among which the principal ones are Lower Permian, Middle Carboniferous and Middle Devonian marine shales and carbonates. The post-salt Mesozoic sources are of less significance. Geological and geochemical data interpretation allows the main oil/gas accumulation zones and new exploration prospects to be defined. Two main petroleum systems are recognised in the Palaeozoic sequence of the basin, containing 90% of the recoverable hydrocarbon resources: Lower Permian-Middle Carboniferous and Lower Carboniferous-Upper Devonian. The new exploration targets are deep Middle Devonian clastic reservoirs on the passive continental margins and Middle Carboniferous (Bashkirian) carbonates in the Caspian offshore part of the basin. (Author)

  15. Sediment-hosted micro-disseminated gold mineralization constrained by basin paleo-topographic highs in the Youjiang basin, South China

    Science.gov (United States)

    Liu, Jianming; Ye, Jie; Ying, Hanlong; Liu, Jiajun; Zheng, Minghua; Gu, Xuexiang

    2002-06-01

    The Youjiang basin is a Devonian-Triassic rift basin on the southern margin of the Yangtze Craton in South China. Strong syndepositional faulting defined the basin-and-range style paleo-topography that further developed into isolated carbonate platforms surrounded by siliciclastic filled depressions. Finally, thick Triassic siliciclastic deposits covered the platforms completely. In the Youjiang basin, numerous sediment-hosted, micro-disseminated gold (SMG) deposits occur mainly in Permian-Triassic chert and siliciclastic rocks. SMG ores are often auriferous sedimentary rocks with relatively low sulfide contents and moderate to weak alteration. Similar to Carlin-type gold ores in North America, SMG ores in the Youjiang basin are characterized by low-temperature mineral assemblages of pyrite, arsenopyrite, realgar, stibnite, cinnabar, marcasite, chalcedony and carbonate. Most of the SMG deposits are remarkably distributed around the carbonate platforms. Accordingly, there are platform-proximal and platform-distal SMG deposits. Platform-proximal SMG deposits often occur in the facies transition zone between the underlying platform carbonate rocks and the overlying siliciclastic rocks with an unconformity (often a paleo-karst surface) in between. In the ores and hostrocks there are abundant synsedimentary-syndiagenetic fabrics such as lamination, convolute bedding, slump texture, soft-sediment deformation etc. indicating submarine hydrothermal deposition and syndepositional faulting. Numerous fluid-escape and liquefaction fabrics imply strong fluid migration during sediment basin evolution. Such large-scale geological and fabric evidence implies that SMG ores were formed during basin evolution, probably in connection with basinal fluids. It is well known that basinal fluids (especially sediment-sourced fluids) will migrate generally (1) upwards, (2) towards basin margins or basin topographic highs, (3) and from thicker towards thinner deposits during basin evolution

  16. Constraining Basin Depth and Fault Displacement in the Malombe Basin Using Potential Field Methods

    Science.gov (United States)

    Beresh, S. C. M.; Elifritz, E. A.; Méndez, K.; Johnson, S.; Mynatt, W. G.; Mayle, M.; Atekwana, E. A.; Laó-Dávila, D. A.; Chindandali, P. R. N.; Chisenga, C.; Gondwe, S.; Mkumbwa, M.; Kalaguluka, D.; Kalindekafe, L.; Salima, J.

    2017-12-01

    The Malombe Basin is part of the Malawi Rift which forms the southern part of the Western Branch of the East African Rift System. At its southern end, the Malawi Rift bifurcates into the Bilila-Mtakataka and Chirobwe-Ntcheu fault systems and the Lake Malombe Rift Basin around the Shire Horst, a competent block under the Nankumba Peninsula. The Malombe Basin is approximately 70km from north to south and 35km at its widest point from east to west, bounded by reversing-polarity border faults. We aim to constrain the depth of the basin to better understand displacement of each border fault. Our work utilizes two east-west gravity profiles across the basin coupled with Source Parameter Imaging (SPI) derived from a high-resolution aeromagnetic survey. The first gravity profile was done across the northern portion of the basin and the second across the southern portion. Gravity and magnetic data will be used to constrain basement depths and the thickness of the sedimentary cover. Additionally, Shuttle Radar Topography Mission (SRTM) data is used to understand the topographic expression of the fault scarps. Estimates for minimum displacement of the border faults on either side of the basin were made by adding the elevation of the scarps to the deepest SPI basement estimates at the basin borders. Our preliminary results using SPI and SRTM data show a minimum displacement of approximately 1.3km for the western border fault; the minimum displacement for the eastern border fault is 740m. However, SPI merely shows the depth to the first significantly magnetic layer in the subsurface, which may or may not be the actual basement layer. Gravimetric readings are based on subsurface density and thus circumvent issues arising from magnetic layers located above the basement; therefore expected results for our work will be to constrain more accurate basin depth by integrating the gravity profiles. Through more accurate basement depth estimates we also gain more accurate displacement

  17. Stratigraphy of the Caloris Basin, Mercury: Implications for Volcanic History and Basin Impact Melt

    Science.gov (United States)

    Ernst, Carolyn M.; Denevi, Brett W.; Barnouin, Olivier S.; Klimczak, Christian; Chabot, Nancy L.; Head, James W.; Murchie, Scott L.; Neumann, Gregory A.; Prockter, Louis M.; Robinson, Mark S.; hide

    2015-01-01

    Caloris basin, Mercury's youngest large impact basin, is filled by volcanic plains that are spectrally distinct from surrounding material. Post-plains impact craters of a variety of sizes populate the basin interior, and the spectra of the material they have excavated enable the thickness of the volcanic fill to be estimated and reveal the nature of the subsurface. The thickness of the interior volcanic plains is consistently at least 2.5 km, reaching 3.5 km in places, with thinner fill toward the edge of the basin. No systematic variations in fill thickness are observed with long-wavelength topography or azimuth. The lack of correlation between plains thickness and variations in elevation at large horizontal scales within the basin indicates that plains emplacement must have predated most, if not all, of the changes in long-wavelength topography that affected the basin. There are no embayed or unambiguously buried (ghost) craters with diameters greater than 10 km in the Caloris interior plains. The absence of such ghost craters indicates that one or more of the following scenarios must hold: the plains are sufficiently thick to have buried all evidence of craters that formed between the Caloris impact event and the emplacement of the plains; the plains were emplaced soon after basin formation; or the complex tectonic deformation of the basin interior has disguised wrinkle-ridge rings localized by buried craters. That low-reflectance material (LRM) was exposed by every impact that penetrated through the surface volcanic plains provides a means to explore near-surface stratigraphy. If all occurrences of LRM are derived from a single layer, the subsurface LRM deposit is at least 7.5-8.5 km thick and its top likely once made up the Caloris basin floor. The Caloris-forming impact would have generated a layer of impact melt 3-15 km thick; such a layer could account for the entire thickness of LRM. This material would have been derived from a combination of lower crust

  18. Tectonic setting of Cretaceous basins on the NE Tibetan Plateau: Insights from the Jungong basin

    Science.gov (United States)

    Craddock, W.H.; Kirby, E.; Dewen, Z.; Jianhui, L.

    2012-01-01

    Quantifying the Cenozoic growth of high topography in the Indo-Asian collision zone remains challenging, due in part to significant shortening that occurred within Eurasia before collision. A growing body of evidence suggests that regions far removed from the suture zone experienced deformation before and during the early phases of Himalayan orogenesis. In the present-day north-eastern Tibetan Plateau, widespread deposits of Cretaceous sediment attest to significant basin formation; however, the tectonic setting of these basins remains enigmatic. We present a study of a regionally extensive network of sedimentary basins that are spatially associated with a system of SE-vergent thrust faults and are now exposed in the high ranges of the north-eastern corner of the Tibetan Plateau. We focus on a particularly well-exposed basin, located ~20km north of the Kunlun fault in the Anyemaqen Shan. The basin is filled by ~900m of alluvial sediments that become finer-grained away from the basin-bounding fault. Additionally, beds in the proximal footwall of the basin-bounding fault exhibit progressive, up-section shallowing and several intraformational unconformities which can be traced into correlative conformities in the distal part of the basin. The observations show sediment accumulated in the basin during fault motion. Regional constraints on the timing of sediment deposition are provided by both fossil assemblages from the Early Cretaceous, and by K-Ar dating of volcanic rocks that floor and cross-cut sedimentary fill. We argue that during the Cretaceous, the interior NE Tibetan Plateau experienced NW-SE contractional deformation similar to that documented throughout the Qinling-Dabie orogen to the east. The Songpan-Ganzi terrane apparently marked the southern limit of this deformation, such that it may have been a relatively rigid block in the Tibetan lithosphere, separating regions experiencing deformation north of the convergent Tethyan margin from regions deforming

  19. Probing the basins of attraction of a recurrent neural network

    NARCIS (Netherlands)

    Heerema, M.; van Leeuwen, W.A.

    2000-01-01

    Analytical expressions for the weights $w_{ij}(b)$ of the connections of a recurrent neural network are found by taking explicitly into account basins of attraction, the size of which is characterized by a basin parameter $b$. It is shown that a network with $b \

  20. Tritium Concentration in the F- and H-Area Seeplines and Fourmile Branch at SRS: September 1997 Event and 1989-1997 Summary

    International Nuclear Information System (INIS)

    Koch, J.

    1999-01-01

    The Environmental Analysis Section (EAS) of the Savannah River Technology Center (SRTC) conducted a quarterly monitoring program of the Fourmile Branch (FMB) stream and its associated seepline located down gradient form the F- and H-Area Seepage Basins from May 1992 to May 1995. This report presents the results of the second semi-annual event in 1997 and summarizes the tritium data beginning with the 1989 and 1992 baseline sampling events

  1. Monitoring of the water levels in the wetlands of Fourmile Branch near the F and H Areas of SRS: September 1997 to December 1998

    International Nuclear Information System (INIS)

    Halverson, N.V.

    2000-01-01

    A network of twenty-three piezometers was used to measure hydraulic head in the water-table aquifer along the groundwater outcrop (i.e. seepline) at the F- and H-Area seeplines. The piezometers were installed to assess potential impacts of the F- and H-Area Groundwater Remediation Waste Treatment Units on the riparian wetland system located between the former F- and H-Area seepage basins and Fourmile Branch

  2. Spatial Preference Heterogeneity for Integrated River Basin Management: The Case of the Shiyang River Basin, China

    Directory of Open Access Journals (Sweden)

    Fanus Asefaw Aregay

    2016-09-01

    Full Text Available Integrated river basin management (IRBM programs have been launched in most parts of China to ease escalating environmental degradation. Meanwhile, little is known about the benefits from and the support for these programs. This paper presents a case study of the preference heterogeneity for IRBM in the Shiyang River Basin, China, as measured by the Willingness to Pay (WTP, for a set of major restoration attributes. A discrete choice analysis of relevant restoration attributes was conducted. The results based on a sample of 1012 households in the whole basin show that, on average, there is significant support for integrated ecological restoration as indicated by significant WTP for all ecological attributes. However, residential location induced preference heterogeneities are prevalent. Generally, compared to upper-basin residents, middle sub-basin residents have lower mean WTP while lower sub-basin residents express higher mean WTP. The disparity in utility is partially explained by the difference in ecological and socio-economic status of the residents. In conclusion, estimating welfare benefit of IRBM projects based on sample responses from a specific sub-section of the basin only may either understate or overstate the welfare estimate.

  3. Stream seepage and groundwater levels, Wood River Valley, south-central Idaho, 2012-13

    Science.gov (United States)

    Bartolino, James R.

    2014-01-01

    Stream discharge and water levels in wells were measured at multiple sites in the Wood River Valley, south-central Idaho, in August 2012, October 2012, and March 2013, as a component of data collection for a groundwater-flow model of the Wood River Valley aquifer system. This model is a cooperative and collaborative effort between the U.S. Geological Survey and the Idaho Department of Water Resources. Stream-discharge measurements for determination of seepage were made during several days on three occasions: August 27–28, 2012, October 22–24, 2012, and March 27–28, 2013. Discharge measurements were made at 49 sites in August and October, and 51 sites in March, on the Big Wood River, Silver Creek, their tributaries, and nearby canals. The Big Wood River generally gains flow between the Big Wood River near Ketchum streamgage (13135500) and the Big Wood River at Hailey streamgage (13139510), and loses flow between the Hailey streamgage and the Big Wood River at Stanton Crossing near Bellevue streamgage (13140800). Shorter reaches within these segments may differ in the direction or magnitude of seepage or may be indeterminate because of measurement uncertainty. Additional reaches were measured on Silver Creek, the North Fork Big Wood River, Warm Springs Creek, Trail Creek, and the East Fork Big Wood River. Discharge measurements also were made on the Hiawatha, Cove, District 45, Glendale, and Bypass Canals, and smaller tributaries to the Big Wood River and Silver Creek. Water levels in 93 wells completed in the Wood River Valley aquifer system were measured during October 22–24, 2012; these wells are part of a network established by the U.S. Geological Survey in 2006. Maps of the October 2012 water-table altitude in the unconfined aquifer and the potentiometric-surface altitude of the confined aquifer have similar topology to those on maps of October 2006 conditions. Between October 2006 and October 2012, water-table altitude in the unconfined aquifer rose by

  4. Back Analysis of the Permeability Coefficient of a High Core Rockfill Dam Based on a RBF Neural Network Optimized Using the PSO Algorithm

    Directory of Open Access Journals (Sweden)

    Shichun Chi

    2015-01-01

    Full Text Available It is important to determine the seepage field parameters of a high core rockfill dam using the seepage data obtained during operation. For the Nuozhadu high core rockfill dam, a back analysis model is proposed using the radial basis function neural network optimized using a particle swarm optimization algorithm (PSO-RBFNN and the technology of finite element analysis for solving the saturated-unsaturated seepage field. The recorded osmotic pressure curves of osmometers, which are distributed in the maximum cross section, are applied to this back analysis. The permeability coefficients of the dam materials are retrieved using the measured seepage pressure values while the steady state seepage condition exists; that is, the water lever remains unchanged. Meanwhile, the parameters are tested using the unstable saturated-unsaturated seepage field while the water level rises. The results show that the permeability coefficients are reasonable and can be used to study the real behavior of a seepage field of a high core rockfill dam during its operation period.

  5. Model evaluation of seepage from uranium tailings disposal above and below the water table

    International Nuclear Information System (INIS)

    Nelson, R.W.; Meyer, P.R.; Oberlander, P.L.; Sneider, S.C.; Mayer, D.W.; Reisenauer, A.E.

    1983-03-01

    Model simulations identify the rate and amount of leachate released to the environment if disposed uranium mill tailings come into contact with ground water or if seepage from tailings reaches ground water. In this study, simulations of disposal above and below the water table, with various methods of leachate control, were compared. Three leachate control methods were used in the comparisons: clay bottom liners; stub-sidewall clay liners; and tailings drains with sumps, with the effluent pumped back from the sumps. The best leachate control for both above and below the water table is a combination of the three methods. The combined methods intercept up to 80% of the leachate volume in pits above the water table and intercept essentially all of the leachate in pits below the water table. Effluent pumping, however, requires continuous energy costs and an alternative method of disposal for the leachate that cannot be reused as makeup water in the mill process. Without the drains or effluent pumping, the clay bottom liners have little advantage in terms of the total volume of leachate lost. The clay liners do reduce the rate of leachate flow to the ground water, but the flow continues for a longer time. The buffering, sorption, and chemical reactions of the leachate passing directly through the liner are also advantages of the liner

  6. The evolution and performance of river basin management in the Murray-Darling Basin

    Directory of Open Access Journals (Sweden)

    Andrew Ross

    2016-09-01

    Full Text Available We explore bioregional management in the Murray-Darling Basin (MDB in Australia through the institutional design characteristics of the MDB River Basin Organization (RBO, the actors and organizations who supported and resisted the establishment of the RBO, and the effectiveness of the RBO. During the last 25 years, there has been a major structural reform in the MDB RBO, which has changed from an interstate coordinating body to an Australian government agency. Responsibility for basin management has been centralized under the leadership of the Australian government, and a comprehensive integrated Basin plan has been adopted. The driving forces for this centralization include national policy to restore river basins to sustainable levels of extraction, state government difficulties in reversing overallocation of water entitlements, the millennium drought and its effects, political expediency on the part of the Australian government and state governments, and a major injection of Australian government funding. The increasing hierarchy and centralization of the MDB RBO does not follow a general trend toward multilevel participative governance of RBOs, but decentralization should not be overstated because of the special circumstances at the time of the centralization and the continuing existence of some decentralized elements, such as catchment water plans, land use planning, and water quality. Further swings in the centralization-decentralization pendulum could occur. The MDB reform has succeeded in rebalancing Basin water allocations, including an allocation for the environment and reduced diversion limits. There are some longer term risks to the implementation of reform, including lack of cooperation by state governments, vertical coordination difficulties, and perceived reductions in the accountability and legitimacy of reform at the local level. If implementation of the Basin plan is diverted or delayed, a new institution, the Commonwealth

  7. PAHs distribution in sediments associated with gas hydrate and oil seepage from the Gulf of Mexico.

    Science.gov (United States)

    Wang, Cuiping; Sun, Hongwen; Chang, Ying; Song, Zhiguang; Qin, Xuebo

    2011-12-01

    Six sediment samples collected from the Gulf of Mexico were analyzed. Total concentrations of the PAHs ranged from 52 to 403 ng g(-1) dry weight. The lowest PAH concentration without 5-6 rings PAHs appeared in S-1 sample associated with gas hydrate or gas venting. Moreover, S-1 sample had the lowest organic carbon content with 0.85% and highest reduced sulfur level with 1.21% relative to other samples. And, analysis of the sources of PAHs in S-1 sample indicated that both pyrogenic and petrogenic sources, converserly, while S-8, S-10 and S-11 sample suggested petrogenic origin. The distribution of dibenzothiophene, fluorine and dibenzofuran and the maturity parameters of triaromatic steranes suggested that organic matters in S-1 sample were different from that in S-8, S-10 and S-11 sample. This study suggested that organic geochemical data could help in distinguish the characteristic of sediment associated with gas hydrate or with oil seepage. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Radium 228 as a tracer of basin wide processes in the Abyssal Ocean

    International Nuclear Information System (INIS)

    Sarmiento, J.L.; Rooth, C.G.H.; Broecker, W.S.

    1982-01-01

    A simple model of isopycnal mixing in a circular basin is developed in order to examine the utility of the 5.75-year half-life tracer radium 228 for studying basin wide processes in the deep ocean. The model shows that it is possible to resolve diffusivities of 7 cm 2 s - 1 in a basin of approx.3000-km diameter with profiles measured near the center and edge of the basin. A least squares fit of the model to four abyssal profiles measured during GEOSECS in the North American Basin gives an isopycnal diffusivity of 6 x 10 7 cm 2 s - 1

  9. Misrepresenting the Jordan River Basin

    Directory of Open Access Journals (Sweden)

    Clemens Messerschmid

    2015-06-01

    Full Text Available This article advances a critique of the UN Economic and Social Commission for West Asia’s (ESCWA’s representation of the Jordan River Basin, as contained in its recently published Inventory of Shared Water Resources in Western Asia. We argue that ESCWA’s representation of the Jordan Basin is marked by serious technical errors and a systematic bias in favour of one riparian, Israel, and against the Jordan River’s four Arab riparians. We demonstrate this in relation to ESCWA’s account of the political geography of the Jordan River Basin, which foregrounds Israel and its perspectives and narratives; in relation to hydrology, where Israel’s contribution to the basin is overstated, whilst that of Arab riparians is understated; and in relation to development and abstraction, where Israel’s transformation and use of the basin are underplayed, while Arab impacts are exaggerated. Taken together, this bundle of misrepresentations conveys the impression that it is Israel which is the main contributor to the Jordan River Basin, Arab riparians its chief exploiters. This impression is, we argue, not just false but also surprising, given that the Inventory is in the name of an organisation of Arab states. The evidence discussed here provides a striking illustration of how hegemonic hydro-political narratives are reproduced, including by actors other than basin hegemons themselves.

  10. A MATLAB®-based program for 3D visualization of stratigraphic setting and subsidence evolution of sedimentary basins: example application to the Vienna Basin

    Science.gov (United States)

    Lee, Eun Young; Novotny, Johannes; Wagreich, Michael

    2015-04-01

    In recent years, 3D visualization of sedimentary basins has become increasingly popular. Stratigraphic and structural mapping is highly important to understand the internal setting of sedimentary basins. And subsequent subsidence analysis provides significant insights for basin evolution. This study focused on developing a simple and user-friendly program which allows geologists to analyze and model sedimentary basin data. The developed program is aimed at stratigraphic and subsidence modelling of sedimentary basins from wells or stratigraphic profile data. This program is mainly based on two numerical methods; surface interpolation and subsidence analysis. For surface visualization four different interpolation techniques (Linear, Natural, Cubic Spline, and Thin-Plate Spline) are provided in this program. The subsidence analysis consists of decompaction and backstripping techniques. The numerical methods are computed in MATLAB® which is a multi-paradigm numerical computing environment used extensively in academic, research, and industrial fields. This program consists of five main processing steps; 1) setup (study area and stratigraphic units), 2) loading of well data, 3) stratigraphic modelling (depth distribution and isopach plots), 4) subsidence parameter input, and 5) subsidence modelling (subsided depth and subsidence rate plots). The graphical user interface intuitively guides users through all process stages and provides tools to analyse and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the visualization results using the full range of available plot options in MATLAB. All functions of this program are illustrated with a case study of Miocene sediments in the Vienna Basin. The basin is an ideal place to test this program, because sufficient data is

  11. Quality Assurance Project Plan for the treatability study of in situ vitrification of Seepage Pit 1 in Waste Area Grouping 7 at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    1995-07-01

    This Quality Assurance Project Plan (QAPjP) establishes the quality assurance procedures and requirements to be implemented for the control of quality-related activities for Phase 3 of the Treatability Study (TS) of In Situ Vitrification (ISV) of Seepage Pit 1, ORNL Waste Area Grouping 7. This QAPjP supplements the Quality Assurance Plan for Oak Ridge National Laboratory Environmental Restoration Program by providing information specific to the ISV-TS. Phase 3 of the TS involves the actual ISV melt operations and posttest monitoring of Pit 1 and vicinity. Previously, Phase 1 activities were completed, which involved determining the boundaries of Pit 1, using driven rods and pipes and mapping the distribution of radioactivity using logging tools within the pipes. Phase 2 involved sampling the contents, both liquid and solids, in and around seepage Pit 1 to determine their chemical and radionuclide composition and the spatial distribution of these attributes. A separate QAPjP was developed for each phase of the project. A readiness review of the Phase 3 activities presented QAPjP will be conducted prior to initiating field activities, and an Operational Acceptance, Test (OAT) will also be conducted with no contamination involved. After, the OAT is complete, the ISV process will be restarted, and the melt will be allowed to increase with depth and incorporate the radionuclide contamination at the bottom of Pit 1. Upon completion of melt 1, the equipment will be shut down and mobilized to an adjacent location at which melt 2 will commence

  12. Multitracer studies for determining seepage water and anion movement in four types of soil using lysimeters with different functions and designs

    International Nuclear Information System (INIS)

    Knappe, S.; Russow, R.

    1999-01-01

    Lysimeter experiments based on the stable isotope tracer technique are a suitable means of examining the complex relationships governing water and material transport processes in the soil. The present paper reports on experiments in which water and nitrate movement was traced directly by means of lysimeters placed at different depths and using deuterium water and [ 15 N]N-nitrate for pulse marking. Extensive investigations carried out during the dissection of soil monoliths that had been used for many years in lysimeters offered an opportunity for stable isotope tracer studies aimed at determining seepage water and anion movement in undisturbed soils and, after dismantling the lysimeters, conducting soil analyses to find out more about the fate of nonpercolated tracers at various soil depths. Following other authors, bromide anions were additionally used as conservative tracers [de

  13. Soil erosion assessment of a Himalayan river basin using TRMM data

    Science.gov (United States)

    Pandey, A.; Mishra, S. K.; Gautam, A. K.; Kumar, D.

    2015-04-01

    In this study, an attempt has been made to assess the soil erosion of a Himalayan river basin, the Karnali basin, Nepal, using rainfall erosivity (R-factor) derived from satellite-based rainfall estimates (TRMM-3B42 V7). Average annual sediment yield was estimated using the well-known Universal Soil Loss Equation (USLE). The eight-year annual average rainfall erosivity factor (R) for the Karnali River basin was found to be 2620.84 MJ mm ha-1 h-1 year-1. Using intensity-erosivity relationships and eight years of the TRMM daily rainfall dataset (1998-2005), average annual soil erosion was also estimated for Karnali River basin. The minimum and maximum values of the rainfall erosivity factor were 1108.7 and 4868.49 MJ mm ha-1 h-1 year-1, respectively, during the assessment period. The average annual soil loss of the Karnali River basin was found to be 38.17 t ha-1 year-1. Finally, the basin area was categorized according to the following scale of erosion severity classes: Slight (0 to 5 t ha-1 year-1), Moderate (5 to 10 t ha-1 year-1), High (10 to 20 t ha-1 year-1), Very High (20 to 40 t ha-1 year-1), Severe (40 to 80 t ha-1 year-1) and Very Severe (>80 t ha-1 year-1). About 30.86% of the river basin area was found to be in the slight erosion class. The areas covered by the moderate, high, very high, severe and very severe erosion potential zones were 13.09%, 6.36%, 11.09%, 22.02% and 16.64% respectively. The study revealed that approximately 69% of the Karnali River basin needs immediate attention from a soil conservation point of view.

  14. Mechanical model of water inrush from coal seam floor based on triaxial seepage experiments

    Institute of Scientific and Technical Information of China (English)

    Yihui Pang; Guofa Wang; Ziwei Ding

    2014-01-01

    In order to study the mechanism of confined water inrush from coal seam floor, the main influences on permeability in the process of triaxial seepage experiments were analyzed with methods such as laboratory experiments, theoretical analysis and mechanical model calculation. The crack extension rule and the ultimate destruction form of the rock specimens were obtained. The mechanism of water inrush was explained reasonably from mechanical point of view. The practical criterion of water inrush was put forward. The results show that the rock permeability ‘‘mutation’’ phe-nomenon reflects the differences of stress state and cracks extension rate when the rock internal crack begins to extend in large-scale. The rock ultimate destruction form is related to the rock lithology and the angle between crack and principal stress. The necessary condition of floor water inrush is that the mining pressure leads to the extension and transfixion of the crack. The sufficient condition of floor water inrush is that the confined water’s expansionary stress in normal direction and shear stress in tangential direction must be larger than the internal stress in the crack. With the two conditions satisfied at the same time, the floor water inrush accident will occur.

  15. Sustaining Exploration in Mature Basins

    International Nuclear Information System (INIS)

    Bayo, A.

    2002-01-01

    Exploration is a business like any other business driven by opportunity, resources and expectation of profit. Therefore, exploration will thrive anywhere the opportunities are significant, the resources are available and the outlook for profit (or value creation) is good. To sustain exploration activities anywhere, irrespective of the environment, there must be good understanding of the drivers of these key investment criteria. This paper will examine these investment criteria as they relate to exploration business and address the peculiarity of exploration in mature basin. Mature basins are unique environment that lends themselves a mix of fears, paradigms and realities, particularly with respect to the perception of value. To sustain exploration activities in a mature basin, we need to understand these perceptions relative to the true drivers of profitability. Exploration in the mature basins can be as profitable as exploration in emerging basins if the dynamics of value definition-strategic and fiscal values are understood by operators, regulators and co ventures alike. Some suggestions are made in this presentation on what needs to be done in addressing these dynamic investment parameters and sustaining exploration activities in mature basins

  16. Neoproterozoic rift basins and their control on the development of hydrocarbon source rocks in the Tarim Basin, NW China

    Science.gov (United States)

    Zhu, Guang-You; Ren, Rong; Chen, Fei-Ran; Li, Ting-Ting; Chen, Yong-Quan

    2017-12-01

    The Proterozoic is demonstrated to be an important period for global petroleum systems. Few exploration breakthroughs, however, have been obtained on the system in the Tarim Basin, NW China. Outcrop, drilling, and seismic data are integrated in this paper to focus on the Neoproterozoic rift basins and related hydrocarbon source rocks in the Tarim Basin. The basin consists of Cryogenian to Ediacaran rifts showing a distribution of N-S differentiation. Compared to the Cryogenian basins, those of the Ediacaran are characterized by deposits in small thickness and wide distribution. Thus, the rifts have a typical dual structure, namely the Cryogenian rifting and Ediacaran depression phases that reveal distinct structural and sedimentary characteristics. The Cryogenian rifting basins are dominated by a series of grabens or half grabens, which have a wedge-shaped rapid filling structure. The basins evolved into Ediacaran depression when the rifting and magmatic activities diminished, and extensive overlapping sedimentation occurred. The distributions of the source rocks are controlled by the Neoproterozoic rifts as follows. The present outcrops lie mostly at the margins of the Cryogenian rifting basins where the rapid deposition dominates and the argillaceous rocks have low total organic carbon (TOC) contents; however, the source rocks with high TOC contents should develop in the center of the basins. The Ediacaran source rocks formed in deep water environment of the stable depressions evolving from the previous rifting basins, and are thus more widespread in the Tarim Basin. The confirmation of the Cryogenian to Ediacaran source rocks would open up a new field for the deep hydrocarbon exploration in the Tarim Basin.

  17. Hydrology of Quirke and Panel uranium tailings basins

    International Nuclear Information System (INIS)

    King, R.M.; MacPhie, L.

    1991-11-01

    The research project described by this report provides the AECB with an independent assessment of the 'saturated tailings concept' for the decommissioning of tailing areas at the Rio Algom Quirke and Panel uranium mines near Elliot Lake in Northern Ontario. Hydrologic and hydraulic modelling for each facility showed the interrelation between the design of the water-level control facilities and the water levels in each cell for design flood and extreme low-flow conditions, taking into account all water-balance components. The estimate of seepage rates through the tailings mass is identified as a critical issue

  18. A stochastic approach for the description of the water balance dynamics in a river basin

    Directory of Open Access Journals (Sweden)

    S. Manfreda

    2008-09-01

    Full Text Available The present paper introduces an analytical approach for the description of the soil water balance dynamics over a schematic river basin. The model is based on a stochastic differential equation where the rainfall forcing is interpreted as an additive noise in the soil water balance. This equation can be solved assuming known the spatial distribution of the soil moisture over the basin transforming the two-dimensional problem in space in a one dimensional one. This assumption is particularly true in the case of humid and semihumid environments, where spatial redistribution becomes dominant producing a well defined soil moisture pattern. The model allowed to derive the probability density function of the saturated portion of a basin and of its relative saturation. This theory is based on the assumption that the soil water storage capacity varies across the basin following a parabolic distribution and the basin has homogeneous soil texture and vegetation cover. The methodology outlined the role played by the soil water storage capacity distribution of the basin on soil water balance. In particular, the resulting probability density functions of the relative basin saturation were found to be strongly controlled by the maximum water storage capacity of the basin, while the probability density functions of the relative saturated portion of the basin are strongly influenced by the spatial heterogeneity of the soil water storage capacity. Moreover, the saturated areas reach their maximum variability when the mean rainfall rate is almost equal to the soil water loss coefficient given by the sum of the maximum rate of evapotranspiration and leakage loss in the soil water balance. The model was tested using the results of a continuous numerical simulation performed with a semi-distributed model in order to validate the proposed theoretical distributions.

  19. Spent LWR fuel storage costs: reracking, AR basins, and AFR basins

    International Nuclear Information System (INIS)

    1980-01-01

    Whenever possible, fuel storage requirements will be met by reracking existing reactor basins and/or transfer of fuel to available space in other reactor basins. These alternatives represent not only the lowest cost storage options but also the most timely. They are recognized to face environmental and regulatory obstacles. However, such obstacles should be less severe than those that would be encountered with AR or AFR basin storage. When storage requirements cannot be met by the first two options, the least costly alternative for most utilities will be use of a Federal AFR. Storage costs of $100,000 to $150,000 MTU at a AFR are less costly than charges of up to $320,000/MTU that could be incurred by the use of AR basins. AFR storage costs do not include transportation from the reactor to the AFR. This cost would be paid by the utility separately. Only when a utility requires annual storage capacity for 100 MTU of spent fuel can self-storage begin to compete with AFR costs. The large reactor complexes discharging these fuel quantities are not currently those that require relief from fuel storage problems

  20. Terminal Fluvial Systems in a Semi-arid Endorheic Basin, Salar de Uyuni (Bolivia)

    NARCIS (Netherlands)

    Li, J.

    2014-01-01

    Many ancient sedimentary basins are interpreted as endorheic basins, internally drained basins with no direct hydrological connection to the marine environment. Some of these endorheic basins are economically important because of the abundance of hydrocarbon resources. To date, many studies have

  1. Geologic Basin Boundaries (Basins_GHGRP) GIS Layer

    Data.gov (United States)

    U.S. Environmental Protection Agency — This is a coverage shapefile of geologic basin boundaries which are used by EPA's Greenhouse Gas Reporting Program. For onshore production, the "facility" includes...

  2. L-Reactor 186-basin cleaning alternatives

    International Nuclear Information System (INIS)

    Turcotte, M.D.S.

    1983-01-01

    Operation of L Reactor will necessitate annual cleaning of the L Area 186 basins. Alternatives are presented for sediment discharge due to 186-basin cleaning activities as a basis for choosing the optimal cleaning method. Current cleaning activities (i.e. removal of accumulated sediments) for the P, C and K-Area 186 basins result in suspended solids concentrations in the effluent waters above the NPDES limits, requiring an exemption from the NPDES permit for these short-term releases. The objective of mitigating the 186-basin cleaning activities is to decrease the suspended solids concentrations to within permit limits while continuing satisfactory operation of the basins

  3. Evolution of the Rembrandt impact basin on Mercury.

    Science.gov (United States)

    Watters, Thomas R; Head, James W; Solomon, Sean C; Robinson, Mark S; Chapman, Clark R; Denevi, Brett W; Fassett, Caleb I; Murchie, Scott L; Strom, Robert G

    2009-05-01

    MESSENGER's second Mercury flyby revealed a ~715-kilometer-diameter impact basin, the second-largest well-preserved basin-scale impact structure known on the planet. The Rembrandt basin is comparable in age to the Caloris basin, is partially flooded by volcanic plains, and displays a unique wheel-and-spoke-like pattern of basin-radial and basin-concentric wrinkle ridges and graben. Stratigraphic relations indicate a multistaged infilling and deformational history involving successive or overlapping phases of contractional and extensional deformation. The youngest deformation of the basin involved the formation of a approximately 1000-kilometer-long lobate scarp, a product of the global cooling and contraction of Mercury.

  4. Crustal characteristic variation in the central Yamato Basin, Japan Sea back-arc basin, deduced from seismic survey results

    Science.gov (United States)

    Sato, Takeshi; No, Tetsuo; Miura, Seiichi; Kodaira, Shuichi

    2018-02-01

    The crustal structure of the Yamato Bank, the central Yamato Basin, and the continental shelf in the southern Japan Sea back-arc basin is obtained based on a seismic survey using ocean bottom seismographs and seismic shot to elucidate the back-arc basin formation processes. The central Yamato Basin can be divided into three domains based on the crustal structure: the deep basin, the seamount, and the transition domains. In the deep basin domain, the crust without the sedimentary layer is about 12-13 km thick. Very few units have P-wave velocity of 5.4-6.0 km/s, which corresponds to the continental upper crust. In the seamount and transition domains, the crust without the sedimentary layer is about 12-16 km thick. The P-wave velocities of the upper and lower crusts differs among the deep basin, the seamount, and the transition domains. These results indicate that the central Yamato Basin displays crustal variability in different domains. The crust of the deep basin domain is oceanic in nature and suggests advanced back-arc basin development. The seamount domain might have been affected by volcanic activity after basin opening. In the transition domain, the crust comprises mixed characters of continental and oceanic crust. This crustal variation might represent the influence of different processes in the central Yamato Basin, suggesting that crustal development was influenced not only by back-arc opening processes but also by later volcanic activity. In the Yamato Bank and continental shelf, the upper crust has thickness of about 17-18 km and P-wave velocities of 3.3-4.1 to 6.6 km/s. The Yamato Bank and the continental shelf suggest a continental crustal character.

  5. Melo carboniferous basin

    International Nuclear Information System (INIS)

    Flossdarf, A.

    1988-01-01

    This report is about of the Melo carboniferous basin which limits are: in the South the large and high Tupambae hill, in the west the Paraiso hill and the river mountains, in the North Yaguaron river basin to Candidata in Rio Grande del Sur in Brazil.

  6. A method for developing a large-scale sediment yield index for European river basins

    Energy Technology Data Exchange (ETDEWEB)

    Delmas, Magalie; Cerdan, Olivier; Garcin, Manuel [BRGM ARN/ESL, Orleans (France); Mouchel, Jean-Marie [UMR Sisyphe, Univ. P and M Curie, Paris (France)

    2009-12-15

    Background, aim, and scope: Sediment fluxes within continental areas play a major role in biogeochemical cycles and are often the cause of soil surface degradation as well as water and ecosystem pollution. In a situation where a high proportion of the land surface is experiencing significant global land use and climate changes, it appears important to establish sediment budgets considering the major processes forcing sediment redistribution within drainage areas. In this context, the aim of this study is to test a methodology to estimate a sediment yield index at a large spatial resolution for European river basins. Data and methods: Four indicators representing processes respectively considered as sources (mass movement and hillslope erosion), sinks (deposits), and transfers of sediments (drainage density) are defined using distributed data. Using these indicators we propose a basic conceptual approach to test the possibility of explaining sediment yield observed at the outlet of 29 selected European river basins. We propose an index which adds the two sources and transfers, and subsequently subtracts the sink term. This index is then compared to observed sediment yield data. Results: With this approach, variability between river basins is observed and the evolution of each indicator analyzed. A linear regression shows a correlation coefficient of 0.83 linking observed specific sediment yield (SSY) with the SSY index. Discussion: To improve this approach at this large river basin scale, basin classification is further refined using the relation between the observed SSY and the index obtained from the four indicators. It allows a refinement of the results. Conclusions: This study presents a conceptual approach offering the advantages of using spatially distributed data combined with major sediment redistribution processes to estimate the sediment yield observed at the outlet of river basins. Recommendations and perspectives: Inclusion of better information on

  7. Area environmental characterization report of the Dalhart and Palo Duro basins in the Texas Panhandle. Volume I. Dalhart Basin

    International Nuclear Information System (INIS)

    1982-09-01

    This area report describes the environmental characteristics of the Dalhart and Palo Duro basins of the Texas Panhandle portion of the Permian basin. Both basins are rather sparsely populated, and the overall population is decreasing. The economic base is centered on agribusiness and manufacturing. Most of the potentially conflicting land uses in both basins (i.e., parks, historic sites) occupy small land areas, with the exception of a national grassland in the Dalhart and military air training routes in both basins. Ground transportation in the Dalhart basin is adequate, and it is well developed in the Palo Duro basin. In both basins irrigation constitutes the principal water use, and groundwater is the principal source. However, the dominant aquifer, the Ogallala, is being depleted. Both basins consist primarily of grasslands, rangelands, and agricultural areas. No critical terrestrial or aquatic habitats have been identified in the basins, though several endangered, threatened, or rare terrestrial species occur in or near the basins. Aquatic resources in both basins are limited because of the intermittent availability of water and the high salt content of some water bodies. Playa lakes are common, though usually seasonal or rain dependent. The climate of the area is semiarid, with low humidity, relatively high wind speeds, and highly variable prcipitation. Restrictive dispersion conditions are infrequent. National ambient secondary air quality standards for particulates are being exceeded in the area, largely because of fugitive dust, although there are some particulate point sources

  8. Miocene block uplift and basin formation in the Patagonian foreland: The Gastre Basin, Argentina

    Science.gov (United States)

    Bilmes, A.; D'Elia, L.; Franzese, J. R.; Veiga, G. D.; Hernández, M.

    2013-08-01

    The intraplate fault-block mountains and intermontane deposits of the Gastre Basin, which are recorded more than 550 km east of the Andean trench in central Patagonia, Argentina, are analyzed. The Gastre Basin is one of the largest Patagonian intermontane basins, limited by uplifted blocks strongly oblique to the Andean chain. It was originated by reverse faulting and inversion of pre-existing normal faults associated with a Mesozoic rift basin and defined by older crustal heterogeneities. The deformational event occurred during the middle Miocene, related to a short contractional episode (16.1-14.86 Ma), probably in response to an eastward migration of the Andean fold and thrust belt. During Pliocene to Quaternary times, neither younger fault-block uplifts nor reconfigurations of the basin occurred. Similarities between the study area and other parts of the Patagonian foreland - such as the presence of Miocene reverse or inversion tectonics, as well as the accommodation of the Miocene sedimentary successions - suggest that the Gastre Basin is part of a major late early to middle Miocene broken foreland system (i.e. the Patagonian broken foreland) that exhumed discrete fault-block mountains and generated contemporary basins along more than 950 km parallel to the Andean trench (i.e. between 40°00' and 48°00' south latitude). Based on recent studies on the southern Andean Margin, this continental-scale contractional episode may be the result of a flat-slab subduction segment. Nevertheless, such a hypothesis is very difficult to support when analyzing such a large flat subduction segment along the entire Patagonian trench. This suggests the need to consider alternative flat-slab trigger mechanisms or other factors in the generation of broken foreland systems.

  9. Investigation of groundwater seepage from the Hanford shoreline of the Columbia River

    International Nuclear Information System (INIS)

    McCormack, W.D.; Carlile, J.M.V.

    1984-11-01

    Groundwater discharges to the Columbia River are evaluated by the Hanford Environmental Surveillance and Groundwater Surveillance Programs via monitoring of the Columbia River and Hanford groundwater. Both programs concluded that Hanford groundwater has not adversely affected Columbia River water quality. This report supplements the above programs by investigating the general characteristics of groundwater entering the Columbia River from the Hanford Site. Specific objectives of the investigation were to identify general shoreline areas where Hanford-related materials were entering the river, and to evaluate qualitatively the physical characteristics and relative magnitudes of those discharges. The study was conducted in two phases. Phase 1 involved visual inspection of Columbia River shoreline, within the Hanford Site, for indications of groundwater seepage. As a result of that inspection, 115 springs suspected of discharging groundwater were recorded. During Phase 2, water samples were collected from these springs and analyzed for Hanford-related materials known to be present in the groundwater. The specific materials used as indicators for the majority of samples were tritium or uranium and nitrate. The magnitude and distribution of concentrations measured in the spring samples were consistent with concentrations of these materials measured in groundwater near the sampled spring locations. Water samples were also collected from the Columbia River to investigate the localized effects of groundwater discharges occurring above and below river level. These samples were collected within 2 to 4 m of the Hanford shoreline and analyzed for tritium, nitrate, and uranium. Elevated concentrations were measured in river samples collected near areas where groundwater and spring concentrations were elevated. All concentrations were below applicable DOE Concentration Guides. 8 references, 6 figures, 7 tables

  10. Hydrogeological controls on spatial patterns of groundwater discharge in peatlands

    Directory of Open Access Journals (Sweden)

    D. K. Hare

    2017-11-01

    Full Text Available Peatland environments provide important ecosystem services including water and carbon storage, nutrient processing and retention, and wildlife habitat. However, these systems and the services they provide have been degraded through historical anthropogenic agricultural conversion and dewatering practices. Effective wetland restoration requires incorporating site hydrology and understanding groundwater discharge spatial patterns. Groundwater discharge maintains wetland ecosystems by providing relatively stable hydrologic conditions, nutrient inputs, and thermal buffering important for ecological structure and function; however, a comprehensive site-specific evaluation is rarely feasible for such resource-constrained projects. An improved process-based understanding of groundwater discharge in peatlands may help guide ecological restoration design without the need for invasive methodologies and detailed site-specific investigation. Here we examine a kettle-hole peatland in southeast Massachusetts historically modified for commercial cranberry farming. During the time of our investigation, a large process-based ecological restoration project was in the assessment and design phases. To gain insight into the drivers of site hydrology, we evaluated the spatial patterning of groundwater discharge and the subsurface structure of the peatland complex using heat-tracing methods and ground-penetrating radar. Our results illustrate that two groundwater discharge processes contribute to the peatland hydrologic system: diffuse lower-flux marginal matrix seepage and discrete higher-flux preferential-flow-path seepage. Both types of groundwater discharge develop through interactions with subsurface peatland basin structure, often where the basin slope is at a high angle to the regional groundwater gradient. These field observations indicate strong correlation between subsurface structures and surficial groundwater discharge. Understanding these general patterns

  11. Hydrogeological controls on spatial patterns of groundwater discharge in peatlands

    Science.gov (United States)

    Hare, Danielle K.; Boutt, David F.; Clement, William P.; Hatch, Christine E.; Davenport, Glorianna; Hackman, Alex

    2017-11-01

    Peatland environments provide important ecosystem services including water and carbon storage, nutrient processing and retention, and wildlife habitat. However, these systems and the services they provide have been degraded through historical anthropogenic agricultural conversion and dewatering practices. Effective wetland restoration requires incorporating site hydrology and understanding groundwater discharge spatial patterns. Groundwater discharge maintains wetland ecosystems by providing relatively stable hydrologic conditions, nutrient inputs, and thermal buffering important for ecological structure and function; however, a comprehensive site-specific evaluation is rarely feasible for such resource-constrained projects. An improved process-based understanding of groundwater discharge in peatlands may help guide ecological restoration design without the need for invasive methodologies and detailed site-specific investigation. Here we examine a kettle-hole peatland in southeast Massachusetts historically modified for commercial cranberry farming. During the time of our investigation, a large process-based ecological restoration project was in the assessment and design phases. To gain insight into the drivers of site hydrology, we evaluated the spatial patterning of groundwater discharge and the subsurface structure of the peatland complex using heat-tracing methods and ground-penetrating radar. Our results illustrate that two groundwater discharge processes contribute to the peatland hydrologic system: diffuse lower-flux marginal matrix seepage and discrete higher-flux preferential-flow-path seepage. Both types of groundwater discharge develop through interactions with subsurface peatland basin structure, often where the basin slope is at a high angle to the regional groundwater gradient. These field observations indicate strong correlation between subsurface structures and surficial groundwater discharge. Understanding these general patterns may allow resource

  12. Bottom water circulation in Cascadia Basin

    Science.gov (United States)

    Hautala, Susan L.; Paul Johnson, H.; Hammond, Douglas E.

    2009-10-01

    A combination of beta spiral and minimum length inverse methods, along with a compilation of historical and recent high-resolution CTD data, are used to produce a quantitative estimate of the subthermocline circulation in Cascadia Basin. Flow in the North Pacific Deep Water, from 900-1900 m, is characterized by a basin-scale anticyclonic gyre. Below 2000 m, two water masses are present within the basin interior, distinguished by different potential temperature-salinity lines. These water masses, referred to as Cascadia Basin Bottom Water (CBBW) and Cascadia Basin Deep Water (CBDW), are separated by a transition zone at about 2400 m depth. Below the depth where it freely communicates with the broader North Pacific, Cascadia Basin is renewed by northward flow through deep gaps in the Blanco Fracture Zone that feeds the lower limb of a vertical circulation cell within the CBBW. Lower CBBW gradually warms and returns to the south at lighter density. Isopycnal layer renewal times, based on combined lateral and diapycnal advective fluxes, increase upwards from the bottom. The densest layer, existing in the southeast quadrant of the basin below ˜2850 m, has an advective flushing time of 0.6 years. The total volume flushing time for the entire CBBW is 2.4 years, corresponding to an average water parcel residence time of 4.7 years. Geothermal heating at the Cascadia Basin seafloor produces a characteristic bottom-intensified temperature anomaly and plays an important role in the conversion of cold bottom water to lighter density within the CBBW. Although covering only about 0.05% of the global seafloor, the combined effects of bottom heat flux and diapycnal mixing within Cascadia Basin provide about 2-3% of the total required global input to the upward branch of the global thermohaline circulation.

  13. California Basin Studies (CaBS)

    International Nuclear Information System (INIS)

    Gorsline, D.S.

    1991-01-01

    The California Continental Borderland's present configuration dates from about 4 to 5 X 10 6 years Before Present (B.P.) and is the most recent of several configurations of the southern California margin that have evolved after the North America Plate over-rode the East Pacific Rise about 30 X 10 6 years ago. The present morphology is a series of two to three northwest-southeast trending rows of depressions separated by banks and insular ridges. Two inner basins, Santa Monica and San Pedro, have been the site for the Department of Energy-funded California Basin Study (CaBS) Santa Monica and San Pedro Basins contain post-Miocene sediment thicknesses of about 2.5 and 1.5 km respectively. During the Holocene (past 10,000 years) about 10-12 m have accumulated. The sediment entered the basin by one or a combination of processes including particle infall (mainly as bioaggregates) from surface waters, from nepheloid plumes (surface, mid-depths and near-bottom), from turbidity currents, mass movements, and to a very minor degree direct precipitation. In Santa Monica Basin, during the last century, particle infall and nepheloid plume transport have been the most common processes. The former dominates in the central basin floor in water depths from 900 to 945 m. where a characteristic silt-clay with a typical mean diameter of about 0.006 mm, phi standard deviation

  14. Comprehensive Characterization of Droughts to Assess the Effectiveness of a Basin-Wide Integrated Water Management in the Yakima River Basin

    Science.gov (United States)

    Demissie, Y.; Mortuza, M. R.; Li, H. Y.

    2017-12-01

    Better characterization and understanding of droughts and their potential links to climate and hydrologic factors are essential for water resources planning and management in drought-sensitive but agriculturally productive regions like the Yakima River Basin (YKB) in Washington State. The basin is semi-arid and heavily relies on a fully appropriated irrigation water for fruit and crop productions that worth more than 3 billion annually. The basin experienced three major droughts since 2000 with estimated 670 million losses in farm revenue. In response to these and expected worsening drought conditions in the future, there is an ongoing multi-agency effort to adopt a basin-wide integrated water management to ensure water security during severe droughts. In this study, the effectiveness of the proposed water management plan to reduce the frequency and severity of droughts was assessed using a new drought index developed based on the seasonal variations of precipitation, temperature, snow accumulation, streamflow, and reservoir storages. In order to uncover the underlying causes of the various types of droughts observed during the 1961-2016, explanatory data analysis using deep learning was conducted for the local climate and hydrologic data including total water supply available, as well as global climatic phenomenon (El Niño/Southern Oscillation, Pacific Decadal Oscillation and North Atlantic Oscillation). The preliminary results showed that besides shortage in annual precipitation, various combinations of climate and hydrologic factors are responsible for the different drought conditions in the basin. Particularly, the winter snowpack, which provides about 2/3 of the surface water in the basin along with the carryover storage from the reservoirs play an important role during both single- and multiple-year drought events. Besides providing the much-needed insights about characteristics of droughts and their contributing factors, the outcome of the study is expected

  15. New aerogeophysical study of the Eurasia Basin and Lomonosov Ridge: Implications for basin development

    DEFF Research Database (Denmark)

    Brozena, J.M.; Childers, V.A.; Lawver, L.A.

    2003-01-01

    In 1998 and 1999, new aerogeophysical surveys of the Arctic Ocean's Eurasia Basin produced the first collocated gravity and magnetic measurements over the western half of the basin. These data increase the density and extend the coverage of the U.S. Navy acromagnetic data from the 1970s. The new...... data reveal prominent bends in the isochrons that provide solid geometrical constraints for plate reconstructions. Tentative identification of anomaly 25 in the Eurasia Basin links early basin opening to spreading in the Labrador Sea before the locus of spreading in the North Atlantic shifted...... to the Norwegian-Greenland Sea. With the opening of the Labrador Sea, Greenland began similar to200 km of northward movement relative to North America and eventually collided with Svalbard, Ellesmere Island, and the nascent Eurasia ocean basin. Both gravity and magnetic data sets reconstructed to times prior...

  16. Great Basin Experimental Range: Annotated bibliography

    Science.gov (United States)

    E. Durant McArthur; Bryce A. Richardson; Stanley G. Kitchen

    2013-01-01

    This annotated bibliography documents the research that has been conducted on the Great Basin Experimental Range (GBER, also known as the Utah Experiment Station, Great Basin Station, the Great Basin Branch Experiment Station, Great Basin Experimental Center, and other similar name variants) over the 102 years of its existence. Entries were drawn from the original...

  17. Lithospheric-scale centrifuge models of pull-apart basins

    Science.gov (United States)

    Corti, Giacomo; Dooley, Tim P.

    2015-11-01

    We present here the results of the first lithospheric-scale centrifuge models of pull-apart basins. The experiments simulate relative displacement of two lithospheric blocks along two offset master faults, with the presence of a weak zone in the offset area localising deformation during strike-slip displacement. Reproducing the entire lithosphere-asthenosphere system provides boundary conditions that are more realistic than the horizontal detachment in traditional 1 g experiments and thus provide a better approximation of the dynamic evolution of natural pull-apart basins. Model results show that local extension in the pull-apart basins is accommodated through development of oblique-slip faulting at the basin margins and cross-basin faults obliquely cutting the rift depression. As observed in previous modelling studies, our centrifuge experiments suggest that the angle of offset between the master fault segments is one of the most important parameters controlling the architecture of pull-apart basins: the basins are lozenge shaped in the case of underlapping master faults, lazy-Z shaped in case of neutral offset and rhomboidal shaped for overlapping master faults. Model cross sections show significant along-strike variations in basin morphology, with transition from narrow V- and U-shaped grabens to a more symmetric, boxlike geometry passing from the basin terminations to the basin centre; a flip in the dominance of the sidewall faults from one end of the basin to the other is observed in all models. These geometries are also typical of 1 g models and characterise several pull-apart basins worldwide. Our models show that the complex faulting in the upper brittle layer corresponds at depth to strong thinning of the ductile layer in the weak zone; a rise of the base of the lithosphere occurs beneath the basin, and maximum lithospheric thinning roughly corresponds to the areas of maximum surface subsidence (i.e., the basin depocentre).

  18. On the significance of ELF basins

    Indian Academy of Sciences (India)

    Unknown

    to complement to chemical intuition (see, e.g., refs. 2, 3). In a mathematically more rigorous way, such regions, ELF basins,4 were defined following the spirit of Bader's Atoms in Molecules (AIM). All points in space which lead to the a given maximum of ELF, by following the gradient of ELF, belong to the same basin. Basins ...

  19. Transient electromagnetic study of basin fill sediments in the Upper San Pedro Basin, Mexico

    Science.gov (United States)

    Bultman, M.W.; Gray, F.

    2011-01-01

    The Upper San Pedro River Basin in Mexico and the United States is an important riparian corridor that is coming under increasing pressure from growing populations and the associated increase in groundwater withdrawal. Several studies have produced three-dimensional maps of the basin fill sediments in the US portion of the basin but little work has been done in the Mexican portion of the basin. Here, the results of a ground-based transient electromagnetic (TEM) survey in the Upper San Pedro Basin, Mexico are presented. These basin fill sediments are characterized by a 10-40 m deep unsaturated surficial zone which is composed primarily of sands and gravels. In the central portion of the basin this unsaturated zone is usually underlain by a shallow clay layer 20-50 m thick. Beneath this may be more clay, as is usually the case near the San Pedro River, or interbedded sand, silt, and clay to a depth of 200-250 m. As you move away from the river, the upper clay layer disappears and the amount of sand in the sediments increases. At 1-2 km away from the river, sands can occupy up to 50% of the upper 200-250 m of the sediment fill. Below this, clays are always present except where bedrock highs are observed. This lower clay layer begins at a depth of about 200 m in the central portion of the basin (250 m or more at distances greater than 1-2 km from the river) and extends to the bottom of most profiles to depths of 400 m. While the depth of the top of this lower clay layer is probably accurate, its thickness observed in the models may be overestimated due to the relatively low magnetic moment of the TEM system used in this study. The inversion routine used for interpretation is based on a one-dimensional geologic model. This is a layer based model that is isotropic in both the x and y directions. Several survey soundings did not meet this requirement which invalidates the inversion process and the resulting interpretation at these locations. The results from these

  20. 5. Basin assessment and watershed analysis

    Science.gov (United States)

    Leslie M. Reid; Robert R. Ziemer

    1994-01-01

    Abstract - Basin assessment is an important component of the President's Forest Plan, yet it has received little attention. Basin assessments are intended both to guide watershed analyses by specifying types of issues and interactions that need to be understood, and, eventually, to integrate the results of watershed analyses occurring within a river basin....

  1. Analysis of efficiency of pollution reduction measures in rural basin using MIKE Basin model. Case study: Olšava River Basin

    Directory of Open Access Journals (Sweden)

    Kaiglová Jana

    2014-03-01

    Full Text Available This paper presents the results of testing the applicability of the MIKE Basin model for simulating the efficiency of scenarios for reducing water pollution. The model has been tested on the Olšava River Basin (520 km2 which is a typical rural region with a heterogeneous mix of pollution sources with variable topography and land use. The study proved that the model can be calibrated successfully using even the limited amount of data typically available in rural basins. The scenarios of pollution reduction were based on implementation and intensification of municipal wastewater treatment and conversion of arable land on fields under the risk of soil erosion to permanent grassland. The application of simulation results of these scenarios with proposed measures proved decreasing concentrations in downstream monitoring stations. Due to the practical applicability of proposed measures, these could lead to fulfilment of the water pollution limits required by the Czech and EU legislation. However, there are factors of uncertainty that are discussed that may delay or limit the effect of adopted measures in small rural basins.

  2. Basalt stratigraphy - Pasco Basin

    International Nuclear Information System (INIS)

    Waters, A.C.; Myers, C.W.; Brown, D.J.; Ledgerwood, R.K.

    1979-10-01

    The geologic history of the Pasco Basin is sketched. Study of the stratigraphy of the area involved a number of techniques including major-element chemistry, paleomagnetic investigations, borehole logging, and other geophysical survey methods. Grande Ronde basalt accumulation in the Pasco Basin is described. An illustrative log response is shown. 1 figure

  3. Evolution of sedimentary architecture in retro-foreland basin: Aquitaine basin example from Paleocene to lower Eocene.

    Science.gov (United States)

    Ortega, Carole; Lasseur, Eric; Guillocheau, François; Serrano, Olivier; Malet, David

    2017-04-01

    The Aquitaine basin located in south western Europe, is a Pyrenean retro-foreland basin. Two main phases of compression are recorded in this retro-foreland basin during the Pyrenean orogeny. A first upper Cretaceous phase corresponding to the early stage of the orogeny, and a second one usually related to a Pyrenean paroxysmal phase during the middle Eocene. During Paleocene to lower Eocene deformations are less pronounced, interpreted as a tectonically quiet period. The aim of the study is to better constrain the sedimentary system of the Aquitaine basin during this period of Paleocene-lower Eocene, in order to discuss the evolution of the sedimentary architecture in response of the Pyrenean compression. This work is based on a compilation of a large set of subsurface data (wells logs, seismic lines and cores logs) represented by isopachs and facies map. Three main cycles were identified during this structural quiet period: (1) The Danian cycle, is recorded by the aggradation of carbonate reef-rimmed platform. This platform is characterized by proximal facies (oncoid carbonate and mudstone with thalassinoides) to the north, which leads to distal deposit facies southern (pelagic carbonate with globigerina and slump facies) and present a significant thickness variation linked to the platform-slope-basin morphology. (2) The upper Selandian-Thanetian cycle follows a non-depositional/erosional surface associated with a Selandian hiatus. The base of this cycle marked the transition between the last reef rimmed platform and a carbonate ramp. The transgressive cycle is characterized by proximal lagoon facies to the north that leads southward to distal hemipelagic facies interfingered by turbiditic Lowstand System Tracks (LST). The location of these LST is strongly controlled by inherited Danian topography. The regressive cycle ends with a major regression associated with an erosional surface. This surface is linked with a network of canyons in the north, an important

  4. Nova Scotia offshore to Grand Banks connection : Mesozoic basins on a transform margin

    Energy Technology Data Exchange (ETDEWEB)

    Conway, L.E.; Martin, M.R.; Enachescu, M.E.; Atkinson, I.; Stead, J.E. [Memorial Univ. of Newfoundland, St. John' s, NL (Canada). Dept. of Earth Sciences and Pan-Atlantic Petroleum Systems Consortium

    2005-07-01

    The renewed interest in the southern Grand Banks has resulted in new active exploration licenses, seismic acquisition programs and planned drilling in the South Whale and Laurentian basins. The basins are located northeast of the Scotian margin, about 200 km south of the east coast of Newfoundland, in shallow to intermediate waters in an area free of icebergs. The Scotian and Newfoundland offshore areas are separated by the St. Lawrence Tertiary channel. A provincial boundary divides the jurisdiction over sea resources. The long political moratorium which had been imposed on the Laurentian Basin was resolved during the summer of 2003 with the establishment of the provincial boundary. Some regional geological maps of the East Coast Mesozoic sedimentary area indicate continuity between the Orpheus Graben and northern Scotian Shelf and Slope basins (Nova Scotia) and Laurentian and South Whale basins (Newfoundland). In contrast, other maps represents them as being separated by faults or ridges that affect the basin development and complicate the tectono-structural framework initiated in Late Triassic-Early Jurassic periods. Argo salt features found in seismic sections on both sides of the provincial boundary indicate that Atlantic Canada basins were interconnected during the marine phase of the Thethys rifting stage, most likely up to the time of Scotian Shelf break-up. During the Late Jurassic, marine, oil prone source rocks were deposited in the Grand Banks basins and terrestrial to marine, gas prone source rocks were deposited offshore Nova Scotia. Modern industry 2D data donated by GSI and WesternGeco were used to examine the structural and stratigraphic framework of the basins. Common geological and geomorphologic features were emphasized along with the disparity between the structural element, stratigraphy and quality of petroleum systems of the two basins.

  5. Insights on the structural control of a Neogene forearc basin in Northern Chile: A geophysical approach

    Science.gov (United States)

    García-Pérez, Tiaren; Marquardt, Carlos; Yáñez, Gonzalo; Cembrano, José; Gomila, Rodrigo; Santibañez, Isabel; Maringue, José

    2018-06-01

    The comprehensive study of intramountain basins located in the Coastal Cordillera of the continental emergent Andean forearc in Northern Chile, enables the better understanding of the nature and evolution of the upper crustal deformation during the Neogene and Quaternary. A case study is the extensive extensional half-graben Alto Hospicio basin. The basin is cut by the Coastal Cliff, which exposes the deformed Neogene basin fill. Also exposed are several structural systems, some of which affect Quaternary surfaces. The results of the integrated geophysical surveys (Electromagnetic Transient and Gravity) allow us to fully constrain the geometry of the Alto Hospicio basin and the lithological relationship between the subsurface geological units. The structural geology analysis assesses the deformation regimes affecting the faults present in the basin and surrounding area. Altogether evidence a change in the deformation regime from an EW extensional deformation during the Miocene-Pliocene to a NS compression in the Quaternary as is presented in this study. We suggest this deformation change is related to a small change in the convergence vector orientation during the Pliocene.

  6. Area environmental characterization report of the Dalhart and Palo Duro basins in the Texas Panhandle. Volume II. Palo Duro basin

    International Nuclear Information System (INIS)

    1982-09-01

    This area report describes the environmental characteristics of the Dalhart and Palo Duro basins of the Texas Panhandle portion of the Permian basin. Both basins are rather sparsely populated, and the overall population is decreasing. The economic base is centered on agribusiness and manufacturing. Most of the potentially conflicting land uses in both basins (i.e., parks, historic sites) occupy small land areas, with the exception of a national grassland in the Dalhart and military air training routes in both basins. Ground transportation in the Dalhart basin is adequate, and it is well developed in the Palo Duro basin. In both basins irrigation constitutes the principal water use, and groundwater is the principal source. However, the dominant aquifer, the Ogallala, is being depleted. Both basins consist primarily of grasslands, rangelands, and agricultural areas. No critical terrestrial or aquatic habitats have been identified in the basins, though several endangered, threatened, or rare terrestrial species occur in or near the basins. Aquatic resources in both basins are limited because of the intermittent availability of water and the high salt content of some water bodies. Playa lakes are common, though usually seasonal or rain dependent. The climate of the area is semiarid, with low humidity, relatively high wind speeds, and high variable precipitation. Restrictive dispersion conditions are infrequent. National ambient secondary air quality standards for particulates are being exceeded in the area, largely because of fugitive dust, although there are some particulate point sources

  7. Nutrient mitigation in a temporary river basin.

    Science.gov (United States)

    Tzoraki, Ourania; Nikolaidis, Nikolaos P; Cooper, David; Kassotaki, Elissavet

    2014-04-01

    We estimate the nutrient budget in a temporary Mediterranean river basin. We use field monitoring and modelling tools to estimate nutrient sources and transfer in both high and low flow conditions. Inverse modelling by the help of PHREEQC model validated the hypothesis of a losing stream during the dry period. Soil and Water Assessment Tool model captured the water quality of the basin. The 'total daily maximum load' approach is used to estimate the nutrient flux status by flow class, indicating that almost 60% of the river network fails to meet nitrogen criteria and 50% phosphate criteria. We recommend that existing well-documented remediation measures such as reforestation of the riparian area or composting of food process biosolids should be implemented to achieve load reduction in close conjunction with social needs.

  8. Western Gas Sands Project. Quarterly Basin Activities Report

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, C H

    1979-01-31

    This report is a summation of 3 months' drilling and testing activities in the four primary WGSP study areas: Greater Green River Basin, Northern Great Plains Province, Piceance Basin, and Uinta Basin. The monitoring of basin activities is part of resource assessment. (DLC)

  9. Basin-scale simulation of current and potential climate changed hydrologic conditions in the Lake Michigan Basin, United States

    Science.gov (United States)

    Christiansen, Daniel E.; Walker, John F.; Hunt, Randall J.

    2014-01-01

    The Great Lakes Restoration Initiative (GLRI) is the largest public investment in the Great Lakes in two decades. A task force of 11 Federal agencies developed an action plan to implement the initiative. The U.S. Department of the Interior was one of the 11 agencies that entered into an interagency agreement with the U.S. Environmental Protection Agency as part of the GLRI to complete scientific projects throughout the Great Lakes basin. The U.S. Geological Survey, a bureau within the Department of the Interior, is involved in the GLRI to provide scientific support to management decisions as well as measure progress of the Great Lakes basin restoration efforts. This report presents basin-scale simulated current and forecast climatic and hydrologic conditions in the Lake Michigan Basin. The forecasts were obtained by constructing and calibrating a Precipitation-Runoff Modeling System (PRMS) model of the Lake Michigan Basin; the PRMS model was calibrated using the parameter estimation and uncertainty analysis (PEST) software suite. The calibrated model was used to evaluate potential responses to climate change by using four simulated carbon emission scenarios from eight general circulation models released by the World Climate Research Programme’s Coupled Model Intercomparison Project phase 3. Statistically downscaled datasets of these scenarios were used to project hydrologic response for the Lake Michigan Basin. In general, most of the observation sites in the Lake Michigan Basin indicated slight increases in annual streamflow in response to future climate change scenarios. Monthly streamflows indicated a general shift from the current (2014) winter-storage/snowmelt-pulse system to a system with a more equally distributed hydrograph throughout the year. Simulated soil moisture within the basin illustrates that conditions within the basin are also expected to change on a monthly timescale. One effect of increasing air temperature as a result of the changing

  10. In situ characterization of Hanford K Basins fuel

    Energy Technology Data Exchange (ETDEWEB)

    Pitner, A.L.

    1998-01-06

    Irradiated N Reactor uranium metal fuel is stored underwater in the Hanford K East and K West Basins. In K East Basin, fuel is stored in open canisters and defected fuel is free to react with the basin water. In K West Basin, the fuel is stored in sealed canisters filled with water containing a corrosion inhibitor (potassium nitrite). To gain a better understanding of the physical condition of the fuel in these basins, visual surveys using high resolution underwater cameras were conducted. The inspections included detailed lift and look examinations of a number of fuel assemblies from selected canisters in each basin. These examinations formed the bases for selecting specific fuel elements for laboratory testing and analyses as prescribed in the characterization plan for Hanford K Basin Spent Nuclear Fuel.

  11. Characteristic mega-basin water storage behavior using GRACE.

    Science.gov (United States)

    Reager, J T; Famiglietti, James S

    2013-06-01

    [1] A long-standing challenge for hydrologists has been a lack of observational data on global-scale basin hydrological behavior. With observations from NASA's Gravity Recovery and Climate Experiment (GRACE) mission, hydrologists are now able to study terrestrial water storage for large river basins (>200,000 km 2 ), with monthly time resolution. Here we provide results of a time series model of basin-averaged GRACE terrestrial water storage anomaly and Global Precipitation Climatology Project precipitation for the world's largest basins. We address the short (10 year) length of the GRACE record by adopting a parametric spectral method to calculate frequency-domain transfer functions of storage response to precipitation forcing and then generalize these transfer functions based on large-scale basin characteristics, such as percent forest cover and basin temperature. Among the parameters tested, results show that temperature, soil water-holding capacity, and percent forest cover are important controls on relative storage variability, while basin area and mean terrain slope are less important. The derived empirical relationships were accurate (0.54 ≤  E f  ≤ 0.84) in modeling global-scale water storage anomaly time series for the study basins using only precipitation, average basin temperature, and two land-surface variables, offering the potential for synthesis of basin storage time series beyond the GRACE observational period. Such an approach could be applied toward gap filling between current and future GRACE missions and for predicting basin storage given predictions of future precipitation.

  12. Strike-slip tectonics and Quaternary basin formation along the Vienna Basin fault system inferred from Bouguer gravity derivatives

    NARCIS (Netherlands)

    Salcher, B. C.; Meurers, B.; Smit, J.; Decker, K.; HöLzel, M.; Wagreich, M.

    2012-01-01

    The Vienna Basin at the transition between the Alpine and Carpathian belt hosts a number of large Pleistocene sub-basins forming along an active continental scale strike-slip fault (Vienna Basin strike-slip fault). We utilize first-order derivatives from industrial Bouguer gravity data to unravel

  13. IRBM for the Rio Conchos Basin as a Restoration and Conservation Tool

    Science.gov (United States)

    Barrios, E.; Rodriguez, J. A.; de La Maza, M.

    2007-12-01

    The Rio Conchos basin is the main water supply for the people of the State of Chihuahua and the middle and lower Rio Bravo in northern Mexico. Flowing for about 850 km from the highlands of the Sierra Tarahumara towards the wide valleys of the Chihuahuan Desert, the river presents recurrent periods of water stress and its basin of 6.7 million of hectares experiences a wide spectrum of problems such us long drought periods, water over allocation and extraction, water pollution, severe soil use changes. Besides, drastic soil moisture reduction is forecasted by effects of climate change. These natural and anthropological harmful situations impose a serious stress for this important and beautiful river and the rest of the basin hydrological resources. The WWF-Gonzalo Rio Arronte Alliance and its partners USAID, The Coca Cola Company and RICOH are implementing since 2004 an Integrated River Basin Management (IRBM) strategy to recover the natural integrity of the Rio Conchos in the form of environmental flow. The strategy includes the five basic working lines: i) development of river basin scientific knowledge, ii) strengthen of local institutional capacities, iii) development of demonstrative projects, iv) strengthen of indigenous communities, v) education and communication. Although the implementation of the IRBM program is expected to show main results until the year 2050, some interesting results have been obtained. The strategy has provided i) new basic knowledge about the basin dynamic events such as soil change use rates, baseline values of biological integrity, water economic values, among others; ii) strong program acceptance by government and main water users (farmers), and the integration of a working group formed by government, academia and NGO's; iii) local acceptance and understanding of benefits about basin management (soil recovery, reforestation, ecological sanitation) through demonstrative projects; iv) social organization; v) few advances in education

  14. A topological system for delineation and codification of the Earth's river basins

    Science.gov (United States)

    Verdin, K.L.; Verdin, J.P.

    1999-01-01

    A comprehensive reference system for the Earth's river basins is proposed as a support to fiver basin management, global change research, and the pursuit of sustainable development. A natural system for delineation and codification of basins is presented which is based upon topographic control and the topology of the fiver network. These characteristics make the system well suited for implementation and use with digital elevation models (DEMs) and geographic information systems. A demonstration of these traits is made with the 30-arcsecond GTOPO30 DEM for North America. The system has additional appeal owing to its economy of digits and the topological information that they carry. This is illustrated through presentation of comparisons with USGS hydrologic unit codes and demonstration of the use of code numbers to reveal dependence or independence of water use activities within a basin.

  15. A Water Resources Planning Tool for the Jordan River Basin

    Directory of Open Access Journals (Sweden)

    Christopher Bonzi

    2011-06-01

    Full Text Available The Jordan River basin is subject to extreme and increasing water scarcity. Management of transboundary water resources in the basin is closely intertwined with political conflicts in the region. We have jointly developed with stakeholders and experts from the riparian countries, a new dynamic consensus database and—supported by hydro-climatological model simulations and participatory scenario exercises in the GLOWA (Global Change and the Hydrological Cycle Jordan River project—a basin-wide Water Evaluation and Planning (WEAP tool, which will allow testing of various unilateral and multilateral adaptation options under climate and socio-economic change. We present its validation and initial (climate and socio-economic scenario analyses with this budget and allocation tool, and invite further adaptation and application of the tool for specific Integrated Water Resources Management (IWRM problems.

  16. Hydrosalinity studies of the Virgin River, Dixie Hot Springs, and Littlefield Springs, Utah, Arizona, and Nevada

    Science.gov (United States)

    Gerner, Steven J.; Thiros, Susan A.; Gerner, Steven J.; Thiros, Susan A.

    2014-01-01

    The Virgin River contributes a substantial amount of dissolved solids (salt) to the Colorado River at Lake Mead in the lower Colorado River Basin. Degradation of Colorado River water by the addition of dissolved solids from the Virgin River affects the suitability of the water for municipal, industrial, and agricultural use within the basin. Dixie Hot Springs in Utah are a major localized source of dissolved solids discharging to the Virgin River. The average measured discharge from Dixie Hot Springs during 2009–10 was 11.0 cubic feet per second (ft3/s), and the average dissolved-solids concentration was 9,220 milligrams per liter (mg/L). The average dissolved-solids load—a measurement that describes the mass of salt that is transported per unit of time—from Dixie Hot Springs during this period was 96,200 tons per year (ton/yr). Annual dissolved-solids loads were estimated at 13 monitoring sites in the Virgin River Basin from streamflow data and discrete measurements of dissolved-solids concentrations and (or) specific conductance. Eight of the sites had the data needed to estimate annual dissolved-solids loads for water years (WYs) 1999 through 2010. During 1999–2010, the smallest dissolved-solids loads in the Virgin River were upstream of Dixie Hot Springs (59,900 ton/yr, on average) and the largest loads were downstream of Littlefield Springs (298,200 ton/yr, on average). Annual dissolved-solids loads were smallest during 2002–03, which was a period of below normal precipitation. Annual dissolved-solids loads were largest during 2005—a year that included a winter rain storm that resulted in flooding throughout much of the Virgin River Basin. An average seepage loss of 26.7 ft3/s was calculated from analysis of monthly average streamflow from July 1998 to September 2010 in the Virgin River for the reach that extends from just upstream of the Utah/Arizona State line to just above the Virgin River Gorge Narrows. Seepage losses from three river reaches

  17. Klamath River Basin water-quality data

    Science.gov (United States)

    Smith, Cassandra D.; Rounds, Stewart A.; Orzol, Leonard L.; Sobieszczyk, Steven

    2018-05-29

    The Klamath River Basin stretches from the mountains and inland basins of south-central Oregon and northern California to the Pacific Ocean, spanning multiple climatic regions and encompassing a variety of ecosystems. Water quantity and water quality are important topics in the basin, because water is a critical resource for farming and municipal use, power generation, and for the support of wildlife, aquatic ecosystems, and endangered species. Upper Klamath Lake is the largest freshwater lake in Oregon (112 square miles) and is known for its seasonal algal blooms. The Klamath River has dams for hydropower and the upper basin requires irrigation water to support agriculture and grazing. Multiple species of endangered fish inhabit the rivers and lakes, and the marshes are key stops on the Pacific flyway for migrating birds. For these and other reasons, the water resources in this basin have been studied and monitored to support their management distribution.

  18. Movement of water infiltrated from a recharge basin to wells.

    Science.gov (United States)

    O'Leary, David R; Izbicki, John A; Moran, Jean E; Meeth, Tanya; Nakagawa, Brandon; Metzger, Loren; Bonds, Chris; Singleton, Michael J

    2012-01-01

    Local surface water and stormflow were infiltrated intermittently from a 40-ha basin between September 2003 and September 2007 to determine the feasibility of recharging alluvial aquifers pumped for public supply, near Stockton, California. Infiltration of water produced a pressure response that propagated through unconsolidated alluvial-fan deposits to 125 m below land surface (bls) in 5 d and through deeper, more consolidated alluvial deposits to 194 m bls in 25 d, resulting in increased water levels in nearby monitoring wells. The top of the saturated zone near the basin fluctuates seasonally from depths of about 15 to 20 m. Since the start of recharge, water infiltrated from the basin has reached depths as great as 165 m bls. On the basis of sulfur hexafluoride tracer test data, basin water moved downward through the saturated alluvial deposits until reaching more permeable zones about 110 m bls. Once reaching these permeable zones, water moved rapidly to nearby pumping wells at rates as high as 13 m/d. Flow to wells through highly permeable material was confirmed on the basis of flowmeter logging, and simulated numerically using a two-dimensional radial groundwater flow model. Arsenic concentrations increased slightly as a result of recharge from 2 to 6 µg/L immediately below the basin. Although few water-quality issues were identified during sample collection, high groundwater velocities and short travel times to nearby wells may have implications for groundwater management at this and at other sites in heterogeneous alluvial aquifers. Ground Water © 2011, National Ground Water Association. Published 2011. This article is a U.S. Government work and is in the public domain in the USA.

  19. Degradation and damages from utilizing ecosystem services in a river basin

    Science.gov (United States)

    Travis W. Warziniack

    2012-01-01

    We examine the tradeoffs between utilizing multiple ecosystem services in an economic model of the Lower Mississippi-Atchafalaya River Basin. We show how economic development in the basin degraded the ecosystem, but diversified the economy. A degraded ecosystem and more employment opportunities elsewhere reduced the region's reliance on agriculture and other...

  20. The role of Mesozoic sedimentary basin tapers on the formation of Cenozoic crustal shortening structures and foredeep in the western Sichuan Basin, China

    Science.gov (United States)

    Wang, M.

    2017-12-01

    The foreland basin records important clues of tectonic and sedimentary process of mountain-building, thus to explore its dynamic mechanism on the formation is an important issue of the mountain-basin interaction. The Longmen Shan fold-and-thrust belt and its adjacent Sichuan basin located in the eastern margin of Tibetan Plateau, are one of the most-concerned regions of studying modern mountain-building and seismic process, and are also a natural laboratory of studying the dynamics of the formation and development of foreland basin. However, it still need further explore on the mechanics of the development of the Cenozoic foreland basin and thrust-belts in the western Sichuan Basin. The Longmen Shan thrust belt has experienced multi-stages of tectonics evolution, foreland basin formation and topography growth since Late Triassic, and whether the early formed basin architecture and large Mesozoic sedimentary basin taper can influence the formation and development of the Cenozoic foreland basin and thrust belts? To solve these issues, this project aim to focus on the Cenozoic foreland basin and internal crustal shortening structures in the western Sichuan basin, on the basis of growth critical wedge taper theory. We will reconstruct the shape of multi-phases of sedimentary basin tapers, the temporal-spatial distribution of crustal shortening and thrusting sequences, and analyze the control mechanism of Mesozoic sedimentary basin taper on the formation of Cenozoic foreland basins, and final explore the interaction between the tectonics geomorphology, stress field and dynamic propagation of foreland basin.