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Site characterization plan: Yucca Mountain Site, Nevada Research and Development Area, Nevada: Volume 4, Part B: Chapter 8, Sections 8.0 through 8.3.1.4

Description: This site characterization plan (SCP) has been developed for the candidate repository site at Yucca Mountain in the State of Nevada. The SCP includes a description of the Yucca Mountain site (Chapters 1-5), a conceptual design for the repository (Chapter 6), a description of the packaging to be used for the waste to be emplaced in the repository (Chapter 7), and a description of the planned site characterization activities (Chapter 8). The schedules and milestones presented in Sections 8.3 and … more
Date: December 1, 1988
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Behavior of nuclear waste elements during hydrothermal alteration of glassy rhyolite in an active geothermal system: Yellowstone National Park, Wyoming

Description: The behavior of a group of nuclear waste elements (U, Th, Sr, Zr, Sb, Cs, Ba, and Sm) during hydrothermal alteration of glassy rhyolite is investigated through detailed geochemical analyses of whole rocks, glass and mineral separates, and thermal waters. Significant mobility of U, Sr, Sb, Cs, and Ba is found, and the role of sorption processes in their observed behavior is identified. Th, Zr, and Sm are relatively immobile, except on a microscopic scale. 9 references, 2 figures, 2 tables.
Date: December 31, 1984
Creator: Sturchio, N.C. & Seitz, M.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some geochemical considerations for a potential repository site in tuff at Yucca Mountain, Nevada

Description: The Nevada Nuclear Waste Storage Investigations, which is evaluating potential locations for a high-level waste repository at the Nevada Test Site and environs, is currently focusing its investigations on tuff, principally in Yucca Mountain, as a host rock. This paper discusses some of the geochemical investigations. Particular emphasis is placed on definition of some basic elements and necessary technical approaches for the geochemistry data acquisition and modeling program. Some site-specific… more
Date: December 1982
Creator: Erdal, B. R.; Bish, D. L.; Crowe, B. M.; Daniels, W. R.; Ogard, A. E.; Rundberg, R. S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of geochemical processes on the transport of contaminants in multicomponent systems: a modeling perspective

Description: An equilibrium geochemical transport model for multicomponent systems, TRANQL, was used to investigate the effects of geochemical processes on the transport of contaminants. TRANQL was used to investigate the sensitivity of cadmium transport to a range of initial condition, pH, complexing ligand concentrations, and concentrations of a simultaneously sorbing solute. Aqueous-phase complexation, dissociation of water, and sorption were the processes considered. First, the transport of an initial p… more
Date: December 31, 1985
Creator: Cederberg, Gail A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Using chloride to trace water movement in the unsaturated zone at Yucca Mountain

Description: The nonwelded Paintbrush Tuff (PTn) hydrogeologic unit is postulated as playing a critical role in the redistribution of moisture in the unsaturated zone at Yucca Mountain, Nevada. Fracture-dominated flow in the overlying low-permeability, highly fractured Tiva Canyon welded (TCw) unit is expected to transition to matrix-dominated flow in the high-permeability, comparatively unfractured PTn. The transition process from fracture to matrix flow in the PTn, as well as the transition from low to hi… more
Date: December 31, 1998
Creator: Fabryka-Martin, J.T.; Winters, S.T.; Wolfsberg, A.V.; Wolfsberg, L.E. & Roach, J.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Summary of micrographic analysis of fracture coating phases on drill cores from Pahute Mesa, Nevada Test Site. Revision 1

Description: The flow path between Pahute Mesa and the groundwater discharge area in Oasis Valley (approximately 18 miles to the southwest) is of concern due to the relatively short travel distance between a recharge area where underground nuclear testing has been conducted and the off-site water users. Groundwater flow and transport modeling by IT Corporation (IT) has shown rapid tritium transport in the volcanic rock aquifers along this flow path. The resultant estimates of rapid transport were based on w… more
Date: December 1, 1998
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sedimentary basin geochemistry and fluid/rock interactions workshop

Description: Fundamental research related to organic geochemistry, fluid-rock interactions, and the processes by which fluids migrate through basins has long been a part of the U.S. Department of Energy Geosciences program. Objectives of this program were to emphasize those principles and processes which would be applicable to a wide range of problems associated with petroleum discovery, occurrence and extraction, waste disposal of all kinds, and environmental management. To gain a better understanding of t… more
Date: December 31, 1991
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Geochemistry and migration of contaminants at the Weldon Spring chemical plant site, St. Charles County, Missouri, 1989--91

Description: Investigations were conducted by the US Geological Survey in cooperation with the US Department of Energy at the Weldon Spring chemical plant site to determine the geochemistry of the shallow aquifer and geochemical controls on the migration of uranium and other constituents from the raffinate (waste) pits. Water-quality analyses from monitoring wells at the site and vicinity property indicate that water in the shallow aquifer is a calcium magnesium bicarbonate type that is at equilibrium with … more
Date: December 31, 1993
Creator: Schumacher, J.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CO{sub 2} flux measurements across portions of the Dixie Valley geothermal system, Nevada

Description: A map of the CO{sub 2} flux across a newly formed area of plant kill in the NW part of the Dixie Valley geothermal system was constructed to monitor potential growth of a fumarole field. Flux measurements were recorded using a LI-COR infrared analyzer. Sample locations were restricted to areas within and near the dead zone. The data delineate two areas of high CO{sub 2} flux in different topographic settings. Older fumaroles along the Stillwater range front produce large volumes of CO{sub 2} at… more
Date: December 31, 1998
Creator: Bergfeld, Deborah; Goff, Fraser; Janik, Cathy J. & Johnson, Stuart D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beryllium-10 in the Taylor Dome ice core: Applications to Antarctic glaciology and paleoclimatology

Description: An ice core was drilled at Taylor dome, East Antarctica, reaching to bedrock at 554 meters. Oxygen-isotope measurements reveal climatic fluctuations through the last interglacial period. To facilitate comparison of the Taylor Dome paleoclimate record with geologic data and results from other deep ice cores, several glaciological issues need to be addressed. In particular, accumulation data are necessary as input for numerical ice-flow-models, for determining the flux of chemical constituents fr… more
Date: December 31, 1996
Creator: Steig, E. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Field-based tests of geochemical modeling codes: New Zealand hydrothermal systems

Description: Hydrothermal systems in the Taupo Volcanic Zone, North Island, New Zealand are being used as field-based modeling exercises for the EQ3/6 geochemical modeling code package. Comparisons of the observed state and evolution of the hydrothermal systems with predictions of fluid-solid equilibria made using geochemical modeling codes will determine how the codes can be used to predict the chemical and mineralogical response of the environment to nuclear waste emplacement. Field-based exercises allow … more
Date: December 1, 1993
Creator: Bruton, C. J.; Glassley, W. E. & Bourcier, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Groundwater monitoring program evaluation For A/M Area, Savannah River Site

Description: This investigation was undertaken with the primary purpose of assessing the groundwater monitoring program within the A/M Area to identify ways in which the monitoring program could be improved. The task was difficult due to the large number of wells located within the A/M Area and the huge database of analytical data. It was recognized early in this investigation that one of the key tasks was to develop a way to gain access to the groundwater databases so that recommendations could be made. To… more
Date: December 1, 1996
Creator: Hiergesell, R.A. & Bollinger, J.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final report on feasibility of real-time geochemical analysis at Yucca Mountain, Nevada, using LIBS technology

Description: Laser-induced breakdown spectroscopy (LIBS) is an analytic method whereby an intense laser pulse is used to vaporize and excite a small volume of material into atomic emission. Calibrated spectral analysis of the laser spark light provides detection and quantification of the elemental composition of the target material. We performed laboratory and field tests to assess the feasibility of developing field-portable LIBS-based instruments for real-time analyses of Yucca Mountain rocks in conjuncti… more
Date: December 1, 1996
Creator: Blacic, J. D.; Pettit, D. R. & Cremers, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geochemical and Pb, Sr, and O isotopic study of the Tiva Canyon Tuff and Topopah Spring Tuff, Yucca Mountain, Nye County, Nevada

Description: Yucca Mountain is currently being studied as a potential site for an underground repository for high-level radioactive waste. One aspect of the site characterization studies is an evaluation o the resource potential at Yucca Mountain. Geochemical and isotopic signatures of past alteration of the welded tuffs that underlie Yucca Mountain provide a means of assessing the probability of hydrothermal ore deposits being present within Yucca Mountain. In this preliminary report, geochemical and isoto… more
Date: December 31, 1995
Creator: Neymark, L.A.; Marshall, B.D.; Kwak, L.M.; Futa, Kiyoto & Mahan, S.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The microbial methane cycle in subsurface sediments. Final project report, July 1, 1993--August 31, 1997

Description: The objectives of this study were to determine the factors controlling microbial activity and survival in the subsurface and, specifically, to determine whether microbial communities in aquitards and in aquifer microenvironments provide electron donors and/or acceptors that enhance microbial survival in aquifers. Although the original objectives were to focus on methane cycling, the authors pursued an opportunity to study sulfur cycling in aquifer systems, a process of much greater importance i… more
Date: December 31, 1997
Creator: Grossman, E. L.; Ammerman, J. W. & Suflita, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Site characterization plan: Yucca Mountain Site, Nevada Research and Development Area, Nevada: Volume 2, Part A: Chapters 3, 4, and 5

Description: This site characterization plan (SCP) has been developed for the candidate repository site at Yucca Mountain in the State of Nevada. The SCP includes a description of the Yucca Mountain site (Chapters 1--5), a conceptual design for the repository (Chapter 6), a description of the packaging to be used for the waste to be emplaced in the repository (Chapter 7), and a description of the planned site characterization activities (Chapter 8). The schedules and milestones presented in Sections 8.3 and… more
Date: December 1, 1988
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Summary report on the geochemistry of Yucca Mountain and environs

Description: This report gives a detailed description of work at Los Alamos that will help resolve geochemical issues pertinent to siting a high-level nuclear waste repository in tuff at Yucca Mountain, Nevada. It is necessary to understand the properties and setting of the host tuff because this rock provides the first natural barrier to migration of waste elements from a repository. The geochemistry of tuff is being investigated with particular emphasis on retardation processes. This report addresses the … more
Date: December 1, 1982
Creator: Daniels, W.R.; Wolfsberg, K. & Rundberg, R.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Contracts for field projects and supporting research on enhanced oil recovery. Quarterly progress review No. 85, October 1, 1995--December 31, 1995

Description: This documents presents progress on enhanced oil recovery programs and reservoir characterization programs. Information is presented on contract numbers, awards, investigators, and project managers.
Date: December 1, 1996
Creator: Godley, P. & Waisley, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Geochemical Earth Reference Model (GERM)

Description: The Geochemical Earth Reference Model (GERM) initiative is a grass- roots effort with the goal of establishing a community consensus on a chemical characterization of the Earth, its major reservoirs, and the fluxes between them. Long term goal of GERM is a chemical reservoir characterization analogous to the geophysical effort of the Preliminary Reference Earth Model (PREM). Chemical fluxes between reservoirs are included into GERM to illuminate the long-term chemical evolution of the Earth and… more
Date: December 1, 1996
Creator: Staudigel, H.; Albarede, F.; Shaw, H.; McDonough, B. & White, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Release of oxide-bound toxic metals by naturally-occurring and contaminant-derived organic compounds: The role of complexant, reductant, and adsorptive characteristics. Final report, July 1, 1994--June 31, 1997

Description: Natural organic compounds and contaminant-derived organic compounds can substantially alter the speciation and geochemical behavior of contaminant metals in subsurface environments. The goal, as part of the Co-Contaminant Subprogram, was to: (1) develop analytical methods for identifying and quantifying organic compounds affecting toxic metal speciation; (2) evaluate their reductant, complexant, and adsorptive characteristics of organic compounds with regards to important contaminant metals; (3… more
Date: December 31, 1997
Creator: Stone, A. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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EQ3/6: status and applications

Description: EQ3/6 is a set of related computer codes and data files for use in geochemical modeling of aqueous systems. The EQ3/6 package centers around two large computer codes, EQ3NR and EQ6, which are supported by a common thermodynamic data base. EQ3NR is a speciation-solubility code, whose function is to compute a model of the state of an aqueous solution. This code is very flexible in terms of the input that it will accept. EQ6 is a reaction-path code, which calculates models of changes in aqueous sy… more
Date: December 1, 1984
Creator: Wolery, T. J.; Isherwood, D. J.; Jackson, K. J.; Delany, J. M. & Puigdomenech, I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluation of DOE Radionuclide Solubility Data and Selected Retardation Parameters: Description of Calculational and Confirmatory Experimental Activities

Description: An experimentally oriented program has been initiated to support the NRC analysis and licensing activities related to high-level nuclear waste repositories. The program will allow the NRC to independently confirm key geochemical values used in the site performance assessments submitted by the DOE candidate repository site projects. Key radionuclide retardation factor values, particularly radionuclide solubility and sorption values under site specific geochemical conditions, are being confirmed.… more
Date: December 31, 1983
Creator: Kelmers, A. D.; Clark, R. J.; Cutshall, N. H.; Johnson, J. S. & Kessler, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preliminary geochemical/geophysical model of Yucca Mountain

Description: A comprehensive geochemical/geophysical model incorporates the current and relevant stratigraphic, petrologic, hydrogeologic, geochemical, and material data associated with a candidate repository at Yucca Mountain, Nevada. A geochemical/geophysical model will provide support and confidence to the Systems Performance calculations, determine whether the data collected as part of the site characterization provide the information needed by the design and performance assessment task, and provide the… more
Date: December 31, 1987
Creator: Greenwade, L.E. & Cederberg, Gail A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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