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Batch sorption results for neptunium transport through Yucca Mountain tuffs. Yucca Mountain Site Characterization Program milestone 3349 (open access)

Batch sorption results for neptunium transport through Yucca Mountain tuffs. Yucca Mountain Site Characterization Program milestone 3349

We studied the sorption of neptunium onto tuffs characteristic of the proposed nuclear waste repository at Yucca Mountain, Nevada. The neptunium was in the Np(V) oxidation state under oxidizing conditions in groundwaters from two wells located close to the repository site (J-13 and UE-25 p No.1). We used devitrified, vitric, zeolitic (with emphasis on clinoptilolite-rich samples), and calcite-rich tuffs characteristic of the geology of the site. Neptunium sorbed well onto calcite and calcite-rich tuffs, indicating that a significant amount of neptunium retardation can be expected under fractured-flow scenarios because of calcite coating of the fractures. Neptunium sorption onto clinoptilolite-rich zeolitic tuffs in J-13 well water (pH from 7 to 8.5) was moderate, increased with decreasing pH, and correlated to surface area and amount of clinoptilolite. Neptunium sorbed poorly onto zeolitic tuffs from UE-25 p No.1 groundwater (pH from 7 to 9) and onto devitrified and vitric tuffs from J-13 and UE-25 p No.1 waters (pH from 7 to 9). Iron oxides appeared to be passivated in tuffs, not seeming to contribute to the observed neptunium sorption, even though neptunium sorption onto synthetic iron oxide is significant.
Date: September 1, 1996
Creator: Triay, I. R.; Cotter, C. R.; Huddleston, M. H. & Leonard, D. E.
Object Type: Report
System: The UNT Digital Library
Water levels in the Yucca Mountain area, Nevada, 1995 (open access)

Water levels in the Yucca Mountain area, Nevada, 1995

Water levels were monitored in 28 wells in the Yucca Mountain area, Nevada, during 1995. Seventeen wells representing 18 depth intervals were monitored periodically, generally on a monthly basis, 2 wells representing 3 depth intervals were monitored hourly, and 9 wells representing 15 depth intervals were monitored both periodically and hourly. All wells monitor water levels in Tertiary volcanic rocks except one that monitors water levels in Paleozoic carbonate rocks. Water levels were measured using calibrated steel tapes, a multiconductor cable unit, and/or pressure transducers. Mean water-level altitudes in the Tertiary volcanic rocks ranged from about 728 to about 1,034 meters above sea level during 1995. The mean water-level altitude in the well monitoring the Paleozoic carbonate rocks was about 753 meters above sea level during 1995. Mean water level altitudes were only an average of about 0.01 meters higher than 1994 mean water level altitudes. A single-well aquifer test was conducted on well UE-25 WT{number_sign}12 during August and September 1995. Well USW 0-2 was also pumped during October and November 1995, in preparation for single-well aquifer test at that well. All data were acquired in accordance with a quality-assurance program to support the reliability of the data.
Date: September 1, 1998
Creator: Graves, R. P. & Goemaat, R. L.
Object Type: Report
System: The UNT Digital Library
SYSTHESIS OF VOLCANISM STUDIES FOR THE YUCCA MOUNTAIN SITE CHARACTERIZATION PROJECT (open access)

SYSTHESIS OF VOLCANISM STUDIES FOR THE YUCCA MOUNTAIN SITE CHARACTERIZATION PROJECT

This report synthesizes the results of volcanism studies conducted by scientists at the Los Alamos National Laboratory and collaborating institutions on behalf of the Department of Energy's Yucca Mountain Project. Chapter 1 introduces the volcanism issue for the Yucca Mountain site and provides the reader with an overview of the organization, content, and significant conclusions of this report. The hazard of future basaltic volcanism is the primary topic of concern including both events that intersect a potential repository and events that occur near or within the waste isolation system of a repository. Future volcanic events cannot be predicted with certainty but instead are estimated using formal methods of probabilistic volcanic hazard assessment (PVHA). Chapter 2 describes the volcanic history of the Yucca Mountain region (YMR) and emphasizes the Pliocene and Quaternary volcanic record, the interval of primary concern for volcanic risk assessment. The distribution, eruptive history, and geochronology of Plio-Quaternary basalt centers are described by individual center emphasizing the younger postcaldera basalt (<5 Ma). The Lathrop Wells volcanic center is described in detail because it is the youngest basalt center in the YMR. The age of the Lathrop Wells center is now confidently determined to be about 75 thousand years …
Date: September 23, 1997
Creator: FV PERRY, GA CROWE, GA VALENTINE AND LM BOWKER
Object Type: Report
System: The UNT Digital Library
Geology of the USW SD-7 drill hole Yucca Mountain, Nevada (open access)

Geology of the USW SD-7 drill hole Yucca Mountain, Nevada

The USW SD-7 drill hole is one of several holes drilled under Site Characterization Plan Study 8.3.1.4.3.1, also known as the Systematic Drilling Program, as part of the U.S. Department of Energy characterization program at Yucca Mountain, Nevada. The Yucca Mountain site has been proposed as the potential location of a repository for high-level nuclear waste. The SD-7 drill hole is located near the southern end of the potential repository area and immediately to the west of the Main Test Level drift of the Exploratory Studies Facility. The hole is not far from the junction of the Main Test Level drift and the proposed South Ramp decline. Drill hole USW SD-7 is 2675.1 ft (815.3 m) deep, and the core recovered nearly complete sections of ash-flow tuffs belonging to the lower half of the Tiva Canyon Tuff, the Pah Canyon Tuff, and the Topopah Spring Tuff, all of which are part of the Miocene Paintbrush Group. Core was recovered from much of the underlying Calico Hills Formation, and core was virtually continuous in the Prow Pass Tuff and the Bullfrog Tuff. The SD-7 drill hole penetrated the top several tens of feet into the Tram Tuff, which underlies the Prow …
Date: September 1, 1996
Creator: Rautman, C.A. & Engstrom, D.A.
Object Type: Report
System: The UNT Digital Library
Yucca Mountain socioeconomic project report on the 1987 risk perception telephone surveys (open access)

Yucca Mountain socioeconomic project report on the 1987 risk perception telephone surveys

The measurement of the risk-related impacts from the siting of a high-level nuclear waste (HLNW) repository represents a new and important addition to conventional socioeconomic impact studies. In particular, the driving forces behind these impacts are the risks people perceive to be associated with the repository. Measuring the risk impacts requires a complementary set of approaches, of which, risk surveys are the cornerstone.a The purpose of these surveys is to provide scientifically defensible measures of the risk-related impacts. The risk surveys follow directly from a conceptual framework of how the HLNW repository affects peoples` perceptions and, ultimately, their behaviors. These surveys describe and measure: Characteristics of individuals, Risks people perceive from the HLNW repository, Views, or mind sets, they form about the HLNW repository, Changes in behaviors--e.g., changes in retirement decisions or industrial relocations--induced by the location of the repository, and Changes in well-being of Nevada citizens, if the repository were located at Yucca Mountain.
Date: September 1, 1987
Creator: Kunreuther, H.; Slovic, P.; Nigg, J. & Desvousges, W. H.
Object Type: Report
System: The UNT Digital Library
Phase I Flow and Transport Model Document for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada National Security Site, Nye County, Nevada, Revision 1 with ROTC 1 (open access)

Phase I Flow and Transport Model Document for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada National Security Site, Nye County, Nevada, Revision 1 with ROTC 1

The Underground Test Area (UGTA) Corrective Action Unit (CAU) 97, Yucca Flat/Climax Mine, in the northeast part of the Nevada National Security Site (NNSS) requires environmental corrective action activities to assess contamination resulting from underground nuclear testing. These activities are necessary to comply with the UGTA corrective action strategy (referred to as the UGTA strategy). The corrective action investigation phase of the UGTA strategy requires the development of groundwater flow and contaminant transport models whose purpose is to identify the lateral and vertical extent of contaminant migration over the next 1,000 years. In particular, the goal is to calculate the contaminant boundary, which is defined as a probabilistic model-forecast perimeter and a lower hydrostratigraphic unit (HSU) boundary that delineate the possible extent of radionuclide-contaminated groundwater from underground nuclear testing. Because of structural uncertainty in the contaminant boundary, a range of potential contaminant boundaries was forecast, resulting in an ensemble of contaminant boundaries. The contaminant boundary extent is determined by the volume of groundwater that has at least a 5 percent chance of exceeding the radiological standards of the Safe Drinking Water Act (SDWA) (CFR, 2012).
Date: September 1, 2013
Creator: Andrews, Robert
Object Type: Report
System: The UNT Digital Library
Technical data base quarterly report, April--June 1992; Yucca Mountain Site Characterization Project (open access)

Technical data base quarterly report, April--June 1992; Yucca Mountain Site Characterization Project

The acquisition and development of technical data are activities that provide the information base from which the Yucca mountain Site will be characterized and may P-ventually be licensed as a high-level waste repository. The Project Technical Data Base (TDB) is the repository for the regional and site-specific technical data required in intermediate and license application analyses and models. The TDB Quarterly Report provides the mechanism for identifying technical data currently available from the Project TDB. Due to the variety of scientific information generated by YMP activities, the Project TDB consists of three components, each designed to store specific types of data. The Site and Engineering Properties Data Base (SEPDB) maintains technical data best stored in a tabular format. The Geographic Nodal Information Study and Evaluation System (GENISES), which is the Geographic Information System (GIS) component of the Project TDB, maintains spatial or map-like data. The Geologic and Engineering Materials Bibliography of Chemical Species (GEMBOCHS) data base maintains thermodynamic/geochemical data needed to support geochemical reaction models involving the waste package and repository geochemical environment. Each of these data bases are addressed independently within the TDB Quarterly Report.
Date: September 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Uncertainty and Sensitivity of Contaminant Travel Times from the Upgradient Nevada Test Site to the Yucca Mountain Area (open access)

Uncertainty and Sensitivity of Contaminant Travel Times from the Upgradient Nevada Test Site to the Yucca Mountain Area

Yucca Mountain (YM), Nevada, has been proposed by the U.S. Department of Energy as the nation’s first permanent geologic repository for spent nuclear fuel and highlevel radioactive waste. In this study, the potential for groundwater advective pathways from underground nuclear testing areas on the Nevada Test Site (NTS) to intercept the subsurface of the proposed land withdrawal area for the repository is investigated. The timeframe for advective travel and its uncertainty for possible radionuclide movement along these flow pathways is estimated as a result of effective-porosity value uncertainty for the hydrogeologic units (HGUs) along the flow paths. Furthermore, sensitivity analysis is conducted to determine the most influential HGUs on the advective radionuclide travel times from the NTS to the YM area. Groundwater pathways are obtained using the particle tracking package MODPATH and flow results from the Death Valley regional groundwater flow system (DVRFS) model developed by the U.S. Geological Survey (USGS). Effectiveporosity values for HGUs along these pathways are one of several parameters that determine possible radionuclide travel times between the NTS and proposed YM withdrawal areas. Values and uncertainties of HGU porosities are quantified through evaluation of existing site effective-porosity data and expert professional judgment and are incorporated in …
Date: September 10, 2009
Creator: Zhu, J.; Pohlmann, K.; Chapman, J.; Russell, C.; Carroll, R.W.H. & Shafer, D.
Object Type: Report
System: The UNT Digital Library
MILESTONE SP25BM3: THE SITE-SCALE UNSATURATED ZONE TRANSPORT MODEL OF YUCCA MOUNTAIN (open access)

MILESTONE SP25BM3: THE SITE-SCALE UNSATURATED ZONE TRANSPORT MODEL OF YUCCA MOUNTAIN

None
Date: September 29, 1997
Creator: BA ROBINSON, AV WOFSBERG AND HS VISWANATHAN
Object Type: Report
System: The UNT Digital Library
Selected hydrologic data from Fortymile Wash in the Yucca Mountain area, Nevada, water years 1993--94 (open access)

Selected hydrologic data from Fortymile Wash in the Yucca Mountain area, Nevada, water years 1993--94

The Yucca Mountain area is being evaluated by the US Department of Energy for its suitability to store high-level nuclear waste in a mined, underground repository. Hydrologic data are being collected by the US Geological Survey throughout a 150 Km{sup 2} study area about 15- Km northwest of Las Vegas in southern Nevada for site characterization studies. Ongoing hydrologic studies are investigating atmospheric precipitation, stream-flow, movement of water through the unsaturated zone, movement of water through the saturated zone, and paleohydrology. This study at Fortymile Wash involves some components of each of these studies. Fortymile Wash is an ephemeral stream near Yucca Mountain with tributaries draining the east side of Yucca Mountain and then forming a distributary system in the Amargosa Desert. An objective of the study is to determine the amount of recharge from Fortymile Wash to the ground-water flow system that has been proposed. Understanding the ground-water flow system is important because it is a possible mechanism for radionuclide migration from the repository to the accessible environment. An adequate understanding of the ground-water flow system is necessary for an evaluation of the safety issues involved in siting the potential repository.
Date: September 1, 1996
Creator: Savard, C.S.
Object Type: Report
System: The UNT Digital Library
Near-surface velocity modeling at Yucca Mountain using borehole and surface records from underground nuclear explosions (open access)

Near-surface velocity modeling at Yucca Mountain using borehole and surface records from underground nuclear explosions

The Department of Energy is investigating Yucca Mountain, Nevada as a potential site for commercial radioactive waste disposal in a mined geologic repository. One critical aspect of site suitability is the tectonic stability of the repository site. The levels of risk from both actual fault displacements in the repository block and ground shaking from nearby earthquakes are being examined. In particular, it is necessary to determine the expected level of ground shaking at the repository depth for large seismic sources such as nearby large earthquakes or underground nuclear explosions (UNEs). Earthquakes are expected to cause the largest ground motions at the site, however, only underground nuclear explosion data have been obtained at the repository depth level (about 350m below the ground level) to date. In this study we investigate ground motion from Nevada Test Site underground nuclear explosions recorded at Yucca Mountain to establish a compressional velocity model for the uppermost 350m of the mountain. This model is useful for prediction of repository-level ground motions for potential large nearby earthquakes.
Date: September 1, 1996
Creator: Durrani, B.A. & Walck, M.C.
Object Type: Report
System: The UNT Digital Library
Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste (Volume 1) Introduction (open access)

Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste (Volume 1) Introduction

Yucca Mountain in Nevada represents the proposed solution to what has been a lengthy national effort to dispose of high-level radioactive waste, waste which must be isolated from the biosphere for tens of thousands of years. This chapter reviews the background of that national effort and includes some discussion of international work in order to provide a more complete framework for the problem of waste disposal. Other chapters provide the regional geologic setting, the geology of the Yucca Mountain site, the tectonics, and climate (past, present, and future). These last two chapters are integral to prediction of long-term waste isolation.
Date: September 25, 2006
Creator: Levich, R.A. & Stuckless, J.S.
Object Type: Article
System: The UNT Digital Library
Risk assessment for the Yucca Mountain high-level nuclear waste repository site: Estimation of volcanic disruption. Final report (open access)

Risk assessment for the Yucca Mountain high-level nuclear waste repository site: Estimation of volcanic disruption. Final report

In this article, we model the volcanism near the proposed nuclear waste repository at Yucca Mountain, Nevada, U.S.A. by estimating the instantaneous recurrence rate using a nonhomogeneous Poisson process with Weibull intensity and by using a homogeneous Poisson process to predict future eruptions. We then quantify the probability that any single eruption is disruptive in terms of a (prior) probability distribution, since not every eruption would result in disruption of the repository. Bayesian analysis is performed to evaluate the volcanic risk. Based on the Quaternary data, a 90% confidence interval for the instantaneous recurrence rate near the Yucca Mountain site is (1.85 x 10{sup -6}/yr, 1.26 x 10{sup -5}/yr). Also, using these confidence bounds, the corresponding 90% confidence interval for the risk (probability of at least one disruptive eruption) for an isolation time of 10{sup 4} years is (1.0 x 10{sup -3}, 6.7 x 10{sup -3}), if it is assumed that the intensity remains constant during the projected time frame.
Date: September 30, 1992
Creator: Ho, Chih-Hsiang
Object Type: Report
System: The UNT Digital Library
Study plan for water movement test: Site Characterization Plan Study 8.3.1.2.2.2 (open access)

Study plan for water movement test: Site Characterization Plan Study 8.3.1.2.2.2

The water movement tracer test is designed to produce information derived from isotopic measurements of soil and tuff samples collected from Yucca Mountain that is pertinent for assessing the performance of a nuclear waste repository. Measurements of chlorine isotropic distributions will help characterize the percolation of precipitation into the unsaturated zone. The {sup 36}Cl in the unsaturated zone occurs from atmospheric fallout of {sup 36}Cl produced by cosmic-ray secondaries reacting with {sup 40}Ar and, to a lesser extent, with {sup 36}Ar. It also occurs as global fallout from high-yield nuclear weapons tests conducted at the Pacific Proving Grounds between 1952 and 1962. When chloride ions at the surface are washed underground by precipitation, the radioactive decay of the {sup 36}Cl in the chloride can be used to time the rate of water movement. The {sup 36}l half-life of 301,000 yr permits the detection of water movement in the range of approximately 50,000 to 2 million years. These data are part of the input for developing numerical models of ground water flow at this site. 5 refs., 4 figs., 4 tabs.
Date: September 1989
Creator: Norris, A. E.
Object Type: Report
System: The UNT Digital Library
A structural model analysis of public opposition to a high-level radioactive waste facility (open access)

A structural model analysis of public opposition to a high-level radioactive waste facility

Studies show that most Nevada residents and almost all state officials oppose the proposed high-level radioactive waste repository project at Yucca Mountain. Surveys of the public show that individual citizens view the Yucca Mountain repository as having high risk; nuclear experts, in contrast, believe the risks are very low. Policy analysts have suggested that public risk perceptions may be reduced by better program management, increased trust in the federal government, and increased economic benefits for accepting a repository. The model developed in this study is designed to examine the relationship between public perceptions of risk, trust in risk management, and potential economic impacts of the current repository program using a confirmatory multivariate method known as covariance structure analysis. The results indicate that perceptions of potential economic gains have little relationship to opposition to the repository. On the other hand, risk perceptions and the level of trust in repository management are closely related to each other and to opposition. The impacts of risk perception and trust in management on opposition to the repository result from a combination of their direct influences as well as their indirect influences operating through perceptions that the repository would have serious negative impacts on the state`s …
Date: September 1, 1991
Creator: Flynn, James; Mertz, C. K.; Slovic, Paul & Burns, Williams
Object Type: Report
System: The UNT Digital Library
The Nevada railroad system: Physical, operational, and accident characteristics (open access)

The Nevada railroad system: Physical, operational, and accident characteristics

This report provides a description of the operational and physical characteristics of the Nevada railroad system. To understand the dynamics of the rail system, one must consider the system`s physical characteristics, routing, uses, interactions with other systems, and unique operational characteristics, if any. This report is presented in two parts. The first part is a narrative description of all mainlines and major branchlines of the Nevada railroad system. Each Nevada rail route is described, including the route`s physical characteristics, traffic type and volume, track conditions, and history. The second part of this study provides a more detailed analysis of Nevada railroad accident characteristics than was presented in the Preliminary Nevada Transportation Accident Characterization Study (DOE, 1990).
Date: September 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Well ER-6-1 Tracer Test Analysis: Yucca Flat, Nevada Test Site, Nye County, Nevada, Rev. No.: 0 (open access)

Well ER-6-1 Tracer Test Analysis: Yucca Flat, Nevada Test Site, Nye County, Nevada, Rev. No.: 0

The ER-6-1 multiple-well aquifer test-tracer test (MWAT-TT) investigated groundwater flow and transport processes relevant to the transport of radionuclides from sources on the Nevada Test Site (NTS) through the lower carbonate aquifer (LCA) hydrostratigraphic unit (HSU). The LCA, which is present beneath much of the NTS, is the principal aquifer for much of southern Nevada. This aquifer consists mostly of limestone and dolomite, and is pervasively fractured. Groundwater flow in this aquifer is primarily in the fractures, and the hydraulic properties are primarily related to fracture frequency and fracture characteristics (e.g., mineral coatings, aperture, connectivity). The objective of the multiple-well aquifer test (MWAT) was to determine flow and hydraulic characteristics for the LCA in Yucca Flat. The data were used to derive representative flow model and parameter values for the LCA. The items of specific interest are: Hydraulic conductivity; Storage parameters; Dual-porosity behavior; and Fracture flow characteristics. The objective of the tracer transport experiment was to evaluate the transport properties and processes of the LCA and to derive representative transport parameter values for the LCA. The properties of specific interest are: Effective porosity; Matrix diffusion; Longitudinal dispersivity; Adsorption characteristics; and Colloid transport characteristics. These properties substantially control the rate of …
Date: September 1, 2006
Creator: Ruskauff, Greg
Object Type: Report
System: The UNT Digital Library
Stress corrosion cracking of candidate materials for nuclear waste containers (open access)

Stress corrosion cracking of candidate materials for nuclear waste containers

Types 304L and 316L stainless steel (SS), Incoloy 825, Cu, Cu-30%Ni, and Cu-7%Al have been selected as candidate materials for the containment of high-level nuclear waste at the proposed Yucca Mountain Site in Nevada. The susceptibility of these materials to stress corrosion cracking has been investigated by slow-strain-rate tests (SSRTs) in water which simulates that from well J-13 (J-13 water) and is representative of the groundwater present at the Yucca Mountain site. The SSRTs were performed on specimens exposed to simulated J-13 water at 93{degree}C and at a strain rate 10{sup {minus}7} s{sup {minus}1} under crevice conditions and at a strain rate of 10{sup {minus}8} s{sup {minus}1} under both crevice and noncrevice conditions. All the tests were interrupted after nominal elongation strains of 1--4%. Examination by scanning electron microscopy showed some crack initiation in virtually all specimens. Optical microscopy of metallographically prepared transverse sections of Type 304L SS suggests that the crack depths are small (<10 {mu}m). Preliminary results suggest that a lower strain rate increases the severity of cracking of Types 304L and 316L SS, Incoloy 825, and Cu but has virtually no effect on Cu-30%Ni and Cu-7%Al. Differences in susceptibility to cracking were evaluated in terms of a …
Date: September 1, 1989
Creator: Maiya, P.S.; Shack, W.J. & Kassner, T.F.
Object Type: Article
System: The UNT Digital Library
Repository thermal response: A preliminary evaluation of the effects of modeled waste stream resolution (open access)

Repository thermal response: A preliminary evaluation of the effects of modeled waste stream resolution

One of the primary factors that influences our predictions of host-rock thermal response within a high level waste repository is how the waste stream`s represented in the models. In the context of thermal modeling, waste stream refers to an itemized listing of the type (pressurized-water or boiling-water reactor), age, burnup, and enrichment of the spent nuclear fuel assemblies entering the repository over the 25-year emplacement phase. The effect of package-by-package variations in spent fuel characteristics on predicted repository thermal response is the focus of this report. A three-year portion of the emplacement period was modeled using three approaches to waste stream resolution. The first assumes that each package type emplaced in a given year is adequately represented by average characteristics. For comparison, two models that explicitly account for each waste package`s individual characteristics were run; the first assuming a random selection of packages and the second an ordered approach aimed at locating the higher power output packages toward the center of the emplacement area. Results indicate that the explicit representation of packages results in hot and cold spots that could have performance assessment and design implications. Furthermore, questions are raised regarding the representativeness of average characteristics with respect to integrated …
Date: September 1, 1995
Creator: Ryder, E.E. & Dunn, E.
Object Type: Report
System: The UNT Digital Library
Geophysical tomography for imaging water movement in welded tuff (open access)

Geophysical tomography for imaging water movement in welded tuff

Alterant tomography has been evaluated for its ability to delineate in-situ water flow paths in a fractured welded-tuff rock mass. The evaluation involved a field experiment in which tomographs of electromagnetic attenuation factor (or attenuation rate) at 300 MHz were made before, during, and after the introduction to the rock of two different water-based tracers: a plain water and dye solution, and salt water and dye. Alterant tomographs were constructed by subtracting, cell by cell, the attenuation factors derived from measurements before each tracer was added to the rock mass from the attenuation factors derived after each tracer was added. The alterant tomographs were compared with other evidence of water movement in the rock: borescope logs of fractures, and post experiment cores used to locate the dye tracer on the fractured surfaces. These comparisons indicate that alterant tomography is suitable for mapping water flow through fractures and that it may be useful in inferring which of the fractures are hydrologically connected in the image plane. The technique appears to be sensitive enough to delineate flow through a single fracture and to define fractures with a spatial resolution of about 10 cm on an imaging scale of a few meters. 9 …
Date: September 1, 1986
Creator: Daily, W.D. & Ramirez, A.L.
Object Type: Article
System: The UNT Digital Library
Hydrothermal interaction of solid wafers of Topopah Spring Tuff with J-13 water and distilled water at 90, 150, and 250{sup 0}C, using Dickson-type, gold-bag rocking autoclaves (open access)

Hydrothermal interaction of solid wafers of Topopah Spring Tuff with J-13 water and distilled water at 90, 150, and 250{sup 0}C, using Dickson-type, gold-bag rocking autoclaves

The Nevada Nuclear Waste Storage Investigations Project has conducted experiments to study the hydrothermal interaction of rock and water representative of a potential high-level waste repository at Yucca Mountain, Nevada. The results of these experiments help define the near-field repository environment during and shortly after the thermal period that results from the emplacement of nuclear waste. When considered in conjunction with results contained in companion reports, these results can be used to assess our ability to accelerate tests using the surface area/volume parameter and/or temperature. These rock-water interaction experiments were conducted with solid polished wafers cut from both drillcore and outcrop samples of Topopah tuff, using both a natural ground water and distilled water as the reacting fluid. Pre- and post-test characterization of the reacting materials was extensive. Post-test identification and chemical analysis of secondary phases resulting from the hydrothermal interactions were aided by using monoliths of tuff rather than crushed material. All experiments were run in Dickson-type, gold-bag rocking autoclaves that were periodically sampled at in situ conditions. A total of nine short-term (up to 66-day) experiments were run in this series; these experiments covered the range from 90 to 250{sup 0}C and from 50 to 100 bar. The …
Date: September 1, 1985
Creator: Knauss, K. G.; Beiriger, W. J.; Peifer, D. W. & Piwinskii, A. J.
Object Type: Report
System: The UNT Digital Library
Water Permeability and Related Rock Properties Measured on Core Samples From the Yucca Mountain USW GU-3/G-3 and USW G-4 Boreholes, Nevada Test Site, Nevada (open access)

Water Permeability and Related Rock Properties Measured on Core Samples From the Yucca Mountain USW GU-3/G-3 and USW G-4 Boreholes, Nevada Test Site, Nevada

Core samples were measured for bulk density, grain density, porosity, resistivity, and water permeability as part of a comprehensive geologic investigation designed to determine the suitability of Yucca Mountain as a site for the containment of high-level radioactive waste products. The cores were selected at the drill sites so as to be representative of the major lithologic variations observed within stratigraphic units of the Paintbrush Tuff, Calico Hills Tuff, Crater Flat Tuff, Lithic Ridge Tuff, and Older Tuffs. Dry and saturated bulk density, grain density, and porosity measurements were made on the core samples principally to establish that a reasonable uniformity exists in the textural and mineral character of the sample pairs. Electrical resistivity measured on sample pairs tended to be lower along the plane transverse to the vertical axis of the drill core herein referred to as the horizontal plane. Permeability values, ranging from virtually zero (<.02 microdarcies) to over 200 millidarcies, also indicate a preferential flow direction along the horizontal plane of the individual tuff units. Permeability decreases with flow duration in all but the non-welded tuffs as unconsolidated particles within the pore network are repositioned so as to impede the continued flow of water through the rock. …
Date: September 1, 1994
Creator: Anderson, L. A.
Object Type: Report
System: The UNT Digital Library
Corrective Action Investigation Plan for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nevada with ROTC 1 (Revision 0, September 2000) (open access)

Corrective Action Investigation Plan for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nevada with ROTC 1 (Revision 0, September 2000)

This Corrective Action Investigation Plan contains the U.S. Department of Energy, Nevada Operations Office&#x27;s (DOE/NV&#x27;s) approach to collect the data necessary to evaluate Corrective Action Alternatives (CAAs) appropriate for the closure of Corrective Action Unit (CAU) 97 under the Federal Facility Agreement and Consent Order (FFACO). Corrective Action Unit 97, collectively known as the Yucca Flat/Climax Mine CAU, consists of 720 Corrective Action Sites (CASs). The Yucca Flat/Climax Mine CAU extends over several areas of the NTS and constitutes one of several areas used for underground nuclear testing in the past. The nuclear tests resulted in groundwater contamination in the vicinity as well as downgradient of the underground test areas. Based on site history, the Yucca Flat underground nuclear tests were conducted in alluvial, volcanic, and carbonate rocks; whereas, the Climax Mine tests were conducted in an igneous intrusion located in northern Yucca Flat. Particle-tracking simulations performed during the regional evaluation indicate that the local Climax Mine groundwater flow system merges into the much larger Yucca Flat groundwater flow systems during the 1,000-year time period of interest. Addressing these two areas jointly and simultaneously investigating them as a combined CAU has been determined the best way to proceed with corrective …
Date: September 27, 2000
Creator: Andrews, Robert & Marutzky, Sam
Object Type: Report
System: The UNT Digital Library
Summary report on the evaluation of a 1977--1985 edited sorption data base for isotherm modeling (open access)

Summary report on the evaluation of a 1977--1985 edited sorption data base for isotherm modeling

Sorption data bases collected by Los Alamos National Laboratory (LANL) from 1977 to 1985 for the Yucca Mountain Project.(YMP) have been inventoried and fitted with isotherm expressions. Effects of variables (e.g., particle size) on the isotherm were also evaluated. The sorption data are from laboratory batch measurements which were not designed specifically for isotherm modeling. However a limited number of data sets permitted such modeling. The analysis of those isotherm data can aid in the design of future sorption experiments and can provide expressions to be used in radionuclide transport modeling. Over 1200 experimental observations were inventoried for their adequacy to be modeled b isotherms and to evaluate the effects of variables on isotherms. About 15% of the observations provided suitable data sets for modeling. The data sets were obtained under conditions that include ambient temperature and two atmospheres, air and CO{sub 2}.
Date: September 1, 1993
Creator: Polzer, W. L.; Beckman, R. J.; Fuentes, H. R.; Yong, C.; Chan, P. & Rao, M. G.
Object Type: Report
System: The UNT Digital Library