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YUCCA MOUNTAIN SITE DESCRIPTION
The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, …
Date:
April 16, 2004
Creator:
Simmons, A. M.
Object Type:
Report
System:
The UNT Digital Library
The origin and history of alteration and carbonatization of the Yucca Mountain ignimbrites. Volume I
This document contains Volume I of the report entitled The Origin and History of Alteration and Carbonatization of the Yucca Mountain Ignimbrites by Jerry S. Szymanski and a related correspondence with comments by Donald E. Livingston. In the Great Basin, the flow of terrestrial heat through the crust is affected in part by the flow of fluids. At Yucca Mountain, the role of fluids in crustal heat transport is manifested at the surface by youthful calcretes, sinters, bedrock veins, hydrothermal eruption breccias and hydrothermal alteration. This report discusses evidence for recent metasomatism high in the stratigraphic section at Yucca Mountain. Over the last several hundred years, episodes of calcite emplacement contemporaneous with local mafic volcanism have occurred at intervals that are not long in comparison with the isolation time required for a High-Level Radioactive Waste repository.
Date:
April 1, 1992
Creator:
Szymanski, J. S.
Object Type:
Report
System:
The UNT Digital Library
A strategy to seal exploratory boreholes in unsaturated tuff; Yucca Mountain Site Characterization Project
This report presents a strategy for sealing exploratory boreholes associated with the Yucca Mountain Site Characterization Project. Over 500 existing and proposed boreholes have been considered in the development of this strategy, ranging from shallow (penetrating into alluvium only) to deep (penetrating into the groundwater table). Among the comprehensive list of recommendations are the following: Those boreholes within the potential repository boundary and penetrating through the potential repository horizon are the most significant boreholes from a performance standpoint and should be sealed. Shallow boreholes are comparatively insignificant and require only nominal sealing. The primary areas in which to place seals are away from high-temperature zones at a distance from the potential repository horizon in the Paintbrush nonwelded tuff and the upper portion of the Topopah Spring Member and in the tuffaceous beds of the Calico Hills Unit. Seals should be placed prior to waste emplacement. Performance goals for borehole seals both above and below the potential repository are proposed. Detailed construction information on the boreholes that could be used for future design specifications is provided along with a description of the environmental setting, i.e., the geology, hydrology, and the in situ and thermal stress states. A borehole classification scheme based …
Date:
April 1, 1994
Creator:
Fernandez, J. A.; Case, J. B.; Givens, C. A. & Carney, B. C.
Object Type:
Report
System:
The UNT Digital Library
Site characterization progress report: Yucca Mountain, Nevada. Number 15, April 1--September 30, 1996
During the second half of fiscal year 1996, activities at the Yucca Mountain Site Characterization Project (Project) supported the objectives of the revised Program Plan released this period by the Office of Civilian Radioactive Waste Management of the US Department of Energy (Department). Outlined in the revised plan is a focused, integrated program of site characterization, design, engineering, environmental, and performance assessment activities that will achieve key Program and statutory objectives. The plan will result in the development of a license application for repository construction at Yucca Mountain, if the site is found suitable. Activities this period focused on two of the three near-term objectives of the revised plan: updating in 1997 the regulatory framework for determining the suitability of the site for the proposed repository concept and providing information for a 1998 viability assessment of continuing toward the licensing of a repository. The Project has also developed a new design approach that uses the advanced conceptual design published during the last reporting period as a base for developing a design that will support the viability assessment. The initial construction phase of the Thermal Testing Facility was completed and the first phase of the in situ heater tests began on …
Date:
April 1, 1997
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Engineered Materials Characterization Report for the Yucca Mountain Site Characterization Project, Volume 3, Revision 1, Corrosion Data and Modeling
The Engineered Materials Characterization Report (EMCR) serves as a source of information on the properties of materials proposed as elements in the engineered barrier system (EBS) for the Yucca Mountain nuclear waste repository. Volume 3 covered the corrosion data and modeling efforts. The present report is a revision to Volume 3 and updates information on the corrosion (and other degradation modes) behavior of candidate materials for the various components of the EBS. It also includes work on the performance modeling of these materials. Work is reported on metallic barriers, basket materials, packing/backfill/invert materials, and non-metallic materials.
Date:
April 1, 1998
Creator:
McCright, R. D.
Object Type:
Report
System:
The UNT Digital Library
Late cenozoic evolution of Fortymile Wash: Major change in drainage pattern in the Yucca Mountain, Nevada region during late miocene volcanism
The site characterization of Yucca Mountain, NV as a potential high level nuclear waste repository includes study of the surficial deposits as a record of the paleoenvironmental history of the Yucca Mountain region. An important aspect of this history is an understanding of the evolution of paleogeography leading to establishment of the present drainage pattern. Establishment of drainage basin evolution is needed before geomorphic response to paleoclimate and tectonics can be assessed, because a major change in drainage basin geometry can predominantly affect the sedimentary record. Because alluvial aquifers are significant to regional hydrology, a major change in surface drainage resulting in buried alluvium could have hydrogeologic significance. In this paper, we report on geologic evidence for a major modification in surface drainage pattern in the Yucca Mountain region, resulting in the probable establishment of the Fortymile Wash drainage basin by latest Miocene time.
Date:
April 1, 1994
Creator:
Lundstrom, S.C. & Warren, R.G.
Object Type:
Article
System:
The UNT Digital Library
Flow and transport simulations using T2CG1, a package of conjugate gradient solvers for the TOUGH2 family of codes
This report discusses the details of modifications made to the TOUGH2 family of codes to complement its direct solver which significantly increases the size of problems solved by the TOUGH2 code. With this modification, the TOUGH2 system is being tested in multiphase, multicomponent fluid and heat flow problems related to vadose zone hydrology, nuclear waste disposal, and environmental remediation.
Date:
April 1, 1995
Creator:
Moridis, G. & Pruess, K.
Object Type:
Report
System:
The UNT Digital Library
The effect of rock fragments on the hydraulic properties of soils
Many soils contain rock fragments the sizes of which are much larger than the average pore size of the sieved soil. Due to the fact that these fragments are often fairly large in relation to the soil testing apparatus, it is common to remove them before performing hydrologic tests on the soil. The question then arises as to whether or not there is a simple way to correct the laboratory-measured values to account for the fragments, so as to arrive at property values that can apply to the soil in situ. This question has arisen in the surface infiltration studies that are part of the site characterization program at Yucca Mountain, where accurate values of the hydraulic conductivities of near-surface soils are needed in order to accurately estimate infiltration rates. Although this problem has been recognized for some time, and numerous review articles have been written there are as yet no proven models to account for the effect of rock fragments on hydraulic conductivity and water retention. In this report we will develop some simple physically-based models to account for the effects of rock fragments on gross hydrological properties, and apply the resulting equations to experimental data taken from the …
Date:
April 1, 1995
Creator:
Zimmerman, R.W. & Bodvarsson, G.S.
Object Type:
Report
System:
The UNT Digital Library
Application of the ruthenium and technetium thermodynamic data bases used in the EQ3/6 geochemical codes
Based on a critical review of the available thermodynamic data, computerized data bases for technetium and ruthenium were created for use with the EQ3/6 geochemical computer codes. The technetium data base contains thermodynamic data for 8 aqueous species and 15 solids; 26 aqueous species and 9 solids were included in the ruthenium data base. The EQ3NR code was used to calculate solubility limits for ruthenium (8 x 10{sup -16} M) in ground water from Yucca Mountain, a potential nuclear waste repository site near the Nevada Test Site (NTS). The code confirmed the essentially unlimited solubility of technetium in oxidizing conditions, such as those that are believed to exist in the unsaturated zone at Yucca Mountain and the Cambric Nuclear event site at the NTS. Ruthenium migration observed from the Cambric site was evaluated. The solubility limit for ruthenium (as the aqueous species RuO{sub 4}{sup -}) when constrained by RuO{sub 2} is approximately equal to the concentration of ruthenium found in the cavity ground water (i.e., 2.1 x 10{sup -11} vs 4.5 x 10{sup -11} M). Differences in ruthenium solubility limits between Yucca Mountain and Cambric are primarily due to differences in ground-water pH. Technetium solubility (3 x 10{sup -8} M) …
Date:
April 1, 1985
Creator:
Isherwood, D.
Object Type:
Report
System:
The UNT Digital Library
An Overview of Instability and Fingering During Immiscible Fluid Flow in Porous and Fractured Media
Wetting front instability is an important phenomenon affecting fluid flow and contaminant transport in unsaturated soils and rocks. It causes the development of fingers which travel faster than would a uniform front and thus bypass much of the medium. Water saturation and solute concentration in such fingers tend to be higher than in the surrounding medium. During infiltration, fingering may cause unexpectedly rapid arrival of water and solute at the water-table. This notwithstanding, most models of subsurface flow and transport ignore instability and fingering. In this report, we survey the literature to assess the extent to which this may or may not be justified. Our overview covers experiments, theoretical studies, and computer simulations of instability and fingering during immiscible two-phase flow and transport, with emphasis on infiltration into soils and fractured rocks. Our description of instability in an ideal fracture (Hele-Shaw cell) includes an extension of existing theory to fractures and interfaces having arbitrary orientations in space. Our discussion of instability in porous media includes a slight but important correction of existing theory for the case of an inclined interface. We conclude by outlining some potential directions for future research. Among these, we single out the effect of soil and …
Date:
April 1, 1995
Creator:
Chen, G.; Neuman, S. P. & Taniguchi, M.
Object Type:
Report
System:
The UNT Digital Library
[Josie Cantu posing next to a tree, 2]
Photograph of Josie Cantu posing next to a tree. She can be seen wearing a button-up shirt and a dark skirt. Cantu (’63) was a journalism major from San Antonio and editor for the 1962 Yucca during her junior year. She was tasked with documenting the excitement of the institution’s “University Year.” Cantu and her team of Yucca staff diligently recorded all of the momentous firsts; including the largest fall enrollment of 8,638 students, the establishment of one-way streets in downtown Denton, the use of student pictures on ID cards, and the first Big-Little Sister Skit Night.
Date:
April 4, 1962
Creator:
unknown
Object Type:
Photograph
System:
The UNT Digital Library
[Josie Cantu posing next to a tree]
Photograph of Josie Cantu posing next to a tree. She can be seen wearing a button-up shirt and a dark skirt. Cantu (’63) was a journalism major from San Antonio and editor for the 1962 Yucca during her junior year. She was tasked with documenting the excitement of the institution’s “University Year.” Cantu and her team of Yucca staff diligently recorded all of the momentous firsts; including the largest fall enrollment of 8,638 students, the establishment of one-way streets in downtown Denton, the use of student pictures on ID cards, and the first Big-Little Sister Skit Night.
Date:
April 4, 1962
Creator:
unknown
Object Type:
Photograph
System:
The UNT Digital Library
Zircaloy cladding performance under spent fuel disposal conditions; Progress report, May 1--October 31, 1989
The Brookhaven National Laboratory (BNL) Waste Materials and Environment Modeling (WMEM) Program has been assigned the task of helping the DOE formulate and certify analytical tools needed to support and/or strengthen the Waste Package Licensing Strategy. One objective of the WMEM program is to perform qualitative and quantitative analyses of irradiated Zircaloy cladding. This progress report presents the early findings of an on-going literature evaluation and the results of the numerical implementation of two models of Zircaloy creep. The report only addresses cladding degradation modes within intact, dry waste containers. Additional degradation modes will be considered when the study is expanded to include moist environments and partly failed containers. Further updates of the present analyses will also be provided.
Date:
April 1, 1990
Creator:
Pescatore, C.; Cowgill, M. G. & Sullivan, T. M.
Object Type:
Report
System:
The UNT Digital Library
Stability Constants Important to the Understanding of Plutonium in Environmental Waters, Hydroxy and Carbonate Complexation of Puo{Sub 2}{Sup +}
The formation constants for the reactions PuO{sub 2}{sup +} + H{sub 2}O = PuO{sub 2}(OH) + H{sup +} and PuO{sub 2}{sup +} + CO{sub 3}{sup 2} = PuO{sub 2}(CO{sub 3}){sup {minus}} were determined in aqueous sodium perchlorate solutions by laser-induced photoacoustic spectroscopy. The molar absorptivity of the PuO{sub 2}{sup +} band at 569 nm decreased with increasing hydroxide concentration. Similarly, spectral changes occurred between 540 and 580 nm as the carbonate concentration was increased. The absorption data were analyzed by the non-linear least-squares program SQUAD to yield complexation constants. Using the specific ion interaction theory, both complexation constants were extrapolated to zero ionic strength. These thermodynamic complexation constants were combined with the oxidation-reduction potentials of Pu to obtain Eh versus pH diagrams. 120 refs., 35 figs., 12 tabs.
Date:
April 20, 1990
Creator:
Bennett, D. A.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 569: Area 3 Yucca Flat Atmospheric Test Sites Nevada National Security Site, Nevada with ROTC 1, Revision 0
This Corrective Action Decision Document/Closure Report presents information supporting the closure of Corrective Action Unit (CAU) 569: Area 3 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada. CAU 569 comprises the following nine corrective action sites (CASs): • 03-23-09, T-3 Contamination Area • 03-23-10, T-3A Contamination Area • 03-23-11, T-3B Contamination Area • 03-23-12, T-3S Contamination Area • 03-23-13, T-3T Contamination Area • 03-23-14, T-3V Contamination Area • 03-23-15, S-3G Contamination Area • 03-23-16, S-3H Contamination Area • 03-23-21, Pike Contamination Area The purpose of this Corrective Action Decision Document/Closure Report is to provide justification and documentation supporting the recommendation that no further corrective action is needed for CAU 569 based on the implementation of the corrective actions listed in Table ES-2.
Date:
April 1, 2013
Creator:
Sloop, Christy
Object Type:
Report
System:
The UNT Digital Library
Texas Game and Fish, Volume 20, Number 4, April 1962
Monthly magazine discussing natural resources, parks, hunting and fishing, and other information related to the outdoors in Texas.
Date:
April 1962
Creator:
Texas. Game and Fish Commission. Information and Education Branch.
Object Type:
Journal/Magazine/Newsletter
System:
The Portal to Texas History
Field investigation of keyblock stability
Discontinuities in a rock mass can intersect an excavation surface to form discrete blocks (keyblocks) which can be unstable. This engineering problem is divided into two parts: block identification, and evaluation of block stability. One stable keyblock and thirteen fallen keyblocks were observed in field investigations at the Nevada Test Site. Nine blocks were measured in detail sufficient to allow back-analysis of their stability. Measurements included block geometry, and discontinuity roughness and compressive strength. Back-analysis correctly predicted stability or failure in all but two cases. These two exceptions involved situations that violated the stress assumptions of the stability calculations. Keyblock faces correlated well with known joint set orientations. The effect of tunnel orientation on keyblock frequency was apparent. Back-analysis of physical models successfully predicted block pullout force for two-dimensional models of unit thickness. Two-dimensional (2D) and three-dimensional (3D) analytic models for the stability of simple pyramidal keyblocks were examined. Calculated stability is greater for 3D analyses than for 2D analyses. Calculated keyblock stability increases with larger in situ stress magnitudes, larger lateral stress ratios, and larger shear strengths. Discontinuity stiffness controls block displacement more strongly than it does stability itself. Large keyblocks are less stable than small ones, and stability …
Date:
April 1, 1985
Creator:
Yow, J. L., Jr.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Natural analogue synthesis report, TDR-NBS-GS-000027 rev00 icn02
The purpose of this report is to present analogue studies and literature reviews designed to provide qualitative and quantitative information to test and provide added confidence in process models abstracted for performance assessment (PA) and model predictions pertinent to PA. This report provides updates to studies presented in the Yucca Mountain Site Description (CRWMS M&O 2000 [151945], Section 13) and new examples gleaned from the literature, along with results of quantitative studies conducted specifically for the Yucca Mountain Site Characterization Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate additional understanding of processes expected to occur during postclosure at a potential Yucca Mountain repository. The report focuses on key processes by providing observations and analyses of natural and anthropogenic (human-induced) systems to improve understanding and confidence in the operation of these processes under conditions similar to those that could occur in a nuclear waste repository. The process models include those that represent both engineered and natural barrier processes. A second purpose of this report is to document the various applications of natural analogues to geologic repository programs, focusing primarily on the way analogues have been used by the YMP. This report …
Date:
April 1, 2002
Creator:
Simmons, A.; Nieder-Westermann, G.; Stuckless, J.; Dobson, P.; Unger, A.J.A.; Kwicklis, E. et al.
Object Type:
Report
System:
The UNT Digital Library
The Campus Chat (Denton, Tex.), Vol. 45, No. 48, Ed. 1 Wednesday, April 18, 1962
Semiweekly student newspaper from the North Texas State College in Denton, Texas that includes local, state, and campus news along with advertising.
Date:
April 18, 1962
Creator:
York, John
Object Type:
Newspaper
System:
The Portal to Texas History
The Campus Chat (Denton, Tex.), Vol. 45, No. 45, Ed. 1 Friday, April 6, 1962
Semiweekly student newspaper from the North Texas State College in Denton, Texas that includes local, state, and campus news along with advertising.
Date:
April 6, 1962
Creator:
York, John
Object Type:
Newspaper
System:
The Portal to Texas History
The Campus Chat (Denton, Tex.), Vol. 45, No. 49, Ed. 1 Friday, April 27, 1962
Semiweekly student newspaper from the North Texas State College in Denton, Texas that includes local, state, and campus news along with advertising.
Date:
April 27, 1962
Creator:
York, John
Object Type:
Newspaper
System:
The Portal to Texas History
The Graham Leader (Graham, Tex.), Vol. [86], No. 37, Ed. 1 Thursday, April 26, 1962
Weekly newspaper from Graham, Texas that includes local, state, and national news along with advertising.
Date:
April 26, 1962
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Genetic algorithms and their use in Geophysical Problems
Genetic algorithms (GAs), global optimization methods that mimic Darwinian evolution are well suited to the nonlinear inverse problems of geophysics. A standard genetic algorithm selects the best or ''fittest'' models from a ''population'' and then applies operators such as crossover and mutation in order to combine the most successful characteristics of each model and produce fitter models. More sophisticated operators have been developed, but the standard GA usually provides a robust and efficient search. Although the choice of parameter settings such as crossover and mutation rate may depend largely on the type of problem being solved, numerous results show that certain parameter settings produce optimal performance for a wide range of problems and difficulties. In particular, a low (about half of the inverse of the population size) mutation rate is crucial for optimal results, but the choice of crossover method and rate do not seem to affect performance appreciably. Optimal efficiency is usually achieved with smaller (< 50) populations. Lastly, tournament selection appears to be the best choice of selection methods due to its simplicity and its autoscaling properties. However, if a proportional selection method is used such as roulette wheel selection, fitness scaling is a necessity, and a high …
Date:
April 1, 1999
Creator:
Parker, Paul B.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
OCRWM Bulletin
This document is the Winter 1996 ORCWM Bulletin which is a report from the U.S. Department of Energy`s Office of Civilian Radioactive Waste Management. Budget considerations and a discussion of waste policy forums are described. Several articles about the on-going site characterization at Yucca Mountain are included as a part of this bulletin.Tunnel excavations, meteorology studies, effects of seismic events, and design of a conveyor belt system are some of the topics covered in this issue.
Date:
April 1, 1996
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library