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Yucca Mountain drift scale test progress report
The Drift Scale Test (DST) is part of the Exploratory Studies Facility (ESF) Thermal Test being conducted underground at the potential high-level nuclear waste repository at Yucca Mountain, Nevada. The purpose of the ESF Thermal Test is to acquire a more in-depth understanding of the coupled thermal, mechanical, hydrological, and chemical processes likely to be encountered in the rock mass surrounding the potential geological repository at Yucca Mountain. These processes are monitored by a multitude of sensors to measure the temperature, humidity, gas pressure, and mechanical displacement, of the rock formation in response to the heat generated by the heaters. In addition to collecting passive monitoring data, active hydrological and geophysical testing is also being carried out periodically in the DST. These active tests are intended to monitor changes in the moisture redistribution in the rock mass, to collect water and gas samples for chemical and isotopic analysis, and to detect microfiacturing due to heating. On December 3, 1998, the heaters in the DST were activated. The planned heating phase of the DST is 4 years, and the cooling phase following the power shutoff will be of similar duration. The present report summarizes interpretation and analysis of thermal, hydrological, chemical, …
Date:
January 1, 1999
Creator:
Apps, J.; Birkholzer, J.T.; Peterson, J. E.; Sonnenthal, E.; Spycher, N.; Tsang, Y. W. et al.
Object Type:
Report
System:
The UNT Digital Library
Geohydrologic data and models of Rainier Mesa and their implications to Yucca Mountain
The geohydrologic data collected at Rainier Mesa provide the only extensive observations in tunnels presently available on flow and transport in tuff units similar to those of a potential nuclear waste repository at Yucca Mountain. This information can, therefore, be of great value in planning the Exploratory Studies Facility (ESF) testing in underground drifts at Yucca Mountain. In this paper, we compare the geohydrologic characteristics of tuff units of these two sites and summarize the hydrochemical data indicating the presence of nearly meteoric water in Rainier Mesa tunnels. A simple analytic model is used to evaluate the possibility of propagating transient pulses of water along fractures or faults through the Paintbrush nonwelded tuff unit to reach the tunnel beds below. The results suggest that fast flow could occur without significant mixing between meteoric fracture water and matrix pore water. The implications of these findings on planning for the ESF Calico Hills study at Yucca Mountain are discussed.
Date:
January 1, 1993
Creator:
Wang, J. S. Y.; Cook, N. G. W.; Wollenberg, H. A.; Carnahan, C. L.; Javandel, I. & Tsang, C. F.
Object Type:
Article
System:
The UNT Digital Library
Numerical simulation of gas flow through unsaturated fractured rock at Yucca Mountain, Nevada
Numerical analysis is used to identify the physical phenomena associated with barometrically driven gas (air and water vapor) flow through unsaturated fractured rock at Yucca Mountain, Nevada. Results from simple finite difference simulations indicate that for a fractured rock scenario, the maximum velocity of air out of an uncased 10 cm borehole is 0.002 m s{sub {minus}1}. An equivalent porous medium (EPM) model was incorporated into a multiphase, multicomponent simulator to test more complex conceptual models. Results indicate that for a typical June day, a diurnal pressure wave propagates about 160 m into the surrounding Tiva Canyon hydrogeologic unit. Dry air that enters the formation evaporates water around the borehole which reduces capillary pressure. Multiphase countercurrent flow develops in the vicinity of the hole; the gas phase flows into the formation while the liquid phase flows toward the borehole. The effect occurs within 0.5 m of the borehole. The amount of water vapor leaving the formation during 1 day is 900 cm{sup 3}. This is less than 0.1% of the total recharge into the formation, suggesting that the barometric effect may be insignificant in drying the unsaturated zone. However, gas phase velocities out of the borehole (3 m s{sup {minus}1}), …
Date:
January 1, 1990
Creator:
Cooper, C.A.
Object Type:
Report
System:
The UNT Digital Library
A summary and discussion of hydrologic data from the Calico Hills nonwelded hydrogeologic unit at Yucca Mountain, Nevada
This report is a summary of available hydrologic data from in situ and laboratory testing of the Calico Hills nonwelded hydrogeologic unit, including hydraulic conductivity, porosity, saturation, pore-size distribution and parameters from curve-fits to pressure-saturation data. Sample statistics of hydraulic conductivity, porosity and saturation data for vitric, devitrified and zeolitic tuffs are presented and discussed. While a high degree of variability is observed in both laboratory and in situ hydraulic conductivity measurements, uncertainties arising from differences in size of laboratory test samples, sample handling, test procedures and insufficient number of samples point to the need for additional data of specific types to adequately characterize the unit. Hydrologic issues related to transport analysis in the Calico Hills nonwelded hydrogeologic unit at Yucca Mountain are discussed together with recommendations for future work. The compiled data are included as an appendix.
Date:
January 1, 1993
Creator:
Loeven, C.
Object Type:
Report
System:
The UNT Digital Library
1996 Milestone Report 3GQH671M Synthesis of Ground-Water Discharge Deposits Near Yucca Mountain
None
Date:
January 1, 1998
Creator:
Paces, J. B.; Whelan, J. F.; Mahan, S. A.; Bradbury, J. P.; Quade, J. & Neymark, L. A.
Object Type:
Report
System:
The UNT Digital Library
Investigations of hydro-tectonic hazards at the proposed Yucca Mountain high-level nuclear waste repository. Annual report - Nevada
This document includes several reports describing scientific studies of the origin of near surface calcite/silica deposits at Yucca Mountain, Nevada. The origin of these deposits is controversial and the authors have extended and strengthened the basis of their arguments for epigenetic, metasomatic alteration of the tuffs at Yucca Mountain. This report includes stratigraphic, mineralogical, and geochronological information along with geochemical data to support the conclusions described by Livingston and Szymanski. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date:
January 1, 1994
Creator:
Livingston, D.E.
Object Type:
Report
System:
The UNT Digital Library
Experimental investigation of hydrous pyrolysis of diesel fuel and the effect of pyrolysis products on performance of the candidate nuclear waste repository at Yucca Mountain, Nevada
It is thought that a significant amount of diesel fuel and other hydrocarbon-rich phases may remain inside the candidate nuclear waste repository at Yucca Mountain after construction and subsequent emplacement of radioactive waste. Although the proposed repository horizon is above the water table, the remnant hydrocarbon phases may react with hydrothermal solutions generated by high temperature conditions that will prevail for a period of time in the repository. The preliminary experimental results of this study show that diesel fuel hydrous pyrolysis is minimal at 200{degrees}C and 70 bars. The composition of the diesel fuel remained constant throughout the experiment and the concentration of carboxylic acids in the aqueous phases was only slightly above the detection limit (1-2 ppm) of the analytical technique.
Date:
January 1, 1994
Creator:
Jackson, K. J. & Carroll, S. A.
Object Type:
Report
System:
The UNT Digital Library
[John Biggerstaff facing right]
Photograph of John Biggerstaff for his photo as one of the Yucca yearbook's "Outstanding 34". He was awarded for his efforts within the psychology department.
Date:
January 1962
Creator:
unknown
Object Type:
Photograph
System:
The UNT Digital Library
[John Biggerstaff facing front 1]
Photograph of student John Biggerstaff posing for his photo that will be going into The Yucca for the "Outstanding 34" spread. He was awarded a place in the 34 because of his work in the Psychology department.
Date:
January 1962
Creator:
unknown
Object Type:
Photograph
System:
The UNT Digital Library
[John Biggerstaff facing front 2]
Photograph of student John Biggerstaff sitting for a photo that will be put in The Yucca's "Outstanding 34" spread. He was awarded his spot in the 34 for his work in the Psychology department.
Date:
January 1962
Creator:
unknown
Object Type:
Photograph
System:
The UNT Digital Library
[John Biggerstaff facing front 3]
Photograph of student John Biggerstaff sitting down with his arms crossed for a photo that will be placed on The Yucca's "Outstanding 34" spread. Biggerstaff earned a spot in the 34 due to his work in the Psychology department.
Date:
January 1962
Creator:
unknown
Object Type:
Photograph
System:
The UNT Digital Library
Site characterization plan: Yucca Mountain site, Nevada research and development area, Nevada: Consultation draft, Nuclear Waste Policy Act: Volume 2
The Yucca Mountain site in Nevada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in accordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site; to describe the conceptual designs for the repository and the waste package and to present the plans for obtaining the geologic information necessary to demonstrate the suitability of the site for a repository, to design the repository and the waste package, to prepare an environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. Chapter 3 summarizes present knowledge of the regional and site hydrologic systems. The purpose of the information presented is to (1) describe the hydrology based on available literature and preliminary site-exploration activities that have been or are being performed and (2) provide information to be used to develop the hydrologic aspects of the planned site characterization program. Chapter 4 contains geochemical information about the Yucca Mountain site. The …
Date:
January 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Degradation mode survey of titanium-base alloys
Of the materials reviewed, commercially pure titanium, Ti Gr 2, is the most susceptible to crevice corrosion. Ti Gr 7, 12, and 16 are likely to be resistant to crevice corrosion under the current expected Yucca Mountain repository conditions. Although Grade 7 has the greatest resistance to crevice corrosion it is also the most expensive. Although the possibility of sustained loads cracking exists, it has not yet been observed in a Ti alloys. For hydride precipitation to occur 100{degrees}C, the hydrogen concentration would need to be relatively high, much higher than the maximum amount of hydrogen allowed during the manufacture of ({alpha} Ti alloys (0.0 15 wt%). A large amount of (SCC) stress corrosion cracking data accumulated at SNL and BNL for the WIPP program and by the Canadian Waste Management Program on titanium grades 2 and 12 indicates that there is no SCC at naturally occurring potentials in various brines. Hydride-induced cracking of titanium is a possibility and therefore, further investigation of this phenomenon under credible repository conditions is warranted. One disadvantage of titanium and its alloys is that their strengths decrease rather rapidly with temperature. This is due to the strong temperature dependence of interstitial solute strengthening mechanisms. …
Date:
January 30, 1995
Creator:
Gdowski, G. E. & Ahluwalia, H. S.
Object Type:
Report
System:
The UNT Digital Library
Site characterization plan: Yucca Mountain site, Nevada research and development area, Nevada: Consultation draft, Nuclear Waste Policy Act: Volume 1
The Yucca Mountain site in Nevada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in acordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site;to describe the conceptual designs for the repository and the waste package and to present the plans for obtaining the geologic information necessary to demonstrate the suitability of the site for a repository, to design the repository and the waste package, to prepare an environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. This introduction begins with a brief section on the process for siting and eveloping a repository, followed by a discussion of the pertinent legislation and regulations. A description of site characterization is presented next;it describes the facilities to be constructed for the site characterization program and explains the principal activities to be conducted during the program. Finally, the purpose, content, organizing prinicples, and organization of this site characterization plan …
Date:
January 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Site characterization plan: Yucca Mountain site, Nevada research and development area, Nevada: Consultation draft, Nuclear Waste Policy Act: Volume 7
The Yucca Mountain site in Neavada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended and approved for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in accordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site;to describe the conceptual designs for the repository and the waste package;and to present the plans for obtaining hte geologic information necessary to demonstrate the suitability of the site for a repository, to design the repository and the waste package, to prepare and environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. This introduction begins with a brief section on the process for siting and developing a repository, followed by a discussion of the pertinent legislation and regulations. A description of site characterization is presented next;it describes the facilities to be constructed for the site characterization program and explains the principal activities to be conducted during the program. Finally, the purpose, content, organizing principles, and organization of this site characterization …
Date:
January 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Site characterization plan: Yucca Mountain site, Nevada research and development area, Nevada: Consultation draft, Nuclear Waste Policy Act: Volume 4
The Yucca Mountain site in Nevada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended and approved by the President for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in accordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site; to describe the conceptual designs for the repository and the waste package; and to present the plans for obtaining the geologic information necessary to demonstate the suitability of the site for a repository, to desin the repository and the waste package, to prepare an environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. This introduction begins with a brief section on the process for siting and developing a repository, followed by a discussion of the pertinent legislation and regulations. A description of site characterization is presented next; it describes the facilities to be constructed for the site characterization program and explains the principal activities to be conducted during the program. Finally, the purpose, content, organizing principles, …
Date:
January 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
A Hydrostratigraphic Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat-Climax Mine, Lincoln and Nye Counties, Nevada
A new three-dimensional hydrostratigraphic framework model for the Yucca Flat-Climax Mine Corrective Action Unit was completed in 2005. The model area includes Yucca Flat and Climax Mine, former nuclear testing areas at the Nevada Test Site, and proximal areas. The model area is approximately 1,250 square kilometers in size and is geologically complex. Yucca Flat is a topographically closed basin typical of many valleys in the Basin and Range province. Faulted and tilted blocks of Tertiary-age volcanic rocks and underlying Proterozoic and Paleozoic sedimentary rocks form low ranges around the structural basin. During the Cretaceous Period a granitic intrusive was emplaced at the north end of Yucca Flat. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the basin. These were integrated using EarthVision? software to develop the 3-dimensional hydrostratigraphic framework model. Fifty-six stratigraphic units in the model area were grouped into 25 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the alluvial section into 3 hydrostratigraphic units including 2 aquifers and 1 confining unit. The volcanic units in the model area are organized into 13 hydrostratigraphic …
Date:
January 1, 2006
Creator:
Nevada, Geotechnical Sciences Group Bechtel
Object Type:
Report
System:
The UNT Digital Library
Mineralogical textural and compositional data on the alteration of basaltic glass from Kilauea, Hawaii to 300 degrees C: Insights to the corrosion of a borosilicate glass waste-form. [Yucca Mountain Project]
Mineralogical, textural and compositional data accompanying greenschist facies metamorphism (to 300{degrees}C) of basalts of the East Rift Zone (ERZ), Kilauea, Hawaii may be evaluated relative to published and experimental results for the surface corrosion of borosilicate glass. The ERZ alteration sequence is dominated by intermittent palagonite, interlayered smectite-chlorite, chlorite, and actinolite-epidote-anhydrite. Alteration is best developed in fractures and vesicles where surface reaction layers root on the glass matrix forming rinds in excess of 100 microns thick. Fractures control fluid circulation and the alteration sequence. Proximal to the glass surface, palagonite, Fe-Ti oxides and clays replace fresh glass as the surface reaction layer migrates inwards; away from the surface, amphibole, anhydrite, quartz and calcite crystallize from hydrothermal fluids in contact with the glass. The texture and composition of basaltic glass surfaces are similar to those of a SRL-165 glass leached statically for sixty days at 150 {degrees}C. While the ERZ reservoir is a complex open system, conservative comparisons between the alteration of ERZ and synthetic borosilicate glass are warranted. 31 refs., 2 figs.
Date:
January 1, 1990
Creator:
Smith, D. K.
Object Type:
Article
System:
The UNT Digital Library
Theory of matrix and fracture flow regimes in unsaturated, fractured porous media
The flow behavior of a two-dimensional, unsaturated fracture-matrix system is characterized by a critical flux q*{sub f} = {phi}(S{sub s} {minus} S{sub i})D{sub m} where {phi} is matrix porosity, S{sub s} maximum matrix saturation, S{sub i} initial saturation, and D{sub m} matrix imbibition diffusivity constant. If the flux q{sub f} into the fracture satisfies q{sub f} {much_gt} q*{sub f}, the flow field is fracture-dominated; whereas, if q{sub f} {much_lt} q*{sub f}, the flow is matrix-dominated, and the system behaves as a single equivalent medium with capillary equilibrium between fracture and matrix. If the fracture entrance is ponded, the critical fracture hydraulic conductivity K*{sub f}, or corresponding critical aperture 2b* from the ``cubic law,`` controls the flow behavior instead of the critical flux. Rocks with fracture apertures 2b that are sufficiently large, b{sup 3} {much_gt} b*{sup 3}, have flow that is fracture-dominated while rocks with small aperture fractures, b{sup 3} {much_lt} b*{sup 3}, will be matrix-dominated. Numerical modeling verifies the theory and tests approximate analytical solutions predicting fracture front movement. 15 refs., 7 figs., 4 tabs.
Date:
January 1, 1991
Creator:
Nitao, J. J.
Object Type:
Article
System:
The UNT Digital Library
Conceptualization of a hypothetical high-level nuclear waste repository site in unsaturated, fractured tuff
Under the sponsorship of the US Nuclear Regulatory Commission (NRC), Sandia National Laboratories (SNL) is developing a performance assessment methodology for the analysis of long-term disposal and isolation of high-level nuclear wastes (HLW) in alternative geologic media. As part of this exercise, SNL created a conceptualization of ground-water flow and radionuclide transport in the far field of a hypothetical HLW repository site located in unsaturated, fractured tuff formations. This study provides a foundation for the development of conceptual mathematical, and numerical models to be used in this performance assessment methodology. This conceptualization is site specific in terms of geometry, the regional ground-water flow system, stratigraphy, and structure in that these are based on information from Yucca Mountain located on the Nevada Test Site. However, in terms of processes in unsaturated, fractured, porous media, the model is generic. This report also provides a review and evaluation of previously proposed conceptual models of unsaturated and saturated flow and solute transport. This report provides a qualitative description of a hypothetical HLW repository site in fractured tuff. However, evaluation of the current knowledge of flow and transport at Yucca Mountain does not yield a single conceptual model. Instead, multiple conceptual models are possible given …
Date:
January 1991
Creator:
Parsons, A. M.; Olague, N. E. & Gallegos, D. P.
Object Type:
Report
System:
The UNT Digital Library
{sup 13}C and {sup 17}O NMR binding constant studies of uranyl carbonate complexes in near-neutral aqueous solution. Yucca Mountain Project Milestone Report 3351
Valuable structural information, much of it unavailable by other methods, can be obtained about complexes in solution through NMR spectroscopy. From chemical shift and intensity measurements of complexed species, NMR can serve as a species-specific structural probe for molecules in solution and can be used to validate thermodynamic constants used in geochemical modeling. Fourier-transform nuclear magnetic resonance (FT-NMR) spectroscopy has been employed to study the speciation of uranium(VI) ions in aqueous carbonate solutions as a function of pH, ionic strength, carbonate concentration, uranium concentration, and temperature. Carbon-13 and oxygen-17 NMR spectroscopy were used to monitor the fractions, and hence thermodynamic binding constants of two different uranyl species U0{sub 2}(CO{sub 3}){sub 3}{sup 4{minus}} and (UO{sub 2}){sub 3}(CO{sub 3}){sub 6}{sup 6{minus}} in aqueous solution. Synthetic buffer solutions were prepared under the ionic strength conditions used in the NMR studies in order to obtain an accurate measure of the hydrogen ion concentration, and a discussion of pH = {minus}log(a{sub H}{sup +}) versus p[H] = {minus}log[H+] is provided. It is shown that for quantitative studies, the quantity p[H] needs to be used. Fourteen uranium(VI) binding constants recommended by the OECD NEA literature review were corrected to the ionic strengths employed in the NMR study …
Date:
January 1, 1995
Creator:
Clark, D. L.; Newton, T. W.; Palmer, P. D. & Zwick, B. D.
Object Type:
Report
System:
The UNT Digital Library
Amplitude and Frequency Characteristics of Elastic Wave Types Generated By Underground Nuclear Explosions
None
Date:
January 1, 1969
Creator:
Hays, W. W. & Murphy, J. R.
Object Type:
Report
System:
The UNT Digital Library
Nuclear technology programs; Semiannual progress report, October 1989--March 1990
This document reports on the work done by the Nuclear Technology Programs of the Chemical Technology Division, Argonne National Laboratory, in the period October 1989--March 1990. These programs involve R&D in three areas: applied physical chemistry, separation science and technology, and nuclear waste management. The work in applied physical chemistry includes investigations into the processes that control the release and transport of fission products under accident-like conditions, the thermophysical properties of metal fuel and blanket materials of the Integral Fast Reactor, and the properties of selected materials in environments simulating those of fusion energy systems. In the area of separation science and technology, the bulk of the effort is concerned with developing and implementing processes for the removal and concentration of actinides from waste streams contaminated by transuranic elements. Another effort is concerned water waste stream generated in production of 2,4,6-trinitrotoluene. In the area of waste management, investigations are underway on the performance of materials in projected nuclear repository conditions to provide input to the licensing of the nation`s high-level waste repositories.
Date:
January 1, 1992
Creator:
Harmon, J.E.
Object Type:
Report
System:
The UNT Digital Library
Chemical and mineralogical concerns for the use of man-made materials in the post-emplacement environment
In a radioactive waste repository, materials will be introduced for a variety of reasons. Some materials such as metals, bonding agents, and concrete will serve as active parts of the designed engineered barrier system (EBS). Other materials will be introduced to serve a number of purposes that include any or all of the following: surveillance (thermocouples, gauges), construction and operation (drilling rigs, roadbeds, exhaust fumes, chemical toilets, concrete, grout, rebar), lubrication (petroleum-based products, rope dressing) and other functions. Water chemistry will directly affect the corrosion of containers, the dissolution of spent fuel and waste glass and the concentration of dissolved or suspended radionuclides in water that exits breached containers. To predict the water quality requires a knowledge of the dissolution kinetics of the phases present in man-made materials, and the precipitation kinetics of product phases. The chemical evolution of man-made materials of interest to the Yucca Mountain project are by and large not presently known. Prediction of the long-term behavior (10,000 years) required of the modeling efforts is an additional layer of complexity that is not addressed by current models of water chemistry. Man-made modifications to the environment may significantly alter the thermal, chemical and radionuclide transportation attributes of the …
Date:
January 16, 1993
Creator:
Meike, A.
Object Type:
Report
System:
The UNT Digital Library