This report summarizes characterization studies conducted with outcrop samples of Topopah Spring Member of the Paintbrush Tuff (Tpt). In support of the Waste Package Task within the Nevada Nuclear Waste Storage Investigation (NNWSI), Tpt is being studied both as a primary object and as a constituent used to condition water that will be reacted with waste form, canister, or packing material. These studies directly or indirectly support NNWSI subtasks concerned with waste package design and geochemical modeling. To interpret the results of subtask experiments, it is necessary to know the exact nature of the starting material in terms of the intial bulk composition, mineralogy, and individual phase geochemistry. 31 figures, 5 tables.

The joint attitudes were measured in the field and plotted on aerial photos at a scale of 1:24,000. The pluton is intensely jointed, primarily as a result of cooling and movement of the magma within a northwest-trending stress field. Foliation, in general, is poorly developed, and quality varies from area to area, but it is best developed close to the contacts with the metasedimentary rocks. A prominent northwest foliation direction was observed that parallels the northwest elongation of the exposed pluton. Faults in the pluton are difficult to identify because of the homogeneity of the rock. Several faults were mapped in the northern part of the area where they have a northeast trend and intersect the northwest-trending lamprophyre dikes with little apparent displacement. A major fault that bounds the northern part of the pluton is downthrown to the north and strikes northeast. This fault offsets the alluvium, the metasedimentary rocks, and the pluton and forms fault scraps as high as 10 m. Aeromagnetic data (US Geological Survey, 1979) suggest the following: (1) the local magnetic highs in the central part of the Lone Mountain pluton are probably related to topographic highs (peaks) where the flight lines are closer to the …

IRAD GAGE vibrating-wire stressmeters were installed in the Spent Fuel Facility at the Nevada Test Site to measure the change in in-situ stress during the Spent Fuel Test-Climax (SFT-C). Although extensive pre-installation laboratory tests were conducted, they were generic in nature. Unfortunately the degree of gage-rock contact has a strong influence on gage sensitivity and cannot be predicted before installation. This report discusses the results of removing a cylindrical section of rock and gages as a unit through overcoring and the subsequent post test calibrations of the stressmeters in the laboratory. With the assumption that the gage-rock contact was not disturbed by the overcoring, the results from these calibrations compensate for varying gage-rock contact. The estimated in-situ stresses based on post test calibration data are quite consistent with those directly measured in nearby holes. The magnitude of stress change calculated from pre-installation test data is generally much smaller than that estimated from post test calibration data.

A literature review and analysis were made of corrosion and degradation processes applicable to Zircaloy cladding on spent nuclear fuel in a tuff repository. In particular, lifetime sought for the Zircaloy is 10,000 years. Among the potential failure mechanisms examined were: oxidation by steam, air, and water, including the effects of ions whose presence is anticipated in the water; mechanical overload; stress (creep) rupture; stress-corrosion cracking (SCC); and delayed failure due to hydride cracking. The conclusion is that failure due to oxidation is not credible, although a few experiments are suggested to confirm the effect of aqueous fluoride on the Zircaloy cladding. Mechanical overload is not a problem, and failure from stress-rupture does not appear likely based on a modified Larson-Miller analysis. Analysis shows that delayed hydride cracking is not anticipated for the bulk of spent fuel pins. However, for a minority of pins under high stress, there is some uncertainty in the analysis as a result of: (1) uncertainty about crack depths in spent fuel claddings and (2) the effect of slow cooling on the formation of radially oriented hydride precipitates. Experimental resolution is called for. Finally, insufficient information is currently available on stress-corrosion cracking. While evidence is presented …

We conducted a series of in-situ tests in the Climax Stock, an intrusive granite formation at the Nevada Test Site, to validate the concept of housing a nuclear waste repository in granitic crystalline rock. The thermal properties of the granite were measured with resistance heaters and thermocouple frames that had been emplaced in drilled holes in the floor of a drift 420 m below the surface. Data analysis was performed primarily by comparing the measured and calculated temperature histories, varying conductivity and diffusivity in the calculations until reasonable agreement was achieved. The best-fit value for in-situ conductivity was approximately 3.1 W/m x K, and the deduced value for in-situ diffusivity was approximately 1.2 mm{sup 2}/s. Anisotropic effects in the thermal field were less than 10%. Permeability was determined by sealing off portions of the drilled holes, using inflatable rubber packers and an air-pressurization system. We then compared the resulting decay in pressure with analytic solutions of the pressure loss from a cylindrical source in an infinite isotropic medium, obtaining a permeability of approximately 1 nanodarcy (nD) at about 30{sup 0}C. As the temperature increased, the permeability decreased to about 0.2 nD at about 50{sup 0}C and became too small to …

Recently, there is increased concern that radiocolloids may act as a rapid transport mechanism for the release of radionuclides from high-level waste repositories. The role of colloids is, however, controversial because the necessary data and assessment methodology have been limited. Evidence is accumulating to indicate that colloids are an important consideration in the geological disposal of nuclear waste. To quantitatively assess the role of colloids, the TRACR3D transport code has been enhanced by the addition of the population balance equations. This new version of the code can simulate the migration of colloids through combinations of porous/fractured, unsaturated, geologic media. The code was tested against the experimental laboratory column data of Avogadro et al. in order to compare the code results to both experimental data and an analytical solution. Next, a low-level radioactive waste site was investigated to explore whether colloid migration could account for the unusually rapid and long transport of plutonium and americium observed at a low-level waste site. Both plutonium and americium migrated 30 meters through unsaturated volcanic tuff. The nature and modeling of radiocolloids are discussed along with site simulation results from the TRACR3D code. 20 references.

A demonstration of the short-term storage and subsequent retrieval of spent nuclear fuel assemblies was successfully completed at the US Department of Energy`s Nevada Test Site. Nearly 1000 instruments were deployed to monitor the temperature of rock, air, and metallic components of the test; displacements and stress changes within the rock mass; radiation dosage to personnel and to the rock; thermal energy input; characteristics of the ventilation airstream; and the operational status of the test. Careful selection, installation, calibration, and maintenance of these instruments ensured the acquisition of about 15.3 x 10{sup 6} high-quality data points. With few exceptions, the performance and reliability of the instrumentation and associated data acquisition system (DAS) were within specified acceptable limits. Details of the performance and reliability of the instrumentation are discussed in this report. 42 figs., 32 tabs.

An experimental matrix has been conducted that will allow evaluation of the effects of waste package constituents on the waste form release behavior in a tuff repository environment. Tuff rock and groundwater were used along with 304L, 316, and 1020M ferrous metals to evaluate release from uranium-doped MCC 76-68 simulated waste glass. One of the major findings was that in the absence of 1020M mild steel, tuff rock powder dominates the system. However, when 1020M mild steel is present, it appears to dominate the system. The rock-dominated system results in suppressed glass-water reaction and leaching while the 1020M-dominated system results in enhanced leaching - but the metal effectively scavenges uranium from solution. The 300-series stainless steels play no significant role in affecting glass leaching characteristics. 6 refs., 28 figs., 5 tabs.

Four basic physical processes, thermal, hydrological, mechanical and chemical, are likely to occur in 11 different types of coupling during the service life of an underground nuclear waste repository. A great number of coupled processes with various degrees of importance for geological repositories were identified and arranged into these 11 types. A qualitative description of these processes and a tentative evaluation of their significance and the degree of uncertainty in prediction is given. Suggestions for methods of investigation generally include, besides theoretical work, laboratory and large scale field testing. Great efforts of a multidisciplinary nature are needed to elucidate details of several coupled processes under different temperature conditions in different geological formations. It was suggested that by limiting the maximum temperature to 100{sup 0}C in the backfill and in the host rock during the whole service life of the repository the uncertainties in prediction of long-term repository behavior might be considerably reduced.

The FY 1983 laboratory and field studies related to the Radionuclide Migration project are described. Results are presented for radiochemical analyses of water samples collected from the RNM-1 well and the RNM-2S satellite well at the Cambric site. Data are included for tritium, {sup 36}Cl, {sup 85}Kr, {sup 90}Sr, {sup 129}I, and {sup 137}Cs. Preliminary results from water collection at the Cheshire site are reported. Laboratory studies emphasize the sorptive behavior of tuff and its dependence on mineralogy. 18 references, 7 figures, 13 tables.

Daily newspaper from Hereford, Texas that includes local, state, and national news along with advertising.

In February 1983, the US Department of Energy identified the Richton dome site as one of the nine potentially acceptable sites for a mined geo

Daily newspaper from Hereford, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Tulia, Texas that includes local, state and national news along with extensive advertising.

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.

Monthly student magazine published by the newspaper staff of Hardin-Simmons University. According to page 2, "Reata is a non-profit news magazine, published once each month during the fall and spring semesters at Hardin-Simmons University, Abilene, Texas 79698, serving as a laboratory project and to some extent, a forum of student views."

Proceedings of the 19th regional archeological symposium including the text of papers presented during the conference. Also includes meeting minutes for the April 9, 1983 SWFAS Executive Committee and the by-laws for SWFAS.

Weekly newspaper from Tulia, Texas that includes local, state and national news along with extensive advertising.

Daily newspaper from Hereford, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Hereford, Texas that includes local, state, and national news along with advertising.

This bibliography contains information on high-level radioactive wastes included in the Department of Energy's Energy Data Base from August 1982 through December 1983. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. 1452 citations.

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.

Newsletter of the Institute of Latin American Studies discussing activities and research at the Institute, news from Latin America, and other related topics of interest.

Daily newspaper from Hereford, Texas that includes local, state, and national news along with advertising.