One of three candidate repository sites for high-level radioactive waste packages is located at Yucca Mountain, Nevada, in rhyolitic tuff 700 to 1400 ft above the static water table. Calculations indicate that the package environment will experience a maximum temperature of {similar_to}230{sup 0}C at 9 years after emplacement. For the next 300 years the rock within 1 m of the waste packages will remain dehydrated. Preliminary results suggest that the waste package radiation field will have very little effect on the mechanical properties of the rock. Radiolysis products will have a negligible effect on the rock even after rehydration. Unfractured specimens of repository rock show no change in hydrologic characteristics during repeated dehydration-rehydration cycles. Fractured samples with initially high permeabilities show a striking permeability decrease during dehydration-rehydration cycling, which may be due to fracture healing via deposition of silica. Rock-water interaction studies demonstrate low and benign levels of anions and most cations. The development of sorptive secondary phases such as zeolites and clays suggests that anticipated rock-water interaction may produce beneficial changes in the package environment.

The chemistry of diagenetically altered tuffs at a potential nuclear waste repository, Yucca Mountain, Nevada is described. These tuffs contain substantial amounts of zeolites that are highly sorptive of certain radionuclides. Because of their widespread distribution, the zeolitic tuffs could provide important barriers to radionuclide migration. Physical properties of these tuffs and of their constituent zeolites are influenced by their chemical compositions. This study defines the amount of chemical variability within diagenetically altered tuffs and within diagenetic minerals at Yucca Mountain. Zeolitic tuffs at Yucca Mountain formed by diagenetic alteration of rhyolitic vitric tuffs. Despite their similar starting compositions, these tuffs developed compositions that vary both vertically and laterally. Widespread chemical variations were the result of open-system chemical diagenesis in which chemical components of the tuffs were mobilized and redistributed by groundwaters. Alkalies, alkaline earths, and silica were the most mobile elements during diagenesis. The zeolitic tuffs can be divided into three compositional groups: (1) calcium- and magnesium-rich tuffs associated with relatively thin zones of alteration in the unsaturated zone; (2) tuffs in thick zones of alteration at and below the water table that grade laterally from sodic compositions on the western side of Yucca Mountain to calcic compositions on …

Waste package performance assessment contains three broad categories of activities. These activities are: (1) development of a hydrothermal flow and transport model to test concepts to be used in establishing boundary conditions for performance calculations, and to interface EBS release calculations with total system performance calculations; (2) development of a waste package systems model to provide integrated deterministic assessments of performance and analyses of waste package designs; and (3) development of an uncertainty methodology for combination with the system model to perform probabilistic reliability and performance analysis waste package designs. The first category contains activities that aid in determining the scope of a separate, simplified set of hydrologic calculations needed to characterize the waste package environment for performance assessment calculations. The last two activity categories are directly concerned with waste package performance calculations. A rationale for each activity under these groups is presented. All of the activities of performance assessment are either code development or analyses of waste package problems.

In 1984, the Northwest Power Planning Council (Council) amended its Fish and Wildlife Program (Program) to include an Action Plan (Section 1500), to give focus and priority directions to various aspects of the Program. Regarding improved hatchery effectiveness, Bonneville Power Administration (BPA) was requested to evaluate ongoing work under 704(h) and submit a workplan to cover future efforts. This report provides concepts for increasing hatchery effectiveness. Additionally, it proposes numerical goals for increased fish production, identifies ways to accomplish them and lists supportive objectives, project schedules, and preliminary budgeting information. Preliminary data from subbasin planning indicates a large additional need for artificially reared salmon and steelhead in the Columbia River Basin. The total need depends upon many factors and this information will be developed and refined as subbasin plans are completed. Recently constructed fish hatcheries are coming on line, and other hatcheries are expected to be prescribed. This workplan is directed at increasing fish propagation at existing facilities, as described in program Section 700. In doing this, four approaches were considered and evaluated: (1) purchasing smolts from commercial resources; (2) building additional but typical hatcheries; (3) modifying existing hatcheries to increase their production with supplemental oxygen; and (4) increasing smolt …

A set of view graphs for briefing the acquisition executive for the Uranium Mill Tailings Remedial Action (UMTRA) Project are presented.

This report provides a course in Tritium handling in vacuum systems. Topics presented are: Properties of Tritium; Tritium compatibility of materials; Tritium-compatible vacuum equipment; and Tritium waste treatment.

It is proposed to build a Nd-Fe-B based undulator on CESR ring which would provide pseudomonochromatic tunable radiation in the hard x-ray range from 4 to 15 keV. Such an intense radiation source opens unlimited possibilities for doing exciting science in material science and condensed matter physics. Here, we present the design goals for such an undulator and discuss the influence of various parameters that govern the properties of radiation from undulators. The analysis of these results leads us to select the specific design parameters of the undulator that will meet the radiation needs of the experimental program.

A batch of high-burnup fuel from the Fast Flux Test Facility (FFTF) was processed in the Solvent Extraction Test Facility (SETF) during Campaign 9. The fuel had a burnup of {similar_to}0 MWd/kg and a cooling time of {similar_to} year. Two runs were made with this fuel; in the first, the solvent contained 30% tri-n-butyl phosphate (TBP) and partitioning of the uranium and plutonium was effected by reducing the plutonium with hydroxylamine nitrate (HAN); in the second, the solvent contained 10% TBP and a low operating temperature was used in an attempt to partition without reducing the plutonium valence. The plutonium reoxidation problem, which was present in previous runs that used HAN, may have been solved by lowering the temperature and acidity in the partition contactor. An automatic control system was used to maintain high loadings of heavy metals in the coextraction-coscrub contactor in order to increase its efficiency while maintaining low losses of uranium and plutonium to the aqueous raffinate. An in-line photometer system was used to measure the plutonium concentration in an intermediate extraction stage; and based on this data, a computer algorithm determined the appropriate adjustments in the addition rate of the extractant. The control system was successfully …

One of the objectives of the Multi-Megawatt (MMW) space reactor program is to determine, within the next five years, what types of power electronic devices would be suitable for MMW space power applications. Suitable devices must be able to withstand high temperatures and high radiation fields. After investigating the literature on solid state device and miniature vacuum tube technologies, we have concluded that the miniature vacuum tube technology is, currently, the most promising. The main reason for choosing this technology, is because miniature vacuum tubes can operate at very high temperatures (775 K or potentially higher) and are tolerant to very high neutron fluence and gamma dose. Although there are still problems to be solved before miniature vacuum tubes can be used, the time required for their development will be much shorter than the five year period required by the MMW space reactor program. 13 refs., 3 figs., 3 tabs.

Each year hatcheries experience loss of eggs, fry and fingerlings due to a group of poorly defined diseases called White Spot and Coagulated Yolk. Samples of maternal blood and ovarian fluid (coelomic fluid), as well as unfertilized eggs, were collected at spawning and subsequently tested for the presence of bacteria. Our tests reveal that there is a wide range in mortality rates experienced by the progeny of different brood salmon. Microbiologic tests revealed that these eggs contained a variety of both Gram positive and Gram negative bacteria within their yolk and that the fluids from the females who produced these lots were contaminated with a variety of bacteria. In contrast the eggs and maternal fluids from the six egg lots which experienced the lowest mortalities did not contain high numbers of Gram positive bacteria and contributed only 5% of the total mortalities observed within the 30 egg lots tested. From the 60 egg lots tested over two brood years we have isolated 18 different bacterial genera containing 32 different species from within the yolk surface sterilized, unfertilized eggs. Our tests suggest that Aeromonas hydrophila, Pseudomonas (3 species) Staphylococcus aureus, Vibrio sp., Corynebacterium hoffmanii, Listeria sp. and Bacillus sp. when detected …

The primary objective of the crack-arrest studies under the Heavy-Section Steel Technology (HSST) Program is to generate data for understanding the crack-arrest behavior of prototypical pressure vessel steels at temperatures near and above the onset of the Charpy uppershelf region. Specific program goals are to: (1) extend existing K/sub Ia/ data bases to temperatures beyond those associated with the upper limit in the ASME BandPVC; (2) clearly establish that crack-arrest occurs prior to fracture-mode conversion; (3) observe the relationship between arrest data and machine/specimen compliance behavior; and (4) validate the predictability of crack arrest, stable tearing, and/or unstable tearing sequences for ductile materials. In meeting these goals, the HSST program is generating crack-arrest data over an expanded temperature range through tests involving large thermally-shocked cylinders, pressurized-thermally-shocked vessels and wide-plate specimens. This presentation will focus on data from the wide-plate specimens which have the advantage that a more significant number of data points can be obtained at affordable costs.