NTS Terminal Waste Storage Project. Annual report, FY 1978 (should have been 1979)

The primary thrust of the NTS Terminal Waste Storage Project during FY 1978 was to continue an evaluation of the suitability of the Nevada Test Site (NTS) for siting a commercial spent fuel or high-level waste repository. At the beginning of the year, three primary issues were identified. They are: (1) is waste isolation at the NTS compatible with weapons testing; (2) are there suitable geohydrologic settings available on the NTS; and (3) are there suitable disposal media available at NTS. The NTS Terminal Waste Storage Project has been organized primarily to address these three issues. The southwestern area of the NTS has been identified as compatible with both current and future weapons testing. The NTS and adjacent areas of southern Nevada contain media which are probably suitable for waste isolation and which occur in a region characterized by long groundwater flow paths through sorptive media. However, utilization of the southwestern part of NTS requires that several geotechnical issues be addressed intensively. These are: (1) the potential for earthquakes at and near NTS; (2) the potential for future volcanism at possible repository sites; (3) the location and nature of faults; and (4) the characterization of the groundwater flow system from possible repository sites to places of discharge. Four potential disposal media available on the NTS were studied during FY 1978. Studies of one of these media, alluvium, were suspended due to the low near-field thermal conductivity. Studies of other potential media, granite, argillite, and tuff, will continue during FY 1979 since it appears that these media could be used for emplacement of commercial spent fuel or high-level waste. Geologic site investigations have and will continue to evaluate areas with these media