Geology of the west Bear Creek site

A geological study was conducted at the Department of Energy's proposed ''tumulus'' low-level waste disposal site in west Bear Creek Valley on the Oak Ridge Reservation. The objective of the study was to describe the geologic characteristics of the site and to provide a foundation for concurrent geohydrologic studies. Methods for study included examination of existing rock core, acquisition of additional core, geophysical logging, study of sparse natural rock exposures, examination of weathered surficial bedrock, and acquisition of bedrock fracture orientation data. For construction of geologic cross sections and a geologic map, key subsurface data were projected to the surface using a typical bedrock attitude. The surface locations of these data were refined by examination of weathered bedrock. Consistent with the regional geologic setting and previous studies elsewhere in Bear Creek Valley, results of this study indicate that the site is underlain by generally uniform dipping strata of the Cambrian Conasauga Group. Detailed examination of the lithologic features of a portion of the Conasauga at the site indicates that direct application of regional stratigraphic nomenclature requires minor modification. Analysis of intermediate-scale (meter-scale) structural features leads to the development of two conceptual models. 17 refs., 11 figs.