Paper No. 13
Presentation Time: 11:15 AM


AYLOR Jr, Joseph G., Virginia Uranium, Inc, 231 Woodlawn Heights, Chatham, VA 24531, CHERMAK, John, Department of Geosciences, Virginia Tech, 4044 Derring Hall, Blacksburg, VA 24061 and BODNAR, Robert J., Geosciences, Virginia Polytechnic Institute and State University, 4044 Derring Hall, Blacksburg, VA 24061,

The Coles Hill deposit in Pittsylvania County, Virginia is one of the largest identified uranium deposits in the United States. The 440 mya deposit is hosted in the Leatherwood Granite gneiss of the Martinsville Intrusive Complex. The ore deposit is set in a structural trap against the Chatham normal fault separating the Danville Triassic basin to the east from the Smith River Allochthon to the west. Biotite gneiss is the lowest Leatherwood Granite unit and traps uranium above it. The ore is hosted in mylonite and amphibolite and the ore zone is characterized by hydrothermal fractures, sodium-metasomatism and hematization.

Initial baseline monitoring studies are underway (i.e., monitoring well installation) to develop the pre-construction, pre-operational conditions at the site and near vicinity. This baseline information is critical to provide pre-mining baseline monitoring conditions of the site which will allow impact analysis and eventual mitigation requirements to be determined.

Recent studies include but are not limited to, surface water, ground water, soils, meteorology, ecology, radiological risks, and socio-economics. The Coles Hill deposit consists of two ore bodies, both of which outcrop at the surface. Initial data from baseline studies show elevated concentrations of uranium in soils, ground water, and surface water where the deposit outcrops and are downstream compared to non-mineralized up gradient areas. For example, soil samples where the deposit outcrops contains up to 194 ppm uranium, whereas samples away from the ore body contain less than 5 ppm uranium. The water well over the north ore body contains up to 2716 µg/L unfiltered uranium with a background of less than 1 µg/L. Surface water in a pond is 3.4 µg/L for unfiltered uranium near the ore bodies but is not detected away from the ore bodies.