In 1973 the Utah Geological and Mineral Survey drilled sixteen core holes in the P.R. Spring and Hill Creek oil-impregnated sandstone deposits in the southeast Uinta Basin, Uinta County, Utah (figures 1 & 2). The holes were drilled in cooperation with the U.S. Bureau of Mines under a grant from that agency. The purpose of the coring program was to obtain information on oil-impregnation on the sandstones of the upper Douglas Creek Member of the Green River Formation (figure 3). All the core holes penetrated oil-impregnated sandstone.