Hydrologic and geologic analysis of two wells in Marion County, South Carolina

Two test wells were drilled in Marion County, South Carolina in 1982. Well MRN 77 (Marion 77) was drilled to a depth of 365 ft and was used as an observation well in the Black Creek aquifer and to supply water during drilling of the deeper well. MRN 78 (Marion 78) was drilled and cored through the entire thickness of Coastal Plain sediments into the underlying basement rock to a depth of 1,225 ft. Data from the wells include description of the core samples from MRN 78, geophysical logs, zone water levels, chemical analysis of the water sampled and results of tests for mineral content. Head in MRN 78 increases with depth. The waters sampled were all sodium bicarbonate type except for the deepest zone (1,120-1,140 ft) sampled in MRN 78, which yielded a sodium chloride type water. (Lantz-PTT)