Subsurface leachate migration from a reject coal pile in South Carolina

Transport of contaminants from coal storage areas through the rooting zone has the potential to negatively affect shallow ground water and terrestrial vegetation. Reject coal piles represent a worst-case scenario for contamination from coal storage areas because of the long residence time of the coal. Preliminary hydrologic data were collected from an area of stressed vegetation adjacent to an inactive ash basin and reject coal pile in South Carolina. The water table is near the surface (< 60 cm) in this wetland area and water movement is primarily to the west, toward the Savannah River. Acid leachate migration from the reject coal pile has contaminated the water-table aquifer with sulfate (up to 22 200 mg L^?1) and metals (Fe to 9560 mg L^?1) Al to 1110 mg L^?1) A shallow plume of contaminated ground water parallels the reject coal pile and is elongated in the direction of ground-water movement. The plume is migrating westward at a calculated velocity range of 6.3 to 10.4 m yr^?1. Leachate migration from the reject coal has produced a highly acidic (pH down to 2.2) and highly saline (EC to 11.8 dS m^?1) rooting zone and is most likely responsible for the stressed vegetation in the study area.