[en] Groundwater at the H-Area Seepage Basins (HASB) is monitored in compliance with the September 30, 1992, modification of South Carolina Hazardous Waste Permit SC1-890-008-989. The monitoring wells network is composed of 130 HSB wells which monitor the three separate hydrostratigraphic units that make up the uppermost aquifer beneath the HASB. A detailed description of the uppermost aquifer is included in the Resource Conservation and Recovery Act Part B post-closure care permit application for the H-Area Hazardous Waste Management Facility submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) in December 1990. Data from 16 HSL wells are included in this report to provide additional information for the HASB. Monitoring results are compared to the SCDHEC Groundwater Protection Standard (GWPS), established in Appendix IIID-A of the permit. Historically as well as currently, nitrate, nonvolatile beta, and tritium have been among the primary constituents to exceed standards. Other radionuclides and hazardous constituents also exceeded the GWPS in the groundwater at the HASB (notably aluminum, iodine-129, strontium-90, and zinc) during the first half of 1994. Elevated constituents were found primarily in Aquifer Zone IIB2 (Water Table) and in the upper portion of Aquifer Zone IIB, (Barnwell/McBean). However, constituents exceeding standards also occurred in several wells screened in the lower portion of Aquifer Zone IIB, (Barnwell/McBean) and Aquifer Unit IIA (Congaree). Isoconcentration/isoactivity maps included in this report indicate both the concentration/activity and extent of the primary contaminants in each of the three hydrostratigraphic units during the first half of 1994. Water-level maps indicate that the groundwater flow rates and directions at the HASB have remained relatively constant since the basins ceased to be active in 1988