H-Area Acid/Caustic Basin groundwater monitoring report. Second quarter 1995

The four monitoring wells at the H-Area Acid/Caustic Basin are sampled quarterly as part of the Savannah River Site (SRS) Groundwater Monitoring Program and to comply with a consent decree signed May 26, 1988, by the US District Court (District of South Carolina, Aiken Division). During second quarter 1995, groundwater from the HAC wells was analyzed for selected heavy metals, herbicides/pesticides, indicator parameters, major ions, radionuclide indicators, and other constituents. Monitoring results that exceeded the final Primary Drinking Water Standards (PDWS), the SRS flagging criteria, or the SRS turbidity standard are the focus of this report. During second quarter 1995, tritium exceeded the final PDWS in all four HAC wells, with activities from 2.3E + 01 to 4.47E + 01 pCi/mL. Aluminum exceeded its Flag 2 criterion in all four HAC wells, ranging from 77.1 to 178 {micro}g/L. Iron exceeded its Flag 2 criterion in wells HAC 1, 2, and 3; the maximum value was 1,680 {micro}g/L in well HAC 2. Groundwater flow direction in the water table beneath the H-Area Acid/Caustic Basin was to the northwest during second quarter 1995, consistent with historical trends. Throughout the last two years, the groundwater flow direction has been consistently to the northwest or the north-northwest