Interim sanitary landfill groundwater monitoring report. 1996 Annual report

Eight wells of the LFW series monitor groundwater quality in the Steed Pond Aquifer (Water Table) beneath the Interim Sanitary Landfill at the Savannah River Site. These wells are sampled semiannually to comply with the South Carolina Department of Health and Environmental Control Modified Municipal Solid Waste Permit 025500-1120 and as part of the SRS Groundwater Monitoring Program. Trichlorofluoromethane and 1,1,1-trichloroethane were elevated in one sidegradient well and one downgradient well during 1996. Zinc was elevated in three downgradient wells and also was detected in the associated laboratory blanks for two of those wells. Specific conductance was elevated in one background well and one sidegradient well. Barium and copper exceeded standards in one sidegradient well, and dichloromethane (a common laboratory contaminant) was elevated in another sidegradient well. Barium, copper, and dichloromethane were detected in the associated blanks for these wells, also. The groundwater flow direction in the Steed Pond Acquifer (Water Table) beneath the Interim Sanitary Landfill was to the southeast (universal transverse Mercator coordinates). The flow rate in this unit was approximately 210 ft/year during first quarter 1996 and 180 ft/yr during third quarter 1996