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The STLC values are normally much more stringent than the TTLC value for a particular sample, and therefore, the STLC calues drive the cleanup. Rationale behind this comparative analysis is described in Section 3.3. The sumps and pit in Areas A, C, and J will be decontaminated during the removal actions to levels below the STLC for each contaminant. These STLC values for the contaminants of concern are listed in Table 1. The following description characterizes the sumps and pit in each of the three areas and defines a scope of work for each of them. 2.1 AREA A - DRAINAGE SUMP This area was used by the Defense Industrial Plant Equipment Center (DIPEC) until approximately 1976. Coolants and other industrial liquids from radiators and heat exchangers were flushed into a floor sump located in the east end of Building 816B (Figure 1). The liquids were pumped or gravity-fed to a 4-inch pipe that carried the liquids outside the building where they were allowed to enter a storm drainage swale that was connected to the stormwater drainage system for the base facility. The concrete sump, no longer in use, is 48 inches long by 20 inches wide by 30 inches deep, and is located in an unoccupied part of Building 816B. Figure 2 shows a cross section and a plan view of the sump. The sump still holds about 18 inches of liquid and sludge corresponding to a volume of 75 gallons. The 4-inch drain pipe is located above the liquid level and extends in a northeasterly direction for about 90 feet from the building. The pipe terminates aboveground in a swale that drains east and connects with the base storm drainage system. The sump contains 18 inches of oily liquid and sludge. Approximately 2 inches of oil is floating on 12 inches of water, with 4 inches of sludge at the bottom of the sump. The sludge and oil/water samples were analyzed for priority pollutant metals (Sb, As, Be, Cd, Cr, Cu, Pb, Hg, Ni, Se, Ag, TI, Zn), polychlorinated biphenyls (PCB), toxic metals, and volatile organic compounds (VOC). The results were compiled by ERM- West (1989a). Results of the analyses of the sump contents show lead in the sludge and oil at levels exceeding ten times the STLC, and cadmium in the water at levels exceeding the STLC. Table I shows the contaminant concentrations and volumes of oil, water, and sludge to be handled. 4