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removal of its contents using a hydraulic Hoe-Ram. The debris from the sump can subsequently be disposed of at an off-site, permitted TSD facility. A cleanup operation in the maintenance pit in Area C is expected to be successful in reducing lead and PCB contamination to acceptable levels (below 5 ppm for PCBs and lead). Therefore, demolition would be unnecessary from a technical viewpoint. Contamination in the sump in Area J is limited to 110 ppm of a single contaminant (lead), in approximately 1,600 gallons of oil. It is expected that a cleanup action after the removal of the contaminated oil will result in residual lead contamination below 5 ppm on the walls. Cleanup of this area will be technically feasible, and demolition unnecessary. Since the Navy does not wish to reuse the sump, it can subsequently be backfilled with clean soil and abandoned in place. 5.2.2 Cost Criteria The cost of cleaning up the contaminated sumps and pit is a function of the severity of the contamination problem in individual areas. For comparitive purposes, the costs of removal actions have been classified as low, medium, or high, for the three areas at Site 5. As mentioned in Section 5.2.1, concrete surfaces in the sump in Area A are expected to be acutely contaminated with lead and PCBs, due to their exposure to the contaminated sludge and liquids. A cleanup operation in this sump might therefore involve blasting off the top layer of the concrete surface in addition to the cleanup techniques mentioned in Section 4.0. This operation is expected to be a high cost option. Costs involved in demolishing existing structures and disposing of the debris in a permitted TSD facility are typically higher than those involved in cleanup operations. However, in cases like the sump in Area A, due to high levels of structural contamination, the costs for cleanup and demolition are comparable. Therefore, cleanup as well as demolition costs for Area A are both rated as high. A cleanup of the maintenance pit in Area C is expected to achieve decontamination to less than 5 ppm STLC values of PCBs and lead, using the techniques mentioned in Section 4.0. The associated costs are ranked low to medium, since the pit does not hold contaminated liquids as in Area A. Demolition of this 50-feet by 11-feet by 5-feet pit would involve disposal of a large mass of debris and is ranked a medium cost option. Contamination in the sump in Area J is limited to a single contaminant (110 ppm of lead in oil). A clean up action following the removal of oil is expected to achieve less than a 5 ppm concentration of lead in the sump. Associated costs are ranked as low to medium. Demolition and debris disposal is ranked as a medium cost option, because of the cost involved in the disposal of the debris. 18