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areas will involve the process of a Remedial Investigation/Feasibility Study (RI/FS). The tasks associated with the three areas at site 5 are listed below. Area A: Removal of Sump Contents (Building 816B). Area C: Cleaning the locomotive service pit and removal of sediments from the sediment trap (Building 816B). Area J: Removal of sump contents (Building 517). This final EE/CA summarizes the site characteristics, identifies the removal action objectives and alternatives, screens the removal action alternatives, recommends the preferred response action and develops a project cost estimate. The review comments received from the regulatory agencies will be incorporated into the revised final EE/CA. The Navy will use the information obtained from the EE/CA, to develop an Action Memorandum. The EE/CA will also serve as a basis for developing removal action plans and specifications. 2.0 SITE CHARACTERISTICS Areas A through J at Site 5 have been characterized in an investigation of soil and ground-water contamination conducted by ERM-West (1989). The investigation provides data on the extent of contamination in the above areas. A summary of contaminants of concern and their concentrations in Areas A, C and J, based on the ERM-West report (Volume I, 1989), is presented in Table 1. The contaminants of concern and their concentrations listed in Table 1 are from samples of the contents of the sumps and pit in Areas A, C and J. Soil surrounding the sumps/pit was previously investigated (ERM-West, 1989) to a limited extent. Contamination was found in one soil sample each in Areas A and C out of a total of 30 and 11 samples taken respectively. Soil around the sump in Area J showed no evidence of contamination. As noted in Section 1.0, excavation/remediation of contaminated soils in Areas A, C, and J will be undertaken under a separate task. This EE/CA does not incorporate excavation and remediation of any contaminated soils. For comparative purposes, concentrations of contaminants in sump contents determined in each area were compared to the California Total Threshold Limit Concentrations ("ITLC) and ten times the Soluble Threshold Limit Concentrations (STLC). Total concentrations that exceed the TTLC are considered to be hazardous, and a remedial action, therefore, warranted. Similarly, if soluble concentrations exceed the STLC, the material is deemed hazardous. In situations where STLC data on a contaminant are unavailable, a concentration value ten times the STLC, is compared with the total concentration of the contaminant in the medium. In case the total concentration excceds ten times the STLC value, and STLC test is deemed necessary. 2