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during excavations at NCS Stockton, and investigations in similar soils with elevated metals at NCS Stockton. The excavation of contaminated soil associated with the sumps is evaluated in Section 4 of the EE/CA. This alternative is difficult and costly to implement as a result of the potential for permanent damage to buildings. Thus, contaminated soil associated with sumps (if present) will not be excavated, and the action will be interim. As a result of high groundwater, any release in these soils will most likely be addressed as a groundwater cleanup. Groundwater investigations will occur during the future RI. Comment 2: Page 3-4 through 3-9, ARARs; Table 3-2 As stated on Page 3-9, the Department of Toric Substances Control (DTSC) provided state applicable or relevant and appropriate requirements (ARARs) to the Navy on 23 December 1994, including the Board's ARARs. However, none of the Board's ARARs was included in Table 3-2. For your information, the Board's ARARs are again presented in Enclosures I and 2. Since the EE/CA proposes actions for soil clean up only, the ground water remediation ARARs in Enclosure 1 do not apply. However, all ARARs in Enclosure 2 apply, except Numbers S, Ila, and 11b. I Response: The Navy has reviewed the subject regulations from the state's December 23, 1994, letter. The Navy considered the subject regulations action specific because they are not location or contaminant specific. The actions selected in the EE/CA do not include discharges to waters of the state or to soil that would affect water quality. The actions evaluated for ARARs are as follows: • Removal and disposal or destruction of sump contents • Excavation and disposal of soil • Cleaning and closure of the sumps In addition, the Navy is collecting samples to determine whether contaminants were released from the sumps or whether they remain at levels posing a human health, environmental, or water quality threat after the action. The Navy has made the following determinations: • If confirmation samples collected beneath the sumps or at limits of excavation document that no contaminants are present, the regulations are not ARARs. This is because the regulations require the presence of contamination (a discharge to soil in this case). • If samples collected beneath the sumps or at the limits of excavation document that a release to soil has occurred, the Navy may waive the ARARs for this action because the action is interim and the Navy will comply with them during a subsequent final action. EECARESP.STA:& -33?IREREI:11/15/95 II:J6wit 3