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Mr. Terry Lau Page 4 July 24, 1995 8. Table 2 on page 4-11 shows the analytical methods and target detection limits for soil and ground water analyses. The target detection limits for all soil analyses and total petroleum hydrocarbons as diesel and gasoline and BTEX for ground water a acceptable. The detection limits for total lead, volitile organic compounds (VOCs) , and polychlorinated biphenyls (PCBs) in ground water are too high. Total lead should be analyzed using atomic adsorption istead of inductively coupled plama to get a lower detection limit. The Board's contract labs are able to achieve a detection of 10 µg/1 for total lead using USEPA Method 239.1. VOCs should be analyzed by either USEPA Method 601/602 or 8260. Enclosure 4, which compares the detection limits of these methods for VOCs which have been found at landfills, shows that Method 624 provides the highest detection limits. Regarding PCBs, the Board's contract labs can achieve detection limits of 0.2 to 5.0 Ug/l. Your lab should attempt to attain the 0.2 µg/1 detection limit since the USEPA's MCL of 0.5 yg/l would likely be the water quality goal for PCBs. Response: The RWQCB's recommended analytical methods will be used to achieve the desired detection limits for total lead, volatile organic compounds (VOCs), and polychlorinated biphenyls (PCBs). 9. Section 5 of the work plan describes the importance of a quality assurance/quality control program but does not specify the procedures _ to ensure collection of quality data. The work plan also states that the laboratory will perform tests on method blanks, surrogate spikes, matrix spikes, and duplicate spikes to ensure the quality of analytical activities but does not specify -when these analyses will be conducted. Response: The field investigation will use soil and groundwater sample collection methods recommended by county, state, and federal regulatory agencies. Laboratory quality assurance/quality control procedures will determine the frequency of method blanks, surrogate spikes, matrix spikes, and duplicate samples. All contracted laboratories (i.e. Sequoia Analytical) will be state-certified and licensed laboratories from the Navy's preferred analytical laboratory list. 10. Table 4 on Page 7-1 shows a Board review start date of 19 May 1995. I received the report only on 7 June 1995. Nonetheless. I will meet the completion date of 18 July 1995. Table 7-1 also shows no time allotment for Board review of the Final RI report. Response: A revised project schedule will include 45 calendar days for regulatory board review of the Final RI Report.