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The response does not adequately address the EPA comment. Please explain that the dieldrin contamination detected at monitoring wells LM003AA and LM015AA will be addressed by the selected remedy for dieldrin in groundwater, if appropriate. Alternately, please explain how the dieldrin contamination will be addressed. The RTC states that " (N) Concentrations of PCE (1-2 ug/L) have been detectable at LM059A since 1988. DDJC-Tracy does not consider this a "new plume" although migration from LM058AU upgradient and shallower may be indicated. " According to Appendix E, PCE was detected at LM059A in 1999 at a concentration of 5.29 ug/1, which exceeds the Maximum Contaminant Level for Drinking Water (MCL) of 5 ug/1. Since PCE concentrations detected previously at this well did not exceed the MCL, please include a discussion of the increasing trend of PCE concentrations at LM059A and include the above-mentioned suggestion that PCE may be migrating from LM05BAU to LM059A. Since PCE was detected above the MCL, please indicate how this concentration will be remediated. Item 2. General Comments: The RTC states that "(N) Some of the wells along the length of SWMU33, e.g. LM002A, are known to be within or on the edges of an identified TCE plume (See Figures 4.3-3 and 4.3-5) . Having been previously addressed in RI/FS and ROD documents, VOCs were not the focus of the soil and leachability testing effort summarized. Therefore, a discussion of TCE has not been added to this section or the attachment." Although VOCs were not the focus of the leachability testing, the fact remains that TCE was detected above the MCL at LM002A, and, therefore, should be listed as an exception in the last sentence of Section ES1.34 (Page ES-5) along with dieldrin and TPH-diesel and should be further discussed. In addition, the RTC did not address EPA's request for a discussion on how the findings of the leachability testing will affect the institutional control status of SWMU 24 and SWMU 33. Item 4. General Comments: The RTC states that "(N) If contours drawn with water level elevation data do not show evidence of hydraulic influence, no capture zone should be estimated. It has not been the practice for DDJC-Tracy to attempt to: show a capture zone for each extraction well. DDJC-Tracy contends that a combined capture zone for several closely spaced wells is a more realistic approach for hydraulic conditions at the site." It is unclear why no capture zones are depicted around operating extraction wells since groundwater extraction always creates a capture zone, even if only a very small one. Please explain whether the extraction wells are operating at their design capacity and meeting the data quality objectives which should include a determination of an acceptable radius of influence and dimensions of the capture zone around each well. Since every operating extraction well has an associated capture zone, please revise the figures to indicate a small 2