SITE INFORMATION AND CORRESPONDENCE

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figure." Please explain the anomalous groundwater depression in the vicinity of well LM059A (Figure A-8 in Appendix A) . Item 16. Specific Comments: The RTC states that " (N) There is no evidence indicating that the measurement at the well was erroneous, although it may be anomalous. A change in the contours if the elevation is not used would not have an impact on interpretations. Therefore, no revision was made to this figure." Please explain the anomalous groundwater mounding in the vicinity of well LM067B (Figure A-11 in Appendix A) . Item 17. Specific Comments: The RTC sates that " (N) Text provides adequate information regarding the use of 1995 data. For additional information, the reader should access the 1995 annual report." The EPA comment was not addressed. Please indicate what data quality problems occurred during all sampling events in 1995. Item 18. Specific Comments: The RTC states that "(N) Chloroform concentrations in samples from PWO03 are briefly addressed in Section 9.2.1.5. Because the chloroform concentrations are not attributable to DDJC-Tracy, the trend is not discussed in the annual report." The EPA comment was not addressed. It is unclear why concentrations in PWO03 are increasing. It appears that groundwater is flowing west in this area since Section 9.2.1.5 indicates that a source exists east of PW003. However, it is unknown in which horizon PWO03 is screened (Table 2.5-1) and consequently, what the flow direction is in this horizon. Please clarify this issue to eliminate the possibility that DDJC-Tracy is the source for the increased chloroform concentrations. Item 19. Specific Comments: The RTC states that "(N) Groundwater contours did not indicate the presence of capture zones at any extraction well. A note has been added to the legends indicating that no capture zones could be identified." 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 capture zone around each operating extraction well. 4