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1 is recommended that the potentiometric surface elevations be added to each well in future reports. As part of EPA's review of the Army's RTC for this comment, EPA has requested information regarding a brief evaluation of 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. This information was not included in the Report. 4. Item 6 General Comment: In the May 21, 2000 letter, EPA had requested that Figure 5.2-1 be revised to clearly show the location of the infiltration gallery (IG1) , chimney drain (CD1) , percolation ponds, and injection wells. The Army responded that "Exact locations of IG1 and CD1 are shown on the groundwater elevation contour maps for the Above Upper and Upper Horizons (figures 5.3-1 and 5.3-2) ." However, none of the figures in the Report include arrows to the northern and southern infiltration galleries, nor to the infiltration gallery and chimney drain (although they are shown on the Figures 5.3-1 and 5.3-2) . In addition, neither the percolation ponds nor the injection wells are shown on the figures in the Report. 5. item 5. Specific Comments: EPA had requested that the reason for not operating wells numbered EW013 through EW022 and EW024 through EW037 during the fourth quarter 1998 be provided. The Army's Revised Response To Comments (RRTC) only stated that none of the treatment plant #2 extraction wells were operating during 4Q98. However, Appendix H, Table H-1 (Summary of DDJC-Tracy Treatment Plant Maintenance and Shutdown Notes October 1998 through September 1999) in the Report was not revised to indicate the reasons for not operating the extraction wells. 6. Item 6. Specific Comments: EPA requested that future reports should focus on evaluating whether groundwater at wells EW003 and EW004AU will remain within the capture zone of well EW002AU to ensure that dieldrin- contaminated groundwater will be captured by the existing extraction system. However, the Report was not revised to indicate that future reports will focus on evaluating whether groundwater at wells EW003 and EW004AU will remain within the capture zone of well EW002AU. 7. Item 14. Specific Comments: EPA requested that Table 6.5-1 be modified to include the proposed sampling frequency for well LM019A once it is repaired. However, Table 6.5-1 in the Report shows that well LM019A will not be sampled in the year 2000 indicating that the well will not be repaired. Justification for not repairing well LM019 and for not including this well in the year 2000 sampling program should be provided. 2