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EPA Comments on the Draft Final "No Further Response Action Planned for Defense Site Environmental Reporting and Tracking System 72 (DSERTS 72)" Specific Comments 1. Specific Comment 1: The response is not adequate. The response states that detection frequencies in Table 2-1 will be changed to reflect the number of times a constituent was detected. According to Figure 2-1, dieldrin was detected eight times in eight samples, and selenium was detected seven of eight times,but Table 2-1 lists the frequency of detection as 3/8 for dieldrin and 2/8 for selenium. Please revise the table to accurately state the frequency of detections for dieldrin and selenium. 2. Specific Comment 2: The response is not adequate. We commented that the report does not discuss metals that were present in soils. Although the response states that constituents would be compared to background threshold values, the report has not been revised to include this discussion. Section 2.2.2.2 and Table 2-1 still imply that all detected analytes are presented. It appears from comparing the results in Appendix A to the background values in the Final Comprehensive RI/FS that the other detected metals were below background threshold values. Please revise the text and table to discuss that other metals were detected but were below threshold background values. 3. Specific Comment 2: The response referred the reader to the attached Sampling and Analysis Plan Addendum. Appendix D, Section D4.0 states that reporting limits will be 10 mg/kg for soil and 100 micrograms per liter for water. However, the actual reporting limits were 20 mg/kg for soil and 200 micrograms per liter for water. Please add to the appropriate subsections for soil and groundwater in Section 2 a discussion of the reason for the elevated reporting limits and the potential impact on achieving the data quality objectives of the additional TPH investigation. 4. Specific Comment 3: The response is not adequate. The maximum concentration of DDX is 1.602 mg/kg and the maximum concentration of dieldrin is 0.15 mg/kg. Both were detected in a duplicate sample from SB 1117 at 2 feet bgs during the March 2000 soil sampling. Section 2.2.3.4 states the maximum DDX concentration correctly but gives the wrong dieldrin concentration. The line for SB 1084 total DDX in Table 2-2, which presents the October 1999 results, was incorrectly revised and should be changed back to 0.299 mg/kg at 11 feet bgs. The depth of sample for SB 1117 (duplicate) in Table 2-3 should be changed to 2 feet bgs. The maximum dieldrin result in Table 2-3 should be revised to 0.15 mg/kg at 2 feet bgs. Two duplicate samples with detected results were omitted from Figure 2-2: SB 1119 at 6.5 feet bgs (SB 11 19SO002DS) and SB 1117 at 2 1