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4 . Section 4.10, Confirmation Sampling, page 4-7 <br /> a. The first paragraph of this section, describing sidewall <br /> confirmation sampling, is confusing and inconsistent with other sections. <br /> As agreed during the March 3 technical meeting, the revised (non-biased) <br /> confirmation sampling interval will be one per sidewall. However, if the <br /> sidewall is greater than 20 feet, one sidewall sample will be collected for <br /> each 20-foot interval. All applicable sections of the Remedial Action Work <br /> Plan (including Figure 4-1) and Sampling and Analysis Plan should be revised <br /> to reflect this understanding. <br /> b. The first paragraph also explains that confirmation samples will be <br /> collected "from just above (1 foot) the capillary fringe or groundwater zone <br /> of influence/fluctuation. " As discussed during the March 3 technical <br /> meeting, in some cases the highest known contaminant concentrations were <br /> observed at shallower depths. As a result, DDJC-Tracy agreed to modify <br /> sample collection depths to correspond to the highest known contaminant <br /> concentrations for the site or portion of the site. This understanding <br /> should be reflected in Section 4.10 as well as other applicable sections of <br /> the Remedial Action Documents. <br /> 5. Table 4-2, Soil Cleanup Standard Small Excavation Sites, page 4-8 <br /> As discussed during the March 3 technical meeting, the text <br /> of this section does not explain why soil samples will not be analyzed for <br /> VOCs at SWMU 20, even though the ROD identifies soil cleanup standards for <br /> VOCs. The text should be revised to explain that DDJC-Tracy will sample and <br /> analyze for VOCs in both soil and soil gas, following completion of soil <br /> vapor extracting (SVE) at SWMU 20, to ensure the site has achieved ROD-based <br /> cleanup standards for VOCs. <br /> 6. Section 4.10, Confirmation Sampling; and Table 4-2, Soil Cleanup <br /> Standard Small Excavation Sites, page 4-8 <br /> As discussed during the March 3 technical meeting, <br /> DDJC-Tracy indicated it was planning to report the analytical results of <br /> only the site-specific CDCs listed in Table 4-2. However, based on further <br /> discussion, DDJC-Tracy tentatively agreed that a complete listing of <br /> analytical results for each method will be included in an appendix of the <br /> Remedial Action Report (s) , which presents the results of confirmation <br /> sampling. The Remedial Action Work Plan should be revised to reflect this <br /> understanding. <br /> 2 <br />