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0 2.0 SCOPE OF WORK 2.1 Groundwater Sampling Groundwater sampling at the site will include measurement of depth to water and sampling procedures followed in Appendix 3. It is anticipated that all of the site groundwater monitoring wells will be sounded for water depth. These data will be used to prepare a site groundwater surface map for the entire site for the sampling event. Table 1 is a tabulation of all groundwater and SVE wells drilled at the Gillies site to date and the recommended well abandonment procedures. SJCEHD has recommended that the groundwater sampling be conducted on the 12 groundwater wells so that if non-detection levels of TPH-diesel are now determined to be present at wells that previously had reported concentrations of TPH- diesel in groundwater than those wells may be abandoned by pressure grou�ln lieu of overdrilling. This process may provide a means to significantly reduce the costs for well abandonments at the Gillies site. A total of 12 groundwater monitoring wells will be sampled for TPH-diesel concentrations using USEPA Test Method 8015M. The locations of the wells are depicted on Figure 1. Wells to be sampled for TPH-diesel include the following: GT-MW6, GT-MW 14A and B, GT- MW 16A and B, GT-MW 17A and B, GT-MW 18A and B, GT-MW20, GT-MW31 and GT- MW32. These wells will follow protocol for groundwater sampling as presented in Appendix 2. Wells to be sampled in support of the waste oil UST evaluation will include: GT-MW6, GT- MW 14A, GT-MW 16A, GT-MW 18A, GT-MW20 and GT-MW31. Analyses of water samples from these wells will include the two metals cadmium and zinc. Analysis for cadmium will use USEPA Test Method 7131A. Analysis for zinc will use USEPA Test Method 6010B. The water samples collected for the metals analysis will be filtered in the field using a 0.45 micron filter. The water samples collected by disposable bailers will be transferred from the bailers by polyurethane tubing through a 0.45 micron disposable filter and into a 250 ml plastic bottle that has been preserved by nitric acid. Appendix 4 provides information on the field filtration system. Replicate water samples will be collected as unfiltered and placed into nitric acid preserved 250 ml plastic bottles and unpreserved 250 ml plastic bottles. All water samples will be transported to Kiff Analytical LLC,Davis California under chain of custody. The water samples that were field filtered and placed into nitric-acid preserved 250 ml plastic bottles will be analyzed immediately. The other two water samples collected from each monitoring well will be placed on hold pending analytical results of the initial water samples. 2