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GEOMATRIX 4.1 SOUL BORINGS May 21 and May 22, 2042, Gregg Drilling and Testing Inc. (Gregg Drilling)advanced six soil borings (SB-9 through SB-14)under Geomatrix supervision. Borings were advanced to depths ranging from 14.5 to 82 feet bgs using a Mobile B-61 hollow stem auger drill rig equipped with 8-inch diameter augers. Boring depths were based primarily on field observations of petroleum hydrocarbon-impacted soil. All drilling and soil sampling equipment was steam cleaned prior to use. Samples were collected at five-foot intervals from each boring using a Modified California drive sampler (2.5-inch diameter by 18-inches in length). Soil cores were logged by a Geomatrix geologist according to the Unified Soil Classification System (USCS) as presented in the American Society of Testing and Materials (ASTM) Standard D2488-90. Recovered soil was screened for organic vapors using a Photoionization Detector (PID). Boring logs are included in Appendix B. A minimum of three soil samples were collected for laboratory analysis from borings SB-9 through S13-12. Soil samples were collected at depths of approximately 2, 5 and 10 feet bgs in each of these borings to evaluate the presence of petroleum constituents in near surface and shallow soil. Additional soil samples were collected from SB-9, including one at a depth that correlated with the most visually affected soil within the soil column(45 ft bgs), and two sam- ples at the terminus of the boring to confirm the vertical extent of affected soil (70.5 and 81 ft bgs). The terminus samples were collected from a depth below which field observations/measurements did not indicate the presence of petroleum constituents. A minimum of two soil samples were collected for laboratory analysis from borings SB-13 and SB-14, The primary purpose of these two borings was to assess groundwater quality down- gradient of petroleum affected soil, as identified in previous investigations,by collecting grab groundwater samples. Soil samples were collected for further evaluation of the subsurface during advancement of the boring. Soil samples were collected at SB-13 at the vadose zone/groundwater interface (34.5 feet bgs)where no affected soil was encountered visually, and at the terminus of the boring(45.5 feet bgs). Soil samples were collected from SB-14 at a depth that correlates with the most visually affected soil within the soil column (40 feet bgs) and at the terminus of the boring(45 feet bgs). Soil samples were collected in 6-inch stainless steel sleeves, sealed with Teflon sheets, plastic end caps, and tape. Soil samples were labeled, sealed in plastic bags, and placed immediately I:IC3oe SaTeLS[101hLiG31.061IRrpart�Soii and Ci W Rcporidoc 5