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7 1 ' 05 October 2007 AGE-NC Project No.07-1537 Page 3 of 8 • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and the fuel additives methyl tertiary-butyl ether (MTBE), di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), tertiary-amyl methyl ether(TAME),tertiary butanol(TBA),ethylene dibromide(EDB)and 1,2-dichloroethane (1,2-DCA) in accordance with EPA Method 8260B. All soil borings were backfilled from total depth to surface grade by inserting hollow rods to total depth of each boring and backfilling with a portland type II cement grout mix. ' 2.2. WELL INSTALLATION Three ground water monitoring wells (MW-4 though MW-6) were installed at the site on 14 June 2007 and surveyed on 10 July 2007; the well locations are depicted on Figure 2. ' 2.2.1. Drilling and Sampling ' On 14 June 2007, three soil borings (MW4, MWS, and MW6) were advanced at the site using a CME-75 truck mounted drill rig to advance 8.25-inch diameter hollow-stem augers to a depth of 50 feet bsg. The drill rig and three-person crew were supplied by All Well Abandonment of ' Placerville, California. Auger returns generated by drilling were containerized in properly labeled Department of Transportation(DOT)-approved model 17H 55-gallon drums and were stored on-site. Soil samples were collected ahead of the drill bit using a California modified split-spoon sampler loaded with three pre-cleaned 2-inch by 6-inch stainless steel sleeves. The samples were collected from the pilot borings at 5-foot intervals,beginning at 5 feet below surface grade(bsg)using a 140- pound hammer to advance the sampler. The number of blows required to advance the sampler over each 6-inch increment of the 18-inch sampling interval was recorded on the boring logs. After ' sample recovery,both ends of the second or other selected sleeve were covered with Teflon sheets, capped and sealed with tape. ' All sample sleeves were labeled with the sample location, date, time, designation, and sampler's initials,then stored on ice and transported under chain of custody to CTEL for analysis.The samples were analyzed for the same chemical constituents listed in Section 2.1.2. All sampling equipment was washed in an Alconox solution and rinsed with water prior to each sampling run to minimize cross-contamination. Advanced GeoEvironmental,Inc.