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' 0 ' 26 January 2007 AGE-NC Project No. 01-0839 Page 4 of 12 augers. The drill rig and three-man crew were provided by Mitchell Drilling Environmental of ' Eureka,California. Soil samples in the 60-foot pilot borings(V W 1,V W3,and V W6)were collected ahead of the drill bit using a California modified, 18-inch split-spoon sampler loaded with three pre- cleaned,2-inch by 6-inch brass sleeves.The samples were collected from the pilot borings at 5-foot intervals,beginning at 5 feet 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 middle sleeve were covered with Teflon sheets, capped, and sealed with tape.No soil samples were collected from the 30-foot borings (VW2, VW4, and VW5). 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 for the petroleum hydrocarbon constituents listed in Section 2.2.. All sampling equipment was washed in an Alconox solution and rinsed with water prior to each ' sampling run to minimize cross-contamination.Soil cuttings generated from drilling activities were stored on-site in properly labeled,Department of Transportation(DOT)-approved 55-gallon drums pending proper disposal. The soil vapor extraction well locations are depicted on Figure 2. 1 3.2. LOGGING ' Soil was extruded from the remaining brass sleeves and visually described by an AGE geologist in ' accordance with the Unified Soil Classification System (USCS; see Appendix D for boring logs). ' 3.3. WELL COMPLETIONS Pilot borings VW 1,VW3, and VW6 were completed as vapor extraction wells VW-1, VW-3, and ' VW-6 using 2-inch diameter, Schedule 40 polyvinylchloride(PVC)casing with 0.020-inch slotted screen installed from 45 feet to 60 feet bsg.Pilot borings VW2,VW4,and V W5 were completed as vapor extraction wells VW-2, VW-4, and VW-5 using 2-inch diameter, Schedule 40 PVC casing ' with 0.020-inch slotted screen installed from 15 feet to 30 feet bsg. The filter pack(No. 3 Lonestar sand)was installed from 43 feet to 60 feet bsg in wells W-1,VW-3,and VW-6 and from 13 feet to 30 feet in wells VW-2, VW-4, and VW-5 and a nominal 2-foot bentonite chip plug was installed ' above the filter pack in each well and hydrated. The remaining annular space was filled to near the surface with aportland cement grout mix and water-tight,traffic-rated well boxes were installed over the wells. As-built well diagrams are depicted on the boring logs in Appendix D. ' Advanced GeoEnvironmental,Inc.