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' 08 June 2005 AGE-NC Project No. 95-0137 Page 2 of 6 monitoring well pilot borings MW9 and MW 10 at five-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. Sampling equipment was washed in an Alconox solution and double rinsed with water prior to each sampling run to minimize cross-contamination. For each sample,both ends of the leading or other selected sleeve were covered with Teflon sheets, capped and sealed with tape.The samples were properly labeled,stored on ice and transported under chain-of-custody to Cal Tech Environmental Laboratories(CTEL),a State of California Department Iof Health Services (DHS)-certified analytical laboratory. 2.1.2. Logging Soil was extruded from the remaining brass sleeves and was screened for the presence of organic vapor using an organic vapor meter(OVM)equipped with a photo-ionization detector(PID:Thermo Environmental-580, 10.0 eV, calibrated to isobutyiene); the OVM readings were recorded on a boring log. The soil was then visually described on the boring log in accordance with the Unified ' Soil Classification System (see Appendix B). 2.1.3. Well Completions Soil pilot borings MW9 and MW10 were completed as ground water monitoring wells using two-inch diameter PVC casing with 0.020-inch slotted screen installed from approximately 15 feet to 35 feet bsg in both borings with blank casing extended to the surface. The filter pack (No. 3 Lonestar sand)was installed from approximately 15 feet to 35 feet bsg.A 2-foot bentonite chip plug was then installed above the filter pack and hydrated.The wells were then grouted to near the surface with portland cement. Water-tight, traffic-rated well boxes were then installed over the wells. As-built well diagrams are depicted on the boring logs in Appendix B. 2.1.4. Laboratory Analyses of Soil Samples Selected soil samples were analyzed for: ' Total petroleum hydrocarbons quantified as gasoline (TPH-g) and diesel (TPH-d) in accordance with EPA Method 8015M; • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and methyl tertiary-butyl ether S (MTBE) in accordance with EPA Method 8260; and ' Advanced GeoEnvironmental,Inc. 1