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Lo 19 October 2004 AGE-NC Project No. 04-1180 Page 3 of 7 3.1.1. Drilling and Sampling The pilot boring for monitoring well MW-1 was advanced using a CME-75HT drill rig equipped with 8.25-inch diameter hollow-stem augers. The drill rig and three-man crew was supplied by Cascade Drilling, Inc.. Auger returns generated by drilling were containerized in properly labeled Department of Transportation(DOT)-approved model 17H 55-gallon drums.and stored on-site. L" 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 brass sleeves.The samples were collected from each boring at five-foot intervals, beginning at 10 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. 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 of Health Services (DHS)-certified analytical laboratory. 3.1.2. Logging Soil was extruded from the remaining brass sleeves and screened for the presence of organic vapor using an organic vapor meter (OVM) equipped with a photo-ionization detector (PID: Thermo Environmental 58013, 10.0 eV, calibrated to isobutylene); 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 (Appendix B). 3.1.3. Well Completions The pilot boring was completed as a single-level ground water monitoring well using two-inch diameter PVC casing with 0.010-inch slotted screen installed from 35 feet to 55 feet bsg,with blank casing extending to the surface. The filter pack (No. 2/12'.Lonestar sand) was installed from approximately 32 feet to 55 feet bsg.A nominal 2-foot bentonite chip plug was then installed above the filter pack and hydrated.The well was then grouted to near the surface with portland cement,and a water-tight, traffic-rated well box was installed over the well utilizing a neat cement. 60 An as-built well diagram for well MW-1 is depicted on the boring log in Appendix B. Advanced GeoEnvironmental,Inc.