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with three pre-cleaned 2-inch by 6-inch brass sleeves The samples were collected at five-foot intervals, using a 140 pound hammer to advance the sampler 18 inches The number of blows required to advance the sampler in 6-inch increments was recorded on the boring logs To avoid cross contamination, the sampling equipment was washed in an alconox solution and rinsed twice with water prior to each sampling run For each sample, both ends of the lead tube were covered with aluminum sheets, capped and sealed with tape. The samples were then stored on ice and transported under chain-of- custody to McCampbell Analytical in Pacheco, CA 3.2 Logging Soil was extruded from the second brass tube and screened for the presence of organic vapors, using a PID, and the readings were recorded on the boring logs The soil was then described in accordance with the Unified Soil Classification System (see Boring Logs, Appendix B) 33 Well Completion The boring was completed as a groundwater monitoring well using a 2-inch diameter PVC casing with 0 020 screen from 29 to 49 feet The filter pack (#3 lonestar sand) was installed from 27 to 49 feet Bentonite chips were used to make a two foot plug and the well was grouted to the surface with Portland Cement 3.4 Monitoring Well Sampling On June 2 1994 theroundwater depths in all wells were measured relative to the top of g P the casing using a Sohnst water level meter. The relative piezometric levels and hydraulic gradient were determined from these data In accordance with an agreement between the PHS/EHD and Comfort Air, only MW-5 was sampled After groundwater depths were measured, a PVC bailer was used to surge MW-5 and remove sediment A two-stage submersible pump was then used to purge standing water from the well. Approximately 9 gallons of water were removed to stabilize temperature, pH Iand conductivity (see Table 1) Stabilization parameters were measured at one-gallon intervals using an ICM water analyzer After stabilization, additional water was then removed (total 25 gallons) to completely develop MW-5. All water removed from MW-5 was stored in a 55-gallon drum on-site Following stabilization and development, a water sample was collected from MW-5 using a new, disposable plastic bailer The sample was collected in three 40 ml EPA vials I Owbrad A.&S./...k I— 5 ckd.n MW ImuM-sorra...ism I