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1 0 All of the wells are located within a few feet of corresponding previous Geoprobe borings, which ' were drilled to depths of about 40 feet Soil samples were collected from the new borings for these wells at depths of 25 and 30 feet to fill in unsampled depth intervals m the Geoprobe borings The ' samples were collected in brass liners within a modified spht-spoon sampler driven ahead ofthe drill string The liners were removed from the sampler,the ends sealed with Teflon tape and plastic caps, and the caps were held in place with rubber tape Samples were labeled,placed in chilled ice chests, and delivered under chain-of-custody procedures to Precision Enviro-Tech Analytical Laboratory (PET), a California DHS-certified laboratory, for analysis of BTEX and TPHg Laboratory analytical reports and chains of custody are included in Appendix B ' Litholo c logs for the new borings were made from examination of the cuttings returns at the 81 g g g ' surface(Appendix A) Portions of the cuttings were also bagged every 5 feet and screened with a photoionization detector (PID) for volatile organic constituents (VOCs) The PID results are presented on the boring logs ' All pilot borings for the wells were drilled with 8-inch hollow-stem auger to depths of about 36 to 40 feet to allow installation of 35 feet of well casing(Appendix A) Wells are constructed of about ' 10 feet of blank, 2-inch diameter, schedule40 polyvinyl chloride(PVC) casing above 25 feet of 2- inch diameter, 0 02-inch factory-slotted PVC screen All casing is threaded and rubber gasketed Filter pack, comprising No 3 Lonestar sand,was installed through the augers from the bottom of the boring to about 7 feet below ground surface(3-feet above the screen) A 3-foot thick bentonite seal, comprising Kwik-Plug Wyoming bentonite chips, was placed on top of the filter pack and ' hydrated The upper 4 feet of the well boring annulus was sealed with Quikcrete (a fast-setting concrete) into which the traffic-rated vaults were set The tops of the vaults were placed several inches above ground surface and the concrete was graded away from the vaults to reduce drainage ' into the wells ' 3.2 WELL DEVELOPMENT Development of the Site 3 wells was conducted on May 21 and June 7, 1999 by West Hazmat and ' field sampling and documentation was conducted by Geomatnx and Philip P Ross,R G The wells were developed through a combination of bailing, surging, and pumping Initially,the fines that had ' collected in the bottom of the well during construction were bailed out until the bailer reached the bottom of the well Then the well was surged to set the gravel pack and establish communication with the formation The bailer was then used again to remove fines from the casing and sand pack ' On well MW3-3, the bailer was able to reduce the sand content to less than 5 mg/9 after removal of about 24 gallons of water, at which time a submersible pump was installed Development continued until physical parameters(pK electrical conductivity,and temperature)ofthe water were stable and the water was relatively clear A total of 48 gallons (about 11 5 well volumes) was ' vFpLvpn 5 PHILIP P. Ross, R.G.