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respectively. Lithologic logs for these borings were made from examination of the cuttings returns at the surface(Appendix A). A portion of the cuttings were also bagged every 5 feet and screened L with a photoionization detector(PID) for volatile organic constituents(VOCs). The PID results are presented on the boring logs. Well MW5-3 is located in the northwest corner of the site providing third point for triangulation ,P g a P of the groundwater surface and monitoring groundwater along the pipeline that connected the former tanks and dispenser. Because no borings were previously drilled in this area, soil samples were collected a 5-foot intervals for geologic logging and VOC screening with the PID. No visual or olfactory indications of PHC contamination were noted in the soil samples, and all'PID readings were zero. Therefore, no soil samples from this boring were submitted to the laboratory for PHC analysis. L - 26 feet All pilot borings for the wells were drilled with 8-inch hollow stem auger to depths of about eet to allow installation of 25 feet ofwell casing. Well construction diagrams are provided in Appendix" A. Wells are constructed of about 5 feet of blank schedule 40 .polyvinyl chloride (PVC) casing' above 20 feet of 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 oft I1n surface screen the boring to about 3 feet below ground su ace 2-f( eet abov . A 2-foot thick bentonite the e. ) seal, comprising Kwik-Plug Wyoming bentonite chips, was placed on top of the filter pack and Lhydrated. The upper foot of the well boring annulus was sealed with Quikcrete (a fast-setting concrete) into which the traffic-rated vaults were set. The top of the vaults were placed several inches above ground surface and the concrete is graded away from the vaults to reduce drainage It into the wells. L3.2 WELL DEVELOPMENT Development of the Site 5 wells was conducted on May 21, 1999 by West Hazmat and field L sampling and documentation was conducted by Geomatrix. 'The wells were developed through a combination of bailing, surging, and pumping. Initially, the fines that had collected in the bottom L 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 wells,MW5-1 and LMW5-2, the bailer was able to reduce the sand content to less than 5 milligrams per liter after removal of about 20 gallons of water, at which time a submersible pump was installed. f Development.continued until physical parameters(pH,electrical conductivity, and temperature)of b the water were stable and the water was relatively clear. A total of 66 gallons (about 20 well volumes)were removed from both MW5-1 and MW5-3 during development. At well MW5-2,very Lfine sand continued to enter the well`casing throughout development and the pump could not be installed (required a sand content less than 5 mg/1). However, a total of 84 gallons (26 well t L 5 PHILIP P. Ross, R.G. �s L