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I W. Table 4 presents a summary of pertinent construction information for each of the wells installed. Table 4 - Monitor Well Construction Information !-• Total Borehole Depth to Screened Top of Top of uel( Ileal Depth (BGS) De (h BGS) Water (BCS) Interval (BGS) sand Ag GS) BMt2t11t4 (BGS) r^ hV1 30.5' 30.5' 25.97' 151 30' 12.83' 11.58, HIl2 48.8' 45.5' 37.89' 30- - 45' 27.67' 26.41' W3 30.4' 30.5' 28.78' 15, 30' 13.00, 11.75' 3.1 Well Development On June 17, 1988, the monitor wells were developed by a combina- tion of swabbing and bailing for a period greater than 20 minutes using a Acher-AD2 drill rig equipped with a surgeblock. Each well was first swabbed repeatedly, then bailed. Approximately 30 gallons of water was bailed from MW1, 60 gallons of water was bailed from MW2 and approximately 20 gallons of water was bailed € from MW3. This bailing removed the heavier materials from inside of the wells. For each well, the effluent was relatively sedi- ment free at the end of the development process. The swab and bailer were steam cleaned prior to first use and between each subsequent use. r- 3.2 Well Surveying 4 on December 30, 1988, the monitor wells were surveyed by WESTON personnel using a level and rod. The survey established eleva- tions to the top of the PVC casing at each well relative to an arbitrary bench mark (ABM) located on the southeast corner of the excavation on the sidewalk (see Figure 2) . The ASM was set at 100.00 feet. The relative top of casing elevations are MW1 at 91.85 feet; MW2 at 103.35 feet and MW3 at 94.06 feet. 3.3 Groundwater Sam lin Groundwater sampling was conducted on December 30, 1988. All wells were first checked for the existence of floating product by ' the use of a clear teflon bailer. Depth to water and total well depth measurements were also taken. No product layer was ob- served within any of the wells. The total petroleum hydrocarbons and organic lead samples were obtained using a clean, transparent teflon bailer lowered into each well using, clean monofillament line until the bailer was partially submerged. The bailer was retrieved and inspected visually and its contents were poured into a clean, kiln dried 1 liter, unpreserved, amber glass container and two 40 ml unpreserved airy-)er glass VOA vials. All containers were capped with teflon lined screw caps. It was necessary to lower the bailer more than once in order to obtain sufficient water samples. The wells were then bailed to purge i the well of 3 volumes of water. Each of the wells purge