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1 rinsate from the auger wash was placed into 55-gallon DOT 17 E/H drums and labeled Sot) cuttings were placed upon and covered with 6-mil polyethylene sheeting ' Well construction materials consisted of 2-inch diameter schedule 40 PVC casing and screen with flush threaded points Prior to installation, the PVC casing and screen was washed with a high- pressure,high-temperature cleaner The annular space around the slotted interval was back-filled ' with washed, kiln-dried, graded #2/12 sand The sand was placed through the hollow stem auger to a level two feet above the slotted interval A three-foot layer of 114-inch bentonite pellets was placed above the sand pack and hydrated with potable water Neat cement was placed above the ' bentonite pellet seal by the tremie method A water-tight, traffic-rated vault was installed at surface grade at each well location A SJPHS inspector was present during the well cementing operations tThe wells were developed by surging, bailing and pumping until the water reached a degree of clarity The well construction details are presented on the Boring Logs Figures 4 through 9 5.0 ELEVATION SURVEY The relative elevations at the top of casing of the two additional wells and one existing well were determined using a differential leveling process and an engineer's level The elevations of the wells were referenced to an existing brass benchmark located approximately 34 feet southwest of MW-4 The benchmark was stamped "BM 98 66" A summary of the elevation survey data is presented in Table 1 TABLE 1 ELEVATION SURVEY 1 Well Number Top of Casing Elevation in Feet MW-4 9869 ' MW-5 9828 MW-6 9770 Elevations Referenced to Benchmark "98 66" ' 6.0 GROUNDWATER SAMPLING AND ANALYSIS ' Prior to sampling, the depth to water was measured utilizing an electric sounding tape The top of the groundwater surface in the wells and the bottom of the wells were sampled for visual observations using a clear acrylic bailer The groundwater samples were collected and examined ' for the presence of odors and for indications of petroleum product The wells were then purged of at least four well volumes Parameters for pH, electrical conductivity, and temperature were measured after removal of each well volume Consistency of these measured properties indicates that fresh water is being drawn from the aquifer A groundwater sampling log was maintained for each well (refer to Figures 10 to 12) The groundwater removed during purging was placed into 55-gallon DOT 17 E/H drums and labeled ' 3 Associates