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1 benchmark located at the intersection of Harding Way and Madison Street is the datum for all of the monitoring wells (Table l) . TABLE 1 RELATIVE GROUNDWATER ELEVATIONS Depth to Groundwater Casing Groundwater Elevation ' Well No. Elevation (below msl) (above 7/29/93 9/13/93 7/29/93 9/13/93 msl) MW-1 10. 4 47 . 16 47 .70 -36.76 -37. 30 ' MW-2 11. 96 48 . 77 49 .28 -36. 81 -37. 32 MW--4 10. 06 48 . 87 47 .41 -36. 81 -37. 35 ' MW-5 10. 82 --- 1 48 . 25 j --- -37. 43 * All measurements in feet On September 13 , the depth to groundwater was measured in all wells, and groundwater samples were collected (Table 1) . A Solinist ' water meter was used to measure water depth. After measurements were made, all wells were purged of the required minimum of three well volumes of water, using a PVC bailer. During purging, temperature, pH, and conductivity were measured at one-gallon intervals using a Hydac water analyzer (Table 2) . Purge water was stored in 55-gallon DOT drums on the site. ' Disposable plastic bailers were used to collect water samples after the wells had been purged. Three 40-m1 EPA vials were collected from each well and transmitted in a chilled container to McCampbell ' Analytical in Pacheco, California. A grab sample of the purge water stored in a 55-gallon drum near the south property boundary was also collected on September 13 . The purpose of this sample, which was collected at the request of Mr. Infurna and Ms. Reade, was to characterize the drummed water prior to disposal. ' 3.4 Well Destruction Monitoring well MW-3 was destroyed on September 13 , 1993 . V & W Drilling supplied the truck-mounted drilling rig. The casing and grout were drilled out, and the well was plugged with Portland cement from total depth (64 feet) to surface. The abandonment was witnessed by Mr. Michael Infurna of PHS/EHD. ' 5