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is approximately 10 feet above the histoncally highest recorded groundwater level in the site area (35 feet in 1983) Upgradient Environmental installed groundwater monitoring well VM-1 in September 1995 Contaminated soil was detected at a depth of 25 feet, and groundwater samples collected in September and October were also contaminated Gasoline, diesel, BTEX, and several chlorinated hydrocarbons were detected in the groundwater In February 1996, Upgradient collected eight samples from the soil that had been excavated during the UST removal in 1990 This soil was stockpiled at the south end of the site The stockpile samples were transported to Sequoia Analytical, who composited them to two samples for analysis No hydrocarbons were detected in one sample, and only diesel, at a concentration of 5 mg/kg (ppm), was detected in the other(Appendix B) Therefore, with the approval of PHS/EHD, the stockpiled soil was used to backfill the excavation in April 1996 Excess soil remains stockpiled at the south end of the site, but will be disposed of at a later date 3,0 DRILLING AND SAMPLING PROCEDURES 3.1 Drilling and`Sampling On July 1 and 2, 1996, V & W Drilling of Rio Vista drilled three soil bonngs and converted two of these to monitoring wells Drilling was limited to three borings at the request of Mr Hyduke A rotary concrete cutter was used to cut three 12-inch diameter holes through the concrete pavement for the borings Prior to drilling, the depth to groundwater in VM-I was determined to be 45 feet The first boring(HP-2, Figure 2) was therefore drilled to a depth of 43 feet, and a hydropunch sampling device was pushed to 47 feet to collect a groundwater sample Water had not entered the boring after 45 minutes, so the boring was extended to a depth of 45 feet and the hydropunch was pushed to 49 feet Groundwater entered the bonng very slowly, and stabilized at a depth of 47 7 feet A groundwater sample was collected from the hydropunch before the boring was backfilled with cement grout 0 Because of the difficulty in using the hydropunch to sample HP-2, the second boring (HP-3) was drilled to a depth of 50 feet, and a grab groundwater sample was collected with a disposable bailer The boring was then extended to 60 feet and the augers were left in the boring overnight, pending laboratory analysis of the water sample The boring was completed as groundwater monitoring well VM-3 the following morning, as described below The third boring was drilled to 60 feet and completed as monitoring well VM-2 V & W experienced considerable difficulty with the well completion, and were able to seat the casing and install the sand pack only after three attempts As a result, several feet of silt entered the casing and reduced the depth of the well to 55 feet The silt had to be removed, which V & W did on July 10 by surging and bailing the well 2