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19 June 2000 AGE-NC Project No 96-0232 Page 13 of 35 During the first stage of the pump test (pump rate at 4 3 GPM), ground water was drawn below the pressure transducer in MW-1 after 19 minutes ofpumping operation,no measurable draw-down was observed from wells MW-2 (located 120 feet towards the east),MW-4(located 95 feet towards the north) or MW-6A (located 75 feet towards the south) during the first stage of the pump test A transmissiv>ty value from well MW-1 was calculated at 135 gal/day-ft During the second stage of the pump test (pump rate at 3 5 GPM), the greatest ground water draw- down was observed at 6 91 feet after 11 minutes of pumping operation, due to an equipment malfunction,the test was terminated after 11 minutes of operation No measurable draw-down was observed from wells MW-2, MW-4 or MW-6A during the second stage of the pump test A transmissivrty value from well MW-1 was calculated at 349 gal/day-ft During the third stage of the pump test(pump rate at 3 GPM),the greatest ground water draw-down was observed at 4 42 feet after 125 minutes of pumping operation,due to an equipment malfunction, the test was terminated after 125 minutes of operation No measurable draw-down was observed from wells MW-2,MW-4 or MW-6A during the third stage of the pump test A transmissivlty value from well MW-1 was calculated at 932 gal/day-ft Pump test results are summarized in Table 10 6.0. ASSESSMENT OF HYDROCARBON-IMPACTED SOIL Between July 1996 and May 2000, soil sampling was performed at thirty-five soil borings (PI through P35) and twelve ground water monitoring wells (MW-1, MW-2, MW-4 through MW-12) as part of a subsurface petroleum hydrocarbon investigation The greatest MTBE-impacted soil was encountered at soil borings P1-35 feet bsg (0 14 mg/kg), P20-20 feet bsg (0 35 mg/kg), P22-15 feet bsg (0 63 mg/kg), P31-10 feet bsg (0 54 mg/kg) and P34-10 feet bsg (0 72 mg/kg) Soil boring P1 Is located at the southwest corner of the site, P20 is located near the southwest storm dram, P22 Is located near the storm drain discharge pipe system, P31 Is located near the southeast fuel dispenser and P34 is located near the northeast fuel dispenser (Figure 2) TPH-g and TPH-d were detected from P31-10 feet at concentrations of 3 2 and 2 2 mg/kg, respectively,BTEX compounds were detected from P31-10 at concentrations as high as 0 26 mg/kg TBA was detected in soil samples collected at P31-10 feet and P34-10 feet at concentrations of 0 071 and 0 120 mg/kg, respectively Adsanced GcoEnNironmental,Inc