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• r gasoline (TPH-g)was reported in the soil samples collected from pilot soil borings MWI (19 feet bsg) and MW4 (10 feet bsg, 15 feet bsg and 19 feet bsg) at maximum concentrations of 720 mg/kg. • In 1997, a limited sensitive receptor survey was performed. Three domestic and private wells were observed within 2,000 feet of the site. Each well was reported to be constructed with a 50-foot bentonite seal; backfill material classified as pea gravel; and as surface well seal. The casing depths for the three wells ranged from 160 to 220 feet below surface grade. The closest well was located approximately 350 feet to the southeast of the site. • On 29 July 1999, a total of six soil probe borings (P6 through P11) were advanced at the site and off-site to the north, east and northwest of the former UST location. TPH-d was reported in all five of the grab ground water samples collected from probe borings P6 through P9 and P11 at concentrations ranging from 430 µg/l (P11) to 1,100 pg/l (P7). TPH-g and BTEX compounds were not reported in the ground water samples collected from probe borings P6 through P9 and P11. TPH-g was reported in soil samples collected from probe boring P10 at 15 feet, 20 feet and 25 feet at decreasing concentrations of 350 mg/kg, 160 mg/kg and 14 mg/kg, respectively. • On 26 October 2001, a total of four soil probe borings (P 12A, P 12B, P 13A and P 13AB) were advanced at the site to the south and near the former UST location to collect depth- discrete water samples at 40 feet bsg (P12A and P13A) and 50 feet bsg (P12B and P13B). TPH-d was detected in each of the four of the grab ground water samples at concentrations ranging from 130 ggll (P12B)to 550 gg/l (P13A). • On 28 and 29 October 2002, monitoring well MW-5 and six ozone sparge wells (0SP1A, OSP1B, OSP2A, OSP2B, OSP3A and OPS3B)were installed. A total of three soil samples were collected from the pilot boring MWS at 20 feet bsg, 25 feet bsg and 30 feet bsg. No constituents of concern were reported in the soil samples collected from the pilot boring MW5. • Between June 1996 and November 2006, twenty-eight ground water monitoring and sampling events were performed at the site to monitor dissolved petroleum hydrocarbon concentrations in ground water and to characterize ground water flow direction and gradient at the site. During this time period, the maximum concentrations of hydrocarbon impact in ground water was reported for TPH-d at 1,500,000 p.g/l in monitoring well MW-4 in May 2005; TPH-g at 270,000 µg/1 (diesel range) in monitoring well MW-4 in May 2005; benzene at 34 µg/l in probe boring P4 in December 1996; toluene at 11 µg11 in offsite monitoring well MW-1 in June 1999; ethyl-benzene at 3.5 µg/l in monitoring well MW-4 in June 2002; and total xylenes at 54 gg/l in monitoring well MW-4 in June 1996. • In August 2006, a set (3 in each set) of crash poles were placed around wells MW-2 through MW-4 as a protective barrier against damage from ongoing construction activity at the site. Advanced GeoEnvironmental,Inc.