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not detected in soil samples collected at a depth of 30 feet or 35 feet bsg. TPH-d was detected in soil samples collected from a depths of 15, 20 and 25 feet bsg at concentrations ' of 5,100 mg/kg, 13,000 mg/kg and 490 mg/kg,respectively. TPH-d was not detected in soil collected at a depth of 30 feet bsg or below (Tables 1 and 2).' • On 26 October 2001,a total of four soil probe borings(PI2A/B and P13A/B)were advanced ' at the site south of the and near the former UST location.Probe borings were advanced in the area of the former USTs to collected depth discrete water samples. TPH-d was detected in all four of the grab ground water samples analyzed at concentrations from 130 micrograms ' per.liter(µg11) to 550 µg/1 (Table 2). ' On 28 and 29 October 2002, monitoring well MW-5 and six ozone sparge wells (OPS IA through OPS3B) were installed. A total of three soil samples-were collected from MW-5 and analyzed for TPH-g, TPH-d, BTEX and fuel additives. None of the target.compounds were detected in the soil ' samples analyzed. Between June 1996 and February 2003, 20 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 on the site (Table 3). ' During the most recent sampling event: TPH-d was detected in ground water samples collected from ground water samples MW-1 and MW-4 at concentrations of 20,000µg11 and ' 93,000 µg11, respectively. TPH-g was detected in samples MW-1 and MW-4 at concentrations of 1,400 µg11 and 6,700 gg/l,respectively.In addition,the BTEX compounds ethylbcnzene,toluene and total xylenes were detected in sample MW-4'at concentrations of ' 1.8 µg/l, 2.1 µg/1 and 8.4 µg/ljespectively. • Ground elevations have increased approximately 0.8 feet during the monitoring period. ' The lateral extent of the dissolved petroleum hydrocarbon plume is delineated by the current area bound by wells MW-1 through MW-5 and soil borings: GROUND WATER DEPTH AND FLOW DIRECTION ' In February 2003, ground water depth was measured at approximately 24 feet below surface grade (bsg). Review of historical AGE depth to ground water measurements indicates that ground water ' depth near the site has fluctuated between approximately-15 and 20 feet bsg. Ground water flow direction at the site can vary seasonally. However,the overall regional flow direction is southwest. ' Advanced GeoEnvironmental,Inc. . I