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On 22 May 2000, a total of seven on-site soil borings were established by Hydro-Geo Consultants Inc with a Geoprobe sampling ng Borings A,B and C were established on the northeast corner of the site and borings D through G were established on the west and southern edge of the former service station location,to a depth of 45 feet below surface grade(bsg) Based on laboratory analysis • Total petroleum hydrocarbons as gasoline and diesel (TPH-g and TPH-d) were detected in soil samples collected during boring operations at concentrations as high as 300 milligrams per kilogram(mg/kg) and 2,400 mg/kg, respectively, in the sample from boring A at 30 feet bsg BTEX compounds were detected in the soil samples at maximum concentrations of 0 5 mg/kg(toluene), 1 5 mg/kg(ethylbenzene)and 30 mg/kg(xylenes)in the sample from boring A at 40 feet bsg • TPH-g and TPH-d were detected in grab ground water samples collected during the soil boring operations at concentrations as high as 470,000 micrograms per liter (µg/1) and 230,000 gg/l,respectively,in the sample from boring A Dissolved BTEX compounds were detected at maximum concentrations of 1,900 µg/1 benzene, 4,100 µg/1 toluene and 3,600 pg/l mg/kg ethylbenzene in sample A and 35,000 µg/l xylenes in sample B On 31 Ianuary 2002,three additional soil probe borings were advanced,two borings were advanced on-site to a depth of 90 feet bsg (I and J), while boring H was established off-site across California Street to a depth of 50 feet bsg Laboratory analysis indicated • TPH-g and TPH-d were detected in grab ground water samples collected during the soil boring operations at concentrations as high as 120,000pg/l and 190 µg/1,respectively,in the sample from boring J at a depth of between 46 and 50 feet bsg Dissolved BTEX compounas were detected at maximum concentrations of 650 µg/l benzene in sample I at a depth of between 46 and 50 feet bsg and 9,000µg/1 toluene,2,900µg/l mg/kg ethylbenzene and 9,000 pig/l xylenes in sample J at a depth of between 46 and 50 feet bsg On 02 August 2001, three ground water monitoring wells (MW-1, MW-2 and MW-3), screened between 20 and 40 feet bsg, were installed at the site (Figure 2) Well MW-1 was installed at the northeast corner of the site, and wells MW-2 and MW-3 were installed at the southern edge of the dissolved plume area Two ground water monitoring events have occurred to date, the last one in January 2002 • Ground water elevation at the site is approximately 15 feet below mean sea level Ground water at the site is inferred to flow north-northeast • TPH-g,TPH-d and BTEX compounds have not been detected in ground water samples from wells MW-2 and MW-3 • TPH-g and TPH-d have been detected in well MW-1, the highest concentrations were detected during the January 2002 monitoring event at 18,000 µg/1 and 9,000 µg/l, respectively Advanced GeoEnvironmental