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a ' 25 February 2005 AGE-NC Project No 95-0104 ' Page 2 of 10 ' soil sample MW4-45 at 0 43 micrograms per gram (µg/g) On 04 April 1995, soil vapor extraction well VW-1 was Installed at the site near the center of the former UST TPH-g was detected in sample VW1-25 at a concentration of 14,000 milligrams per kilogram (mg/kg) In December 1996, two additional monitoring wells (MW-5 and MW-6) were Installed down-gradient or east and southeast of the former UST area Laboratory analysis of soil samples did not detect any petroleum hydrocarbons IBased on ten years of quarterly monitoring, the depth to ground water has ranged between approximately 52 27 feet and 82 5 8 feet bsg(Table 1)at the site,and has consistently had a northeast flow direction, with the exception of the past two quarterly monitoring events Analytical results of soil and ground water samples collected from the site during the previous investigations are presented in Tables 2 and 3 The current distribution ofthel,2-DCA dissolved in the ground water at the site (Figures 3 through 6) 1 12 Soil and Ground Water Remediation Activities Between 18 March and 16 April 1999, a soil vapor extraction (SVE) pilot test was initiated at the site by applying a vacuum at well VW-1 The volume of hydrocarbons extracted from VW-1 between 18 March and 16 April 1999 was calculated to be approximately 81 gallons of petroleum hydrocarbons Between 22 July and 14 December 1999, a SVE pilot test was continued at the site The volume of hydrocarbons extracted from VW-1 between 22 July 1999 and 14 December 1999 was calculated to be approximately 77 92 gallons of petroleum hydrocarbons AGE estimated that operation of the SVE system has removed approximately 158 92 gallons to date, or approximately 53 percent of petroleum hydrocarbons formerly impacting soil at the site An IAS pilot test was also conducted by connecting an air compressor to the well-head at MW-6 Compressed air was supplied to well MW-6 at an approximate pressure of 10 pounds per square inch (psi) Approximately 5 to 7 psi was required to overcome the water column in the sparging wells Air sparing continued until the end of the SVE pilot test in December 1999 On 14 July 2000, one conformational soil probe boring(P-1)was advanced at the site to assess the I effectiveness of SVE remediation effort at the site TPH-d was detected in four of the soil samples collected from probe boring P-1 at concentrations as high as 410 mg/kg (P 1-25) TPH-d was not detected in soil samples collected from depths of 35 and 40 feet bsg however,the 45-foot soil sample contained TPH-d at a concentration of 1 8 mg/kg TPH-g and BTEX compounds were not detected • in any of the soil samples analyzed The only soil samples collected from the site that have been IAdvanced GeoEnvironmental,Inc