SITE INFORMATION AND CORRESPONDENCE_FILE 2

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Site Background Information: Chapin Brothers Investments, Inc. Page 11 of 19 respectively;TBA was detected in samples collected from wells MW-1,MW-3,MW-5 and vapor well VE-1 at concentrations of 18 µg/1, 16 µg/1, 11 µg/1 and 56 µg/1,respectively. • ETBE and TAME were not detected in samples collected from the site. • Figure#depicts an approximate areal distribution of ground water containing benzene. A reduction of hydrocarbon concentrations in soil samples collected from both on-site and off-site is depicted in Table#.Benzene was not detected in any of the soil samples analyzed and in general TPH-g has been reduced, while three soil sample sets had an apparent increase of TPH-g concentration.Benzene concentrations in soil samples analyzed prior to remediation did not exceed 33 mg/kg(on-site). Benzene was not detected in soil samples collected from off site locations. The highest concentration of benzene was detected in the sample collected from monitoring well MW-4 at 740 µg/1. Benzene was also detected in four of the conformation grab water samples collected from the site at a maximum concentration of 150 gg/1 (CHP5). Benzene was detected in samples collected from grab water sample CHP6 and CB3 at concentrations of 1.2µg/1 and 2.8 gg/l. The lack of detection of benzene in sample CHP 1,CHP2,CHP3,CHP7,CHP8 and CHP 9 limit the petroleum release to the areas under the building,the north and western ends of the site and an area extending 140 feet west of the site. A reduction of the dissolved-phase hydrocarbon plume concentrations on the site has occurred.The current concentrations of benzene in samples MW-1 and MW-4 are less than 0.02 % and 1.6 %, respectively, of the highest concentrations of benzene detected in samples collected from the monitoring wells. Advanced GeoEn%ironmental,Inc.