SITE INFORMATION AND CORRESPONDENCE_FILE 2

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15 May 2009 AGE-NC Project No. 95-0103 Page 5 of 6 remediated by air-sparging as documented by soil sample collected in 1999. These samples demonstrate the remediation of the soil by approximately 90%(attached tables). The same paragraph contains the EHD conjecture of Chapin Petition assertion that rate of the reduction of adsorbed mass has not been established. The amount of remediation can be evaluated based on the comparison of soil sampled collected near the source area prior to ground water extraction and following the first ground water extraction cycle(2001-2005).Soil samples from CB5 and EW-5 demonstrate the remediation of the soil by approximately 90% (attached tables). Additionally, extraction well EW-4 was remediated, which is the location for 8,000-gallon UST release area. Following several month of ground water remediation the well was generally remediated. Additionally, a five-day Duel Phase Extraction pilot test was conducted on well EW-4 and the results indicated no significant mass was extractable from the former 8,000-gallon UST release area. The same paragraph contains the EHD conjecture of Chapin Petition assertion that shallow ground water contamination was present,presumable on-site,when the site is not under active remediation. The EHD states the shallow ground water is potential route of exposure to petroleum hydrocarbons. Off-site ground water contamination was not present east of the site at well MW-7, nor at near the school boundary 130 feet northwest(building location is 1500 from site),nor at well MW-2 north of the site,southeast of the site at borings B9,B 12,B 13 and CHP8 nor south at CHP9.Ground water impact was detected west at well MW-5 (vacant lot)and at well MW-3 (parking lot);however,the off-site ground water contamination was not present in borings B 11,CHP2,CHP3 and CHP7. The dissolved ground water plume does not appear to threaten off-site structures, following the active site remediation(s). AGE recommended the performance of a soil vapor survey in the second quarter 2007 and provided technical justifications. However, in the letter the EHD dated 26 July 2007 stated"At this time the EHD does not concur with the recommendations for additional site assessment or collection ofsoil gas samples from beneath the structures on site as a technical justification was not provided for either"and"If such data is needed to fulfil the directives currently in effect the site specific need(s) should be noted". AGE and Chapin are aware of soil and ground water contamination on the site, from former USTs and dispensers. This fact alone was justification for authorizing a soil vapor survey,possible for on-site indoor air migration(auto repair garage).Now,the EHD has stated this ground water contamination is a threat or a requirement for soil vapor sampling was enforce without a justification. Although the ATC Associates,Inc,(ATC)Closure Summary Report was not acceptable to the EHD based on technical deficiencies to demonstrate the site a candidate for closure, the basis of the arguments within the Closure Summary Report still hold. Advanced GeoEnoironmental,Inc.