ARCHIVED REPORTS_QUARTERLY REPORT - THIRD QUARTER 2003

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' contamination was concentrated near the surface and diminished as depth increased. The • estimated size of the proposed excavation area was+/- 20' X 30'to a depth of+/- 8', with a ' volume of+/-200 cubic yards. The removed soil would be stockpiled on site until removed to a regulated landfill or was reclaimed on site. • On 04 January 1999, FE issued a memo to the EHD on the analysis of three samples taken ' during over-excavation of the pump area. FE assumed that contamination would be found under the pump island and to the east of the excavation area. Samples BS-2 and side sample ' SW-1 from the west side of the excavation showed discoloration and FE determined that it might be from the pre-1986 fueling operations. FE interpreted the data to show that contamination may extend deeper than suspected and recommended that a work plan be ' developed to assess the horizontal and vertical extent of contamination and that the work plan should include ground water sampling under the fuel islands. • In September 1999, three shallow ground water monitoring wells were installed near the ' former western fuel dispensing island, surveyed and later sampled. Dissolved petroleum hydrocarbons were detected in ground water samples from each of the ground water wells. ' • In September 2000, three shallow and four depth-discrete ground water monitoring wells were installed and sampled.Hydrocarbon-impacted soil was encountered from 20 feet to 70 feet below surface grade(bsg)in the soil boring established within the former UST product ' line trench area(MW-5);significant concentrations of BTEX compounds were detected from 35 feet to 65 feet bsg in the soil from this area. Ground water samples from the former UST and western dispenser areas had detectable concentrations of dissolved hydrocarbons. ' • A total of ten ground water observation wells have been installed and monitored as part of the UST site investigation.The lateral extent of the dissolved hydrocarbons has been defined ' to the east and south by the well network. ' PREVIOUS SITE ASSESSMENT ' In November 1998, AGE conducted a site visit/reconnaissance of the property as part of a Phase I site assessment for a potential property transfer/assessment; there were no regulatory directives in effect for the property at that time. AGE identified several general areas of potential environmental ' concern, which included a motor oil storage or waste oil transfer area indicated by the previously mentioned above-ground storage tank and two circular depressions on the western edge of the building on the site. The subsequent site-investigation activities included soil borings in 1999,cone ' penetrometer tests (CPTs) in 2000 and ground water monitoring wells installation in 2001. 1 • ' Advanced GeoEnvironmental,Inc.