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12 August 2002 AGE-NC Project No. 99-0645 Page 2 of 8 advanced at a 20 degree angle fi-om vertical, oriented west under the building on the site and north under the neighboring property,respectively. The highest concentrations of-petroleum hydrocarbons were encountered in the borings at a depth of 15 bsg, with reduced concentrations encountered at depths to 70 feet bsg. A stratigraphic cross section is depicted in Figure 3 and impacted soil is depicted in Figure 3A. Based on three quarterly ground water monitoring results to date,ground water was inferred to have a northeasterly flow direction. In the November 2001 quarterly ground water monitoring event, MTBE was detected in sample MVV-1, collected within the former UST location. In the April 2002 ground water monitoring samples, TPH-g was detected at 120 micrograms per liter (Vg/1) and 130 µg/l in well MW-1 and MW-2, respectively; BTEX compounds, MTBE and the remaining fuel additives were not detected; TPI 1-d was detected at 55 Iig/l in well MW-1. Additional site history and findings fi-om previous site investigations are detailed in the AGE-prepared Evacuation and Sumplin.g Report, dated 05 September 2000 and Prelitninan, Investigation and Evaluation Report, dated 07 March 2002. 3.0. SCOPE OF WORK In order to assess the lateral extent of exceptionally MTBE-impacted soil detected at the former UST area at a depths to of 60 feet bsg, AGE proposes to install two additional soil borings, one vertical boring located at the eastern edge of the site, and one slanted boring at the northern edge. drilled at an angle similar to soil boring B6 (Figure 2). In order to evaluate the feasibility of SVE remediation at the site, AGE proposes to install three shallow soil vapor wells within a thick upper sand layer and three deep soil vapor wells in underlying fine-grained soil, and conduct 8-hour SVE pilot tests for shallow and deep wells. The proposed scope of work will include the following tasks: • Pre-field work activities: • Installation of soil borings and remediation wells; • Analysis of soil samples; • Performance of SVE pilot test; • Sampling and analysis of pilot test samples and • Report preparation. Advanred Geo Env iron mental,Inc.