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3) During the most recent groundwater sampling event (July 8, •- 1994) ; only -wells MW=9- to --13 contained -suf f icient--water-- for-- - -- sampling (see attached Groundwater Analytical Data - Table 1) . MW- 14 and MW-2R contained sufficient water for sampling in April 1994, but were dry during the July 1994 sampling event. Dissolved benzene was absent from all sampled wells during the July 1994 sampling. The dissolved BTEX and TPH-G values for the five wells containing water in July 1994 are follows: B T E X TPH-G (ppb) MW-9 ND 3 .2 ND ND 80 (7/8/94) MW-10 ND ND ND ND ND (7/8/94) MW-11 ND 2 .6 ND ND ND (7/8/94) MW-12 ND 2 . 6 ND ND 70 (7/8/94) MW-13 ND ND ND ND ND (7/8/94) MW-14 ND 0.5 ND ND 60 (4/6/94) MW--2R ND ND ND ND ND (4/6/94) 4) Remediation activity has consisted of soil vapor extraction from wells V-1 to -5, and MW-3 to -6 (see attached Site Map/VES Wells - Figure 3) . The system was in operation from November 1990 to November 1992, with a seven month hiatus from February 1992 to September 1992. Confirmation soil borings were installed an December 1993 (SB-1 to -3) and May 1994 (SB-4 to -9) . The vacuum radius of influence was estimated to be in excess of 25 feet, for the operational VES present in wells V-1 to V--5 (May 12 , �• 1989 EA report) . The basis of the estimation was not provided, and there was no pilot test data present in the report. Vacuum extraction wells V-1 to V-5 are screened across the interval 15 to 34 feet BGL. A subsequent vacuum radius of influence analysis was conducted on vapor extraction well MW-4, resulting in an estimated effective radius of 112 feet (March 25, 1991 EA report) . The radial influence determination was based on the measured and inferred distance from MW-4 where the resulting vacuum exceeds 0.05 inches of water. The accuracy of this radial influence determination is uncertain, based on the absence of the actual vacuum/distance measurement and applied vacuum data. The relationship of the applied vacuum to the measured vacuum/distance should be known to accurately assess the radial extent of an operating VES. 5) The most highly impacted soil found on-site was localized in the northeast quarter of the former tank pit, and immediately south of the former pump island, generally within a depth interval of approximately 16 to 31 feet BGL. Elevated concentrations of soil hydrocarbons were measured in V-3 (16.5 to 31 feet BGL) , V-5 (26. 5 feet BGL) , MW-4 (31 feet BGL) , MW-9 (21 to 26 feet BGL) and VW-6 (28 feet BGL) (see attached Site Map - Figure 2, and Soil • Analytical Data Tables) . � 2