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s e l4ti groundwater monitoring data (March 1992) determined groundwater flow direction to the south. A detailed discussion of the initial subsurface investigation can be found in RESNA's "Intenm Problem Assessment Report, Soil and Groundwater Contamination, ' dated June 8, 1992. In July 1994, a RESNA field geologist observed the drilling of four additional groundwater monitoring wells (MW4, MW5, MW6, and MW7) at the site to further characterize subsurface conditions Groundwater samples collected from these additional wells contained no detectable petroleum hydrocarbons. A detained discussion of the Phase 2 Subsurface Investigation can be found in RESNA's "Summary Report, July 1994 Investigation, " dated August 26, 1994. In a letter received from the PHS/EHO dated March 1995, permission was given to sample wells MW3 and MW5 and wells MW4, MW6 and MW7 on an alternating semi-annual basis Wells MW 1 and MW2 were to be sampled every quarter, conditions permitting Prior to the fourth quarter groundwater monitoring and sampling, a product sample was collected from monitoring well MW-2 on November 13, 1995. SOIL SAMPLING • To further define the extent of soil contamination near the former contaminant source the former underground fuel storage tank (UST), Srruth Environmental supervised the advancement of four soil borings (SB-1, SB-2, SB-3, and SB-4) on February 29, 1996 to depths of approximately 16 to 26 feet below ground surface (bgs) in locations upgradient (SB-2), crossgradient (SB-1 and SB-4), and downgradient (SB-3) from the former UST TPHg and BTEX were detected above method detection limits at low to moderate concentrations in samples collected at depths between 10 and 15 feet bgs in borings SB-1, SB-2, and SB-3 A detailed discussion of this subsurface investigation can be found in Smith Environmental's draft "Subsurface Investigation Report, " dated March 28, 1996 GRQUNDWATER MONITORING AND SAMPLING Smith Environmental personnel performed groundwater monitoring and sampling on Apnl 12, 1996 Field work included measuring the depth-to-water in wells MW1, MW2, MW3, MW4, MW5, MW6, and MW7; using an electronic water/product interface probe to determine if free product was present; purging and sampling wells MW1, MW2, MW4, MW6, and MW7, and subjectively evaluating collected water samples for the presence of petroleum hydrocarbon constituents. Static groundwater elevations were measured in each monitoring well on April 12, 1996. • Groundwater exists at approximately 11 to 12 feet below grade A groundwater gradient map 9433AQUAA7Lri[QA 1996MOC • SMTH