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composed of clayey sand, sand, silt, silty clay and fill In the former gasoline UST pit, fill ' materials appear to extend from the ground surface to between 8 to 10 feet bgs Site Hydrogeology ' The depth to groundwater beneath the site was recorded at 4 07 to 4 63 feet bgs on January 8, 1996 In order to determine groundwater gradient on-site, the top of casing (TOC) elevations of ' the wells were surveyed relative to each other on January 8, 1996 The TOC elevations were used to evaluate groundwater flow direction on January 8, 1996 The evaluated groundwater flow direction was to the northwest with a hydraulic gradient of 0 002 ft/ft as shown on Figure 3 The ' flow direction and gradient may be subject to seasonal fluctuations ' Because the evaluated groundwater flow direction on January 8, 1996 was towards the northwest and not the anticipated northeast direction, the TOC elevations of the wells were resurveyed for accuracy on January 25, 1996 and found to be true ' Analytical Results- Soil ' The results of laboratory analyses of soil samples collected from the bonngs indicate that petroleum constituents were detected to the shallow samples collected from bonngs MW-3 and ' SB-3 Petroleum constituents were not detected above method detection linuts in the deeper samples collected from bonngs MW-3 and SB-3, or in the samples collected from borings MW-1, ' MW-2, SB-1, and SB-2 However, lead was detected to all the samples at concentrations within typical soil background concentrations (USGS, 1992) TPHg was detected at a concentration of 1 1,900 parts per million (ppm) and BTEX compounds were detected above the method detection ' lirruts in boring SB-3 at 6 feet bgs TPHmo was detected at a concentration of 270 ppm in boring MW-3 at 4 feet bgs Analytical results are shown in Table 1 A copy of the laboratory report and chains of custody are presented in Appendix IV w W511"SA as 5 1 SMTN