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• 3.0 RESULTS OF THE INVESTIGATION 1 31 Geology and Hydrogeology Soils observed to the total drilling depth of 65 feet mostly consisted of massive clay and silt soils, interrupted by relatively thin and discontinuous sand intervals less than five feet thick The ' distribution of sandy soils is shown in a stratigraphic cross-section (Figure 3), and detailed soil descriptions are included on the monitoring well logs (Appendix C) During drilling on October 21 and 22, 2002, saturated soil was first observed in the three monitoring well borings at approximately 56 to 57 feet bgs, and static groundwater was measured at between 46 23 and 47 30 feet bgs On November 26, 2002, the static depth to the groundwater table, as measured in the three completed groundwater monitoring wells, ranged from 46 28 feet bgs in MW-2 to 46 72 feet bgs in MW-3 As such, groundwater appears to be present under semi-confined conditions The corresponding groundwater surface elevations in the three wells ranged from a high of 25 19 feet below mean sea level (msl) at MW-2 to a low of 25 48 feet below msl at MW-3 The resulting groundwater surface appears as a regular plane dipping to the north at a gradient of approximately 0 00157 foot/foot A groundwater surface contour map is included as Figure 4 The well construction details, wellhead elevations and groundwater monitoring data are ' summarized in Table 5 ' 32 Analytical Results Only 3 of the 15 soil samples analyzed contained detectable concentrations of petroleum ' hydrocarbons The sod sample collected at 45 feet from MW-1 contained 25 milligrams per kilogram (mg/kg) of TPH-as het fuel, 1,400 mg/kg of TPH-as-gasoline, 31 mg/kg of benzene, 5 6 ' mg/kg of toluene, 7 0 mg/kg of ethylbenzene, and 15 mg/kg of xylenes The soil sample collected at 55 feet from MW-1 contained 120 mg/kg of TPH-as-gasoline, 3 2 mg/kg of benzene, and 0 56 mg/kg of ethylbenzene The sod sample collected at 20 feet from MW-3 only contained 0 01 mg/kg of ethylbenzene and 0 011 mg/kg of xylenes The five oxygenates were not detected in any of the soil samples The soil sample analytical results are summarized in Table 3, the ' concentrations of gasoline compounds in soil are shown in cross-section (Figure 5), and the laboratory reports are included in Appendix D 10 1 1