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3.0 RESULTS OF THE INVESTIGATION 3.1 Geology and Hydrogeology Soils observed to the total drilling depth of 105 feet mostly consisted of massive clay and silt soils, interrupted by relatively thin and discontinuous sand intervals up to five feet thick. Based on the CPT interpretation, the most significant sandy intervals are between approximately 56 and 60 feet bgs and 99 and 104 feet bgs. Detailed soil descriptions are included on the monitoring well logs (Appendix B), and the CPT interpretation is included in Appendix E. During the drilling of the monitoring well borings between May 30 and June 1, 2007, saturated soils were first observed between 43 and 47 feet bgs. On June 27, 2007, the static depth to the groundwater table, as measured in all eight groundwater monitoring wells, ranged from 39,31 feet bgs in MW-5 to 43,45 feet bgs in MW-4. As such, groundwater appears to be present beneath the site under partially confined conditions. During purging, groundwater recharge appeared to be moderately strong. The groundwater surface elevations in the eight monitoring wells ranged from a high of 17.64 feet below mean sea level (msI) in well MW-5 to a low of 19.47 feet below msl at MW-4. The resulting groundwater surface appears as an irregular plane generally dipping toward the east-northeast at a gradient of approximately 0,0015 foot/foot, A groundwater surface contour map is included as Figure 3, and the well construction details, wellhead elevations and groundwater monitoring data are summarized in Table 5. 3.2 Analytical Results In soil, only the samples collected at 45 feet bgs from the borings for MW-6 and MW-7 contained concentrations of petroleum hydrocarbons above laboratory reporting limits. These two samples both only contained benzene at concentrations ranging from 0.005 to 0.018 milligrams per kilogram (mg/kg). No petroleum hydrocarbon compounds were detected above laboratory reporting limits for the other 14 soil samples analyzed. The soil sample analytical results are summarized in Table 3, and the laboratory reports are included in Appendix G.