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Soils observed during the drilling of the three monitoring well borings to a maximum depth of 87 <br /> ' feet bgs consisted mostly of massive intervals of clay, silt and fine sand mixtures interrupted by <br /> thin (i e, less than five feet thick) intervals of poorly-graded fine sand Laterally continuous sand <br /> ' sequences were observed at approximately 15 feet bgs and at 75 to 80 feet bgs Other sand <br /> intervals were observed as laterally discontinuous across the site <br /> ' During drilling, saturated soil and groundwater were first encountered between 79 5 and 80 1 feet <br /> bgs One week later, the static depth to the groundwater table, as measured in the three <br /> ' groundwater monitoring wells, ranged from 77 40 feet bgs in MW-1 to 78 23 feet bgs in MW-3 As <br /> such, groundwater did not appear to present under significant confining conditions <br /> ' The groundwater surface elevation ranged from a high of 22 64 feet (arbitrary datum) at MW-2 to <br /> a low of 22 42 feet (arbitrary datum) at MW-1 The resulting groundwater surface appeared as a <br /> regular plane dipping to the north-northeast at a gradient of approximately 0 0037 foot/foot The <br /> monitoring well construction details and groundwater monitoring data are summarized in Table 2 <br /> ' The 12 sod samples, three monitoring well groundwater samples, and the domestic water supply <br /> well sample collected during the investigation did not contain detectable concentrations of any of <br /> the gasoline constituent compounds analyzed The sod sample analytical results are summarized <br /> in Table 1, and the groundwater sample analytical data are summarized in Table 3 <br /> ' On February 1, 2002, Ramage Environmental published Monitoring Well Installation and <br /> Groundwater Monitoring Report, which documented the installation of one additional monitoring <br />' well (MW-4) northeast of the gasoline UST system This additional well confirmed the north- <br /> northeast groundwater flow direction The groundwater sample collected from this well only <br /> contained 0 55 pg/1 of xylenes Groundwater samples collected from the other three monitoring <br /> wells and the on-site water supply well did not contain detectable concentrations of any gasoline <br /> compounds The well location is shown on Figure 2, the soil sample analytical results are <br />' included in Table 1, the well construction details and groundwater monitoring data are included in <br /> Table 2, and the groundwater analytical results are summarized in Table 3 <br /> 8 <br />