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• Soils observed during the drilling of the three monitoring well borings to a maximum depth of 87 ' feet bgs consisted mostly of massive intervals of clay, silt and fine sand mixtures interrupted by thin (i e, less than five feet thick) intervals of poorly-graded fine sand Laterally continuous sand sequences were observed at approximately 15 feet bgs and at 75 to 80 feet bgs Other sand intervals were observed as laterally discontinuous across the site ' During drilling, saturated soil and groundwater were first encountered between 79 5 and 80 1 feet bgs One week later, the static depth to the groundwater table, as measured in the three groundwater monitoring wells, ranged from 77 40 feet bgs in MWA to 78 23 feet bgs in MW-3 As such, groundwater does not appear to present under significant confining conditions The groundwater surface elevation ranged from a high of 22 64 feet (arbitrary datum) at MW-2 to a low of 22 42 feet (arbitrary datum) at MWA The resulting groundwater surface appeared as a regular plane dipping to the north-northeast at a gradient of approximately 0 0037 foot/foot The monitoring well construction details and groundwater monitoring data are summarized in Table 1 The 12 soil samples, three monitoring well groundwater samples, and the domestic water supply well sample collected during the investigation did not contain detectable concentrations of any of the gasoline constituent compounds analyzed The groundwater sample analytical data are summarized in Table 2 On February 1, 2002, Ramage Environmental published Monitonng Well Installation and Groundwater Monitonng Report, which documented the installation of one monitoring well (MW-4) northeast of the gasoline UST system This additional well confirmed the north-northeast ' groundwater flow direction The groundwater sample collected from this well only contained 0 55 µg11 of xylenes Groundwater samples collected from the other three monitoring wells and the on- site water supply well did not contain detectable concentrations of any gasoline compounds 1 2 4 Sensitive Receptor Surve To evaluate possible health and safety impacts from gasoline constituent compounds in soil and groundwater beneath the site, Ramage Environmental surveyed potential sensitive receptors within 2,000-feet of the site (site vicinity) The survey included a review of water well completion reports at the California Department of Water Resources (DWR) and a tour of the site vicinity The results of the survey are documented in Ramage Environmental's Sensitive Receptor Survey and Groundwater Monitonng Report, First Quarter 2001, dated June 8, 2001 1 7 1