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S%Wl- Soil and groundwater beneath the northwest side of the former USTs were impacted by petroleum hydrocarbons. The soil sample analytical results are summarized in Table 3, and the groundwater analytical results are summarized in Table 4. 1-2 3 Mouitonn�Well ell Installations On January 9, 2003, Ramage Environmental published Monitoring Well Installation Repott, which documented the installation, survey, and initial sampling of three groundwater table monitoring wells (MW-1, MW-2 and MW-3). The well locations are shown on Figure 2. Soils to the total drilling depth of 65 feet mostly consisted of massive clay and silt soils, and relatively thin and discontinuous sand intervals less than five feet thick. During drilling, saturated soil was first observed at approximately 56 to 57 feet bgs, and the static depth to the groundwater table, ranged from 46.28 to 46.72 feet bgs, As such, groundwater appeared to be present under semi-confined conditions. The groundwater potentiornetri c surface appeared as a regular plane dipping to the north. In soil, 3 of the 15 samples analyzed contained concentrations of petroleum hydrocarbons above laboratory reporting limits. The highest concentrations were observed between 45 and 55 feet within the capillary fringe and zone of groundwater fluctuation. Laterally, the extent of impacted A&W soil appeared to be limited to beneath the former LISTS. Vertically, the extent of impacted soil appeared to be defined. The soil sample analytical results are summarized in Table 3. The groundwater samples collected from all three monitoring wells contained concentrations of petroleum hydrocarbons above laboratory reporting limits. The highest concentrations were detected at MW-1, which contained 840 micrograms per liter( g/1) of Total Petroleum Hydrocarbons (TP H)-as-jet fuel, 7,700 ug/l of TPP— -gasoline, 1,300 pg/l of benzene, 460 itg/l of toluene, 490 j.tg/l of ethylbenzene, and 670 g/l of xylenes. The lateral extent of impacted groundwater was not defined. The groundwater analytical results are summarized in Table 4. 1-2.4 Additional�Sitq 1hvesti�ation On August 3, 2007, Ramage Environmental published Additional Site Investigation Report, which documented the installation of five additional groundwater table monitoring wells (MW-4, MW-5, MW-6, MW-7 and MW-8), and depth-discrete soil and groundwater sampling from below the groundwater table at one cone penetration test (CPT) location (CPT-1). The monitoring well and CPT locations are shown on Figure 2. 4