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1 <br /> 4.0 SUBSURFACE CONDITIONS <br /> Soils encountered beneath the project site consist primarily of silt (ML) to approximately 8 to <br /> 11 feet below grade, and poorly graded sand with silt (SP-SM) to well graded sand (SW) from <br /> approximately 8-31 feet below grade, the maximum depth explored. Stratigraphic cross-section <br /> orientations are shown on Figure 4 Site stratigraphy is shown on Figures 5 and 6 <br /> Slight to moderate product odors were noted in Soil Borings MW3 and MW4 Relatively high <br /> concentrations of hydrocarbons were detected in these borings. Slight product odors were noted <br /> in MWS. No product odors were noted in Borings MW1, MW2, or MW6 <br /> Groundwater was encountered at approximately 11 to 16 feet below grade Groundwater flows <br /> ' generally west/southwest under a gradient of approximately 0 0017 or 9 ft/mile, as depicted on <br /> Figure 7. <br /> 5.0 CONCLUSIONS <br /> 5.1 Soil Contamination <br /> Field PID readings and laboratory results of soil samples collected from Bonngs MW3 and <br /> ' MW4 indicate moderate to high levels of hydrocarbon constituents exist in the soil in the vicinity <br /> of these wells. Field PID measurements and laboratory results of soil samples collected from <br /> Borings MW1, MW2, MWS, and MW6 detected none to low levels of hydrocarbons in the soil <br /> suggesting soil contamination is limited to a small area in the immediate vicinity of the former <br /> tanks, and near the municipal well enclosure It is unclear if the soil contamination at MW3 <br /> (near the former tanks) and MW4 were derived from the same source <br /> 5.2 Groundwater Contamination <br /> Analytical results of groundwater samples collected from MW3 and MW4 indicate that <br /> groundwater has been impacted beneath the site The lateral extent of the dissolved hydrocarbon <br /> ' plume associated with the former fuel storage tanks has been identified to the west <br /> (downgradient), south, and east The northern extent of the plume has not yet been defined <br /> Although laboratory results indicate that MW4 (north of the former tanks) contains dissolved <br /> hydrocarbon constituents, the configuration of the groundwater flow beneath the site suggests <br /> GPR1227 7PL 6 <br />