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CAMBRIA <br /> • Soil assessment performed recently (June 2004) indicates residual petroleum <br /> hydrocarbons are present in soil west and north of the former UST area These data are <br /> shown on Table 1 and Figure 3 The boring Iogs for the recent assessment work are <br /> included in Appendix B <br /> • Based on the current and historical data, Cambria recommends excavating and offhauling <br /> soil in areas of the site west,northwest, and north of the former UST area The proposed <br /> area of excavation is shown on Figure 3 <br /> • The aerial extent of the excavation was chosen base on the approximate Iocation of soil <br /> containing total petroleum hydrocarbons as gasoline (TPHg) concentrations of 1,000 <br /> ppm or greater, at depths of 15 feet or shallower <br /> • We anticipate groundwater will be approximately 11 fbg in the proposed area of <br /> excavation A fine sand (SP) was encountered at depths ranging from 11 to 20 fbg in the <br /> soil borings drilled within the proposed area of excavation We anticipate this sand will <br /> be saturated and unstable below 11 fbg and that digging beyond this depth may not be <br /> • possible However, we will attempt to dig to 15 fbg if soil conditions permit <br /> • Well MW-5 is located within the proposed overexcavation area and will have to be <br /> properly destroyed prior to excavation activities <br /> Work Tasks <br /> Site Safety Plan. Cambria will prepare a Site Safety Plan for overexcavation fieldwork and well <br /> destruction activities <br /> Overexcavation: The arearo osed for overexcavation is shown on Figure 3 This area w <br /> p p g as <br /> chosen based on soil boring analytical data showing the highest levels of TPHg <br /> Based on soil analytical data, overexcavation will be attempted to the depth of 15 fbg However, <br /> the depth of the excavation may be limited to a depth less than 15 fbg due to several factors <br /> These factors included the depth limitations of the excavation equipment used, the stability of the <br /> soil, and whether or not we will be able to keep the excavation dewatered when digging below <br /> the level of groundwater The depth to groundwater in the area of the excavation is expected to <br /> be approximately 11 fbg,based on historical data <br /> 0783 3 <br />