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1 <br /> 3.0 FINDINGS <br /> 3.9 Groundwater Level Measurements <br /> Groundwater is present beneath the site at a depth of 32 60, 32 50, 32 49 and 32 05 feet below <br /> top of casing (btc), as measured on 19 September 2001 in the four groundwater monitoring wells <br /> (MW-1, MW-2, MW-3 and MW-4 respectively) installed on site <br /> El utilized the groundwater measurements to determine the direction of groundwater flow and <br /> the groundwater gradient present beneath the surface The groundwater direction of flow for the <br /> Iarea bound by MW-1, MW-2 and MW-4 was inferred to be toward the southeast at a gradient of <br /> 0 0079 ft/ft (Figure 3), groundwater direction of flow in the area bound by MW-1, MW-3 and <br /> MW-4 was inferred to be curving toward the east a gradient of 0 0101 ft/ft <br /> The groundwater elevation at the site decreased an average three (3) feet between June 2001 and <br /> September 2001 The gradient increased slightly during that period <br /> Groundwater elevations are is depicted in Table 1, and graphically in Figure 4 <br /> 3 2 Groundwater Sample Analysis Results <br /> The groundwater was sampled on 19 September 2001 The results, summarized in Table 2, <br /> indicate that TPH-diesel contamination is still present on-site MW-2 shows no change in TPH- <br /> gasohne, oxygenates and BETX contamination, however, analytical results indicate no presence <br /> rof motor oils MW-3 remains free from targeted contamination TPH-gasohne, oxygenates and <br /> BETX contamination are no longer evident in MW-4, however, diesel contamination is now <br /> tpresent The laboratory data sheets and chain-of-custody forms are presented in Appendix B <br /> IAll groundwater samples secured by El were logged in a chain-of-custody form, placed in an on- <br /> site refrigerator and picked up by a California Department of Health Services (DHS) certified <br /> laboratory for analysis for <br /> • Total petroleum hydrocarbons as diesel, oil and gasoline (TPHg, TPHd and TPHo) by <br /> EPA Method 8015 <br /> • Volatile aromatic compounds — benzene, toluene, ethyl benzene and total xylenes <br /> Environeenng,Inc Project No 01-009 012 Page 3 <br />