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i 3.0 FINDINGS ' 3.1 Groundwater Level Measurements Groundwater is present beneath the site at a depth of 29 65, 29 95, 29 45 and 29 04 feet below top of casing (btc), as measured on 27 June 2001 in the four groundwater monitoring wells (MW-1, MW-2, MW-3 and MW-4 respectively) installed on site ' El utilized the groundwater measurements to determine the direction of groundwater flow and the groundwater gradient present beneath the site The groundwater direction of flow for the ' area bounded by MW-1, MW-2 and MW-4 was inferred curving southeast at a gradient of 0 0013 ft/ft (Figure 3), groundwater direction of flow in the area of MW-3 was inferred to be ' toward the southeast at a gradient of 0 0035 ft/ft ' The groundwater elevation at the site decreased an average 2 feet between March 2001 and June 2001 The gradient decreased to near zero IGroundwater elevations are depicted in Table 1, and graphically in Figure 4 3.2 Groundwater Sample Analysis Results ' The groundwater was sampled on 27 June 2001 The results, summarized in Table 2, indicate that TPH-diesel contamination is no longer present on-site MW-2 shows no change in motor ' oils, TPH-gasoline, oxygenates and BETX contamination MW-3 remains free from targeted contamination TPH-gasoline, oxygenates and BETX contamination remains consistent in MW- ' 4 The laboratory data sheets and chain-of-custody forms are presented in Appendix B All groundwater samples secured by EI were logged on a chain-of-custody form, placed in an ' on-site refrigerator and picked up by a California Department of Health Services (DHS) certified laboratory for analysis for 1 • Total petroleum hydrocarbons as diesel, oil and gasoline (TPHg, TPHd and TPHo) by ' EPA Method 8015 • Volatile aromatic compounds — benzene, toluene, ethyl benzene and total xylenes lie (BTEX) with Methyl tert-Butyl Ether (MTBE) by EPA Method 8020 Environeering,Inc Project No 01-008 011 Page 3 I