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top of casing (btc), as measured on 11 September 2002 in the four groundwater monitoring wells ' (MW-1, MW-2, MW-3 and MW-4 respectively) installed on site The elevation of groundwater in MW-1, MW-2, MW-3 and MW-4 was calculated by EI to be at 19 78, 19 08, 19 86 and 19 95 tfeet below mean sea level respectively, based upon casing elevation data from Kier & Wright Civil Engineers and Surveyors 1 3.0 FINDINGS ' 3.9 Groundwater Level Measurements ' The elevation of groundwater in MW-1, MW-2, MW-3 and MW-4 was calculated by EI to be at 19 78, 19 08, 19 86 and 19 95 feet below mean sea level respectively on 11 September 2002 ' EI utilized the groundwater measurements to determine the direction of groundwater flow and ' the groundwater gradient present beneath the surface The groundwater direction of flow for the area was inferred southeasterly at a gradient of 0 01 ft/ft to 0 004 ft/ft The groundwater elevation at the site decreased an average two (2) feet between June 2002 and September 2002 The gradient increased slightly during that period Groundwater elevations are listed in Table 1, and shown graphically in Figure 4 3.2 Groundwater Sample Analysis Results The groundwater was sampled on 11 September 2002 MW-1 continued to show gasoline, diesel and PAX contamination at a levels similar to that found in the previous quarter Aliv MW-2 shows significant motor oil contamination as well as moderate contamination from diesel Minor contamination from BTEX remains, but no gasoline, MTBE or oxygenates contamination is present EMW-3 is free from contamination once again MW-4 continued to showed gasoline, BTEX and DIPE contamination All groundwater samples secured b EI were logged in a chain-of-custody form lac - Y gg y , p edinanon site refrigerator and picked up by a California Department of Health Services (DHS) certified Environeenng,Inc Project No 02 009 17 Page 3