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i deposits which occur throughout the Stockton area. Regional gradients in the area are variable due to various pumping influences. No surface water bodies occur within one half mile of the site. i 4 .2 Groundwater Gradient The wellhead elevations of monitoring wells MW-1 through MW-8 were i surveyed to establish relative vertical control. This data was i combined with the depths to groundwater measured in monitoring i wells MW-1 through MW-8 on September 26, 1994 to evaluate the elevation of the groundwater surface in each well and the groundwater gradient across the site. A map of the potentiometric surface at the site is presented in Figure 2 . Data used to prepare this Figure are presented in Table 2 along with water level data obtained from earlier work. Based on this data, the evaluated kgroundwater flow direction on September 26, 1994 beneath the site was to the northeast; the calculated hydraulic gradient was 0. 01 ft/ft. E 5.0 LABORATORY ANALYSIS OF SOIL AND WATER SAMPLES Sixteen soil samples collected from borings MW-7 and MW-8 were selected for laboratory analysis. The samples were analyzed for Total Petroleum Hydrocarbons (TPH) as gasoline using Environmental Protection Agency (EPA) Method 8015; Total Petroleum Hydrocarbons (TPH) as diesel using EPA Method 8015; and for benzene, toluene, ethylbenzene, and total xylenes (BTEX) using EPA Method 8024. Groundwater samples collected from monitoring wells MW-6 through ' MW-8 were analyzed for TPH as gas, TPH as diesel, BTEX, and purgeable organic priority pollutants (VOCs) using EPA Method 624. 6.0 LABORATORY ANALYTICAL RESULTS 6. 1 Soil Results of previous and recent soil sample analyses are summarized in Table 3 . Petroleum hydrocarbons were not detected in any of the soil samples collected from borings MW-7 and MW-8. Laboratory analytical reports and chain of custody records for the soil samples are included in Appendix C. 6.2 Groundwater The results of the previous and most recent groundwater sample analyses are summarized in Tables 4A and 4B. Aromatic hydrocarbons were detected in all three wells. Additionally, the chlorinated F hydrocarbons 1, 2 DCA and PCE were detected in wells MW-6 and MW-7. i Although no chlorinated compounds were reported for MW-8, the method detection limits were extremely high due to sample dilution. Laboratory analytical reports and chain of custody records for the i water samples are included in Appendix D. 6