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had stabilized (Table 1) . These parameters were measured at two- gallon intervals using a Hydac water analyzer. The water was stored on-site in a DOT approved drum. 3 .2 Water Sampling Water samples were collected using a disposable plastic bailer. Three 40-m1 EPA vials and two 1-liter amber bottle of water were collected from each well and transmitted in a chilled container to WEST Laboratories in Davis. Each sample was analyzed for total petroleum hydrocarbons (TPH as gasoline, diesel, and motor oil) and purgeable aromatics (BTEX) in accordance with the appropriate EPA methods. The laboratory report and chain of custody are included in Appendix A. 4 . 0 FINDINGS 4. 1 Groundwater Gradient The relative water elevation for the monitoring wells was calculated by subtracting the water depth from the casing elevation (Table 2) . The data .indicate that water levels have declined more than 6 inches in all wells since March 1993 . This may be due to tidal effects, although similar results have been obtained at numerous other sites in San Joaquin County, indicating that this is probably a regional trend due to seasonal variations in rainfall. As in the previous sampling events, the water level is highest in MW-3 and lowest in MW-1, confirming that flow is generally to the south, away from the ship channel . In March, the hydraulic gradient was 0. 0093 ft/ft to S380E. Present data yield a similar direction, (S470E) , but a much flatter gradient (0. 0051 ft/ft) (Figure 2) . Table 2 Groundwater Data* Depth to Relative Relative Groundwater Groundwater Well No. Casing Elevation Elevation 3/93 9/93 3/93 9/93 MW-1 100. 31 9 . 17 9. 61 91. 14 90 . 70 MW-2 99 . 77 8 . 24 8.95 91. 53 90. 82 MW-3 1 100 . 13 8 . 04 8 . 67 92 . 09 91. 46 * All measurements in feet 6