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.. 1 These results indicate that water levels have risen since October 1992 . Among the three previously monitored wells, the average rise is 5. 43 feet, with the greatest rise in MW-5 (5 . 53 ft) . There has been a slight change in relative elevations between the wells, and the level in MW-4 is now slightly higher than that in MW-1- The groundwater gradient was calculated to be 0. 0037 ft/ft in a S 300 W direction. Relative groundwater elevations in each of the wells are contoured in Figure 3 . 5.0 CONCLU8ION8 AND RECOMMENDATIONS 5.1 Lateral Extent of Boil Contamination Eight soil borings have been drilled since assessment of this site began. A total of 19 soil samples from these borings have been analyzed for hydrocarbon contaminants. Three samples, all from MW- 1, were contaminated with gasoline and BTE&X. No samples from any of the other borings were contaminated. These results indicate that soil contamination is limited to the soil beneath the former UST, and does not extend far beyond MW-1. The estimated zero line of soil contamination is depicted in Figure 4. 5.2 Lateral Extent of Groundwater Contamination Figures 5 and 6 are contour maps of TPH and benzene concentrations in groundwater, based on data obtained in the present phase of investigation. The zero line of conta-mi "Lies between r-M-3 and MW-7 on the east and between MW-4 and MW-6 on the north. The presence of contamination in MW-4 (i.e. north of the former UST) is probably due to the east-northeast groundwater gradient that existed as a result of pumping of the Lodi Municipal well east of the site (the well is no longer in use) . The absence of contamination in MW-7 indicates that this contamination did not m migrate as far east as that well. The most recent data from MW-5 indicates that TPH as gas does not extend as far as MW-5 in the down gradient direction. Toluene is still present in groundwater from MW-6, but benzene and TPH were not detected during this monitoring event. t5.3 Groundwater Flow Direction Groundwater has risen more than 5 feet since October 1992 . The rise has apparently not been uniform in all wells, resulting in a shift in groundwater gradient. The gradient shift could be the result of the discontinuance of pumping from the municipal well. The present ilvW d1reUL.1Uj1 is 3 jV�" is owaaLu 5. 4 Futuro Work For sites with both soil and groundwater contamination, Appendix A 4 �1