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Cumulative groundwater analytical results are summarized in Table 11. The analytical laboratory data sheets can be found in Appendix B. 4.2 Groundwater Sample Laboratory Analytical Results Laboratory analyses indicated that aromatic volatile hydrocarbons (BTEX) and total petroleum hydrocarbons as gasoline (TPH-g) were detected in wells MW-2 and MW-5 above method detection limits. Groundwater samples collected from MW-1, MW-3 and MW-4 did not contain TPHg or BTEX components above method detection limits. The petroleum oxygenate MTBE was not detected in any of the groundwater samples collected from all five wells. w Monitor well MW-2 contained 1200 ug/l of TPH-g and 45 ug/1 of benzene. MW-5 had levels of TPH-g at 2500 ug/I and benzene at 60 ug/l. a.. See Table 11 for Cumulative Groundwater Analytical Results. The analytical laboratory data sheets can be found in Appendix B. 4 5.0 CONCLUSIONS 5.1 Soil Contamination Monitor well MW-5 was drilled and installed on September 3, 1999. The soil samples collected during the drilling operation contained increasing levels of TPH-g and BTEX with depth, peaking with the samples collected at the 15 foot sampling interval. The 15 foot interval ` sample had TPH-g results of 1300 mg/kg, benzene at 4.1 mg/kg, toluene at 1.2 mg/kg, ethylbenzene at 8.4 mg/kg, and total xylenes at 31 mg/kg. The next and last sample at the 20 foot interval showed the petroleum contamination nearly gone with TPH-g results of not detected (<1.0 mg/kg), benzene just above the detection limit at 0.010 mg/kg, toluene at 0.047 mglkg, ethylbenzene at 0.042 mg/kg, and total xylenes at 0.30 mg/kg. The analytical laboratory data sheets can be found in Appendix B. 5.2 Groundwater Contamination Groundwater contamination was detected in monitoring well MW-2 and the newly installed MW-5. The groundwater contamination consisted of total petroleum hydrocarbons as gasoline, and associated aromatic volatile fuel components (BTEX). No MTBE was detected in wells MW-2 and MW-5, and no contamination was detected in the other three wells. The groundwater contaminant plume in the vicinity of well MW-2 and adjacent MW-5 is inferred to extend down-gradient of well MW-2 approximately 60 feet. The plume is inferred to extend up-gradient and cross-gradient approximately 15 and 20 feet, respectively. Figure 4 illustrates the inferred limits of groundwater contamination for the September 1999 sampling event. 5.3 Groundwater Flow Direction and Gradient JJW prepared a groundwater potentiometric surface map based on the static groundwater ,r elevations measured on September 13, 1999. The shallow groundwater was calculated to flow toward the north-northeast (N 7 E) at a gradient of approximately 0.0048 tuft. Figure 3 illustrates the ground-water potentiometric contour surface and flow direction. �. 4 JJW GEOSCIENCES Inc.