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Cumulative groundwater analytical results are summarized in Table H. 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. Monitor well MW-2 contained 1200 ug/I of TPH-g and 45 ug/I of benzene. MW-5 had levels of ' TPH-g at 2500 ug/I and benzene at 60 ug/l. See Table II for Cumulative Groundwater Analytical Results. The analytical laboratory data sheets can be found in Appendix B. 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 mglkg, 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 mg/kg, 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 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. t4 JJW GEOSCIENCES Inc.