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DISCUSSION At the time of the third quarter monitoring event, groundwater was encountered in the monitoring wells screened within the upper zone (wells screened between 46 5 and 70 feet bgs) at depths ranging from 48 48 to 50 71 feet bgs, with well MW-3 being dry Groundwater was encountered in the monitoring wells screened within the lower zone (wells screened between 94 and 115 feet bgs) at depths ranging from 49 96 to 53 95 feet bgs Groundwater elevations decreased approximately 3 20 to 3 35 feet in upper zone wells (except well MW-4, which only dropped 0 99 feet) since the May 20, 2002, monitoring event In the lower zone wells, groundwater elevations decreased 3 15 to 3 64 feet (except well MW-12, where groundwater rose 2 88 feet) The groundwater flow direction on August 27, 2002 was calculated to be towards the northeast at an average gradient of 0 0013 ft/ft in the upper zone Groundwater flow in the upper zone was initially towards the west and southwest, but since 1995, groundwater flow in the upper zone has consistently been toward the east and southeast In the lower zone, groundwater flow during the third quarter 2002 was toward the east at an average gradient of 0 04 ft/ft Groundwater flow in the lower zone has historically been toward the south and east TPHG and BTEX were detected in the samples collected from wells VEW-1, VEW-2, MW-4, MW-6, and MW-8 through MW-10 at concentrations generally consistent with historical data The highest concentrations of TPHG (160,000 pg/L) and benzene (21,000 pg/L) were detected in well MW-9 (screened in the lower zone) MTBE (1 0 pg/L) was detected in the sample collected from well MW-5 (screened in the upper zone) 1,2-DCA was detected in wells MW-2 (390 µg/L), MW-5 (5 6 pg/L), and MW-6 (2 0 pg/L), screened within the upper zone, and in wells MW-9 (780 pg/L), MW-10 (13 pg/L), MW-11 (3 2 pg/L), and MW-12 (1 7 pg/L), screened within the lower zone ATTACHMENTS • Table 1 Groundwater Elevation and Analytical Summary • Table 2 Groundwater Analytical Results for Oxygenates • Figure 1 Site Location Map • Figure 2 Groundwater Elevation Contour Map, Upper Water Bearing Zone (Third Quarter 2002) • Figure 3 Groundwater Elevation Contour Map, Lower Water Bearing Zone (Third Quarter 2002) • Figure 4 Groundwater Analytical Summary(Third Quarter 2002) • Appendix A Field Data Sheets • Appendix B Sampling and Analysis Procedures • Appendix C Certified Analytical Reports and Chain-of-Custody Documentation