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Deep Wells . At the time of the fourth quarter 2005 monitoring event, groundwater was encountered in the deep monitoring wells at depths ranging from 49 70 to 50 66 feet bgs Groundwater elevations had Increased between 0 01 and 0 10 feet in all deep wells except for MW-17, which decreased 0 02 feet since the previous monitoring event (August 15, 2005) Groundwater monitoring data were normalized to MSL and used to prepare a groundwater elevation contour map (Figure 6) The groundwater flow was generally to the northeast at an average gradient of 0 0011 ft/ft Groundwater flow in the deep wells has historically been toward the south and east TPHG and benzene were reported in wells MW-8 through MW-10 Benzene was also reported in wells MW-11 and MWA7 The highest concentrations of TPHG (120,000 µg/L) and benzene (17,000 µg/L) were reported in well MW-9 1,2-DCA was reported in wells MWA0 (30 Pg/L) and MW-17 (2 2 µg/L) MTBE, TBA, DIPS, ETBE, TAME, or EDB were not reported in any of the deep wells These analytical results are generally consistent with historical data TPHG, benzene, and MTBE concentrations for samples collected and analyzed during the fourth quarter 2005 are included on Figure 7 Tentatively Identified Compounds SJCEHD has requested that all peaks detected in the analyses be reported A copy of the laboratory tentatively identified compounds (TIC) report is attached Tentatively identified compounds were reported in wells VEW-1, VEW-2, MW-8, MW-10, and MW-18 Results of the TIC analysis are summarized in Table 3 ATTACHMENTS • Table 1 Groundwater Elevation and Analytical Summary • Table 2 Groundwater Analytical Results for Oxygenates and Additional Compounds • Table 3 Summary of TIC Analysis Results • Figure 1 Site Location Map • Figure 2 Groundwater Elevation Contour Map, Shallow Groundwater Wells (Fourth Quarter 2005) • Figure 3 Groundwater Analytical Summary, Shallow Groundwater Wells (Fourth Quarter 2005) • Figure 4 Depth to Groundwater, Mid-Depth Groundwater Wells (Fourth Quarter 2005) • Figure 5 Groundwater Analytical Summary, Mid-Depth Groundwater Wells (Fourth Quarter 2005) • Figure 6 Groundwater Elevation Contour Map, Deep Groundwater Wells (Fourth Quarter 2005) • Figure 7 Groundwater Analytical Summary, Deep Groundwater Wells (Fourth Quarter 2005) • Appendix A Field Data Sheets • Appendix B Sampling and Analysis Procedures • Appendix C Certified Analytical Reports and Chain-of-Custody Documentation • K\Apache PlasticslQuanerly reports\20051Apache_4Q05 DOC STRATU5