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' 12 December 2005 AGE-NC Project,No 97-0333 Page 8ofII PCE was detected in forty-four out of forty-seven ground water samples analyzed at concentrations as high as 1,400'Wi(MW-1 OB),TCE was detected in ground water samples MW-2,MW-3,MW-7 ' (A-F), MW-8(B-D, F), MW-9B, MW-10(A-F), MWA I(C-D), MW-12 (B-D) and MW-13C at concentrations as high as 410 µg/l (MW-10B) An iso-concentration map displaying the estimated extent of dissolved PCE in First Zone water is depicted on Figure 10 ' No other constituents of concern were detected above laboratory reporting limits in the ground water samples collected during the second quarter 2005 sampling event Analytical results of ground water monitoring well samples are summarized in Tables 5 and 6 GeoTracker confirmation pages of the submitted laboratory electronic deliverable format (EDF) files are included in Appendix B, the laboratory reports(CTEL Laboratory I D Nos 0507-020 and 0507-026),quality assurance/quality control (QA/QC) reports, and chain of custody forms are presented in Appendix F r 4.0. SUMMARY AND CONCLUSIONS Previous soil characteristics data obtained b a CPT investigation enabled AGE to define four high Y g g permeability, informal hydrogeologic units (CPT Site Investigation - Fourth Quarter 2000, dated 07 February 2001) The informal hydrogeologic units were defined as First Zone (15-47 feet bsg), Second Zone (58-92 feet bsg), Third Zone (102-120 feet bsg), and Primary Aquifer Zone ' (128-150 feet bsg), and are separated by less-permeable, fine-grained intervals The results of pump and treat ground water remediation between 15 March 2005 and 08 June 2005 ` are as follows • Approximately 331,560 gallons of hydrocarbon-impacted groundwater were extracted from well EW-1,which was completed in the First Zone aquifer A total volume of approximately ! 3,468,283 gallons of hydrocarbon-impacted ground water has been treated at the site since start-up in January 2002 (Table 1) • Dissolved MTBE was detected from grab samples collected at the influent end of the treatment system at concentrations between 1,100 µg11 and 3,500 lig/l, laboratory analysis of grab water samples collected at the effluent end did not detect any constituents of concern during the second quarter 2005 (Table 2) • Between 15 March 2005 and 08 June 2005, an estimated 4 7 pounds of MTBE were extracted from ground water(Table 1, Appendix C), a total mass of 265 pounds of MTBE have been removed since initiation of the pump and treat system on 21 January 2002 A plot of cumulative ground water pump and treat mass removal versus time and a plot of influent ground water MTBE concentrations versus time are included in Appendix D, MTBE concentrations in the influent samples increased this quarter, but still indicate an overall Advanced GeoEnvironmentai,Inc