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1 O1 December 2004 AGE-NC Project No 97-0333 ' Page 8of11 ' MTBE (utilizing EPA Method 8260M) was detected in twenty-one water samples collected from monitoring wells MW-1, MW-2, MW-3, MW-7 (A-F), MW-8 (A-C), MW-9 (A and B), MW-11 (B-D), MW-12 (A-C) and MW-13B at concentrations as high as 23,000 pg/l (MW-2), iso- concentration maps displaying the estimated extent of dissolved MTBE in First Zone and Second Zone aquifer are depicted on Figures 8 and 9 ' TAME was detected in seven water samples collected from monitoring wells MW-1,MW-2,MW-3, MW-7 (A, B and E) and MW-12B at concentrations as high as 240 µg/l (MW-2), 1,2-DCA was detected in nine water samples collected from monitonng wells MW-7(B, C and E),MW-8 (B-D), ' MW-10B and MW-11 (B and C) at concentrations as high as 10 ggll (MW-IOB) PCE was detected in 45 of 46 water samples collected from monitoring wells MW-1 through ' MW-13 at concentrations as high as 1,100 gg/l from wells MW-4 and MW-8B, TCE was detected in 34 water samples collected from wells MW-4,MW-5,MW-7(A-F),MW-8 (B-F),MW-9(A-C), MW-10 (A-F), MW-11 (B-E), MW-12 (A-D) and MW-13 (A-D) at concentrations as high as 220 gg/l from well MW-10B An iso-concentration map displaying the estimated extent of dissolved PCE in First Zone water is depicted in Figure 10 No other constituents of concern were detected above laboratory reporting limits in the water lie samples collected during the second quarter 2004 sampling event Analytical results of groundwater ' monitoring well samples are summarized in Tables 3 and 4 The laboratory reports(Castle Analytical Laboratory Reference Nos 7092 and 7093)and chain of custody forms are presented in Appendix G, GeoTracker confirmation pages of the submitted laboratory electronic deliverable format(EDF)files ' are included in Appendix B ' 4.0. SUMMARY AND CONCLUSIONS r Previous soil characteristics data obtained by a CPT investigation enabled AGE to define four high ' permeablility, informal hydrologic 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 10 March 2004 and 23 June 2004 ' are as follows • Approximately 304,196 gallons of hydrocarbon-impacted groundwater were extracted from ' well EW-1,which was completed in the First Zone aquifer A total volume of approximately 2,546,400 gallons of hydrocarbon-impacted groundwater-has-been treated at the site since w ' Advanced GeoEnvironmental,Inc