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Il 31 January 2005 AGE-NC Project No 96-0232 Page 5 of 9 laboratory report noted that the TPH-d sample chromatogram had significant diesel range compounds MTBE was detected in eighteen water samples collected from monitoring wells MW-2, MW-4, MW-6B, MW-7, MW-8A, MW-9A, MW-11 (A and B), MW12B, MW-13B and MW-14 through MW-18, MW-19A and MW-20 (A and B) at concentrations as high as 900 �Lg/l (MW-19A), Isoconcentration maps displaying the estimated extent of dissolved MTBE in First Zone and Second Zone aquifer are depleted in Figures 8, 9 and 10 No other constituents of concern were detected above laboratory reporting limits in the water samples collected during the fourth quarter 2004 sampling event Analytical results of ground water monitoring well samples are summarized in Tables 3 and 4 The laboratory reports (McCampbell Analytical Inc Work Order Nos 0412516,0412540 and Cal Tech Environmental Laboratories I D No 0412-247) and chain of custody forms are presented in Appendix C, GeoTracker confirmation pages of the submitted laboratory electronic deliverable format (EDF) files are Included in Appendix D 3.0. SUMMARY OF FINDINGS FROM QUARTERLY ACTIVITIES Previous soil characteristics data obtained by a CPT investigation enabled AGE to define five Informal hydrogeologic units (Final Remediation Plan, dated 31 August 2000) The Informal hydrogeologic units were defined as First Zone (10-35 feet bsg), Second Zone (40-60 feet bsg), Rocky's Upper Zone (65-75 feet bsg), Secondary Aquifer Zone (85-105 feet bsg), and Primary Aquifer Zone (130-150 feet bsg) The Rocky's Upper Zone was the shallowest ground water zone screened in the destroyed Rocky's domestic drinking water well Between November 2000 and 17 August 2004, a total volume of 27,086,201 gallons of MTBE- impacted water was treated at the site utilizing pump-treat and carbon filtration remediation technology, due to the lack of cost effectiveness for the clean-up of MTBE-impacted ground water, pump-and-treat operations were suspended on 17 August 2004 The results from the ground water monitoring and sampling events performed in December 2004 are as follows • Generally,depth to ground water at the site varied between 12 and 15 feet bsg,ground water elevations ranged between 0 92 feet (MW-13B) and 2 20 feet (MW-lOE) below mean sea level (Table 2) • Net ground water flow direction in all informal hydrogeologic units was inferred to be east- southeast at both the Flag City Chevron and the Three B's Truck Plaza sites, hydraulic Advanced Ge0EnvironInental,Inc