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1 ' 30 March 2005 • AGE-NC Protect No 95-0130 ' Page 10 of 13 I Laboratory I D Nos 0411-134 and 0412-235)are summarized in Table 8,GeoTracker confirmation pages of the submitted laboratory electronic deliverable format(EDF)files are included in Appendix D, laboratory reports are included in Appendix I tUtilizing a Blue-White Industries F-2000 flow meter,total flow(totalizer)was recorded between 17 November 2004 and 29 December 2004 (Table 9) During this time, the extraction and treatment interim ground water remediation system was in operation for approximately 42 days Based on the total of approximately 35,360 gallons of water recorded during this time, AGE estimated that an average 842 gallons of water was discharged per day during this time 4 6 MASS-VOLUME REMOVAL CALCULATIONS IBetween 17 November and 29 December 2004, an estimated 14 04 pounds of total petroleum hydrocarbons were extracted from ground water(Table 9) The November 2004 to December 2004 mass-volume calculations of gasoline-impacted ground water extracted from the ground water extraction and treatment system are presented in Appendix J 5.0. SUMMARY AND CONCLUSIONS tThe implications from the December 2004 ground water monitoring event are as follows I • Ground water flow direction within Hydrologic Units 1, 2 and 3 was inferred to be towards the northeast at gradients between 0 002 ft/ft and 0 006 ft/ft (Figures 3 and 4) • Between January 1995 and August 2001, ground water elevations at the site generally increased from 44 feet to 23 feet below MSL, since August 2001 and present day, ground water elevations have generally fluctuated between 24 feet and 29 feet below MSL(Table 2) • Ground water at the site was generally observed between 44 and 46 feet bsg and was above the screened intervals of wells MW-1 through MW-5,MW-6(B-E), MW-7 (B-E),VW-1 C, VW-2A and VW-3A (i a screened below ground water table), and may not yield samples Ifully representative of shallowest ground water conditions • The greatest concentrations of Top Filling Station dissolved TPH-g and BTEX were detected in samples collected from wells MW-7B (50-55 ft), VW-1C (48-63 ft) and VW-2A (43-63 ft) which is consistent with previous monitoring results (Table 4) TPH-g concentrations were detected as high as 230,000 µg/1 from well VW-2A and benzene as high as 35,000µg/l from well MW-713 Additionally,the deepest detection of dissolved TPH-g and BTEX were . detected in samples collected from well MW-6E (137-142 feet), the approximate extent of dissolved TPH-g is depicted in Figures 5 and 7 Advanced GeaEnnroamental,Inc C