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I15 December 2003 AGE-NC Project No 95-0173 IPage 7 of 9 ' During the June 2003 through September 2003 operational period, the mass of hydrocarbons extracted by the SVE system was calculated to be approximately 567 pounds, or equivalent to a volume of 91 gallons of gasoline Added to the estimated 1,607 gallons of hydrocarbons extracted ' from the SVE system since 11 April 2000 (start-up), the total volume of hydrocarbons extracted to date is estimated at 1,698 gallons (Table 7) A plot of the cumulative volume (gallons) of hydrocarbons extracted to date Is included with Appendix E The volume/mass calculations for ' extracted hydrocarbons are included with Appendix F ' S.O. CONCLUSIONS The implications from the September 2003 ground water monitoring event are as follows ' Ground water flow direction at the site was generally oriented northeast across the site at a gradient of 0 007 ft/ft or less Due to the generally low gradient at the site, slight variations ' In ground water measurements or changes of recharge/discharge of the local ground water could greatly modify ground water flow direction • The decrease of ground water elevation of approximately 3 20 feet between June 2003 and ' 0 the September 2003 monitoring events is probably due to seasonal fluctuation G Ground water at the site was significantly above the screen Intervals (drowned) of wells ' AW-1 (A and B), AW-2 A and B) and MW-13 (A, B and C) and probably yield samples more representative of deeper ground water conditions The groundwater elevation appeared to be within or near the screen intervals of all other wells at the site and should be ' representative of shallowest ground water conditions • Ground water elevation data collected on 23 September 2003 does not suggest that ground ' water mounding may have occurred due to the on-going IAS activities _ • The elevated concentrations of petroleum hydrocarbons detected In samples collected from wells AW-1B (screened 50 to 60 feet bsg), AW-2A (screened 40 to 45 feet bsg), AW-2B ' (screened 60 to 70 feet bsg)and MW-4(screened 30 to 50 feet bsg) indicate that these wells are within the remaining dissolved petroleum hydrocarbon "core area" of the plume (Figures 4) • The significant decrease In hydrocarbon concentrations observed at wells AW-]A(screened 39 to 44 feet bsg) and AW-lB may be attributed to the August and September 2003 IAS ' activities performed at AW-1B, the rapid, upward movement of hydrocarbons was substantiated with the observed `spike' in the September 2003 influent air flow sample • Generally, an apparent trend of decreasing dissolved petroleum concentrations is evident in samples collected from wells MW-1,MW-2,MW-3, MW-6, AW-1 (A and B), the trend of ' Advanced GeoEnvtronmental,Inc