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' 24 June 2005 {� AGE-NC Project No 95-0103 ' Page 10 of 12 • The average ground water level was approximately 11 7 feet below the top of the casing An increase of the ground water elevation of greater than 3 feet has occurred since the monitoring event in December 2004 The ground water flow direction was generally southeast from the location of well MW-6 and well MW-3,and south inward toward the area of the extraction wells EW-2 and EW-3 • The ground water table was above the screened interval of wells MW-1 through MW-4 and within the screened interval of wells MW-5 and the extraction wells Water samples collected from deeper screened wells(MW-1)may not be representative of shallow ground water conditions However the remaining wells should yield samples representative of shallow ground water conditions • Between December 2004 and May 2005,the ground water extraction and treatment system processed approximately 219,928 gallons of water The total volume of ground water treated as of April 2002 is approximately 3,701,758 gallons The average daily discharge rate was approximately only 1,500 gallons per day,were continuous pump operation of between 5-10 gpm would yield more ground water • TPH-g,BTEX compounds and MTBE were detected in influent samples and ground water extraction samples collected from wells EW-1,EW-2 and EW-3 Extraction well VW-6 was .' not operation during this remediation period The dissolved TPH-g concentration trends increase in extraction well EW-3 and decreased in extraction wells EW-1 and EW-2 over the second quarter 2005 Additionally, the benzene concentrations in ground water extraction samples also showed a stabilization or slight increase over the first and second quarters of 2005(Appendix D) MTBE was not detected in the ground water extraction wells during the 1 first and second quarter 2005 • Based on the amount of ground water processed and laboratory analytical results, approximately 0 298 lbs of benzene and 14 68 lbs of TPH-g were removed from the extracted ground water (Appendix D) Cumulative totals of 6 758 lbs of benzene and 193 4 lbs of TPH-g are estimated to have been extracted since ground water treatment began 1 on 02 April 2002 • TPH-g and BTEX concentrations increase over the first quarter 2005 in well at the core area I of the dissolved plume (VE-1 and MW-4) as depicted in Figures 4 and 5 This increase in TPH-g and BTEX concentrations may be attributed to capture and drawing-in of the northeastern edge of the dissolved plume and the rise in the ground water level greater than 1 three feet over the first quarter This increase of the water level,contacting ground water with adsorbed soil mass under the building at the site may have increase the dissolved mass greater than was removed from the aquifer through active ground water recovery ' • MTBE was detected in well VE-1 at 34 µg11 and other fuel additives (TAME) were also • detected for the first time in well VE-1 1 Advanced GeoEnvironmental,Inc c 1