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' 16 February 2004 • AGE-NC Project No 99-0624 ' Page 3 of 4 ' 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the water sample collected from wells MW-2 and MW-3 at concentrations I of 26,000 µg/1 and 110 µg11, respectively Benzene was not detected above laboratory reporting limits In the ground water samples collected this quarter Ethylbenzene and xylenes were detected only In the sample collected from MW-2 at concentrations of 27,µg/1 and 70 µg/l, respectively Utilizing EPA Method 8260,the fuel additive MTBE was detected In samples MW-1 MW-2 MW-3 p > and MW-4 at concentrations ranging between 40µg/1(MW-1)and 24,000µg/l(MW-2),and TAME ' was detected In sample MW-2 at a concentration of 130µg/1 No other constituents of concern were detected above laboratory reporting limits In the analyzed samples Previous and current analytical results of ground water monitoring well samples are summarized in Tables 3 and 4 The laboratory ' report (CTEL Project No CT214-0311091) and chain-of-custody forms are presented In Appendix B ' 4.0. SUMMARY AND CONCLUSIONS US ONS ' The following conclusions were drawn from the results of this investigation • The depth to ground water at the site was approximately 53-54 feet below surface grade, or ' approximately 15 00 feet below mean sea level • Ground water flow direction In the area of wells MW-1 through MW-4 and MW-6 was I inferred to be towards the south-southwest at an approximate gradient of 0 002 ft/ft Due to the low hydraulic gradient at the site, slight variations In ground water measurements or changes of recharge/discharge of the local ground water could greatly modify the inferred ' ground water flow direction • TPH-g was not detected In well MW-1, MW-6 and MW-7 during the fourth quarter 2003 In addition, benzene was not detected this quarter in samples collected from well MW-2 This is the first time benzene has not been detected in any of the wells since sampling began • TPH-g was detected In the ground water samples collected from wells MW-2 and MW-3 at concentrations of 26,000 µg/l and 110 µg/1, respectively, between November 1999 and November 2003, TPH-g concentrations have fluctuated from 140 µg/1 to as high as 26,000 gg/l in samples from well MW-2 • Utilizing EPA Method 8260B, MTBE was detected from wells MW-1, MW-2, MW-3 and MW-4 at concentrations as high as 24,000,µg/l (MW-2) The MTBE concentrations were above the Primary MCL of 13 µg/l In drinking water IAdvanced GeoEnvironmental,Inc I