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�hf 27 February 2004 AGE-NC Project No 99-0624 ' Page 3 of 4 ' Inferred to be flowing towards the south-southwest The average ground water gradient was determined to be approximately 0 002 ft/ft Figure 3 Illustrates the contoured ground water elevations as measured on 23 February 2004 1 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' TPH-g was detected in the water samples collected from wells MW-2 and MW-3 at concentrations of 33,000 p g/l and 440 gg/l,respectively Benzene,ethylbenzene and xylenes were only detected in ' the samples collected from well MW-2 at concentrations of 9 6 µg/1, 5 9 µg/1 and 22 µg/1, respectively i ' The fuel additive MTBE was detected in samples from wells MW-1, MW-2 and MW-3 at concentrations ranging between 58 ug/l(MW-1)and 33,000 gg/l(MW-2) TAME,TBA and ETBE were detected in sample MW-2 at concentrations of 110 µ.g/1, 19 �Ig/l and 4 1 µg/1, respectively 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 The laboratory report(CTEL Project No CT214-0402065)and chain- ' of-custody forms are presented in Appendix C ' 4.0. SUMMARY AND CONCLUSIONS ' The following conclusions were drawn from the results of this investigation • The depth to ground water at the site was approximately 52-53 feet below surface grade, or approximately 14 10 to 14 30 feet below mean sea level ' 0 Ground water flow direction in the area of wells MW-1 through MW-4 and MW-6 was inferred to be towards the south-southwest at an approximate gradient of 0 002 f1/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 ' a TPH-g was detected in the ground water samples collected from wells MW-2 and MW-3 at concentrations of 33,000 gg/l and 440 µg/l, respectively, between November 1999 and ' February 2004 TPH-g concentrations have fluctuated from 140µg/1 to as high as 33,000µg/l in samples from well MW-2 • MTBE was detected from wells MW-1, MW-2, and MW-3 at concentrations as high as ' 33,000 µg/l (MW-2) The latest data indicates a steady increase of dissolved MTBE, likely from the vertical migration through soil or lateral migration of dissolved MTBE from a ' Advanced GeoEnvironmental,Inc