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20 July 2005 AGE-NC Project No. 95-0109 Page 3 of 5 3.1. GROUND WATER GRADIENT AND DIRECTION On 01 June 2005, the depth to ground water ranged from 56.06 feet to 58.96 feet below the tops of the well casings. Ground water elevations at the site ranged from 2.37 feet below mean sea level (MSL) in well MW-5 to 5.83 feet below MSL in well MW-22. Ground water levels were within the screened intervals of water table wells MW-1 through MW-14 and MW-16, wells MW-20 through MW-22, but ranged from approximately 17 to 54 feet above the screened intervals of the deep- screened wells MW-15 and MW-17 through MW-19. Data from wells MW-1 through MW-5 were not used to infer ground water flow direction or gradient because these wells are screened at different intervals than the remaining wells. The ground water for the well network was inferred to be flowing towards the south on-site and off- site at an average gradient of approximately 0.001 ft/ft. Figure 3 illustrates the contoured ground water elevations; historical ground water flow directions are summarized in Table 6. 3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES • TPH-g was detected in ground water samples from wells MW-8, MW-9 and MW-14 at concentrations of4,000 micrograms per liter(µg/1),6,100µg11,and 1,400µg/1,respectively.Benzene was detected in the samples collected from wells MW-9 and MW-14 at concentrations of 2.9 µg11, and 32 pg/l, respectively. Toluene was detected in the sample from well MW-14 at a concentration of 26 µg11. Ethylbenzene and xylene were detected in the samples collected from wells MW-8, MW-9 and MW-14 at concentrations as high as 20 µg11 (MW-8) and 270 µg/1 (MW-14), respectively. The fuel additive 1,2-DCA was detected in samples collected from wells MW-9 (off-site) and MW-14 at concentrations of 19 µg11 (MW-9) and 9.3 µg/1 (MW-14) . No additional analytes were detected above laboratory limits in the ground water samples collected. The analytical results from the June 2005 monitoring event are presented in Tables 2, 3 and 4. Analytical results to date are summarized in Table 5. The approximate extent of dissolved TPH-g, benzene and 1,2-DCA are depicted on Figures 4, 5 and 6. The laboratory report (CTEL Project Number CT214-0506038) and chain of custody forms are included in Appendix B. Confirmation pages of the submitted laboratory electronic digital format (EDF) files and depth to water measurements are included in Appendix C. Advanced CeoEnvironmental,Inc.