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I 28 November 2005 AGE-NC Project No 99-0657 Page 3 of 5 the site, the ground water gradient is approximately 0 008 ft/ft This flow direction remains consistent with the previous monitoring events Figure 3 shows the contoured ground water elevations as measured on 08 August 2005 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the 08 August 2005 water samples collected from wells MW-1, MW-2, MW-4, MW-5, and MW-6 at concentrations ranging from 120 micrograms per liter(µg/1, MW-6) to 2,700 gg/1(MW-1) Benzene was detected in the samples collected from wells MW-2,MW-4,and MW-5 at concentrations of 18 µg/l, 86 µg/l, and 4 3 µg/l, respectively Toluene was detected in two of the August samples and ethylbenzene was detected in one water sample this quarter 7 3 µg/1 and 27 µg/l toluene in wells MW-2 and MW-4, respectively and 8 0 µg/l ethylbenzene in well MW-4 Xylenes were detected in wells MW-1, MW-2, and MW-4 at a maximum concentration of 86 µg/1 (MW-4) MTBE was detected in water samples collected from wells MW-1 through MW-4 and MW-6 at • concentrations ranging from 11 µg/l (MW-3)to 180 µg/l (MW-4) 1,2-DCA was detected in water samples collected from wells MW-1, MW-4, and MW-6 at concentrations of 6 4 µg/1, 13 µg/l, and 14 µg/l, respectively No target analytes were detected in the samples collected from the vertical profile ground water wells Analytical results of the ground water samples collected in August 2005 are summarized in Table 2 The laboratory report (CTEL Project No CT214-0508049), quality assurance/quality control (QA/QC) reports, and chain of custody forms are included in Appendix C 4.0. SUMMARY AND CONCLUSIONS The following conclusions were drawn from the results of this investigation • At the time of the August 2005 sampling event, depths to ground water ranged from 37 35 feet to 40 59 feet below the tops of the well casings Groundwater elevation at the site averaged approximately 5 89 feet above MSL,indicating a decrease in average ground water ' elevation of approximately 0 34 feet since the last monitoring event in April 2005 • Ground water flow was inferred to be flowing toward the southwest under a hydraulic gradient of approximately 0 007 ft/ft on the northern portion of the site, in the southern portion of the site,the ground water gradient is approximately 0 008 ft/ft This flow direction . remains consistent with the previous monitoring events Advanced GeoiJnvironmental,Inc