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22 July 2002 <br /> AGE-NC Project No 98-0511 <br />' Page 3 of 4 <br /> in MW-1 at concentrations of 190 µg11, 180 µg/1, 330 gg/l and 1,800 gg/l, respectively, BTEX <br />' compounds were detected in MW-5 at concentrations of 82 gg/l, 4 5 pg/l, 28 µg/1 and 23 µg/1, <br /> respectively <br /> Utilizing EPA Method 8260B, MTBE was detected in the ground water samples collected from <br /> MW-1,MW-3 and MW-5 at concentrations of 42 gg/l, 19 gg/l and 120 gg/l, respectively No other <br /> fuel oxygenated compounds were detected above laboratory reporting limits <br />' Analytical results of ground water samples are summarized on Tables 2 and 3 The inferred lateral <br /> distribution of TPH-g,benzene and MTBE is illustrated on Figure 4 Copies of the laboratory report <br />' (Cal Tech Laboratory IDs 0206-045-1 through 0206-045-8)and chain-of-custody forms are provided <br /> in Appendix B <br /> I <br /> 4.0 SUMMARY AND CONCLUSIONS <br />' Based upon data collected from the site, AGE concludes the following <br /> • On 11 June 2002 the ground water elevation in the monitored area averaged 4 46 feet above <br /> mean sea level, ground water has decreased approximately 0 5 feet since the previous <br /> quarter The ground water flow direction was inferred to be generally westward under a <br />' gradient ranging from 0 002 ft/ft to 0 007 f1Jft <br /> • TPH-g was detected in ground water samples MW-1 and MW-5 at concentrations as high <br /> as 11,000 gg/l (MW-1) BTEX compounds were detected in samples MW-1 and MW-5 at <br /> concentrations as high as 190 µg/1, 180 gg/l, 330 gg/1 and 1,800 gg/l,respectively(MW-1) <br /> BTEX constituents were not detected in samples collected from the other six monitoring <br /> wells <br /> • MTBE was detected in samples MW-1,MW-3 and MW-5 at concentrations between 19 gg/l <br /> and 120 gg/l (MW-5), these concentrations are above the DHS Maximum Contaminant <br /> ILevel (13 gg/l) for MTBE in drinking water <br /> • Hydrocarbon-impacted ground water is not defined vertically and laterally along the east side <br /> Iof the site <br /> 5.0. RECOMMENDATIONS <br /> Based upon data collected from the site, AGE recommends <br /> • Continued quarterly ground water monitoring <br /> Advanced GeoEnvironmental,Inc <br /> I <br />