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04 March 2005 AGE-NC Project No. 98-0520 Page 3 of 4 concentrations of 270 micrograms per liter (µg11) and 1,400 µg11, respectively. Figure 4 illustrates ' the approximate distribution of dissolved TPH-g. Ethyl-benzene and xylenes were detected in sample MW-5 at concentrations of 85 µg11 and ' 47.1 µg11, respectively. No additional target analytes were detected at or above laboratory reporting limits in the ground rwater samples collected.Analytical results of ground water samples are summarized in Table 2.The laboratory report(CTEL Project No. CT214-0412173), quality assurance/quality control (QA/QC) ' report, and chain of custody forms are included in Appendix C. Documents confirming the upload of laboratory electronic deliverable format (EDF) files and depth to water measurements to GeoTracker are included in Appendix D. 4.0. SUMMARY AND CONCLUSIONS Based upon data collected from the site, AGE concludes: • On 21 December 2004,the ground water elevation at the site averaged approximately 15 feet above MSL,which represents an elevation increase of approximately 4.8 feet since the last monitoring event, resulting in a ground water elevation more consistent with prior monitoring events. Ground water flow was inferred toward the northwest under a shallow gradient of 0.001 ft/ft. • The ground water flow direction has been consistently northwest since the initiation of ground water monitoring in December 1999; however, the ground water gradient is very shallow and seasonal changes can greatly influence the direction and pattern of ground water ' flow. • TPH-g concentrations decreased this quarter in well MW-2;while increasing in well MW-5 located at the former UST area compared to last quarters data. TPH-g was not detected in ' down-gradient well MW-3 for the first time since monitoring began;and cross-gradient-well MW-1 did not have a TPH-g detection for the second consecutive monitoring event. • Ethyl-benzene and xylenes were detected only in well MW-5,though slightly higher then last quarter. Since December 2003, BTEX compounds have been detected only in well MW-S. • The vertical extent of impacted ground water has been defined;TPH-g has not been detected in deep-screened well MW-6 since the well was installed in December 2001. Impacted ground water apparently does not extend beyond 45 feet bsg. ' Advanced GeoEnvironmental,Inc.