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15 January 2005 AGE-NC Project No 96-0235 Page 4of5 Analytical results of water samples collected during the fourth quarter of 2004 are summarized in ' Tables 2 and 3,analytical results from previous monitoring events are summarized in Tables 4 and 5 Figures 5 and 6 illustrate the ground water contamination plumes in upper and lower ground water Intervals,respectively The laboratory report(CTEL Project No CT214-0411150),chain of custody forms and the laboratory quality,assurance/quality control (QA/QC) reports are included In Appendix C GeoTracker confirmation pages of the submitted laboratory electronic deliverable ' format (EDF) files are Included in Appendix D _ E 4.0. SUMMARY AND CONCLUSIONS Based on the data collected from the former northern UST cluster area, AGE finds ' The shallow-screened data Infer a net flow towards the east ataadient of gr 0 001 ft/ft, the deep-screened data delineated a ground water flow direction toward the south at a gradient r ' of 0 005 ft/ft Ground water gradient and flow direction observed during the fourth quarter 2004 was similar to the previous quarter ' TPH-g was detected in the samples collected from MW-9 and MW-14B at a concentration of 200 µg/1 ' MTBE was not detected in the shallow-screened wells sampled during the fourth quarter 2004 MTBE was detected by EPA Method 8260B In the deep-screened wells MW-9, MW-10,MW-11B,MW-12B,MW-13B and MW-14B at concentrations as high as 210µg/1 ' (MW-9) 1,2-DCA was detected in groundwater samples collected from wells, MW-11B, MW-1313 and MW-14B • The most Impacted ground water appears to be centered around the former UST dispenser ' location Although BTEX was not detected in current water sample collected at this area,the previous detections at well EW-1 does demonstrate a significant Impact to ground water at the southern edge of the former dispenser Island The vertical extent of the contamination plume, as`well as,the lateral extent at the former UST cluster, was generally defined by previous CPT soil boring samples - Based on the data collected from the former southern UST No 3 area, AGE finds r • The ground water flow direction at the shallow-screened level was inferred to be towards the r east at a gradient of 0 003 ft/fl, ground water flow direction at the deep-screened level was inferred to-be toward the south-southwest at a gradient of 0 014 ft/ft Ground water gradient and flow direction observed during the fourth quarter 2004 were similar to the previous quarter Advanced CeoEnvironmental,Inc