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I 06 January 2006 AGE-NC Project No 99-0559 Page 6 of 7 forms are included In Appendix C GeoTracker confirmation pages of the submitted laboratory electronic deliverable format (EDF) files are Included in Appendix D 4.0. SUMMARY AND CONCLUSIONS Based on data collected during the monitoring event, AGE concludes • Ground water elevation decreased an average of 2 78 feet as measured In HUI and HU2 between the June and November 2005 monitoring events The ground water flow direction varied with depth at the time of the November monitoring event, flowing toward a pezlometrlc depression located In the vicinity of the former UST area in HUI and HU2, south-southwest In HU3 and HU4,west-southwest in HU5U, south-southeast In HU5L and east In HU6 • The highest petroleum hydrocarbon concentrations were detected In shallow monitoring wells (screened In HUI and HU2) at the east edge of the UST area In general, TPH-g concentrations increased significantly in wells MW-2, MW-4, MW-5A, MW-6A and MW-7D, Increased slightly In wells MW-7A, MW-613, MW-713, MW-6C, MW-6C, MW-6D, MW-6E and MW-7E, and decreased or remained the same (non-detect) In the remaining wells TPH-g concentrations Increased slightly with depth In well MW-6 and MW-7 Total BTEX concentrations Increased In wells MW-2, MW-3, MW-7B, , MW-7C, MW-7D and MW-7E,decreased in wells MW-4,MW-5A,MW-6A,MW-513,and MW-5C, and was generally the same as previous quarters In the remaining wells • The core of the MTBE plume Is situated over the former UST areas (MW-2, MW-4 and MW-7), the plume extends south to well MW-6 and southwest to well MW-5 (Figure 8) During the fourth quarter 2005, MTBE was detected at significant concentrations In wells near the former UST area(MW-I through MW-4 and MW-7)and in hydrogeologic unit HU 1 and HU2 at the more distal wells MW-5 and MW-6, however MTBE was non-detect In deeper hydrogeologlc units of wells MW-5 and MW-6 • 1,2-DCA was detected In five samples collected from the former UST area Other fuel additives (TBA, ETBE and TAME) were also detected near the former UST area • The vertical extent of Impacted ground water at the western and southern edge of the site are defined by well MW-5, and to a lesser degree by MW-6 The vertical extent of Impacted ground water at the former UST area has not been defined,extending beyond the total depth of well MW-7E i i • The lateral extent of shallow, Impacted ground water towards the west and southwest, down-gradient of the UST area, has not been defined Advanced GeoEnvironmental,Inc i I