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1 ' 20 March 2006 AGE-NC Project No 95-0130 tPage 5 of 13 The measured depths to ground water from the purged wells were between 42 91 and 45 01 feet below the top of the well casings Ground water elevations were calculated to be between 27 36 feet (MW-1)and 28 85 feet(MW-7B) below mean sea level (MSL) Generally, ground water elevation at the site decreased an average of 0 21 feet between the September 2005 and the December 2005 ground water monitoring events First zone(HUI -40 to 55 feet) ground water flow direction at the Top Filling Station was inferred to be towards the north-northeast at an approximate gradient of 0 02 ft/ft, Second zone(HU2 and HU3 - 55 to 85 feet bsg)ground water flow direction at the Top Filling Station was inferred to be northeast at an approximate gradient of 0 002 ft/ft or less The First and Second zone ground water elevation data collected during the December 2005 ground water ' monitoring event is depicted on Figures 3 and 4, respectively 2 4 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES On 06 December 2005, a total of fifteen ground water samples were submitted to CTEL, a DHS- certified laboratory, for the analysis referenced in Section 2 3 TPH-g was detected from wells MW-6(B-E), MW-7(B-D), VW-1C, VW-2A and VW-3A at • concentrations as high as 150,000 micrograms per liter(pg/l)in the sample collected from MW-713 The estimated extent of First Zone (between 35 and 55 feet bsg) and Second Zone (between 55 and 80 feet bsg) dissolved TPH-g are depicted in Figures 5 and 7, respectively ' Benzene was detected in the above monitoring samples les and well MW-3 at a maximum p concentration of 27,000 µg/l (MW-7B) Other BTEX compounds were detected in the above ' monitoring well samples at concentrations as high as 20,000 µg/1 toluene from MW-7B, and 2,900 µg/1 ethylbenzene and 14,400 µg/l total xylenes from VW-I C MTBE was detected in ground water samples collected from wells MW-6(B-D),MW-713,VW-2A and VW-3A at concentrations as high as 18 pg/l (VW-3A) The estimated extent of First Zone and ' Second Zone dissolved MTBE are depicted in Figures 6 and 8, respectively 1,2-DCA was detected in ground water samples collected from wells MW-6 (B-E),MW-7 (B-D), ' MW-8, VW-1C, VW-2A and VW-3A at concentrations as high as 180 µg/l (MW-7B) No other fuel components were detected in the ground water samples Previous and current analytical ' results of ground water monitoring well samples are summarized in Tables 3 and 4 The laboratory reports(CTEL Laboratory I D 0512-048)and chain of custody forms are presented in Appendix B, GeoTracker confirmation pages of the submitted laboratory electronic deliverable format(EDF)files and depth to water measurements are included in Appendix C Advanced GeoEnvironmentai,Inc