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i 07 January 1998 AGE-NC Project No 95-0130 Page 3 of 5 During the September 1997 quarterly ground water event,ground water was between 2 49 and 12 80 feet above the screened Intervals in monitoring wells MW-1 through MW-5 Therefore, the wells are "drowned", and may not be fully representative of ground water conditions near the top of the saturated zone, where fuel hydrocarbons would be expected to have the greatest impact In September 1997, the gradient was calculated to be 0 006 ft/ft (approximately 32 feet per mile) with a ground water flow direction generally toward the northeast From January 1995 up to the current monitoring period, the ground water flow direction at the site has remained relatively constant 32 REVISIONS TO JANUARY, MARCH AND JUNE 1997 RELATIVE GROUND WATER ELEVATION MAPS The ground water elevation results produced after the monitoring well survey indicated a ground water flow direction towards the northeast on 25 September 1997 Therefore, relative ground water elevation maps for January, March and June 1997 were revised utilizing the new well survey data and also indicated a northeast ground water flow direction The revised relative ground water elevation maps are in Appendix D 33 LABORATORY RESULTS OF GROUND WATER SAMPLES TPH-g was detected in ground water samples collected from wells MW-2, MW-3, MW-5, VW-1C, VW-2A and VW-3A The highest detected concentration of TPII-g was reported from VW-1C at 310,000 yg/l (micrograms per liter or parts per billion ppb), while the lowest was reported from I MW-2 at 150 ppb 1 Benzene was detected in ground water samples collected from wells MW-2 through MW-5,VW-IC, VW-2A and VW-3A The highest detected concentration of benzene was reported from VW-1C at a concentration of 50,000 ppb, while the lowest was reported from MW-4 at 0 92 ppb Toluene, ethylbenzene and xylenes were detected in samples collected from wells MW-2 through MW-5, VW-IC, V W-2A and VW-3A The highest concentration was reported from VW-IC at 55,000 ppb, while the lower concentrations were reported from MW-2 and MW-4 at 2 5 ppb MTBE was detected utilizing EPA method 8020 in ground water samples collected from MW-3, VW-IC,V W-2A and VW-3A The highest concentration of MTBE utilizing 8020 was reported from VW-3A at a concentration of 3,600 ppb, while the lowest concentration was reported from MW-3 at 36 ppb MTBE was confirmed utilizing EPA method 8260 in ground water samples collected from MW-3, VW-IC, VW-2A and VW-3A The highest concentration of MTBE utilizing 8260 was Advanced GcoEnvlronmental,Inc