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• 25 January 2005 AGE-NC Project No 99-0559 Page 4of10 screened interval of these wells At the time of the December 2004 monitoring event, ground water flow within the interval of HU 1 and HU2 wells was Inferred to be toward the west or northwest (Figure 3), at a gradient of approximately 0 02 ft/ft HU3 and HU4 In the wells representing HU3 and HU4, the depth to ground water ranged from 63 71 to 64 47 feet btoc The ground water elevation was calculated between 39 11 feet (MW-5/6) and 39 24 feet (MW-7) below MSL, the ground water elevation from wells in this hydrologic Interval Increased 1 7 feet since the last quarterly monitoring event Ground water was inferred to be flowing north at a gradient of 0 001 ft/ft (Figure 4) HU5 Within the upper portion of HU5 (Upper HU5), screened between 125 and 135 feet bsg, ground water elevation ranged between 39 05 feet(MW-6) and 39 32 feet(MW-7)below MSL, the ground water elevation increased 19 feet since the last monitoring event Ground water at the former UST release was inferred to be flowing toward the north at a gradient of 0 002 ft/ft (Figure 5) Within the lower portion of HU5 (Lower HU5), screened between 148 and 160 feet bsg, ground water elevation ranged between 63 59 feet(MW-5)and 38 96 feet(MW-6)below MSL, the ground water elevation Increased 2 2 feet since the last monitoring event Ground water was determined to be flowing toward the north at a hydraulic gradient of 0 003 ft/ft (Figure 6) HU6 In the wells representing HU6,the depth to ground water ranged between 63 83 and 64 67 feet btoc The ground water elevation was calculated between 39 23 feet(MW-5)and 39 64 feet(MW-7) below MSL, the ground water elevation from wells In this hydrologic units increased 3 1 feet since the last quarterly monitoring event Ground water was inferred to be flowing toward the north at a hydraulic gradient of 0 002 ft/ft (Figure 7) 2 4 ANALYTICAL RESULTS OF GROUND WATER SAMPLE ANALYSIS Twelve ground water samples were analyzed by CTEL for the chemical constituents referenced in Section 2 2 The following is a summary of the analytical results HU1 and HU2 HU1 and HU2 wells were dry or contained Insufficient water to sample this quarter, however, free product was balled out of wells MW-1 through MW-3 HU3 and HU4 TPH-g was detected in wells MW-5B, MW6B and MW-7B at concentrations of 710 micrograms per liter(µg/1), 150 µg/1 and 4,100 µg/1, respectively Various BTEX compounds were detected in samples MW-6B and MW-7B at maximum concentrations of 1,500 p.g/1 benzene, 1,700 �tg/l toluene, 100 µg/1 ethyl-benzene and 470 µg/1 total xylenes in sample MW-7B The fuel additive MTBE was detected in samples MW-5B,MW6B and MW-7B at concentrations of 710µg/1, Advanced Geohnvironmental,Inc