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h } 1 ' 07 May 2004 AGE-NC Project No 98-0534 ` ' Page 7 of 14 sampling event Ground water levels averaged 7 8 feet below the tops of the well casings ' (above the screened interval), ground water flow direction at the site was/inferred to be towards the north and south away from an east-west trending hydraulic saddle at the main UST area,with a gradient of approximately 0 009 to 0 01 feet/feet North of we11,MW-4,the ' water table was inferred to be rising with a gradient of 0 05 feet/feet, resulting in the ` formation of an elongated depression trending east-west located between wells MW-5 and MW-6 TPH-g was detected in the ground water samples collected from wells MW-3,MW- 4, MW-6 and MW-7 at concentrations 'of 120 µg/l, 110 µg/l, 90 µg/1 and 800 µg/l, respectively Toluene was the only BTEX compound detected in the ground water samples, ' at a maximum concentration of 15 µg/1 in MW-4 TPH-d was not detected in any of the samples MTBE was detected by EPA Method 8020 in the ground water samples from wells MW-3, MW-4, MW-6, MW-7 and MW-8 at concentrations of 6 2 µg/1, 14 gg/l, 30 µg/1, L ' 19 µg/1 and 2 4 µg/l,respectively, MTBE was detected by EPA Method 8260 in the samples from wells MW-3, MW-4, and MW-6 at concentrations of 7 0 µg/l, 20 µg/1 and 43 µg/1, respectively No other fuel oxygenates were detected In any of the analyzed'samples Ground ' water elevations are summarized In Table 1, analytical results of ground water samples are summarized in Table 2 Results of the January 2002 ground water monitoring event were 10 reported in Quarterly Report - Is1 Quarter 2002, dated 03 April 2002, prepared by AGE ./ • 14 June 2002 - ground water levels were measured at MW-1 and MW-3 through MW-8 Ground water monitoring well MW-2 was not readily accessible or located during the sampling event Ground water levels averaged 10 8 feet below the tops of the well casings (within the screened interval), ground water flow direction at the site was inferred to be towards the northeast away from the former UST area, with a gradient of approximately, 0 009 to 0 01 feet/feet The ground water elevation of monitoring well MW-4 appeared anomalously low, out of the range of the surrounding wells by 1 foot, and further failed to recharge after purging, therefore the data from that well was not used to map the ground ' water elevation TPH-g was not detected in the ground water samples collected from wells a Toluene was the only BTEX compound detected in the ground water samples,at a maximum concentration of 1 1 µg/1 in MW-4 TPH-d was detected in the ground water samples collected from wells MW-4 and MW-6 at concentrations of 130 µg/I and 53 gg/l, respectively MTBE was detected by EPA Method 8260 in,the samples from wells MW:3,. MW-4, MW-6,MW-7 and MW-8 at concentrations of 6 9 µg11, 18 µg/1, 150 µg11, 0 62 µg/1 ' and 5 3 µg/l, respectively ETBE was detected by EPA Method 8260 In the samples from well MW-6 at 4 2 µg/1 TBA was detected by EPA Method 8260 in the samples from well MW-4 at 21 µg/1 No other fuel oxygenates were detected in any of the samples Ground Iwater efevations are summarized in Table 1, analytical results of ground water samples are summanzed in Table 2 Results of the June 2002 ground water monitoring event were ' reported in Quarterly Report-2nd Quarter 2002, dated 03 August 2002,prepared by AGE I • 02 October 2002- groundwater levels were measured at MW-1 and MW-3 through MW-8 l Advanced GeoEnvironmental,Inc F