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' 09 June 2004 AGE-NC Project No 98-0452 ' Page 3 of 5 ' datum NAVD 88 The results of the monitoring well survey are contained in Table 1 The surveying report (Morrow Surveying) is presented in Appendix B ' 3.0. FINDINGS ' Ground water elevation and flow direction were calculated from field data The impact to ground water was assessed by laboratory analysis of the ground water samples ' 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION ' The elevation of ground water in each well was calculated by subtracting the depth to ground water from the surveyed well head elevations (Table 1) Depths to ground water for the December 2003 monitoring event ranged from 4 51 feet to 5 45 feet below the tops of the well casings Ground water Ielevations at the site ranged from 0 43 feet (MW-2) to 0 83 feet (MW-3) above mean sea level (MSL) The ground water gradient was calculated to be approximately 0 004 foot/foot with a flow ' direction toward the west-northwest(Figure 3) Average depth to ground water was 4 99 feet below the tops of the well casings and dropped an average of 0 28 feet between the September 2003 and December 2003 monitoring events ' Depths to ground water for the March 2004 monitoring event ranged from 4 25 feet to 5 06 feet below the tops of the well casings Ground water elevations at the site ranged from 1 02 feet(MW-2) to 1 10 feet (MW-1) above mean sea level (MSL) The ground water gradient was calculated to be approximately 0 0009 ft/ft with a flow direction toward the northwest(Figure 4) Average depth to ground water was 4 58 feet below the tops of the well casings and rose an average of 0 41 feet between the December 2003 and March 2004 monitoring events 3 2 ANALYTICAL RESULTS OF WATER SAMPLES Ground water samples from the December 2003 monitoring event had detections of TPH-g and MTBE TPH-g was detected at a concentration of 200 micrograms per liter(µg/i)in monitoring well MW-2 which is down gradient as well as partly cross-gradient of the former UST area MTBE was detected in the samples taken from MW-2 and MW-3 at concentrations of 190 µg/1 and 23 µg/1, respectively Figure 5 shows approximate hydrocarbon impact to ground water for the December monitoring event Samples from the March 2004 monitoring event had no records of TPH-g MTBE was detected at • concentrations of 8 1 µg/1 and 19 µg/1 in MW-2 and MW-3, respectively Figure 6 shows Advanced CeoEnvironmental,Inc I