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1 14 January 2004 • AGE-NC Project No. 97-0327 Page 3 of 5 June 2003 and the September 2003 ground water monitoring events. Ground water flow direction for the area bound by wells MW-1 through MW-4 was inferred as toward the south at a gradient of 0.001 ft/ft. 1 3.2. ANALYTICAL RESULTS OF MONITORING WELL WATER SAMPLES A total of four ground water samples were submitted to Castle Analytical Laboratory(CAL),a DHS- certified laboratory, for analysis. TPH-g was detected in a water sample collected from well MW-2 at a concentration of 85 micrograms per liter(µg/]).TPH-d was detected in a water samples collected from wells MW-1 and MW-2 at concentrations of 51 ug/l and 85 pg/l, respectively. i Xylene was the only BTEX compound detected from well MW-2 at concentration of 1.3 µg/1. Utilizing EPA Method 8260M, MTBE was detected in a sample collected from MW-2 at a concentration of 16 ug/l. 1,2-DCA was detected in samples collected from wells MW-1,MW-2 and MW-4 at concentrations of 1.5 µg/l, 0.85 µg/l and 1.3 iug/l, respectively. I . No other fuel components were detected above the laboratory reporting limits. Analytical results of the ground water samples are summarized in Table 3. The laboratory reports (Castle Analytical Laboratory Reference No. 615 1) and chain-of-custody forms are presented in Appendix B. 1 4.0. SUMMARY AND CONCLUSIONS The implications from the September 2003 ground watermonitoring event are as follows: • The decrease of ground water elevation of approximately 1.73,feet between June 2003 and September 2003 is probably due to seasonal fluctuation. • Ground water flow direction at the site'was inferred to be toward the south at a gradient of 0.001 ft/ft or less; previous ground water monitoring events at the site have determined.the prevalent ground water flow direction to be towards the south-southeast. • Due to the low gradient at the site, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could have modified ground water flow direction. • The ground water elevation at the site was within the screened intervals of wells MW-1, MW-2, MW-3 and MW-4, which should yield samples fully representative of shallow ground water conditions. ' Advanced CeoEnvlronmental,Inc.