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07 December 2000 AGE-NC Project No 97-0301 Page 3 of 4 , events, decreasing ground water elevation has been observed at the site since the December 1999 ' ground water monitoring event The ground water elevation data for MW-1, MW-2, MW-3 and MW-4 during the September 2000 ground water monitoring event is depicted in Figure 3 Ground water flow direction for the area bound by wells MW-1, MW-2, MW-3 and MW-4 was generally ' toward the north-northeast at a gradient of 0 001 ft/fl, or approximately 5 feet per mile (Figure 3) ' 3 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES ' A total of four ground water samples were submitted to a DHS-certified laboratory in September 2000 TPH-g was detected in water samples collected from wells MW-1 and MW-4 at concentrations of 38,000 and 63 micrograms per liter(/,cg/1), respectively, TPH-d was detected in the water sample ' collected from MW-1 at a concentration of 4,500µg11 BTEX compounds were detected in the ground water samples collected from wells MW-1 and MW- ' 4 at concentrations ranging as high as 5,200 4gll (MW-1, xylenes) Benzene was detected in the water sample collected from well MW-1 at a concentration of 2,100 µg/1 Fuel oxygenated compounds were not detected above the respected laboratory reporting limits Analytical results of the ground water samples are summarized in Table 2 The laboratory reports (Castle Analytical Laboratories Reference No 3217 and McCampbell Analytical Inc I D No 47851 ' through 47854) and chain-of-custody forms are presented in Appendix B ' 4.0. SUMMARY AND CONCLUSIONS ' The implications from the September 2000 ground water monitoring event are as follows • Ground water flow direction at the site appeared to be oriented generally towards the north- northeast at a gradient of 0 001, 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 greatly modify 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 yield samples fully representative of shallow ground water 1conditions • Ground water elevations decreased at the site an average 3 30 feet between the June 2000 and September 2000 ground water monitoring events, the decrease of ground water elevations ' Is probably due to the seasonal fluctuation pattern • The core of the dissolved petroleum hydrocarbon plume appears to be located in the area of Advanced GeoEnvironmental,Inc i