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I, 11 December 2000 AGE-NC Project No 97-0312 Page 3 of 4 3 1 GROUND WATER ELEVATION AND GRADIENT Ground water elevation decreased an average of 7 08 feet at the site since the 20 March 2000 ' monitoring event Ground water flow direction was inferred to be northwesterly at a gradient of 0 005 ft/ft The flow direction changed approximately 100 degrees counter-clockwise compared to the previous monitoring events Figure 4 depicts the ground water elevation contours for June 2000 ' Static ground water was approximately 1 foot above the screened interval in UST-5,7 feet above the screened interval of UST-6, 10 feet above the screened interval of UST-2, UST-3 and UST-4, and ' approximately 30 feet above the screened interval In UST-1 - ' 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g,benzene,toluene,and ethylbenzene were detected in the water sample collected from UST-5 ' at concentrations as high as 560 micrograms per liter (µg/1), 26 µg/l, 1 9 µg/1, and 2 4 Rg/1 respectively TPH-g, benzene, and xylenes were also detected in lower concentrations in samples collected from UST-1 and UST-2 TPH-d was detected in the samples collected from UST-1,UST-2, UST-3,and UST-5 at concentrations as high as 780 Ag/1(UST-1) Petroleum hydrocarbons were not detected in wells UST-4, UST-6 or the domestic wells MTBE was detected In UST-2 and UST-6 at concentrations of 2 6 µg/1 and 1 1 µg/l, respectively Oxygenates were not detected in the water samples collected from wells UST-1,USI-3,UST-4,and 1 UST-5,or the domestic well samples DW-1 and DW-2 1,2-dichloroethane(1,2-DCA)was detected in the samples collected from UST-5 and UST-6 at concentrations of 910 µg/1 and 2 1 µg/1, respectively 1,1-dlchloroethane(1,1-DCA)and tetrachloroethene(PCE)was detected in the sample ' collected from the small domestic well (DW-1) at concentrations of 13 µg/1 and 6 4 µg/1, respectively Vinyl chloride was detected In sample UST-1 at a concentration of 1 6 µg/1 The laboratory report (MAI sample Nos 40401- 40408) and chain-of-custody forms are included in ' Appendix B Analytical results of water samples collected in June 2000 are summarized on Table 2 The analytical results of all water samples are summarized on Tables 3 1 J 4.0. DISCUSSION AND CONCLUSIONS y ' Based upon data collected from the site, AGE concludes the following Ground water elevation decreased more than 7 feet at the site between the March and June ' 2000 monitoring events The Inferred ground water flow direction has change approximately 100 degrees counter clockwise from a northeasterly direction to a northwesterly direction Advanced GeaEnvironmental,Inc