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i 1 30 Apn1 1999 1 AGE-NC Project No 98-0450 Page 3 of 5 3.0. FINDINGS Ground water elevation, flow direction and gradient were calculated from field data, presented in Appendix B Hydrocarbon impact to ground water was determined by laboratory analysis, the laboratory report is included in Appendix C 3 1 RELATIVE GROUND WATER ELEVATION AND GRADIENT ' The measured depths to ground water from all six ground water monitoring wells ranged from 44 77 feet to 45 42 feet below the tops of the well casings The ground water elevation for the monitoring event ranged from 0 27 feet to 0 60 feet above msl The ground water elevation data is presented in Table I Ground water elevations were plotted and contoured on a scaled site map The ground water elevation data for the wells during the February 1999 ground water monitoring event is ' depicted in Figure 3 Generally,ground water monitoring data collected at the site indicated a southerly ground water flow direction Based on a southerly flow direction, well MW-5 is in the down-gradient position from the former UST area The ground water gradient was calculated to be approximately 0 0035 or 18 6 feet per mile for the February 1999 ground water monitoring event 3 2 LABORATORY RESULTS OF GROUND WATER SAMPLES TPH-g, TPH-d, BTEX and MTBE were detected in the ground water samples collected from all the wells ' TPH-g concentrations ranged from 85,000 micrograms per liter(µg/l)in the BMW-4 sample to non- detection in the MW-5 sample TPH-d concentrations ranged from 6,800 µg/l (BMW-4) to non- detect(MW-5) Benzene concentrations ranged from <0 5 µg/l (MW-5) to 2,700 µg/1 (BMW-4) MTBE concentrations ranged from<1 0 µg/1(BMW-3) to 710 µg/l (BMW-4) as analyzed by EPA method 8260 Modified and up to concentrations of 850µg/l in well BMW-4 as analyzed by EPA method 8020 TAME, TBA, DIPE and ETBE were not detected by laboratory analysis of any of the ' ground water samples The laboratory report(McCampbell Analytical Inc Laboratory I D No 03970 to 03975), Quality ' Assurance and Quality Control reports (QA/QC) and chain-of-custody form are presented in Appendix C The results of the analysis are contained in Table 2 and Table 3 Advanced GcoEn,ironmental,Inc 1