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r09 April 1999 AGE-NC Project No 96-0229 Page 3 of 5 I Ground water monitoring data collected in the area of wells MW-1 through MW-10 indicated that the ground water flow direction was generally toward the northeast at a gradient of 0 002 ft/ft, or approximately 11 feet per mile (Figure 3) Ground water was approximately 2 to 3 feet above the screened intervals in monitoring wells MW-3 and MW-4, ground water was approximately 20 to 22 feet above the screen intervals at MW-1 and MW10-B Therefore these wells are "drowned", and yield samples fully representative of deeper screened ground water that may be under confined or Isemi-confined conditions 32 LABORATORY RESULTS OF GROUND WATER SAMPLES A total of eleven ground water samples were submitted to a DHS-certified laboratory in January ' 1999 TPH-g was detected in water samples collected from wells MW-1 through MW-3, MW-6, MW-7 and MW-8 at concentrations ranging up to 120,000 micrograms per liter (fig/1) BTEX compounds were detected in ground water samples collected from wells MW-1 through MW- 4,MW-6 and MW-7 at concentrations ranging as high as 17,000,ug/l (toluene, MW-6) The greatest benzene concentration was detected from well MW-6 at a concentration of 5,700 ,ug/1 MTBE was detected from wells MW-1, MW-4, MW-5, MW-7 and MW-8 utilizing EPA Method 8020 at concentrations as high as 910,ugll, MTBE was confirmed utilizing EPA Method 8260 from wells MW-1, MW-4, MW-6, MW-7 and MW-8 at concentrations ranging as high as 600 ,ug/l, TAME and TBA were detected from wells MW-7 and MW-8 at concentrations ranging as high as 30 ,ug/l No other fuel oxygenated additives were detected above laboratory reporting limits from the analyzed samples Analytical results of the ground water samples are summarized in Table 2 The laboratory reports (Castle Analytical Laboratory Reference No 2000 and McCampbell Analytical Inc I D No 02426 through 02436) and chain-of-custody forms are presented in Appendix B 4.0. SUMMARY AND CONCLUSIONS Based on the results of ground water monitoring and sampling activities performed in January 1999, AGE concludes • Groundwater monitoring data collected in the area of wells MW-1 through MW-10 indicated a ground water flow direction generally toward the northeast at a gradient of 0 002 ft/ft 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 Advanced GeoEmironmental,Inc