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05 February 2001 i., AGE-NC Project No.,98-0468 ' Page 6of7 There were no reported detections of BTEX compounds,TPH-d or TPH-g in,any of the ground water, ' samples analyzed during the November 2000 monitoring event(Table 2). MTBE was reported in the ground water sample collected from monitoring well MW-4, MW-6 and ' MW-8 at concentrations of 270 microgram per liter(ug/l), 54µg11 and 2.3 mg/l,respectively,by EPA Method 8260. The reported detections of MTBE in the samples•exceed the DHS - established maximum contaminant level (MCL) of 13,/.cg/1 for MTBE in ground water. " Ethanol was detected in well MW-5 at a concentration of 5.9 ug/1 and TBA was detected in well MW-4 at a concentration of 5.3 ,ug/l. There were no'reported'detections of any other fuel oxygenating compounds. 4.0. SUMMARY/CONCLUSIONS ' The following summary points and conclusions were drawn from the results of the site investigation: " • During this monitoring event, the depth:to ground water at the,site ranged-.from 10.42 to ' 13.28 feet below top of well casings.(btoc) (Table 1)'. Ground water elevation at the site ranged from 3.53'to 4.17 feet below mean sea level (MSL) in well MW-3 and MW-4, :. respectively. ' Ground water elevation in the monitoring wells decreased an average of 1.2 feet since the' previous monitoring event. ' Based on ground water elevation data, ground water flow direction is inferred to be toward ; the north. Groundwater gradient for November 2000 was calculated to be 0.012. • MTBE was-'detected in the soil samples collected from borings MW6 and MW8 at., concentrations as high as 95 mg/kg. • MTBE was also detected in the ground water samples collected from MW-4, MW-6 and MW-8. • The down-gradient extent of MTBE-impacted ground water has been delineated to the DHS- ' established secondary maximum contaminant level(MCL) of 13 µg11 for MTBE in ground ' water. 5:0. RECOMMENDATIONS ' Based• upon data collected at the site, AGE recommends continuation of the quarterly groundwater monitoring program, "scheduled to be conducted,in February 2001. _ Advanced GcoEnvironmental,Inc.