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' 18 June 2001 AGE-NC Project No 99-0559 ' Page 3 of 5 ' 3.0, FINDINGS Ground water elevation, flow direction and gradient were determined from field data collected on ' 26 April 2001, the contaminant unpact to ground water was quantified by the ground water sample laboratory analytical data 3 1 GROUND WATER ELEVATION AND GRADIENT ' The ground water elevation on 26 April 2001 ranged from 23 89 to 24 06 feet below mean sea level (MSL) The top of the ground water table occurred within the screened intervals of the wells The ' ground water elevations decreased,significantly in wells MW-1 and MW-3,between this monitoring event and the January 2001 monitoring event ' Ground water was determined to be flowing to the west with a hydraulic gradient of 0 002 The ground water contours are depicted on Figure 3 ' 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLE ANALYSIS TPH-g was detected in the ground water samples collected from all wells at concentrations ranging from 20,000µg11 in sample MW-1 to 21 0,000µg/1 in sample MW-2 rBenzene was detected in all four samples at concentrations ranging 3,800µg/l in sample MW-1 to 32,000,ug/1 in MW-2 The remaining BTEX compounds ranged form 220µg/1 of toluene in MW-1 to 41,000µg/1 of toluene in MW-2 MTBE was detected in all four well samples utilizing EPA Method 8020 at concentrations ranging from 5,200,ug/l in MW-1 to 170,000 1,zg/1 in MW2 and MW-4 MTBE concentrations detected by EPA Method 8260 Modified ranged from 4,800 µg/1 in sample MW1 to 180,000 µg/l in sample MW-2 The remaining fuel oxygenates were not detected in the samples, however, due to necessary dilution of the samples, the detection limits ranged from 130µg/1 for TAME, ETBE and TBA in MW-1 to 25,000µg/1 for TBA in samples MW-2 and MW-4 Methanol detection limits were 1,300,0004g/1 and ethanol detection limits were 250,000µg/1 ' The analytical results of water samples are summarized in Table 2 The laboratory reports (MAI Laboratory I D Nos 66329 to 66332), quality assurance and quality control (QA/QC) reports and chain-of custody forms are included in Appendix B Advanced GcoEnvmronmental,Inc