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i 03 October 2001 AGE-NC Project No 99-0559 IPage 3 of 4 3 1 GROUND WATER ELEVATION AND GRADIENT The ground water elevation on 10 August 2001 ranged from 30 28 to 30 78 feet below mean sea level (msl) The value for well MW-2, 30 28 feet below msl, was not corrected for the presence of free-product,the skimmer was removed from the well full of product and no correction measurement was collected The top of the ground water table occurred within the screened intervals of the wells The ground water elevations decreased significantly at the site over the last quarter Ground water was determined to be flowing to the west-northwest with a hydraulic gradient of 0 005 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 the wells at concentrations ranging from 16,000µg11 in sample MW-1 to 120,000,ug/l in sample MW-4 Benzene was detected in all three samples at concentrations ranging 1,700 ,ug/1 in sample MW-1 to 2 1,000,ug/1 in MW-4 The remaining BTEX compounds ranged form 220,ug/l of toluene in MW-1 to 19,000 gg/l of toluene in MW-4 MTBE was detected in all well samples utilizing EPA Method 8020 at concentrations ranging from 4,200µg/l in MW-1 to 11 0,000,ug/l in MW-4 MTBE concentrations detected by EPA Method 8260 IModified ranged from 4,300,ug/1 in sample MW i to 170,000µg/1 in sample MW-4 The remaining fuel oxygenates were not detected in the samples,however, due to necessary dilution of the samples, the detection limits ranged from 100µg/l for TAME, ETBE and TBA in MW-1 to 13,000 gg/l for TBA in samples MW-4 Methanol detection limits were as high as 1,300,000yg/l and ethanol detection limits were 130,0004g/1 I 1 summarized in Table 2 The laboratory reports MAI The analytical results of water samples are summon e ry ep ( Laboratory I D Nos 74743 to 74745), quality assurance and quality control (QA/QC) reports and chain-of-custody forms are included in Appendix B 3 3 FREE PRODUCT MEASUREMENTS/REMOVAL/DISPOSAL Free-product thickness measurements and removal were performed in well MW-2 The amount of • free-product recovered was not quantified The current free product thickness was not measured However, the passive skimmer was consistently one-quarter full of product when measured Advanced GeoEnvironmental,Inc