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. 31 January 2000 AGE-NC Project No 95-0184 I Page 3 of 4 u , MW-3,with ground water approximately 22 to 23 feet above the screened interval and the remaining wells The inferred ground water flow direction in November 1999 was toward the east to northeast with a gradient of approximately 0 003 ft/ft (Figure 3) for both data'sets A steeper gradient was T ' observed in the vicinity of wells VW-2, VW-3 and VW-4 ' 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' TPH-g was detected in all sampled wells at concentrations ranging from 470 parts per billion (ppb, ' reported as micrograms per liter,,ug/1) in MW-7 to 200,000 ppb in VW-2B TPH-d was detected in the sample from MW-4 at a concentration of 4,800 ppb IBenzene was also detected in all wells sampled at concentrations ranging from 25 ppb,in MW-3 to 42,000 ppb in VW-213 The remaining BTEX compounds were detected at concentrations ranging from 4 1 ppb of ethylbenzene in MW-3 to 43,000 ppb of toluene in VW-5B DIPE and TBA were detected in the sample from MW-1 at concentrations of 8 ppb and 37 ppb, respectively, and in MW-3 at concentrations of 1 2 ppb and 8 1 ppb, respectively MTBE was detected in the samples collected from MW-h and VW-213 at concentrations of 2 5 ppb and 520 ppb, respectively 1,2-D;chloroethane (DCA) was detected in wells MW-3, MW-4 and VW-2B at ' concentrations of 1 4 ppb, 690 ppb and 1,400 ppb, respectively Eight additional constituents were detected by EPA Method 8260 at concentrations as high as 3,900 ppb (1,2,4-trimethylbenzene, VW- 513) ' Analytical results are summarized on Tables 2 and 3 The laboratory report re le Nos (MAI sample I2611?-26121) and chain-of-custody forms are included in Appendix B ' 4,0. DISCUSSION AND CONCLUSIONS Based upon data collected from the site, AGE concludes the following ti ' Petroleum hydrocarbons were detected in each well sampled, at concentrations as high as 200,000 ppb No free product was measured during this sampling e,,ent, however, the majority of the well screens are drowned and would not necessarily indicate the presence of - free product • MTBE was detected in two wells during the November 1999 monitoring event MTBE has been detected at significant concentrations during previous monitoring events, but may not have been detected in several wells due to high laboratory reporting limits • Ground water levels are as high as 22 to 23 feet above the- screened interval The hydrocarbon concentrations detected in these `drowned' wells may not be representative of ' Ad�antdCiuFmiroununlal fnc