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I 13 July 1999 AGE-NC Project No 95-0142 Page 3 of 4 I3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in samples collected from wells VW-1 through VW-4 at concentrations ranging ' from 81 micrograms per liter (µg/1) to 160,000 µg/1 TPH-g was detected in well MW-6 at a concentration of 38,000 µg/l, respectively ' BTEX compounds were detected in all the samples collected from the monitoring wells except MW- 4 and MW-5 BTEX compounds were detected in samples from each vapor well at concentrations ' as high as 36,000 ,ug/l (toluene, VW-1) Benzene concentrations ranged from 19 µg/l (VW-4) to 21,000µg/1 (VW-1) BTEX compounds were detected in the sample from MW-6 at concentrations of 2,300µg/l benzene, 800µg/l toluene, 1,400 µg/1 ethylbenzene and 6,200 /.cg/l xylene ' MTBE was the only oxygenated compound detected in water samples collected from the site MTBE was detected by EPA method 8260 Modified in the ground water samples collected from wells MW- 5, MW-6, VW-1, VW-2, VW-3 and VW-4 at concentrations of 1 7 4g/1, 33 µg/1, 500µg/1, 5 1 µg/1, 66µg/l, 6 3 µg/l, respectively ' Analytical results for the ground water samples analyzed by EPA Methods 8015 Modified and 8020 are summarized in Table 2 Analytical results for the ground water samples as analyzed by EPA Method 8260 Modified are summarized in Table 3 The laboratory report (MAI Laboratory I D ' Nos 14167 through 14173), quality assurance and quality control (QA/QC) report and chain-of- custody form are included in Appendix B 4.0. CONCLUSIONS ' Based on data collected from the site, AGE concludes ' Ground water flow direction varied generally toward the east to northeast Ground water levels were above the screened intervals of ground water monitoring wells ' MW-1, MW-2, MW-3, these wells may not be adequate to characterize the shallow dissolved-phase hydrocarbon plume • Detectable concentrations of hydrocarbons were not present in samples collected from the ' down gradient wells MW-4 and MW-5, although MTBE was detected in the sample MW-5 i The highest concentration of dissolved petroleum hydrocarbons continues to be in the area ' of the documented release (vapor well VW-1), located immediately adjacent to the former TK1-90 UST ' Advanced GeoEnvironmental,Inc 1