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'y21 November�No� 2001 AGE-NC Project No 95-0167 ' Page 3 of 4 BTEX compounds were detected in the water samples collected from monitoring wells MW-1 and MW-2 at concentrations as high as 3,700 µg/l, 4,300 µg/1, 730 µg11 and 3,700 gg/l, respectively MTBE was detected in MW-2 at a concentration of 8 8 gg/1 by EPA Method 8020 MTBE was detected by EPA Method 8260 Modified in samples from wells MW-1 and MW-2 at concentrations of 62 µg/l and 6 5 pg/l, respectively No other oxygenates were detected in the ground water t samples u Analytical results of water samples collected in August 2001 are summarized on Table 2 and ' Table 3 The laboratory report (MAI Lab IDs 76164 through 76169), QA/QC report and chain-of- custody form are included in Appendix B Figure 4 depicts the estimated areal distribution of impacted ground water containing TPH-g for 24 August 2001 4.0. SUMMARY AND CONCLUSIONS Data collected at the site indicates that '• * The ground water flow direction during this monitoring event was toward the northwest at a gradient of 0 020 ft/ft Ground water flow at the site has historically been towards the northwest Groundwater flow direction was not well defined near the former UST pit during ' the August 2001 monitoring event • Relatively high concentrations of TPH-g and BTEX occur in ground water in the area of monitoring wells MW-1 and MW-2 • MTBE is present in monitoring wells MW-1 and MW-2 at concentrations as high as 62 gg/l L' (sample MW- 1)• The contaminant plume appears to be confined to the general areas near MW-1 and MW-2 Petroleum hydrocarbons were not detected in perimeter wells MW-3, MW-4, MW-5 and ' MW-6 ' 5.0. RECOMMENDATIONS Based on present site conditions, AGE recommends continued quarterly ground water monitoring at-the site The-next monitoring event should be scheduled for November 2001 - - - Advanced GeoEnvironmentel,Inc