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05 November 1997 AGE-NC Project No 96-0249 ' Page 5 of 7 ' was not detected in any of the analyzed soil samples Analytical results of soil samples are summarized in Table 1 -Analytical Results of Soil Samples The Iaboratory report (MAI Lab I D No 81153 to 81165) and chain-of-custody are included in Appendix B 44 ANALYTICAL RESULTS OF GROUND WATER SAMPLES A total of four grab ground water samples were submitted to MAI for analysis of TPH-g, TPH-d, BTEX and MTBE, P3-H20 was analyzed for volatile aromatics in accordance with EPA method 8260 TPH-g was detected in ground water samples P1-H20 through P4-H20 at concentrations between 8,200 parts per billion (ppb, reported as micrograms per liter or ,ug/l) and 120,000 ppb, TPH-d was detected in ground water samples collected from Pl-H20 through P4-H20 at concentrations between 5,700 ppb and 530,000 ppb, BTE&X were detected in all four ground water samples at concentrations as high as 19,000 ppb Benzene concentrations were detected at concentrations between 460 ppb and 17,000 ppb in the ground water samples Napthalene and 1,3,5- 1 Trimethylbenzene were detected in sample P3-H20 at concentrations of 1,200 ppb and 2,100 ppb, respectively The laboratory report noted the presence of an immiscible, lighter-than-water sheen on water samples P2-H20, P3-H20 and P4-H20, indicating the possible presence of free product in the area Analytical results of grab ground water samples are summarized in Table 2 - Analytical Resiilts of Gi ound Wafer Samples The laboratory report (MAI Lab I D No 81169 to 81172) and chain-of-custody forms are included in Appendix B The estimated dissolved TPH-g and TPH-d concentrations in the area assessed by P I through P4 is depicted in Figure Nos 4 and 5 -Appi oximate Extent of Dissolved TPH-g and Appi oxmiate Extent of Dissolved TPH-d, respectively 5.0 SUMMARY AND CONCLUSIONS Based on ground water monitoring data collected approximately 100 feet east of the site, the prevailing ground water flow direction near the site area is generally toward the south Based upon data collected on 23 September 1997, AGE concludes the following • First encountered ground water is at 21 feet bsg • Soil and ground water on the site has been impacted by petroleum hydrocarbons • Laboratory and field data suggest extensive petroleum hydrocarbon-impacted soil at the site exists near the UST area (PI through P3) and the dispenser island area (P4) at depths between 5 and 20 feet bsg Advanced GeoEmiromnental,Inc t