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' 09 July 1999 AGE-NC Project No 95-0184 Page 3 of 4 of approximately 15° from vertical and therefore was not used for calculating the ground water ' elevation and flow direction ' The inferred ground water flow direction in March 1999 was toward the east with a gradient of approximately 0 002 ft/ft (Figure 3) Measurable free product was not detected with the interface probe during the March 1999 monitoring event I 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' TPH-g was detected in each well sampled, with concentrations as high as 160,000 parts per billion (ppb, reported as micrograms per liter) Benzene was detected at concentrations as high as 44,000 ' ppb TPH-d was detected in the sample from MW-4 at a concentration of 4,700 ppb Hydrocarbon concentrations detected in samples collected from MW-4, VW-213, and VW-513 are indicative of the presence of free product ' D w - 4 12-Dichloroethane IPE as detected in the sample from MW 3 at a concentration of 2 ppb , (DCA)was detected in six of the ten wells sampled at concentrations as high as 1,900 ppb (VW-2B) Nine additional constituents were detected with EPA Method 8260 at concentrations as high as 2,000 ppb (1,2,4-trimethylbenzene, MW-4, VW-4 and VW5C) Analytical results are summarized on ' Tables 2 and 3 The laboratory report (MAI sample Nos 05829-05838) and chain-of-custody forms are included in Appendix B ' Lower hydrocarbon concentrations were detected in MW-7, located between MW-4 and the remaining wells at the site The lower hydrocarbon concentrations detested in samples collected from MW-1, MW-2 and MW-3 are probably due to the deep drowning of these wells(23 to 24 feet) ' 4.0. DISCUSSION AND CONCLUSIONS Based upon data collected from the site, AGE concludes the following ' • Petroleum hydrocarbons were detected in each well sampled, at concentrations as high as 160,000 ppb Although not measurable in the wells, free product appears to remain at the ' site Additibnal monitoring wells will be necessary to delineate the horizontal extent of hydrocarbon-impacted ground water ' • Concentration of hydrocarbons detected at the site have generally remained stable • The inferred ground water flow direction was toward the east during the March 1999 monitoring event The inferred flow direction has generally been toward the east to southeast .advanced GeoEnvironmenlal.Inc