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I 29 April 2004 i AGE-NC Project No 98-0511 IPage 6of7 Analytical results of ground water samples are summarized in Tables 4 and 5 The inferred lateral distribution of TPH-g,benzene and MTBE is illustrated on Figure 6 Copies of the laboratory report (CTEL Laboratory IDs 0403-087-1 through 0403-087-8) and cham-of-custody forms are provided in Appendix E 4.0. SUMMARY AND CONCLUSIONS Based upon data collected from the site during the 08 March 2004 investigation,AGE concludes the following I • TPH-g and ethylbenzene were detected in soil sample P 1-20 at concentrations of 410 mg/kg and 2 7 mg/kg, respectively Total xylenes were detected in soil samples P1-20 and P1-35 Iat concentrations of 16 6 mg/kg and 0 018 mg/kg, respectively • TPH-g, benzene, ethylbenzene and total xylenes were detected in the grab ground water I sample Pl-W at concentrations of 58,000 lig/l, 53 pg/l, 1,200 µg/1 and 11,290 µg/l, respectively, the detected concentrations of benzene, ethylbenzene and xylenes were above California's Department of Health Services'Maximum Contaminant Levels(MCL)for these 10 contaminants in drinking water No other analytes of concern were detected in grab ground water sample PI-W ' • Ground water elevations in the monitored area averaged 3 75 feet above MSL with the ground water elevation increasing approximately 2 39 feet since the previous quarter The ground water flow direction was inferred to be generally west-southwesterly,consistent with previous flow directions, with a relatively flat hydraulic gradient of 0 003 ft/ft • TPH-g and BTEX compounds were detected in ground water sample MW-1 at concentrations of 7,800 µg/1 TPH-g, 280 µg11 benzene, 77 µg/1 toluene, 430 �Lg/l tethylbenzene and 3,300µg/l total xylenes,in addition,benzene was detected in sample MW- 5 at a concentration of 8 1 µg/l The detected concentration of benzene and xylenes were above the MCLs for these contaminants in drinking water • MTBE was detected only in ground water sample MW-5 at a concentration of 65 µg/1 The detected concentration of MTBE was above the Secondary MCL (5µg/1) for MTBE in ' drinking water • Analytes of concern were not detected above laboratory reporting limits in ground water samples collected from wells MW-2 through MW-4 and MW-6 through MW-8 • Hydrocarbon-impacted soil and ground water is not defined laterally along the up-gradient, east side of the site i Advanced GeoEnvironmental,Inc I