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01 April 2004 AGE-NC Project No 97-0301 ' Page 4 of 6 twenty-four water samples Various BTEX constituents ere detected In the same water samples ' (MW-1, MW-5 and MW-7) at concentrations as high as 600 µg11 xylene in the sample collected from MW-7 Benzene was detected from all three above referenced wells at concentrations of 150 ' µg11, 820 µg11 and 3,400 µg11, respectively I MTBE was detected in one water sample collected from well MW-1 at a concentration of 10 µg/1 ' (MW-8A) 1,2-DCA was detected in three (3) ground water samples collected from wells MW-1, y MW-5 and MW-7 at concentrations of 11 µg/1 , 290 µg/1 and 660 µg/1,respectively ' DIPE was detected for the first time in the sample collected from MW-5 at a concentration of 430 µg/1 No other fuel components were detected in the ground water samples Previous and current analytical results of ground water monitoring well samples are summarized in Tables 3 and 4 The tlaboratory reports (Cal Tech Environmental Laboratories Report I D No 0311-080)and chain-of- custody forms are presented in Appendix B ' 4.0. SUMMARY AND CONCLUSIONS ' Due to a field technician over-sight, the California Tank Lines Inc wells MW-3 and MW-4 were monitored and sampled during the November 2003 monitoring event instead of the Pacific Pride- ' South E1 Dorado wells MW-3 and MW-4 AGE contacted Cal Tech Environmental Laboratories to omit the MW-3 and MW-4 results from the laboratory report ' The implications from the November 2003 ground water monitoring event are as follows • Generally, depth to ground water at the site vaned between 34 and 35%2 fee bsg, ground ' water elevations ranged between 21 68 feet(MW-8A)and 22 8 feet(MW-1210 below mean sea level � • Grouno water flow direction for the area bound by First Water Zone wells MW-1,MW-2 and MW h h MW-4was inferred to be east-northeast at an approximate gradient of 0 002 ' fl/ft or less (Figure 4) Due to the low gradient at the site, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could greatly ' modify ground water flow direction • Ground water elevation generally decreased at the site an average 0 26 feet between the t September 2003 and the November 2003 ground water monitoring events The decrease in ground water elevation is probably due to seasonal fluctuation • Generally, a steep downward vertical gradient was observed from wells MW-8,MW-9 and ' MW-12 and between the First Water Zone and the Fourth Water Zone (Figure 3) Advanced GeoEnvironmental,Inc t