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L 1 12 January 2004 AGE-NC Project No 95-0121 " Page 4 of 6 , i3 2 ' LABORATORY RESULTS OF GROUND WATER SAMPLES , TPH-g was detected in water samples collected from wells MW-1 through MW-4, MW-7, VW-1, VW22 and VW-4 at concentrations as high as' 230,000 micrograms per liter (µg/1) from VW-1 - (Figure 4) TPH-d was detected in water samples collected from wells MW-1 through MW-4,MW-7 11 and VW-I'at concentrations as high as 29,000 µg/1 from VW-1,however the laboratory reported the " sample chromatograms to be representative of gasoline i f; Benzene, toluene, ethylbenzene and xylene constituents(BTEX) were detected in the ground water ; ' sample collected from wells MW-1 through MW-4, MW-7, VW-1, VW-2 and VW-4 at concentrations at concentrations as high as 33,000 µg/l toluene from well VW-1 Benzene was `detected at concentrations as great as 11,000µg/1 from well MW-1 and 29,000µg/l from well,VW-1 " IMTBE was detected in the water sample collected from wells MW-1,MW-2,MW-3,MW-7,VW-1, VW-2 and VW-4 at concentrations as high as 880 µg/1 from well VW-1, DIPE'was detected in a ' water sample collected from well MW-1 at a concentration 4 3 µg/1 No other fuel components were detected during the laboratory analysis I • Previous and current analytical results of ground water-monitoring well samples are summarized in Tables 3 and 4 The laboratory reports(Cal Tech Environmental Laboratories Sample I D 0309-176 ' and 0309-184) and chain-of-custody forms are presented in Appendix B ' 4.0. SUMMARY AND CONCLUSIONS i m L a The implications from third quarter 2003 ground water monitoring are as follows I • Groundwater flow direction for the area bound by wells MW-1 through MW-9 was inferred to be towards the northeast at a gradient of 0 001 ft/ft or less (Figure 3) The flow direction ' i likely represents the lower sand Ievel or semi-confined aquifer at the site and may not represent the upper most water table flow direction 1 I I , I~ I _ ,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 5 , flow direction Between February 1991 and May,11998, ground water elevations;at the site significantly increased from 26 feet to 7 feet ,below mean sea level (ms]), however, ground water measurements collected between May 1998 and present have,generally fluctuated very little between 7 feet and 12 feet below msl (Table 2) P 1 , II Advanced GcoEnvtronmental,Inc t I II