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• GROUNDWATER GRADIENT AND FLOW DIRECTION Figures 4, 5, and 6 show the groundwater elevation gradient and flow direction determined from depth to water measurements at the four on-site monitor wells on January 31, 2003, May 22, 2003, and August 7, 2003 respectively The flow direction for all three quarters was to the northeast The groundwater elevation gradient for all three quarters remained at 0 002 feet/linear foot RESULTS OF CERTIFIED ANALYSIS OF GROUNDWATER SAMPLES The results of the certified analyses of groundwater samples collected from the four monitor wells on January 31, 2003, May 22, 2003, and August 7, 2003 are shown in Table 1 Copies of the laboratory reports are included as Appendix C of this report On January 31, 2002, TPH-G concentrations in MW1-MW3 ranged from a maximum of 4300 ug/1 at monitor well MW3 to 3100 ug/l at monitor well MW 1 Monitor well MW4, completed in a lower aquifer, showed a TPH-G concentration of 360 ug/1. Benzene concentrations in MWI-MW3 ranged from a maximum of 1800 ug/l at MW3 to 720 ug/l at MW2 Monitor well MW4 showed a benzene concentration of 13 ug/l. MTBE concentrations in MW1-MW3 ranged from a maximum of 21 ug/I at MW3 to <5 ug/1 at MW 1 and MW2 MTBE was not detected above 0 5 ug/1 in MW4 On May 22, 2003, TPH-G concentrations in MWl-MW3 ranged from a maximum of • 5100 ug/1 at monitor well MW 1 to 2000 ug/l at monitor well MW2 Monitor well MW4 showed a TPH-G concentration of 600 ug/1 Benzene concentrations in MWI-MW3 ranged from a maximum of 2000 ug/l at MW 1 to 550 ug/1 at MW2 Monitor well MW4 showed a benzene concentration of 15 ug/1 MTBE concentrations in MW 1-MW3 ranged from a maximum of 32 ug/1 at MW3 to 5 5 ug/1 at MW2 MTBE was not detected above 0 5 ug/1 in MW4 On August 7, 2003, TPH-G concentrations in MW 1-MW3 ranged from a maximum of 11,000 ug/1 at monitor well MWl to 1800 ug/1 at monitor well MW2 Monitor well MW4 showed a TPH-G concentration of 270 ug/l. Benzene concentrations in MW 1- MW3 ranged from a maximum of 4800 ug/l at MW1 to 380 ug/1 at MW2 Monitor well MW4 showed a benzene concentration of 0 9 ug/1 MTBE concentrations in MW1-MW3 ranged from a maximum of 44 ug/l at MW3 to 6 8 ug/l at MW2 MTBE was not detected above 0 5 ug/1 in MW4 Figures 7, 8, and 9 show the distribution of TPH-G, BTEX, and MTBE in groundwater and the estimated lateral limits of the TPH-G in groundwater as determined from groundwater samples collected on January 31, 2003, May 22, 2003, and August 7, 2003 respectively The lateral limits of TPH-G in groundwater to the northeast are not yet determined, however, the preluninary results from Advanced Geo-Environmental, Inc CPT testing (December 2001) to the northeast suggest that the TPH-G in groundwater plume at the first groundwater depth of 25 feet bgs most likely extends beyond the . property limits 3 Are Pumn OM I-9 2003