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GROUNDWATER GRADIENT AND FLOW DIRECTION Figures 4, 5, and 6 shows the groundwater elevation gradient and flow direction determined from depth to water measurements at the four on-site monitor wells on May 22, 2002, August 12, 2002, and November 21, 2002 respectively The flow direction for all three quarters was to the northeast The groundwater elevation gradient for all three quarters remained at 0 001 feet/lmear foot. RESULTS OF CERTIFIED ANALYSIS OF GROUNDWATER SAMPLES The results of the certified analyses of groundwater samples collected from the four monitor wells on May 22, 2002, August 12, 2002, and November 21, 2002 are shown in Table 1 Copies of the laboratory reports are included as Appendix C of this report On May 22, 2002, TPH-G concentrations in MWI-MW3 ranged from a maximum of 8100 ug/1 at monitor well MWI to 1400 ug/l at monitor well MW2 Monitor well MW4, completed in a lower aquifer, showed a TPH-G concentration of 260 ug/l Benzene concentrations in MW 1-MW3 ranged from a maximum of 2900 ug/l at MW 1 to 310 ug/l at MW2 Monitor well MW4 showed a benzene concentration of 18 ug/l. MTBE concentrations in MW 1-MW3 ranged from a maximum of 28 ug/l at MW3 to 2 6 ug/1 at MW2 MTBE was not detected above 0 5 ug/1 in MW4 On August 12, 2002, TPH-G concentrations in MW1-MW3 ranged from a maximum of 13,000 ug/1 at monitor well MW 1 to 2,700 ug/1 at monitor well MW2 Monitor well MW4 showed a TPH-G concentration of 250 ug/1 Benzene concentrations in MWI- MW3 ranged from a maximum of 4600 ug/l at MWI to 320 ug/l at MW2 Monitor well MW4 showed a benzene concentration of 16 ug/1 MTBE concentrations in MWI-MW3 ranged from a maximum of 74 ug/1 at MW3 to 9 8 ug/1 at MW2 MTBE was not detected above 0 5 ug/l in MW4 On November 21, 2002, TPH-G concentrations in MW 1-MW3 ranged from a maximum of 11,000 ug/1 at monitor well MWI to 2,500 ug/l at monitor well MW2 Monitor well MW4 showed a TPH-G concentration of 250 ug/l Benzene concentrations in MWI- MW3 ranged from a maximum of 3600 ug/1 at MWI to 500 ug/l at MW2 Monitor well MW4 showed a benzene concentration of 13 ug/1 MTBE concentrations in MWI-MW3 ranged from a maximum of 42 ug/1 at MW3 to 6 6 ug/l at MW2 MTBE was not detected above 0 5 ug/1 m 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 May 22, 2002, August 12, 2002, and November 21, 2002 respectively The lateral limits of TPH-G in groundwater to the northeast are not yet determined; however, the preliminary 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 Piimn OM 4-12. 2002