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DISPOSITION OF WASTEWATER The 70 gallons of wastewater that were generated from purging of the monitor wells and decontamination of the purging and sampling equipment were transported via a non hazardous waste manifest to Instrat, Inc , a licensed recycling facility on October 15, 2004 GROUNDWATER GRADIENT AND FLOW DIRECTION Figure 4 shows the groundwater elevation gradient and flow direction determined from depth to water measurements at the four on-site monitor wells on September 29, 2004 The groundwater elevation has decreased by an average of 1 38 feet since the previous quarterly monitoring round on June 17, 2004 The flow direction is to the east The overall gradient is 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 September 29, 2004 are shown in Table I Copies of the laboratory reports are included as Appendix C of this report TPH-G concentrations in MW1-MW3 ranged from a maximum of 10,000 ug/l at monitor well MWI to 1500 ug/1 at monitor well MW2 Monitor well MW4, completed in a lower aquifer, showed a TPH-G concentration of 200 ug/ Benzene concentrations in MWI-NfW3 ranged from a maximum of 3300 ug/l at MWl to 310 ug/l at MW2 Monitor well MW4 showed a Benzene concentration of c0 5 ug/I MTBE concentrations in MWI-MW3 ranged from a maximum of 34 ug/l at MW3 to b 2 ug/l at MW2 MTBE was not detected above 0 5 ug/1 in MW4 TBA concentrations in 1VIW I-MW3 ranged from a maximum of 21 ug/L in MW3 to less than the laboratory detection limit of 50 ug/L in MWI TBA was not detected above the laboratory limit of 0 5 ug/L in MW4 The remaining fuel oxygenants, ETBE, DIPS, and TAME were not found above the laboratory detection limits in any of the four monitor wells The lead scavenger 1,2 Dichloroethane (DCA) was detected in a concentration of 4 9 ug/L in MW2 and MW3 DCA was not detected above the laboratory limit of 10 ug/L and 0 5 ug/L in MWI and MW4 respectively 1,2 Dibromoethane (DBA or EDB) was not found in any of the monitor wells above the laboratory detection limit that ranged from 0 5 to 10 uc, Figure 5 shows 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 September 29, 2004 3 Arc Pump QM 7-9, 2004