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AMBRIA 62,000 ppb, 37,000 ppb, and 34,000 ppb, respectively The final groundwater samples collected from MW-4 on September 12 contained 31,000 ppb MTBE and 36,000 ppb TBA Certified analytical reports are provided in Appendix A September 2003 Drawdown Analyses. Water level fluctuations in wells MW-3 and MW-7 and piezometers P-1 and P-2 were small and correlated with each other The fluctuations in these wells and piezometers also correlated with barometric pressure fluctuations, which is common for unconfined aquifers A graph of barometric pressure reading versus time is presented in Appendix B Cambria observed a maximum drawdown of 0 23 feet in piezometer P-1, which is located approximately 12 feet from the pumping well MW-4 The water level in the pumping well MW-4 was drawn down approximately 6 5 feet, to near its total depth Based on this data, it does not appear that pumping from well MW-4 affected water levels at the observation points Instead, the data suggest that water level changes observed durmg_pumpng are_mostly attributed to changes_ip barometric pressure The lack of significant effect on groundwater levels in wells --,and piezometers near MW-4 from pumping in that well is a good indication that it would be very difficult to establish hydraulic control of groundwater beneath this site Of special interest is a discrete water level drawdown and subsequent recovery from the 3,000-to 4,000-minute interval This discrete fluctuation was observed at all the observation points, but does not correspond with a change in barometric pressure, and pump operation was consistent during this time interval Therefore, it does not appear—to be-an_effect_a umpmg from well MW-4 This fluctuation may have been i natural background fluctuation o mechanically induced by another source ` ;^f• � Because drawdown in the observation points was minimal, Cambria was limited to analyzing the recovery data from pumping well MW-4 Cambria analyzed the recovery data using AquiferTest for Wmdows® version 3 01 software from Waterloo Hydrogeologic, Inc Appendix B presents the pump test analysis reports Recovery data from the constant rate test were analyzed by the Theis Recovery method to estimate hydraulic conductivity and transmissivity Cambria estimated the hydraulic conductivity of this unconfined aquifer tobe 5 3�meters/day and the transmissivity to be 16 6 square meters per day The hydraulic conductivity yielded from the recovery data analysis is consistent with fine-grained sand (Todd, 1980) which correlates well with the soil types logged for this well (sand, silty sand, and sandy silt) These results are also consistent with the results of the 2002 aquifer pump test October 2003 GWE Event. Cambria conducted the second batch GWE event on well MW-4 from October 27 through 31, 2003 The GWE equipment and procedures for this event were the 0955 6