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GeoHydrologic Consultants, Inc prior to starting the test A maximum drawdown was observed all the way down to the pump intake at 58 40 feet deep approximately one hour into the test and remained at that level for the remaining six hours of the test At one to two hours into the 8-hour test, drawdown was measured in extraction well EW-5S and the water had been drawn down ' to the pump intake and was not recharging quick enough to produce water at the surface At 1 25 hours into the test, dilution air was added to the system (manifold valve opened 100%) and the control panel was increased to 200 hertz which again produced water from ' the pump discharge at a sustained flow rate of between 0 5 and 0 25 gallons per minute A total of 180 gallons was extracted during the 8-hour test at an average flow rate of 0 375 gallons per minute Measurable drawdown was observed in observation wells MW- ' 5 (maximum drawdown 0 04 feet), TB-9 (maximum drawdown 0 26 feet), TB-11 (maximum drawdown 0 82 feet), TB-10 (maximum drawdown 0 04 feet), MW-4 (maximum drawdown 0 03), and TB-7 (maximum drawdown 0 06 feet) ' Vapor samples were collected during the multi-phase extraction test (032405ST, 032405M, and 03240505FN) from the total undiluted inlet along with groundwater samples from the pump discharge (032405ST and 032405END) Vapor samples were analyzed by Associated Laboratories of Orange, California for TPHg, BTEX, and MTBE using EPA Methods 8015 Modified and TO-15, along with oxygenates (DIPE, ETBE, ' TAME, and TBA) and fixed gases (oxygen, carbon dioxide, and methane) Groundwater samples were analyzed for TPHg, BTEX, and MTBE using EPA Methods 8015 Modified and 8260B including other oxygenates (DIPE, ETBE, TAME, and TBA) The laboratory ' analytical results are summarized in Table 6 (vapor) and Table 7 (groundwater) A total of three vapor samples (six tedlar bags) were taken for laboratory analysis from Y well EW-5S on March 24, 2005 The concentrations of TPHg were detected at 434 ppmV from sample EW-5S-032405ST, 2,880 ppmV from sample EW-5S-032405M, and 3,590 ppmV from sample EW-5S-032405FN The concentrations of benzene were detected at 1 26 ppmV from sample EW-5S-032405ST, 18 7 ppmV from sample EW-5D-032405M, and 29 1 ppmV from sample EW-5S-032405FN The concentrations of MTBE were detected at 0 334 ppmV from the sample EW-5S-032405ST, 0 845 ppmV from the sample EW-5S-032405M, and 2 14 from the sample EW-5S-032405FN The three samples were analyzed for the fixed gases oxygen, carbon dioxide, and methane Sample EW-5S-032405ST was found to have 10 48% oxygen, sample EW-5S-032405M was ' found to have 12 11%oxygen, and sample EW-5S-032405FN had a detection of 12 95% oxygen Methane for the three tested samples was below the method detection limits (0 2%) Carbon dioxide was detected in samples EW-5S-032405ST, EW-5S-032405M, ' and EW-5S-032405FN at concentrations of 11 44%, 14 66%, and 13 40%, respectively The results are summarized in Table 6 The vapor concentrations appeared to increase significantly in the total influent from the start of the combined test performed on EW-5S ' (434 ppmV TPHg) throughout the entire duration of the combined test (2,880 ppmV TPHg (M), and 3,590 ppmV TPHg(FN)) EW-5S inlet concentrations as measured in the field with a calibrated PID fluctuated throughout the duration of the test, however the ' final concentration (320 ppm) was greater than the initial concentration (260 ppm) taken at the start of the test • f ITOC 171 rdat study Page 13