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v o A S S O C I A T E S I N C ATC collected one groundwater sample from the Domestic Well at 10 minutes after the pump test was started A second groundwater sample was collected 4 hours and 55 minutes after the ' start of pumping The groundwater samples were placed on ice and will be analyzed for TPHg utilizing EPA method 8015 modified, BTEX utilizing EPA method 8021B, and MTBE, ETBE, DIPE, TAME, TBA, 1,2-DCA, and EDB utilizing EPA method 8260B Groundwater was extracted from the Domestic Well at a constant rate estimated at approximately 10 gpm for 5 hours and discharged to a 5,000-gallon polyethylene storage tank temporarily stored on-site ' Water level data obtained during the pumping test from the upper water bearing zone was observed during the course of the test A decrease in the water level of the upper water-bearing zone (0 018 feet in well MW3, 0 044 feet in well AS 1, and 0 034 feet in piezometer AS 1 d) was interpreted as confirmation of a hydraulic connection between first and second water bearing zones and the pump test was terminated Figures 9 and 10 depict the water levels in key observation well during the pump test and the recovery after the pump test The pump, discharge hose, and transducers were removed from the Domestic Well and the observation wells upon termination of the pumping test 4_2 Groundwater Pump Test Data ' The groundwater pumping rate during the pump test, as measured by a flow meter, averaged approximately 9 4 gpm, which over a 5 hour period yields approximately 2,825 gallons of groundwater extracted from the domestic well i OV m 4.3 Groundwater Sampling and Analysis -�- j 10 ' Groundwater samples were collected from the domestic well 15 minutes after the beginning of the pump test and at the completion of the pump test Groundwater samples were transferred ' into appropriate sample containers via clean sampling ports installed in the groundwater extraction system piping Sample containers were then labeled with sample identification, placed on ice, and shipped under chain-of-custody to Argon Laboratories, a California state-certified ' analytical laboratory for chemical analysis of TPHg by EPA method 8015M, BTEX by EPA method 8021B, and MTBE, TAME, ETBE, DIPE, TBA, 1,2-DCA, and EDB by EPA method 8260B Groundwater analytical results are summarized in Table 2, and laboratory data sheets are ' presented in Appendix B 44 Results of Groundwater Pump Test ' The domestic well was pumped at an average rate of 9 4 gallons per minute for approximately 5 hours Based on the calculated average flow rate and the pump test duration, approximately 2,825 gallons of groundwater were extracted from the domestic well The maximum observed drawdown at the domestic well was 1 91 feet Drawdown of up to 0 04 feet was measured in the 8 lEnviromental116393aEPORTSlcptpumpreport doe 6 /