Laserfiche WebLink
i <br /> HydroGeo Consultants <br /> groundwater samples were collected from the discharge hose into laboratory supplied ' <br /> bottles and placed on ice for delivery to the laboratory for analysis The groundwater <br /> samples were delivered the next day to Associated Labs of Orange, California, which is <br /> certified by the State of California for the test methods performed, under strict chain of <br /> custody The samples were analyzed for TPH-g using EPA Method 8015 modified and <br /> BTEX, MTBE, and other oxygenates using EPA Method 8260B Analytical results are ' <br /> summarized in Table 7 A copy of the laboratory report and chain-of-custody <br /> documentation is included in Appendix B <br /> 5.0 PUMPING TEST RESULTS , <br /> 5.1 Analytical Methods <br /> The drawdown and recovery of the pumping well and drawdown in the observation wells , <br /> were analyzed using the Jacob Method(Cooper and Jacob, 1946) Drawdown data were <br /> plotted on semi-log axis with time (minutes) versus corrective drawdown (feet) for the , <br /> pumping well MW-5 (Figure 5) and using drawdown values measured in observation <br /> wells MW-4 (Figure 7), TBA (Figure 8), and TB-7 (Figure 9) Recovery data were <br /> plotted as total time (Tt) divided by time since recovery(To) versus residual drawdown ' <br /> (feet) as illustrated for MW-5 (Figure 6) Transmissivity, storativity, and hydraulic <br /> conductivity were then calculated using the following formulas <br /> T = 35Q/ds <br /> K= T/b , <br /> S = Tto/640i' <br /> Where ' <br /> T = transmzssivity (ft2/day) ' <br /> K = hydraulic conductivity (ft/day) <br /> S = storativzty (dimensionless) <br /> Q = pumping rate (gpm) ' <br /> ds = change in drawdown during one log cycle (ft) <br /> b = thickness of aquifer(ft) <br /> to = intercept of line with x-axis (minutes) , <br /> r = distance of observation well from pumping well (ft) <br /> 1 <br /> 1 <br /> Page 6 TQC 0171 Aquifer Test and RAP Rpt ' <br />