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Nestle USA, Inc., Ripon, California March 26, 2014 <br /> 2013 Annual Report <br /> 27.87 pounds of CDCs were removed from the Upper A-zone and 4.14 pounds of COCs were <br /> removed from the Lower A-zone. <br /> Under typical operating conditions in 2013, extraction wells EU-3 and EU-4 were pumped at <br /> rates of 29 gallons per minute (gpm) and 30 gpm, respectively. Well EI-1 pumped at an <br /> average rate of 65 gpm in First Quarter 2013. A problem that resulted in a thermal overload of <br /> the pump in well EI-1 was resolved in Second Quarter 2013 and well EI-1 was pumped at an <br /> average rate of 92 gpm for the remainder of 2013. <br /> Between December 20, 2012, and December 19, 2013, the IRAP system was operational over <br /> 99 percent of the timed. From July 23 to July 29, 2013, ECM halted the operation of the pump in <br /> well EI-1 due to a broken drop pipe that was replaced by ECM field staff. The system operation <br /> was shut down for seven hours on August 13, 2013, to perform a carbon change. <br /> 3.2 IRAP PERFORMANCE MONITORING <br /> ECM collects water quality samples from the influent to the first in-series carbon vessel, at the <br /> midpoint on the piping between the two carbon vessels, and from the effluent after the final <br /> carbon vessel. Under the current MRP, ECM collects samples at the influent and effluent <br /> locations quarterly, and at the midpoint location monthly (Table 8.1). <br /> The continued decline of TCE concentrations in wells EU-3 and EU-4 indicates that the areas of <br /> highest TCE impact, which were targeted as part of the TRAP, have undergone reductions in <br /> dissolved TCE concentrations. TCE concentrations in wells EU-3 and EU-4 in December 2013 <br /> were 98 percent lower than the concentrations observed in the wells in January 2008, as <br /> illustrated in the figure below. TCE concentrations at well EI-1 were between 29 lag/L and 38 <br /> lag/L in 2013. As shown in the figure below, mass removal rates have dropped from 2.7 pounds <br /> of TCE per MG of water removed in Second Quarter 2008 (from wells EU-3 and EU-4) to 0.29 <br /> pounds of TCE per MG of water removed during Fourth Quarter 2013 (from wells EU-3, EU-4, <br /> and EI-1). ECM will seek permission from the RWQCB to shutdown the IRAP system coincident <br /> with the initiation of the offsite remediation system. <br /> d System operational data are provided in monthly System Performance Reports per the 2010 MRP. <br /> 14 <br />