ARCHIVED REPORTS_2010 ANNUAL REPORT

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Nestle USA, Inc., Ripon, California March 31, 2011 2010 Annual Report Between January 1, 2010 and December 28, 2010, wells EU-3 and EU-4 (Industrial Avenue) and wells E-2 and E-6 (Stockton Avenue) extracted 96.1 MG of groundwater. The City of Ripon non- potable system accepted approximately 57.4 MG of treated water from the Stockton Avenue extraction and treatment system (Table 10). The remaining 38.7 MG of treated water from the Industrial Avenue extraction and treatment system was discharged to the City of Ripon wastewater treatment lagoons via the industrial sewer. The two extraction and treatment systems removed approximately 31.6 pounds of VOCs from the Upper and the Intermediate aquifers combined. This is equivalent to 0.33 pounds or 150 grams of VOC removal per million gallons of water pumped and treated. ECM sampled and analyzed the mid-point from the extraction and treatment systems for VOCs on a monthly basis, and the influent and effluent on a quarterly basis, as required by the 2010 MRP (Table 9.1). During weekly operations and maintenance (O&M) visits to both treatment systems, ECM inspected and maintained the systems to optimize operations. The field logs for these visits can be found in Appendix E of this report. ECM operated, maintained, and monitored three private wellhead treatment systems in 2010. ECM sampled these systems twice per month in accordance with the MRP. The field logs for these visits can be found in Appendix E of this report. 4.1 INDUSTRIAL AVENUE EXTRACTION AND TREATMENT SYSTEM Nestle upgraded the Industrial Avenue extraction and treatment system in February 2008, consistent with the approved IRAP22. The upgraded extraction and treatment system used two in- line 10,000-pound GAC vessels and one 5,000-pound polishing GAC vessel to treat groundwater extracted from wells EU-3 and EU-4. After the startup of the new IRAP wells on February 14, 2008, extraction from wells EW-1 and EI-1 ceased. Extraction from wells EU-3 and EU-4 targeted Upper Aquifer locations characterized by the presence of high dissolved TCE concentrations to optimize mass removal rates and provide containment at the Site. ECM resumed extraction from well EI-1 on October 29, 2010, as a result of the M-1 OA investigation, to target mass removal and provide containment in the "lower A zone" (100 feet— 115 feet bgs) of the Upper Aquifer(Section 4.1.1). 4.1.1 OPERATION AND MAINTENANCE The Industrial Avenue system treated the extracted groundwater and discharged it to the City of Ripon WWTP via the industrial sewer. This system extracted a total of 38.7 MG of groundwater and removed 12.22 pounds of VOCs from the Upper Aquifer between January 1, 2010 and December 28, 2010. This is equivalent to 0.32 pounds of VOCs removed per every million gallons of water extracted (Table 10). Between January 1, 2010 and December 28, 2010, the Industrial Avenue extraction and treatment system was operational 99% of the time (Appendix F). Approximately 73 hours of down-time occurred when the extraction wells were shut down to conduct a recovery test for EU-3 and EU-4 capture zone analysis in May 2010 and 30 minutes of downtime occurred when the system was shut down to conduct an optimization test for EI-1 pumping. Under typical operating conditions, extraction wells EU-3 and EU-4 pumped at 29 gpm and EI-1 pumped at an average 95 gpm. On October 28, 2010, ECM's contractor, Howk Systems (Howk), redeveloped well EI-1 and placed a 10 horsepower pump in the well. ECM field technicians tested the pump, reconfigured the wiring, and balanced the flow rates from wells EI-1, EU-3, and EU-4, to maximize the pumping rate in well EI-1. On October 29, well EI-1 began running at 90 gpm concurrently with wells EU-3 20