ARCHIVED REPORTS_2010 ANNUAL REPORT

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Nestle USA, Inc., Ripon, California March 31, 2011 2010 Annual Report In June 2009, Nestle submitted a proposa125 to the RWQCB to modify the pumping at EU-3 for a 60 day period following observed reduction in the extraction and treatment system mass removal rates. The purpose of the pumping modification was: • To assess the possibility of extracting additional mass within the stagnation zone, and • To evaluate future changes to the operation to optimize mass removal. ECM installed additional wells (M-50A and M-51A) in December 2009, in response to the RWQCB's request to verify the current extent of capture provided by the EU-3 and EU-4 wells. In May 2010, ECM shut down the Industrial Avenue extraction and treatment system for 72 hours to collect groundwater elevation data for the new and old monitoring wells and to estimate the hydraulic capture zone for extraction wells EU-3 and EU-4. ECM's capture analysis indicated that the actual capture zone is slightly larger in size than the capture zone predicted by the groundwater flow model, suggesting that the numeric groundwater flow model represents a conservative estimate of the hydraulic capture actually provided by wells EU-3 and EU-4 under in-field pumping condition S26. Field parameters including TDS, temperature, conductivity, and pH in the Industrial Avenue extraction and treatment system effluent are measured twice per month in accordance with MRP requirements (Appendix E). Metals concentrations in the influent samples were found in ranges similar to historical metals concentrations in groundwater (see Table 9.1). The TDS concentration for the system effluent in 2010 increased from 790 mg/L on January 7, 2010 to 1050 mg/L on December 28, 2010. The average TDS concentration in 2010 was 964 mg/L as compared to 943 mg/L in 2009. No COCs were detected in any of the effluent samples collected from the Industrial Avenue extraction and treatment system during the 2010 sampling events. The treatment system was 100% efficient in removing COCs from the extracted groundwater. No modification to the treatment system is warranted at this time. Nestle will continue to evaluate the groundwater extraction and treatment system in 2011 and adjust the system operation to maintain efficient and effective mass removal and hydraulic containment. 4.2 STOCKTON AVENUE EXTRACTION AND TREATMENT SYSTEM The Stockton Avenue groundwater extraction and treatment system was equipped with an air stripper to remove VOCs from the extracted water prior to discharge to the City of Ripon non- potable water system. VOCs in the off-gas from the air stripper are destroyed with a catalytic oxidizer prior to discharging the off-gas to the atmosphere. The system ceased operation in October 2010 as discussed below. 4.2.1 OPERATION AND MAINTENANCE The Stockton Avenue system extracted and treated a total of 57.4 MG of groundwater through the Third Quarter 2010, prior to shutdown in October, removing approximately 19.42 pounds of VOCs. This is equivalent to 0.34 pounds of VOCs removed per million gallons of water extracted (Table 10). The system discharged the treated groundwater to the City of Ripon non- potable water system during the first three quarters of 2010. The E-2 extraction well pumped at an average rate of 71 gpm, removing approximately 27.91 MG of groundwater from the Upper Aquifer in 2010. The E-6 extraction well pumped at an average of 76 gpm, removing approximately 29.88 MG of groundwater from the Intermediate Aquifer. Between January 1, 2010 and October 1, 2010, the system downtime was approximately 270.85 hours for maintenance, repairs, and system initiated shut-downs designed to protect the 22