ARCHIVED REPORTS_2010 ANNUAL REPORT

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Nestle USA, Inc., Ripon, California March 31, 2011 2010 Annual Report 12. Concentrations of cis-1,2-DCE and VC (which are TCE breakdown products) in the Intermediate Aquifer generally exceed those in the Upper Aquifer. This relationship is most pronounced near the lagoons, suggesting that the high organic compound content in sewage may enhance degradation of TCE through reductive dechlorination. 13. Groundwater extraction wells help contain migration of the CDCs as evidenced by drawdown observed near these wells. Similar containment by City of Ripon production wells could be accomplished, if they are operated continuously. 14. Based on the results of assessment of Second and Third Quarter 2010 groundwater data, intrinsic remediation appears to be occurring in the Upper and Intermediate aquifers. 6 RECOMMENDATIONS • ECM recommends a maximum 60-day shutdown of extraction well EU-3 to evaluate the rapid decline in TCE mass removal rates at the Industrial Avenue extraction and treatment system for system optimization. • ECM recommends continued monitoring of COC concentrations at M-10A to evaluate the influence of resumed extraction at well EI-1. • ECM recommends finalizing the Water Management Plan for the Ripon Study Area, including implementation of a process for coordinating with the City of Ripon regarding the construction of any future production wells to prevent vertical, preferential flow paths. • ECM recommends continued monitoring of wells M-20D, and other wells located downgradient of former conduit wells TH-8 and TH-10, to evaluate the effects of the 2009 modifications. • ECM recommends the evaluation of future monitoring data from the private supply wells at 7501 Kiernan Avenue and other nearby wells, to confirm that the decommissioning of a former private irrigation well removed the suspected conduit between aquifers. • ECM recommends continued monitoring of well M-61D and M-40D to evaluate the effect of closure of City of Ripon production wells MW-4 and MW-6. • ECM recommends intrinsic remediation as an overall Remedial Action for groundwater beneath the Study Area. 7 PLANNED ACTIVITIES FOR 2011 Future reporting and field activities based on on-going Site activities and recommendations from Section 6 appear below. 7.1 REPORTING ACTIVITIES FOR 2011 The following reports reporting activities are proposed for 2011: 1. Submit quarterly status reports, monthly sampling results for private wells, and monthly system performance reports for the Nestle and private well treatment systems to the RWQCB; 2. Submit sampling results to the private well owners based on sampling frequency; 28