ARCHIVED REPORTS_SITE STATUS REPORT 2009 2ND QUARTER

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Nestle USA, Inc., Ripon, California August 11, 2009 Second Quarter 2009 Site Status Report 6 RECOMMENDATIONS Based on the information collected during this quarterly monitoring event and past quarterly events and investigations, the following recommendations are made: oo Continue assessing system performance data from the On-Site groundwater extraction and treatment system and make any necessary operational changes to ensure that the system continues to meet the containment and mass removal goals as delineated in the TRAP. Nestle is currently considering pumping only from EU-4 to evaluate capture and mass removal in the IRAP area and has submitted a request to the RWQCB to initiate the operational changes for that purpose'. oo Nestle will continue to evaluate the COC data for well M-113 as additional data are collected to determine the relationship between the variation in the COC concentrations and water level elevation changes. oo A work plan (Monitoring Well Installation Work Plan for Industrial and Stockton Avenue Extraction and Treatment Systems, ECM, 2009) for the installation of additional wells at the On-Site and Off-site extraction and treatment system locations has been submitted to the RWQCB to assist the evaluation of proposed Remedial Alternatives$ which will be conducted in the Remedial Action Plan/Record of Decision (RAP/ROD). oo Extraction from the Upper Aquifer (B-zone) at the Off-Site extraction and treatment system should be discontinued, since the mass removal is minimal and the area of impact is limited. oo Future pumping from well E-6 should be evaluated against the management of the pumping schedules of production wells around it. Off-site wells proposed in the work plan discussed above will also be used to assess the decreased efficiency of extraction well E-6, despite rehabilitation efforts. oo Discontinue treatment of water from the replacement well installed at 7501 Kiernan Avenue. This recommendation is based on the analysis of the data that indicates that no significant health risk is associated with the groundwater produced by this well because (a) the concentration of TCE and cis-1,2-DCE are well below respective state and Federal MCLs and below the California PHG, and (b) Nestle supplies the household with bottled water for drinking. ' ECM, 2009b. Industrial Avenue (TRAP) Groundwater Extraction System—Proposed Changes in Remediation System Operation, June 11, 2009. 8 ECM, 2009a. Revised Feasibility Study, Former Nestle USA, Inc. Facility, Ripon, CA. January 30, 2009. 12