ARCHIVED REPORTS_2010 ANNUAL REPORT

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APPENDIX A - SITE BACKGROUND INFORMATION A1.1 FACILITY HISTORY This former Nestle facility was located at 230 Industrial Avenue in Ripon (Site), California, seven miles north of the City of Modesto and along California Route 99 (Ref: Figure 1 of 2010 Annual Report). Originally built in the 1930s for dairy production, the facility began manufacturing soluble instant coffee in 1948. Manufacturing operations ceased in 1994, and the main buildings were demolished in 1995. A third party purchased significant portions of the property in 2005. Following the sale, Nestle retained ownership of properties at two locations: one at the northeast corner of the former manufacturing facility, and the other at 519 South Stockton Avenue. Both properties exist within industrial zones in the southeast portion of the City of Ripon. Other industrial properties lie to the west and south of the Site. According to the City master plan, the area will remain zoned as industrial at least until the year 20401 . A1.2 SITE BACKGROUND From the 1950s until 1970, the facility operated a closed-loop extraction process to decaffeinate coffee. This process used trichloroethene (TCE) as a solvent to extract caffeine from green coffee beans. Aboveground tanks stored the TCE immediately south of the decaffeination building. The decaffeination process included gravity separation and distillation of the solvent in a closed-loop system with TCE returning to a solution tank for reuse. The effluent from the separator discharged into a sewer line between the decaffeination building and the warehouse. This sewer line drained to the City-owned and operated sewer main along Industrial Avenue, which transported waste from many industrial facilities in Ripon. The City of Ripon industrial wastewater was discharged into the percolation/evaporation ponds. The details of the City's Waste Water Treatment Plant (WWTP) operation can be found in City of Ripon Effluent Disposal Percolation Study Report2. In 1970, methylene chloride replaced TCE in the decaffeination process until 1986, when a water extraction process replaced the methylene chloride process. A1.3 DISCOVERY OF INITIAL RELEASE Four Nestle facility production wells (N-1, N-2, N-3 and N-4) supplied water for the manufacturing processes. In January 1986, routine sampling and analysis of N-1 and N-2 revealed TCE in the groundwater. In May 1986, TCE and associated solvent byproducts ("constituents of concern" or"CDCs") were detected in nearby municipal wells MW-1 and MW-6. Subsequent to these findings, groundwater extraction from well MW-1 was terminated. MW-1 was decommissioned sometime between 19943 and 1998. MW-6 ceased operation in 1989 and was decommissioned in July 2009. A granular activated carbon (GAC) system commenced treatment operations at well N-1 in July 1986. Nestle destroyed the Industrial Avenue production wells in 1995. A1.4 REGULATORY OVERSIGHT The Regional Water Quality Control Board — Central Valley Region (RWQCB) is the agency with primary jurisdiction over this project. In response to the detection of TCE in N-1, N-2, and the City of Ripon wells (MW-1 and MW-6) in 1986, the RWQCB required Nestle to develop a groundwater monitoring program for the facility and to investigate soil and groundwater Appendix A Page Al of A7