ARCHIVED REPORTS_2010 ANNUAL REPORT

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Nestle USA, Inc., Ripon, California March 31, 2011 2010 Annual Report Groundwater Mound A groundwater mound exists in the Upper and Intermediate aquifers near the municipal WWTP and the northwest corner of the former Neenah Paper Company industrial wastewater ponds. Groundwater flows outward from the mound in all directions in this area. Historical water elevation data suggested the presence of this mound as early as 200412. • The groundwater mound is likely caused by recharged water and wastewater management practices of the City of Ripon and the former Neenah Paper Company. The City of Ripon recharges the Upper Aquifer with water pumped from the South San Joaquin Irrigation District (SSJID) and some water from Stockton Avenue extraction and treatment system into a recharge pond on Doak Boulevard, north of the City of Ripon WWTP lagoons. Historically, the former Neenah Paper Company used effluent from pond ASB-2 to irrigate 86 acres of trees surrounding the northern half of the facility and percolation fields to the south near the Stanislaus River (Figure 3-1 to Figure 3-4). • The location of the center of the groundwater mound varies with: o The timing and volume of water used during irrigation activities at the former Neenah Paper Company facility, o The volume of discharge to the City of Ripon WWTP, and o The volume of recharge to the City of Ripon's recharge pond. • The locations of the centers of the mounds in both the Intermediate Aquifer and Upper Aquifer coincide in each quarter of 2010 (see Figure 3-1 through Figure 4-4). 3.3 WATER QUALITY ECM sampled wells in the monitoring program using one of three methods: • Passive Diffusion Bag (PDB), • Purge, or • Grab. Sampling methods and summaries for the first three quarters of 2010 are provided in the quarterly Site Status reports. The Fourth Quarter 2010 is discussed below. ECM sampled a total of 64 wells using the passive diffusion bag (PDB) sampling method during the semi-annual event in the Fourth Quarter 2010. ECM deployed PDBs in all but four monitoring wells (M-5C1, M-28C, M-28C1, and M-27D) in the Fourth Quarter 2010. The purge method generated water that was then treated by the groundwater treatment systems. ECM collected grab samples from production wells, domestic wells, and the groundwater treatment systems. TestAmerica Laboratories, Inc. (TestAmerica), a California-certified laboratory in Pleasanton, California, analyzed all samples for halogenated VOCs using EPA Method 82608. Kiff Analytical, subcontractor to TestAmerica, analyzed samples from municipal drinking water supply wells and domestic water supply wells using EPA Method 524.2 for drinking water. The laboratory reports for the Fourth Quarter 2010 are included in Appendix D. Laboratory reports for the first three quarters of 2010 were included in the quarterly Site Status Reports. 3.3.1 UPPER AQUIFER An evaluation of COC impacts in the Upper Aquifer is provided in the following sections. 13