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 1 INTRODUCTION On behalf of Nestle USA, Inc. (Nestle), Environmental Cost Management, Inc. (ECM) prepared this Second Quarter (April - June) 2009 Site Status Report to present the results of groundwater monitoring and remedial activities associated with the former Nestle facility located at 230 Industrial Avenue (Site) in Ripon, California (Figure 1). For the purpose of this report, the term "Site" refers to the property located at 230 Industrial Avenue, in Ripon, California once owned by Nestle. The term "Study Area" refers to a wider area of investigation in the larger Ripon vicinity (Figure 1). ECM conducted monitoring and sampling activities in accordance with the following directives: oo Cleanup and Abatement Order No. R5-2006-0720 93-712 (CAO) issued on July 24, 2006 by the California Regional Water Quality Control Board-Central Valley Region (RWQCB); and oo Monitoring and Reporting Program (MRP) No. R5-2005-0829 issued on July 21, 2005. Nestle requested changes to the MRP in a letter to the RWQCB dated May 7, 2007. The groundwater monitoring in this quarter included monitoring and/or sampling of a total of 166 wells in the Study Area (Figure 2). Nestle continues to operate, maintain, and monitor groundwater extraction and treatment systems at 230 Industrial Avenue and at Stockton Avenue in Ripon. Nestle also operates, maintains, and monitors well head treatment systems at two private wells located south of the Stanislaus River. 2 SITE HYDROGEOLOGY The Study Area is underlain by fluvial deposits associated with the Stanislaus River and alluvial fan deposits. Detailed information regarding the physiographic setting and geology of the region is presented in the Updated Site Conceptual Model (SCM) prepared by AMEC-Geomatrix'. Groundwater is first encountered at a depth of 20 to 40 feet below ground surface (bgs) beneath Ripon. Groundwater generally flows in the direction of the regional groundwater gradient, but is locally affected by recharge and discharge areas and fluctuates with precipitation cycles and the stage of the Stanislaus River. Influence from recharge areas such as the Stanislaus River, the City municipal lagoons, and irrigation fields currently located on the property owned by Neenah Paper Company causes groundwater to move away from these areas. Pumping wells located north and south of the Stanislaus River direct local groundwater flow toward the center of pumping. The alluvial aquifer system underlying the Study Area consists of three high-producing water-bearing zones designated as the Upper Aquifer, the Intermediate Aquifer, and the Lower Aquifer. Each of these zones typically contains more than one water-bearing unit with similar water level elevations and water chemistry. Aquitards consisting of fine- grained silts and clays generally separate water-bearing units. A regionally extensive clay aquitard, called the Corcoran Clay, separates the Intermediate Aquifer from the confined Lower Aquifer zone below it. This clay layer is thickest to the south of the AMEC Geomatrix, January 30, 2009. Site Conceptual Model-January 2009 Update, Former Nestle Facility and Surrounding Area, Ripon. 1