ARCHIVED REPORTS_2010 ANNUAL REPORT

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Nestle USA, Inc., Ripon, California March 31, 2011 2010 Annual Report outside of the local area. Additionally, differences in timing and amounts of water pumped from the City of Ripon wells may affect groundwater elevations in the Study Area. ECM observed a decreasing trend in the average water levels in the Lower Aquifer since 1999 e.g. wells M-6D, M-8D, and M-20D (Table 2). Declining water levels in the Lower Aquifer are primarily due to pumping from this zone by the City of Ripon (Table 1, Table 8) to meet water demand. Since 2003, the City of Ripon has installed four new wells that target the Lower Aquifer for water production. 3.2.3 GROUNDWATER OBSERVATIONS ECM's review of the 2010 quarterly groundwater elevation data for the Study Area include observations regarding: • The groundwater flow direction; • The influence of pumping, and • The presence of a groundwater mound. Groundwater Flow Direction The groundwater flow direction within the Study Area in the Upper and Intermediate aquifers is generally northwesterly in the first three quarters of 2010 (Figure 3-1 through Figure 3-3, and Figure 4-1 through Figure 4-4) and changes in the Fourth Quarter 2010 (Figure 3-4 and Figure 4-4). Groundwater in the Lower Aquifer flowed west (Figure 5-1 through Figure 5-4) throughout 2010 and the flow directions has been consistent since 2005e. Influence of Pumping Depressed groundwater levels indicate the influence of pumping in the Upper and Intermediate aquifers (Figure 3-1 through Figure 4-4). ECM made the following observations regarding the influence of pumping in the aquifers: • Pumping in municipal wells MW-5 and MW-10 resulted in drawdown in the Upper and Intermediate aquifers in all four quarters of 2010. • Greater than half a foot of drawdown was observed in wells as far north as well M-48A and as far south as well M-46A in May 2010". This represents active pumping in wells EU-3 and EU-4 at the Industrial Avenue extraction and treatment system and verifies that the capture zone is maintained. • Depressed groundwater levels were observed at extraction well E-2 (Stockton Avenue) and monitoring well M-813 in the first three quarters of 2010. After extraction from well E- 2 ceased on October 1, 2010, groundwater elevations rebounded at M-813 between October 1 and October 11 (Appendix C, Figure 3-4). • Depressed groundwater levels due to active pumping in well E-6 (Stockton Avenue) were present in the first three quarters of 2010, prior to the shutdown of the system on October 1, 2010. Observed increases in the water level elevation in well M-8C1 since 2006 were due to declining pumping rates in well E-6. The water level is expected to stabilize because well E-6 is no longer pumping. e See Former Nestle USA, Inc. Facility Annual Reports since 2005. 12