ARCHIVED REPORTS_2013 ANNUAL REPORT

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Nestl6 USA, Inc., Ripon, California March 26, 2014 2013 Annual Report IRAP System Extraction Well TCE Concentrations and TCE Removal Rate 350 3.0 0 E 300 2.5 L d 250 J 2.0 0 a� 0 200 2 0 1.5 °' r a 2 150 c — EI-1 1.0 0 100 Start-up o W 4) U 0.5 50 w m 0 0.0 w Mar-08 Aug-08 Mar-09 Aug-09 Mar-10 Aug-10 Mar-11 Aug-11 Mar-12 Aug-12 Mar-13 Aug-13 U H t EU-3 --w-EU-4 EI-1 TCE Removal Rate Field parameters including total dissolved solids (TDS), temperature, conductivity, and pH in the IRAP system effluent are measured twice per month in accordance with MRP requirements (Table 8.1, Appendix E). The TDS concentration for the system effluent in 2013 ranged from 490 milligrams per liter (mg/L) to 1,010 mg/L. Chloroform (4.0 pg/L) was detected in the effluent sample collected from the IRAP system on July 9, 2013. The GAC was changed in the treatment system on August 13, 2013. The carbon had previously been changed in the treatment system on May 18, 2012. According to Siemens, the carbon supplier, the presence of chloroform may cause higher carbon usage resulting in more frequent carbon replacements. TCE was reported at a concentration of 0.53 pg/L in the sample collected immediately following the carbon change; however, the confirmation sample collected on August 16, 2013 was below the RL. The treatment system was over 99 percent efficient in removing COCs from the extracted groundwater and met MRP requirements. Groundwater drawdown (Table 4) measured at wells in the area of IRAP extraction wells (EU-3, EU-4, and EI-1) in 2013 continue to confirm hydraulic capture zones are consistent with groundwater modeling predictions". 3.3 REMEDIAL ACTION PLAN The RAP will present the details of technology process options for the remedial alternative presented in the 2011 Revised FS contingent upon revisions presented in a FS Addendum in agreement with the action plan developed with the RWQCB in December 2013 (see Section 15