ARCHIVED REPORTS_2013 ANNUAL REPORT

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Nestle USA, Inc., Ripon, California March 26, 2014 2013 Annual Report These data are indicative of source mass removal associated with the Interim Remedial Action Plan (TRAP) extraction and treatment system (TRAP system) and groundwater extraction at EI-1. • TCE concentrations in well M-10A were relatively stable in 2013 (160 pg/L to 190 pg/L) and lower than the historical maximum of 340 pg/L in 2010. • The chloroform concentrations in well M-47A increased from 30 pg/L in First Quarter 2011 to 62 pg/L in Second Quarter 2011. Chloroform concentrations were approximately 70 pg/L in the first half or 2012 and increased to from 110 pg/L in May 2012 to 250 pg/L in January 2013. Concentrations in the Second, Third and Fourth quarters 2013 in this well were greater than 300 pg/L. Similarly, the chloroform concentration in well M-51A increased from 27 pg/L in Fourth Quarter 2011 to 79 pg/L in First Quarter 2012, then decreased throughout 2012 to 23 pg/L in Fourth Quarter 2012. The chloroform concentration remained consistent throughout 2013, and was 50 pg/L in Fourth Quarter 2013. Wells M-47A and M-51A are located approximately 35 feet and 140 feet, respectively, from well EI-1. Concentrations of chloroform in well EU-4, located between wells EI-1 and M-47A, have ranged from 20 pg/L to 30 pg/L since the well began pumping in 2008; however, the chloroform concentration increased to 51 pg/L in First Quarter 2013 and was 74 pg/L in the Fourth Quarter 2013. Chloroform was used historically at the Site and has been reported in wells M-213 and M-2A at concentrations as high as 110 pg/L and 480 pg/L, respectively. 2013 chloroform concentrations in wells M-213 (51 pg/L) and M-2A (below the RL) are below maximum reported concentrations (Appendix B). These wells are both sampled annually in the second quarter. The increased concentrations of chloroform reported in wells M-47A and M-51A appear to correlate with the restart of extraction well EI-1 in October 2010. • TCE and cis-1,2-DCE concentrations in well M-49A indicate a slightly increasing trend since monitoring began in 2008. However, TCE and cis-1,2-DCE concentrations were relatively constant during the 2013 monitoring events, with the exception of a decrease reported in First Quarter 2013 (Table 5.1) which may be due to a sampling or laboratory error. • The cis-1,2 DCE concentration in well M-14A increased from 5.2 pg/L in 2011 to 18 pg/L in 2012 and declined to 5.1 pg/L in 2013. The historical maximum cis-1,2 DCE concentration in this well was 220 pg/L in 1991. • The TCE concentration in well M-22A increased from 23 pg/L in 2008 to 64 pg/L in 2011 and decreased to 41 pg/L in 2012. During the 2013 annual sampling event, the TCE concentration increased to 80 pg/L, which is still below the historical maximum concentration of 190 pg/L in June 1992. Intermediate Aquifer • Sixty-five percent of the Intermediate Aquifer wells have had decreasing or relatively constant cis-1,2-DCE concentration trends over the last five years of monitoring. • In the vicinity of the Site, TCE and cis-1,2-DCE concentrations in wells M-25C1 and M-25C2 have increased since 2009 (Appendix C). The historical maximum TCE and cis-1,2-DCE concentrations were 99 pg/L and 66 pg/L, respectively in well M-25C1. Current TCE and 11