ARCHIVED REPORTS_SECOND QUARTER 2016 GROUDWATER MONITORING REPORT

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Diamond Pet Food&Ripon Energy July 12,2016 Second-Quarter 2016 Groundwater-Monitoring Report Page 3 of S water. This level of discharge is rare, however, occurring for one day at a time very occasionally. According to DP personnel, the maximum discharge reflects operation of all four production lines which rarely occurs. The existing wastewater facilities (Sump, Clarifier, ASB-1, ASB -2, and irrigation piping) are used to treat the wastewater through aeration and disperse it. Effluent from the Clarifier is discharged into the two aeration stabilization basins in sequence (ASB-I then ASB-2). The first pond, ASB-1, is approximately 14-feet deep and is lined; the second, ASB-2, is unlined and approximately 5-feet deep. Effluent from ASB-2 is pumped to 86 acres of fields and orchards around the site. Other ponds on the site (labeled Ponds I through 4) are unlined and are used only to contain excess wastewater in case of a system upset or a 100-year-or-greater storm event. RIPON ENERGY PLANT The Ripon Energy plant routes blowdown through the DP facilities wastewater system. The average daily flows from Ripon Energy in 2013 were between 11,136 and 166,790 gallons per day and the total volume of water discharged in 2013 was 42,237,830 gallons. The most recent (October 2012) TDS value for the Ripon Energy flow was 828 mg/L; previously(2010), TDS in the Ripon Energy flow ranged between 500 and 1,200 mg/L. Historically, the Ripon Energy flow was blended with lower TDS paper-mill effluent before being discharged, in sequence, into the two aeration basins (ASB-I and ASB-2) before being pumped to irrigation and percolation fields around the site for disposal. After the paper mill closed(May 2009), the Ripon Energy discharge was blended with water pumped from production well PW-6 before being dispersed to the irrigation fields. CITY OF RIPON The City of Ripon operates a municipal WWTF adjacent to the southwest quadrant of the DP/Ripon Energy site. The WWTF treats an average of 1.0 million gallons per day(MGD). The system consists of a series of clay-lined ponds with a surface mechanical aeration system to oxygenate the waste water. Treated effluent water is disposed by percolation from 45 acres of disposal ponds. The City is currently under directive from the CVRWQCB to evaluate the impacts of effluent disposal on groundwater quality. NESTLtS Nestles USA formerly operated an instant coffee and tea processing plant, located approximately 2,000 feet north of the DP/Ripon Energy site, from 1948 through 1986. Solvents used in the decaffeination process, and their daughter products (trichloroethene, dichloroethene, and vinyl chloride)have impacted soils at the site and groundwater in the upper and intermediate aquifers along the northern and western portions of the DP/Ripon Energy site, and have impacted wells south of the Stanislaus River. Nestl6s' consultant, Environmental Cost Management, historically operated two groundwater-treatment systems in the area to remediate the contaminant plumes, one on South Stockton Avenue and one on Industrial Avenue. The Stockton Avenue treatment systems effectively reduced the mass of contaminants in groundwater to the point where ECM was able to take the Stockton Avenue system offline on October 1, 2010. The Industrial Avenue system still is in operation. Based on the distance of the system's extraction well from the DP/Ripon Energy site and the volume of water treated by the system (<500 gpm), and the relatively high permeability of the aquifer, it is unlikely that the extraction system influences the hydraulic gradient in DP/Ripon Energy wells. 010107.08 Task 2 Lawrence&Associates W.-I CLIENTSIDiamond Pet Foods 1010107.01-Groundwater Monitoring)Groundwater Monitoring1201612QM M2Q quarter 2016 report.docx