ARCHIVED REPORTS_THIRD QUARTER 2017 GROUNDWATER MONITORING REPORT

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Diamond Pet Food&Ripon Energy October 25,2017 Third-Quarter 2017 Groundwater-Monitoring Report Page 3 of 5 screened twice before it is moved to packaging. The screeners clean the product, taking off very fine pieces and mis-formed kibbles. The fines and mis-formed kibble are reworked. The product is stored in overhead bins in the warehouse until it is packaged. The product is tested in packaging and at other steps throughout the process. If the product is not within specifications, it is rejected and reworked within the process. Wastewater from the Plant consists of Reverse Osmosis (RO)reject water and process/sanitation (cleaning) water. On a maximum day, about 75,000-gallons per day(gpd) are rejected from the RO system and about 12,000-gallons are generated as process and cleaning 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-1 then ASB-2). The first pond, ASB-1, is approximately 14-feet deep and is lined; the third, 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 1 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 2016 were between 1,233 and 33,213 gallons per day and the total volume of water discharged in 2016 was 4,105,392 gallons.3 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-1 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 a directive from the CVRWQCB to evaluate the impacts of effluent disposal on groundwater quality. 3 L&A,January 31,2017, Combined Annual and Fourth-Quarter 2016 Groundwater-Monitoring Report,Diamond Pet Food Processors of Ripon,LLC and Altagas Ripon Energy,Inc. Ripon, California. 010107.09 Task 3 Lawrence&Associates KCLIENTSIDiamond Pet Foods 1010107.01-Groundwater Monitoring)Groundwater Monitoring1201 713Q201 713Q quarter 2017 report.docx