ARCHIVED REPORTS_COMBINED ANNUAL AND SECOND-HALF 2012 GROUNDWATER MONITORING REPORT 01-31-2013

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INFORMATION SHEET 2 WASTE DISCHARGE REQUIREMENTS ORDER R5-2012-0105 DIAMOND PET FOOD PROCESSORS OF RIPON, LLC AND RIPON COGENERATION, LLC DIAMOND PET FOOD RIPON FACILITY SAN JOAQUIN COUNTY brine has been diluted with low TDS groundwater before being discharged to the LAAs; the effluent had an average TDS concentration of 526 mg/L from May 2010 through June 2011. The wastewater treatment facility consists of a solids separation system, a clarifier, two aeration stabilization basins (ASB-1 and ASB-2) operated in series, and 86 acres of percolation fields and orchards (Land Application Areas, "LAAs"). ASB-1 and ASB-2 are equipped with mechanical aerators. In addition, Ponds 1 through 4 are used only to contain excess wastewater in case of treatment system upset or to store storm water runoff during the wet seasons. Storm water collected in the ponds is applied to the LAAs and no storm water runoff is discharged to surface waters. There are two closed paper mill sludge disposal units onsite, which have inert paper sludge and are covered with a minimum of one foot thick vegetative soil graded for draining purposes. A site map is shown on Attachment B. The LAAs consist of the east, and upper west and west percolation fields (43 acres), and east, west and north orchards (43 acres). There are no crops on the three percolation fields, but there are eucalyptus and redwood trees on the orchards. The wastewater in ASB-2 is applied to the LAAs via flood irrigation for disposal by percolation. Changes in the Discharge Diamond uses dry ingredients, oils, fats and fresh meat to manufacture 250,000 tons of pet food each year. Diamond proposed to start manufacture in April 2012 and to discharge wastewater into the onsite wastewater treatment system, and is currently operating at approximately 60 percent of production capacity. With the exception of the wastewater facilities, the paper mill manufacturing facilities have been removed and restructured for pet food manufacture. Diamond does not propose to improve the existing wastewater treatment facility. However, the projected wastewater flow rates and quality are different from the previous paper mill's discharge. Diamond uses RO systems to improve the quality of the groundwater supply that is used for its processes. Diamond's wastewater consists of the RO reject brine, and process and sanitation wastewater. In addition, Diamond will continue to accept Ripon Cogeneration, LLC's cooling tower blowdown and RO reject brine. Diamond's process and sanitation wastewater is collected into a solids separation collection system and then the supernatant is pumped into a clarifier. The solids are hauled offsite to a permitted landfill. The wastewater from both Ripon Cogeneration, LLC and Diamond is mixed in the circular clarifier, where wastewater is diluted with low TDS groundwater from the onsite production wells and distilled water purchased from Ripon Cogeneration, LLC. The wastewater flows into two ASBs in series from the clarifier and then is applied to the LAAs via flood irrigation. The wastewater treatment process schematic is shown on Attachment C.