ARCHIVED REPORTS_RPT OF WASTE DISCHARGE FOR WASTEWATER DISPERSAL 2011

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Diamond Pet Food Processors of Ripon,LLC June 30,2011 Report of Waste Discharge Page 3 of 17 The product is sent from extrusion to a dryer, where it is dried for about 30 minutes. The product then moves to a series of coaters that apply fat/oil and natural flavors. The product is 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 will consist of Reverse Osmosis (RO) reject water and process/sanitation (cleaning)water(Table 1). On a maximum day, about 75,000 gallons per day(gpd)will be rejected from the RO system and about 12,000 generated as process and cleaning water. This level of discharge will be rare, occurring for one day at time very occasionally. According to Diamond personnel, the maximum discharge reflects operation of all four production lines which rarely occurs. Average discharge will be about 75% of this (56,250 gpd of RO reject water and 9,000 gpd of process/sanitation water), at full buildout(typically, only 3 of the 4 manufacturing systems operate in Diamond Plants). Figure 3 shows a process diagram of the proposed water/wastewater routing system. The existing wastewater facilities (Sump, Clarifier,Aeration Stabilization Basin (ASB) #1, ASB #2, and irrigation piping)will continue to be used to treat the wastewater through aeration and disperse it. Effluent from the Clarifier will be discharged into the two aeration stabilization basins in sequence (ASB-1 and 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 then will be pumped to 86 acres of fields and orchards around the site. Other ponds on the site (labeled Ponds 1 through 4) are unlined and will be used only to contain excess wastewater in case of a system upset or a 100-year- or-greater storm event. The site also contains two inactive closed sludge disposal units! The unit previously designated "Active Sludge Disposal Impoundment" is in the process of being closed by filling in the impoundment with clean fill, regrading the surface for positive drainage, and revegetating. 1 Lawrence&Associates,December 28,2010, Work Plan for Sludge Impoundment Closure,Diamond Pet Food Plant, Ripon, California. 010107.00, Task I Lawrence&Associates w:Iclientsl diamond pet foods1010107.00-ripon rowdldiamondpet_rowdjune2011_draft.docx