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

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Diamond Pet Food Processors of Ripon California LLC January 31,2013 Combined Annual and Second-Half 2012 Groundwater Monitoring Report Page 4 of 6 ingredients are delivered in bulk or bagged form. The bagged ingredients will be stored in a dry warehouse. The bulk ingredients will be stored in bins and silos. Fats and oils are stored in liquid tanks within a contained tank farm. The fresh meat is shipped in reusable totes and stored in a cooler room. The dry ingredients first are mixed together in a three-ton mixer, and then transferred to a hammer mill for more extensive grinding to turn into a mash. The mash is then sent to the extrusion process where the fat/oil and fresh meat are added. The extrusion process uses time, temperature, heat and pressure to cook the product. The product is cooked to a minimum of 190°F. This process creates a very small amount of scrap which is reworked or sent to an appropriate disposal facility. 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 consists of Reverse Osmosis (RO)reject water and process/sanitation(cleaning) water. On a maximum day, about 75,000 gallons per day (gpd) is rejected from the RO system and about 12,000 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. 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 DP Plants). The existing wastewater facilities (Sump, Clarifier, 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 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 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 are used only to contain excess wastewater in case of a system upset or a 100-year-or-greater storm event. FORT CHICAGO US. POWER COGENERATION PLANT The adjacent cogeneration plant historically has routed blowdown through the DP facilities wastewater system, and will continue to do so until 2017. Flows (2009 and 2010) have been between 200,000 and 300,000 gallons per day but in the fourth quarter 2012 average flows ranged between 55,788 and 137,444 gallons per day. The most recent (October 2012) TDS value for Cogen flow was 828 mg/L; previously in 2010 TDS in the Cogen discharge ranged between 500 and 1,200 mg/L. Historically, the Cogen 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 10107.01 Task 8 Lawrence&Associates W.•I CLIENTSIDiamond Pet Foods1010107.01-Groundwater Monitoringl Groundwater Monitoring1201214Q201214TH QUARTER Annual 2012.docx