ARCHIVED REPORTS_RPT OF WASTE DISCHARGE FOR WASTEWATER DISPERSAL 2011

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REPORT OF WASTE DISCHARGE- APPENDIX D Diamond Pet Food Processors of Ripon,LLC June 30,2011 Report of Waste Discharge—Antidegradation Analysis Page 11 of 14 POTENTIAL FOR IMPAIRMENT OF GROUNDWATER The potential for impairment of groundwater would come from infiltration of the wastewater applied to the irrigation fields and leakage through ASB-2. The potential for groundwater impairment was evaluted using the existing groundwater model for the site and by calculating the mass loading of TDS from facility operations. The groundwater model previously was developed for the site to evaluate alternatives for corrective action for impacts related to dispersal of wastewater from the Neenah Paper Company and Fox River Paper Company. Appendix B contains a description of the model. Previous and current site activities (dispersal of paper-mill process wastewater mixed with cogen blowdown), and vicinity discharges (City of Ripon WWTP ponds,Nestles' spill), have affected groundwater quality. Historic discharge at the site contributed about 8,100 lbs/day of TDS to the semiperched aquifer(about 1,187,000 gpd at a TDS of about 814 mg/L). Recently (second-half 2010), after paper-mill operations ceased, TDS loading (from operation of the cogen and mixing groundwater with that effluent) has been about 2,000 lbs/day (about 429,000 gpd at a TDS of about 565 mg/L). The proposed operation,plus cogen discharge, will contribute approximately 3,050 lbs/day of TDS to the semiperched aquifer(about 455,000 gpd at a TDS of about 800 mg/L). The proposed operation, without the cogen discharge (after 2017), will contribute approximately 900 lbs/day of TDS to the semiperched aquifer(about 159,000 gpd at a TDS of about 660 mg/L). This is almost 10 times less than the previous paper-mill operations, and is about one-third the amount of the TDS imparted from the combined Diamond and cogen operations. Figures 18 through 29 show the results of the groundwater modeling, for the three aquifers before and after the cogen ceases water-cooled operation. Note that the groundwater model shows results as concentration rather than mass. Figures 18, 19, and 20 show results for the end of the period in which Diamond and the cogen as a water-cooled facility will operate (six years, or 2017). This scenario assumes that the eucalyptus grove remains in place. In this scenario, about 455,000 gpd of wastewater with a TDS of about 803 mg/L is applied to the fields. The model predicts that most of the semiperched aquifer will be in compliance with the WQPS at the point of compliance (property boundary), except for the area of the eucalyptus grove (Figure 18). The upper aquifer is predicted to be in compliance with the WQPS (1,030 mg/L). The model predicts that the intermediate aquifer remains out of compliance with the WQPS (470 mg/L). 010070.00, Task I Lawrence&Associates w:I clients)diamond pet foods1010107.00-ripon rowdldiamondpet_rowdjune2011_draft.docx