Comments sought on Simplot permit

Boise — The Idaho Department of Environmental Quality (IDEQ) is seeking public comment on a draft wastewater reuse permit renewal for the J.R. Simplot Co.’s fertilizer complex west of Pocatello, where phosphate ore is processed into dry and liquid phosphate and nitrogen fertilizers, feed phosphates, and purified phosphoric acid. The permit authorizes the company to continue operating a wastewater treatment and reuse system, allowing treated industrial wastewater to be used for irrigating about 1,545 acres of crops during the growing season from April 1 to Oct. 31. The Simplot Don Plant continues to operate under terms of the IDEQ permit issued in June 2002. The plant applied 542 million gallons of wastewater to its permitted management units during the 2009-2010 season, including supplemental irrigation water from a surge pond well. Two areas close to the plant and sites north of Pocatello receive the wastewater, which is piped beneath Highway 30 to a pond complex directly north of the plant. As part of the permitting process, the company is required to show how it will continue to address health and environmental concerns, including methods of preventing contamination of surface and ground water. Industrial wastewater, consisting of collected storm water, cooling water, demineralizer regeneration water, ore silo decant water, and minor isolated plant cleanup discharges can be applied to land, but the permit prohibits applying other sources of wastewater, including gypsum stack decant water, extraction well water, or other waste streams not identified in the permit. The draft permit specifies buffer zones, loading rate limits, and monitoring requirements established by IDEQ to protect public health and the environment. The Don Plant has reduced water use within the plant, the state agency reports. During a recent inspection, plant personnel showed that from August 2001 to 2011, the plant reduced wastewater production by 53 percent and continues to find ways to further reduce water use. It also reduced wastewater nitrogen content during that period. Written comments on the draft permit will be accepted through Tuesday, Nov. 13. The draft permit and staff analysis are available for public review at IDEQ’s Office in Pocatello and on IDEQ’s web site.