The U.S. Environmental Protection Agency’s proposal to add phosphorus as a major contaminant of concern at the J.R. Simplot Co.’s phosphate fertilizer plant west of Pocatello could end up costing Simplot $50 million in cleanup costs to minimize discharges into the nearby Portneuf River.
EPA held meetings in Pocatello and Fort Hall March 17-18 to allow public comment on the proposal. It estimates that water flows through a 320-acre gypsum stack behind Simplot’s Don Plant at about 1,000 gallons a minute and later reaches the Portneuf via springs and an underflow, causing overgrowth of algae and dissolving oxygen levels for fish and other aquatic life. Waste material from phosphoric acid production is pumped onto the gypsum stack.
Operational changes also need to be implemented to reduce the Don Plant’s contaminant discharges, including heavy metals, from leaching into groundwater and the river, according to EPA.
“Simplot already is proactively moving forward with plant actions,” said Kira Lynch, EPA regional project manager, noting EPA will be working closely with Simplot the next six to nine months to raise the subsurface pH level so contaminants can be better absorbed in the soil. Last fall, Simplot spent about $4 million on plant upgrades, she said.
Lynch said EPA doesn’t believe an extraction wells system alone will reduce Simplot’s phosphorus load to the Portneuf River by 80 percent as agreed in a 2003 implementation plan. Some hot spots are 100,000 times higher than the concentrations needed to achieve that reduction, she said.
EPA recommends that Simplot install a high-density polyethylene liner atop the gypstack to help reduce contaminated water infiltration. That would be done in three phases, starting in 2010 and concluding by 2014. Initial surge pond construction should begin this year.
In the past, phosphorus often has not been regulated as a contaminant because it has been considered a nutrient fertilizer, said Bruce Olenick, the Idaho Department of Environmental Quality’s regional administrator. EPA, IDEQ, the Shoshone-Bannock Tribes, and Simplot will cooperate in amending the Record of Decision to include phosphorus as a contaminant of concern. A public comment period expires on April 15.
A 1998 EPA Record of Decision identified a number of contaminants under the plant site, including arsenic, boron, chromium, mercury, nickel, radium, vanadium, and zinc. Phosphorus wasn’t included because it was presumed extraction wells designed to meet federal drinking water standards for arsenic would sufficiently address phosphorus.
The Simplot plant sits on the Eastern Michaud Flats Superfund Site, which encompasses 2,475 acres and includes the adjacent FMC elemental phosphorus plant that closed in December 2001. Groundwater under the site contains contaminants of concern from both phosphate factories.
EPA cites the Simplot plant as the primary contributor of phosphorus to the Portneuf River, contributing about 82 percent of the total maximum daily load. The Portneuf contributes about 65 percent of the phosphorus load that flows into the American Falls Reservoir downstream, or about 387 tons per year, as opposed to the Snake River, which infuses about 167 tons per year into the reservoir.
The Portneuf River at Siphon Road has the highest concentration of phosphorus of any site in Idaho at between 900 and 1,000 parts per billion, as opposed to the federal standard of 75 ppb ?Çô far exceeding levels in the Snake River at Blackfoot and Hells Canyon, the Boise River at Parma, and the Spokane River on Idaho’s border with Washington state. The standard may soon be set at 70 ppb.
Lawrence Gebhardt of Pocatello urged EPA and Simplot to look at securing federal stimulus funding to ease the financial burden on Simplot and soften the impact on the Don Plant’s viability and jobs in the region.
Annual wages and salaries paid at Simplot’s Don Plant and its Smoky Canyon phosphate mine near Idaho’s Wyoming border exceed $52 million. About 375 are employed at the Pocatello plant, while there are approximately 200 workers at the mine. Another estimated 1,450 people are indirectly employed by the operations, whose annual property taxes exceed $3 million.