The U.S. Environmental Protection Agency (EPA) and the U.S. Department of Justice (DOJ) this week announced a settlement with Mosaic Fertilizer LLC that will ensure the proper treatment, storage, and disposal of an estimated 60 billion pounds of hazardous waste at six Mosaic facilities in Florida and two in Louisiana.

The settlement resolves a series of alleged violations by Mosaic, one of the world’s largest fertilizer manufacturers, of the federal Resource Conservation and Recovery Act (RCRA), which provides universal guidelines for how hazardous waste must be stored, handled and disposed. The 60 billion lb of hazardous waste addressed in this case is the largest amount ever covered by a federal or state RCRA settlement.

At Mosaic’s eight facilities in Florida and Louisiana, hazardous waste from fertilizer production is stored in large piles, tanks, ditches and ponds; the piles can reach 500 ft high and cover more than 600 acres, making them some of the largest manmade waste piles in the United States.

Under the settlement, Mosaic Fertilizer will establish a $630 million trust fund, which will be invested until it reaches full funding of $1.8 billion. These funds will cover the future closure of and treatment of hazardous wastewater at four Mosaic facilities—the Bartow, New Wales and Riverview plants in Florida and the Uncle Sam plant in Louisiana—as well as the long-term care of those facilities and three additional facilities that are already undergoing closure. Mosaic will provide financial guarantees for this work, and the settlement also requires Mosaic Fertilizer to submit a $50 million letter of credit.

The alleged violations stem from storage and disposal of waste from the production of phosphoric and sulfuric acids, key components of fertilizers, at Mosaic’s facilities in Bartow, Lithia, Mulberry and Riverview, Florida and St. James and Uncle Sam, Louisiana. Mosaic failed to properly treat, store, and dispose of hazardous waste, and also failed provide adequate financial assurance for closure of its facilities.

As part of the EPA’s National Enforcement Initiative for mining and mineral processing, the agency has required phosphate fertilizer production facilities to reduce the storage volumes of hazardous wastewaters, ensure that waste piles and ponds have environmentally protective barriers installed, and verify the structural stability of waste piles and ponds.

Mosaic has committed to spending approximately $170 million over the next several years to implement an innovative reconfiguration of their current operations and waste management systems. The development of these technologies will optimize resource efficiency and decrease the amount of raw materials required to produce fertilizer. This case spurred Mosaic to develop advanced engineering controls and practices to recover and reduce some types of acid wastes that result from fertilizer production, which will reduce the amount and toxicity of the waste materials stored at Mosaic’s facilities and the severity of potential spills while cutting Mosaic’s costs for treating material at closure, which would otherwise have been categorized as hazardous waste.

Mosaic will also spend $2.2 million on two local environmental projects. Mosaic will also pay a $5 million civil penalty to the United States and $1.55 million to the state of Louisiana and $1.45 million to the state of Florida, who joined the EPA and DOJ as plaintiffs in this case.