A final rule establishing national technology-based effluent limitations guidelines and standards to reduce discharges of pollutants from nuclear and fossil fuel power plants to U.S. waters won’t be issued until at least September 2015, the Environmental Protection Agency (EPA) has confirmed. 

This April, the agency and environmental groups Defenders of Wildlife and the Sierra Club agreed to amend the consent decree to extend the schedule for completion of the final rulemaking by nearly 16 months beyond the original May 22, 2014, legal deadline. The final rule is now expected before Sept. 30, 2015.

The plaintiffs in the case Defenders of Wildlife v. EPA (No. 1:10-cv-01915-RWR) agreed to the deadline extension “with the understanding” that the EPA has committed in a separate case (Appalachian Voices et al. v. McCarthy[No. 1:12-ev-00523-RBW]) to issue a final revision of the Resource Conservation and Recovery Act (RCRA) subtitle D by Dec. 19, 2014. That revision, which is expected to establish the first-ever federal regulations for coal combustion residuals, would apply to many of the same facilities covered under the EPA’s proposed effluent limitations rule.

The EPA’s April 2013–proposed revisions to the steam electric power plant effluent guidelines stem from a 2009 study, in which the EPA found that current rules, last updated in 1982, do not “adequately” address the pollutants being discharged and have not kept pace with changes that have occurred in the power sector. The final rule will likely address discharges associated with coal ash waste and flue gas desulfurization air pollution controls, as well as other power plant streams. Pollutants of concern include metals—including mercury, arsenic, and selenium—nutrients, and total dissolved solids.

But they could come at a cost of between $185.2 million to nearly a $1 billion a year, the agency has admitted. The Office of Management and Budget prioritizes the rule as “economically significant.”

The requirements incorporated into National Pollutant Discharge Elimination System (NPDES) discharge permits issued by the EPA and the states apply to steam power plants using nuclear or fossil fuels, including coal, oil, and natural gas. The proposed rule would cover about 1,200 power plants nationwide.