The Supreme Court on Tuesday agreed to rule on an Environmental Protection Agency mandate to limit mercury and other air pollutants from power plants, threatening to upend a key part of Obama administration’s environmental agenda.
A federal appeals court in April denied challenges to the Mercury and Air Toxics Standards, or MATS, which are slated to go into effect in May. The rule would force some of the nation’s 600 dirtiest coal and oil-fired power plants to shut down or install new technology to curb emissions.
The EPA says the MATS rule would significantly curb mercury emissions from coal and oil-fired power plants that, as the largest source of such pollution, account for 50 percent of the nation’s total mercury emissions. It also would slash emissions of other heavy metals, such as arsenic and nickel, that have been linked to cancer and heart and respiratory ailments.
Opponents, including the electric utility industry and congressional lawmakers from coal states, counter that the rule could shutter so many coal-fired power plants that it would handicap the industry’s ability to meet unexpected demands in power.
The high court, in a brief order, said it agreed to consider appeals of whether the EPA “unreasonably refused to consider costs in determining whether it is appropriate to regulate hazardous air pollutants emitted by electric utilities.”
The agency has said the benefits of cleaner air outweigh the costs of modernizing power plants.
Coal and oil-fueled power plants already are subject to federal regulations under the 1960s-era Clean Air Act. But Congress has told the EPA it can also consider additional regulations for those facilities when “appropriate and necessary.”
Oral arguments likely will take place in March, with a decision expected before the court’s current term ends in late June.
