The U.S. Supreme Court has given the Environmental Protection Agency an important victory in its effort to reduce power plant pollution that contributes to unhealthy air in neighboring states.
The court's 6-2 decision means that a rule adopted by EPA in 2011 to limit emissions from power plants in more than two-dozen states including Oklahoma can take effect.
The pollution drifts into the air above states along the Atlantic Coast and the EPA has struggled to devise a way to control it.
Public Service Company of Oklahoma says with Tuesday's decision, the utility expects no change in its existing plan to comply with the Regional Haze Rule agreement it reached with the EPA in 2012.
PSO spokesman Stan Whiteford says Tuesday's decision deals with the Cross-State Air Pollution Rule which was different from the Regional Haze Rule.
He says the reductions and plant retirements already planned under the Regional Haze Rule will allow the electric utility to achieve the emission reductions required under the Cross-State Air Pollution Rule.
Power companies and several states sued to block the rule from taking effect, and a federal appeals court in Washington agreed with them in 2012.
Justice Ruth Bader Ginsburg wrote the court's majority opinion. Justices Antonin Scalia and Clarence Thomas dissented.
The Associated Press contributed to this report.