The Supreme Court is back in session, and Environmental Protection Agency emissions regulations are on the docket.

The court will hear a case challenging EPA regulations of greenhouse gas emissions from stationary sources like power plants, The New York Times reports.

However, the justices declined to hear any petitions challenging the EPA's regulation of motor vehicle emissions, leaving that authority intact regardless of the outcome of the current case.

The more limited case the court will hear is a sequel to Massachusetts v. Environmental Protection Agency, a 2007 case that required the EPA to regulate new vehicle greenhouse gas emissions if it found that they endangered public health and welfare.

Not surprisingly, the agency found just that and in 2009 issued regulations limiting emissions from both new vehicles and stationary sources.

The case questions whether the EPA can really regulate stationary sources the way it regulates cars.

The question being considered is whether the EPA's regulation of vehicle greenhouse gas emissions "triggered permitting requirements under the Clean Air Act" for stationary sources, the Times reported.

Geothermal Power Plant in Iceland

Geothermal Power Plant in Iceland

The groups challenging the regulations--including elements of the oil and chemical industries--claim the regulations hurt economic competitiveness.

Harry Ng, vice president and general counsel for the American Petroleum Institute, told the Washington Post that the EPA's climate change authority constitutes over-regulation of U.S. manufacturing.

Environmentalists emphasized the regulations the Supreme Court didn't touch.

Vickie Patton, general counsel for the Environmental Defense Fund, said the court's limiting of the case proved the validity of the EPA's existing regulations on greenhouse gas emissions from cars and trucks.

With EPA regulations like the 54.5 mpg gas mileage standard untouched, the next emissions battle may very well be over stationary sources.


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