Duke Energy's Cliffside Coal Plant in North Carolina.

Rainforest Action NetworkBeware, neighbors.

It’s been a week of refreshing news for fans of unpolluted air. As Barack Obama on Tuesday was calling for greenhouse gas limits on power plants, clean air advocates were also celebrating a decision by the Supreme Court to hear an important case on power-plant pollution.

The EPA’s Cross-State Air Pollution Rule was designed to cut down on life-threatening power-plant pollution that blows across state borders. It called for reductions of sulfur dioxide and nitrogen oxide emissions at power plants in 28 states in the eastern U.S. The rule would mostly affect coal power plants, the dirtiest of America’s electricity plants. The EPA and supporters of the rule have said it would save tens of thousands of lives every year.

But owners of dirty power plants and some of the states in which they operate argued in court that the rule goes farther than the EPA is allowed to go under the Clean Air Act’s “good neighbor” provision.

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Last August, the notoriously conservative U.S. Court of Appeals for the D.C. Circuit ruled 2-1 in favor of the power plant companies, striking down the EPA’s rule.

But now the Supreme Court will hear the case and could reverse the circuit court’s ruling. From Reuters:

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At the request of the administration, the American Lung Association and environmental groups, the [Supreme Court] justices will revisit an appeals court ruling that invalidated the Cross-State Air Pollution rule, which the EPA implemented to enforce a provision of the Clean Air Act.

Oral arguments and a decision are due in the court’s next term, which starts in October and ends in June 2014.

“The decision vaults the Cross-State Air Pollution Rule into the top five Clean Air Act cases heard by the Supreme Court,” said John Walke of the Natural Resources Defense Council.

The ultimate ruling on this case won’t generate as much press as the Supreme Court’s heartening gay-marriage decisions, or disheartening Voting Rights Act decision, but it could save a lot of lives.