The Supreme Court will hear arguments Monday about the Environmental Protection Agency's first-ever greenhouse gas regulations for the biggest polluting facilities.

The case focuses on a 3-year-old requirement that companies get permits anytime they construct new plants or modify existing ones that will emit a lot of greenhouse gases.

EPA's supporters and most of its challengers agree this case is narrow in scope; the court's ruling is not expected to threaten EPA's broader strategy to fight global warming.

Some industries challenging these permits argue that what they require can be costly and time consuming. They contend that the EPA contorted a provision of the Clean Air Act to make it fit greenhouse gases.

"The law passed by Congress said that anyone who emits more than 250 tons a year of a pollutant needs a permit, and EPA said that would be absurd, that [it] would lead to an absurd result," says Jeffrey Holmstead, an industry lawyer who headed the EPA's air pollution programs under President George Bush. Holmstead is a critic of EPA greenhouse gas permitting.

Even a small facility can pump out 250 tons of greenhouse gases in a year, so to avoid having to issue permits for tens of thousands of new buildings, the EPA basically modified the law so that it applies only to big factories.

Industry officials weren't satisfied with that. Neither were some states.

"If it's that absurd that you have to go through that many somersaults to make the thing remotely rational, then maybe you've misinterpreted the statute to begin with," says C. Boyden Gray, an attorney representing some states in this case.

Gray says the states he represents worry that the EPA in the future will start requiring smaller facilities to get permits, and that even churches and apartment houses might need to get them.

"Eventually the nightmare will unfold," Gray says.

Environmental groups criticize the industry's challenge and stress that the Supreme Court traditionally gives broad deference to the EPA to interpret the Clean Air Act.

"It's a very legalistic argument that's designed to prevent EPA from protecting America's families and communities from climate pollution," says Vickie Patton, an attorney for the Environmental Defense Fund.

Some companies that have gotten greenhouse gas permits without much trouble also reject the industry's arguments in this case.

Calpine Corp. — which has six such permits for power plants in California, Texas and Delaware — defends the program in a legal brief filed with the Supreme Court.

"We haven't found this permitting program to be overly cumbersome or expensive. We haven't seen any significant increase in permitting time really," says Derek Furstenwerth, Calpine's senior director for environmental services.

Calpine has not had to buy expensive new pollution control equipment to get the permits, Furstenwerth says. It just had to build plants that will get the most electricity out of the fuel they burn.

"So it winds up that the permitting process and our economic interests in building the plants are pretty well aligned," Furstenwerth adds.

In the past three years, permits have been issued for 141 facilities nationally, according to the EPA.

The EPA declined NPR's requests for an interview. In an email, the agency said the permit program has been "running smoothly," with most companies complying by making their facilities more energy efficient. The agency says it currently has no plans to require permits from smaller facilities. A review of the program is due next year; after that, the agency may revisit the question of how much greenhouse gas pollution would trigger the need for a company to get a permit.

Under President Obama, the EPA already has curtailed emissions from cars and trucks. Still to come are EPA rules aimed at reducing greenhouse gases from new and existing power plants.

"This case is not about EPA's authority to address climate pollution under the nation's clean air laws," says the Environmental Defense Fund's Vickie Patton.

"This is a very narrow case," says Jeffrey Holmstead, the industry attorney. "I think the outcome won't have much of an impact one way or another on EPA's ability to regulate carbon."

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