Attorneys for New York state are asking a federal appellate court in Washington, D.C., to invalidate a decision by the Trump administration that declined to identify hundreds of sources of emissions as a contributing factor to smog pollution in New York.

That decision, from the U.S. Environmental Protection Agency, will allow the federal government to forego placing restrictions on those emissions to comply with the Clean Air Act.

State officials had been seeking to compel the federal agency to identify emissions from approximately 350 sources in nine states to the south and west of New York as a contributing factor to unhealthy air quality for several residents.

New York Attorney General Letitia James said more than two-thirds of New York's population, from the New York City metropolitan area and Chautauqua County in western New York state, experience unhealthy air quality.

"More than two-thirds of New Yorkers regularly breathe unhealthy air due to interstate smog pollution, yet the EPA continues to ignore the Clean Air Act," James said. "We will not remain idle when a federal agency called the 'Environmental Protection Agency' routinely refuses to protect the environment or the health of millions of people."

Georgia Pestana, the acting corporation counsel for New York City, and New Jersey Attorney General Gurbir Grewal also signed onto the lawsuit with New York state.

A spokeswoman for the EPA said the agency doesn't comment on pending litigation.

Nine counties in New York are currently considered by the EPA to be out of compliance with federal health standards for smog, according to the Attorney General's Office. Officials from New York state have largely attributed that to pollution from other states.

That's because New York, according to the Attorney General's Office, has some of the strictest air quality regulations in the country. Emissions of pollutants that cause smog are aggressively regulated, which has led to some of the lowest emissions of those toxins nationwide.

Those pollutants, when emitted, can travel hundreds of miles from their source, according to the Attorney General's Office. That means that states upwind of New York, like Illinois and Virginia, can cause higher smog pollution downwind.

The federal Clean Air Act's "Good Neighbor" provision allows the EPA to step in and create plans to curb pollution in downwind states when the actions of upwind states aren't enough to reduce smog elsewhere. That's where New York's petition to the EPA earlier this year comes in.

New York was seeking to have the EPA recognize that emission sources in the nine states it identified were significantly contributing to the state's smog problems. That way, under the Clean Air Act, the federal government could step in and help curb those emissions.

The EPA, in its decision, said it couldn't find evidence, nor was it provided with information, to show that those emission sources were directly causing New York's smog problem.

"The EPA is denying the petition because the petitioner, New York, has not demonstrated, and the EPA did not independently find, that the group of identified sources emits or would emit in violation of the good neighbor provision," the EPA said.

The two-page lawsuit brought against the agency by James on Tuesday is essentially seeking to strike down that finding. The challenge was filed in the U.S. Court of Appeals for the D.C. Circuit.

It's not the first time New York state has brought litigation against the EPA over interstate smog. 

James, leading a coalition of six states and New York City, sued the federal agency in January over a proposed rule that would have allowed states to avoid taking any additional action to curb interstate smog. That rule was vacated by the D.C. Circuit. 

New York state also challenged the EPA's alleged failure to intervene in the planned emission reduction plans of states that were identified in 2015 as not doing enough to curb interstate pollution. 

The decision, handed down in the Southern District of New York, ordered the EPA to address emission levels in states whose pollution traveled into New York. There was no appeal.

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