Snow and freezing rain fall on the Supreme Court and Capitol in Washington, early Tuesday. (J. Scott Applewhite/AP)

Supreme Court justices seemed inclined Tuesday to resurrect Environmental Protection Agency rules targeting air pollution that drifts across state borders, one of the Obama administration’s major environmental targets.

The government for years has struggled to implement a directive under the federal Clean Air Act to protect downwind states from pollution generated in other states, mostly from coal-fired power plants.

The latest effort to address the “good neighbor” provisions was due to go into effect in January 2012. But a divided panel of the U.S. Court of Appeals for the D.C. Circuit, acting on a challenge brought by 14 of the upwind states and a coalition of industry interests, rejected the plan and said the EPA had exceeded its authority.

The government appealed and appeared to get a better reception from the eight justices who participated in Tuesday’s oral arguments. (Justice Samuel A. Alito Jr. recused himself from the case.)

The four justices who usually make up the court’s liberal contingent spoke forcefully in favor of EPA’s rulemaking powers, and both Chief Justice John G. Roberts Jr. and Justice Anthony M. Kennedy at times indicated they believed the law gave the agency broader leeway than the challengers alleged.

Only Justice Antonin Scalia indicated he believed the EPA had exceeded its power.

The Cross-State Air Pollution Rule affects mostly the eastern two-thirds of the country and requires power plants in more than two dozen states to clean up nitrogen oxide and sulfur dioxide pollution that contribute to soot and smog elsewhere.

According to the EPA, eliminating the pollution would prevent 13,000 to 34,000 premature deaths and 15,000 non-fatal heart attacks as well as decrease emergency room visits and the number of respiratory disease episodes.

Despite the dramatic topic, the discussion was dauntingly complex; Roberts seemed to sum up the complicated arguments when he referred to the “spaghetti matrix or something” mentioned in the government’s brief.

It reads: “The interstate pollution problem is best understood as a dense, spaghetti-like matrix of overlapping upwind/downwind ‘linkages’ among many states, rather than a neater and more limited set of linkages among just a few.”

The coal industry and the challenging states have characterized the EPA rules as a vast overreach and unlawful usurpation of states’ rights.

But Deputy Solicitor General Malcolm L. Stewart countered that the agency was only trying to implement the Clean Air Act and serve as an “honest broker” between competing state interests.

“It’s true that by devising a federal plan in the first instance, EPA has intruded to a degree on the ability of the upwind states to decide” how to reduce their emissions to acceptable standards, Stewart said.

“But the downwind states are subject to their own obligations to comply with (air quality standards) within their own borders, and to the extent that they can’t get relief from the upwind states their task is made more difficult.”

Because the case is being heard by only eight justices — as is customary, Alito did not give a reason for sitting out the case, although usually it is because of a financial conflict — a tie vote would leave the D.C. Circuit’s ruling in place and send the EPA back to the drawing board.

The combined cases the court heard are EPA v. EME Homer City Generation and American Lung Association v. EME Homer City Generation.