WASHINGTON - A federal appeals court yesterday threw out a Bush administration rule that blocked states from stricter monitoring of air pollution from oil refineries and power plants.

The U.S. Court of Appeals for the District of Columbia Circuit ruled in a 2-1 decision that a 2006 rule barring states from supplementing Environmental Protection Agency monitoring standards was invalid.

The EPA issued the regulations in 2006 to encourage investment in energy infrastructure by streamlining the permit process. Environmental groups said the regulations allowed oil companies and electric utilities to bypass state and local emissions laws.

"We vacate this rule because it is contrary to the statutory directive" that each permit issued must include adequate monitoring requirements, Judge Thomas Griffith wrote for the court.

Because federal monitoring rules are often inadequate, state and local governments must be allowed to set their own standards to augment the federal Clean Air Act, wrote Griffith, an appointee of President Bush.

Joining Griffith's opinion was Chief Judge David Sentelle.

"This is a huge victory against one of the most egregious rollbacks of environmental protections in our nation's history," said Carl Pope, executive director of the Sierra Club, the environmental lobbying group that brought the suit. "Public health should be a top priority, not polluters' profits."

EPA spokesman Dale Kemery said in an e-mail that the department was reviewing the decision and had no immediate comment.

In dissent, Judge Brett Kavanaugh said EPA rules should trump local laws.

The court ruled last month that the EPA went beyond its authority in 2005 when it created the Clean Air Interstate Rule, which reduces allowable emissions of sulfur dioxide and nitrogen oxide from power plants.

The case is Sierra Club v. Environmental Protection Agency.