WASHINGTON - The Supreme Court agreed yesterday to consider a plea to curtail the government's authority to require industries to clean up the nation's air - just one week after agreeing to hear a request to broaden that power.
Both sides of the Environmental Protection Agency's authority to enforce the Clean Air Act will be decided in the court term that starts in October. The court said it would hear the two appeals in back-to-back hearings.
The court gave no explanation for widening its review of the Clean Air Act, but it appeared that the justices wanted to explore that complex law from end to end.
In the past, the court had refused four times to clarify the key parts of the law.
Then, last week, it voted to hear an EPA appeal.
It held over until this week an appeal filed by the American Trucking Associations, the U.S. Chamber of Commerce, the National Association of Manufacturers and other business alliances. Then, in a brief order yesterday, it agreed to hear that appeal, too.
The EPA's appeal will test whether that agency has wide discretion to set tougher curbs on two kinds of air pollution - the ingredients of smog, especially ground-level ozone, and the tiny particles of soot from industry smokestacks.
A federal appeals court ruled in 1998 that the EPA had acted unconstitutionally in assuming such sweeping powers to impose new air-quality standards for those forms of pollution.
The EPA smog and soot rules were the most expensive controls the agency had ever sought to impose.
The business groups' appeal will test whether the EPA, in considering new standards, must take into account the effect that reducing human exposure to pollutants would have on industry costs.
The appeals court ruled against that interpretation of the Clean Air Act.
It said the only factor the law allows the EPA to consider is the effect that the new standards would have on public health.