WASHINGTON: Industry groups are celebrating one of their most significant court victories in years following the May 14 decision by a federal appeals court to strike down EPA's toughened air-quality standards. In a case brought by the American Trucking Assns. and an array of other business groups, the U.S. Court of Appeals for the District of Columbia Circuit ruled that the standards are unconstitutional because EPA "failed to state intelligibly" how much pollution "is too much." The court also said that the standards represented an unconstitutional delegation of legislative authority. EPA issued the standards, which tighten emissions requirements of particulate matter (soot) and ground-level ozone (the principaln ingredient of urban smog), in 1997. Over the course of their implementation, they were expected to add billions of dollars to industry's environmental-compliance costs. "This ruling strikes right at the heart of EPA's abuse of regulatory authority -- and that's a big win for businesses large and small," observes Thomas J. Donohue, president and CEO of the U.S. Chamber of Commerce. "This ruling will force the EPA to regulate according to clear standards. They can't just pick numbers out of thin air." Adds G. William Frick, vice president and general counsel of the American Petroleum Institute" "The decision gives EPA another opportunity to fully take into consideration the recommendations of its own Clean Air Scientific Advisory Committee." The panel, he notes, had urged the agency to implement a targeted research program "to address the many unanswered questions and scientific uncertainties" before issuing the standards. EPA immediately indicated it will appeal the decision, which ultimately is expected to land in the Supreme Court.