Hot and heavy - that's the air of mid-July. Hot and heavy also is the legal action on clean air rules that directly involve North Carolina.

The bottom line is problematic for the air we breathe, at least in the short run. Despite well-intentioned efforts by state government, public health here and throughout the eastern U.S. is likely to suffer from new delays in cleaning up power-plant pollution. As a result, state officials must make sure North Carolina's clean-air rules are being enforced, and Congress should update the federal rules.

On Friday, a federal appeals court rejected the U.S. Environmental Protection Agency's 2005 Clean Air Interstate Rule (CAIR). The case involved pollutants that create soot and smog, notably nitrogen oxides and sulfur dioxide.

Meanwhile, North Carolina's attorney general, in a trial just starting in Asheville, is suing the Tennessee Valley Authority over emissions from TVA coal-burning power plants in states to our south and west. Attorney General Roy Cooper seeks to force the TVA to reduce pollution that cuts visibility and harms North Carolinians' health.

The state isn't asking the TVA to do anything it isn't already requiring of utilities here under North Carolina's 2002 Clean Smokestacks Act. Improved technology can scrub more of the pollutants from coal-fired plants. Besides, cleaning up smokestacks in Alabama, Kentucky and Tennessee will help people in those states too.

It was because of its pioneering Clean Smokestacks Act that North Carolina joined a lawsuit against the Clean Air Interstate Rule. The state's complaint was that a "cap-and-trade" emission control program in CAIR wasn't tough enough, because it allowed out-of-state utilities to buy credits that would let them continue polluting. Carried here by the winds, that pollution would undercut the Clean Smokestacks Act.

Charlotte-based Duke Energy also sued. Its aim was not to overturn the cap-and trade provision but to improve its own treatment under that provision.

The U.S. Court of Appeals for the District of Columbia, however, found no room for "tinkering" with a "fundamentally flawed" cap-and-trade system. The EPA's regionally based approach, a three-judge panel said in rejecting the rule, went adrift in failing to set state-specific emissions requirements. It's not clear whether there will be an appeal.

CAIR may have been the Bush administration's most aggressive action to clean the air. Still, a more determined approach would have saved valuable time and better protected North Carolina's air, benefiting many people affected by air pollution.

The alignments and alliances in the CAIR case were unusual, with environmental groups joining several power companies in support of the EPA, with Duke Energy seeking a better cap-and-trade deal although not trying to overturn the rule itself, and with North Carolina pressing for tougher controls.

Yet the outcome was a sweeping ruling that could well delay progress until after the elections, leaving a thin air-quality legacy for the Bush administration. A new Congress and president should quickly establish viable rules. Meanwhile, North Carolina has its Clean Smokestacks law to enforce -- and now a federal court ruling has ratified the state's commitment to clean air. The TVA could help by joining in.

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