Despite strong objections from some of the nation's top manufacturers, the Bush administration this week is expected to toughen the standards for reducing air pollution in communities nationwide.

The Environmental Protection Agency is under court order to update the air quality rules by Wednesday. The announcement could be among the last major environmental decisions under President Bush.

Ben Gray/AJC (ENLARGE)

Gov. Sonny Perdue said new rules could be 'disruptive' of local efforts to improve air quality.

T. Levette Bagwell/AJC (ENLARGE)

Saxby Chambliss was one of several U.S. senators to declare changes 'unnecessary.'

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Tighter standards would require cities and counties to step up efforts against ground-level ozone, which comes from factory smokestacks, cars, trucks and electric utilities. Such ozone is linked to lung diseases, especially in children and the elderly.

The National Association of Manufacturers mobilized local business groups and more than a dozen governors, as well as Republican lawmakers, for an intense lobbying effort against changing the air quality rules.

A new standard "is completely unnecessary," said Republican Sens. Saxby Chambliss of Georgia and George Voinovich of Ohio, who joined four colleagues in sending a letter to the EPA.

The senators said a tighter anti-pollution rule "could trigger layoffs nationwide, further eroding U.S. economic competitiveness, and place upward pressures on consumer inflation, further diminishing the standard of living enjoyed by the majority of our citizens."

Texas Gov. Rick Perry joined 10 other GOP governors in telling the EPA that "the scientific research on this issue does not provide compelling evidence of any health benefits" from tougher anti-pollution regulations.

Writing separately, Georgia Gov. Sonny Perdue said states are "only now in the process of developing plans and implementing measures to implement the latest revision" of the air quality standard from 1997. A new set of rules "could be disruptive to our progress," the Georgia Republican wrote.

EPA Administrator Stephen Johnson has consistently indicated that the current air quality standard isn't sufficient. Testifying to Congress last year, he pointed to 1,700 studies of ground-level ozone, or "smog," and said they show "ozone's impacts are more significant than we previously thought" in harming health.

Communities would have to submit plans to meet any new standard, with the possibility of a loss of federal dollars for failing to comply. EPA has estimated the implementation cost at $10 billion to 22 billion a year, depending on the new ozone standard.

Industry and environmental groups said they expect the EPA to set the new standard at no more than 75 parts of ozone for every billion parts of air, which is tougher than the current 80 but not as low as 70, which was recommended by outside scientists.

Frank O'Donnell, president of Clean Air Watch, a private advocacy group, said "75 would be a step in a more positive direction but would be weaker than the unanimous recommendation of EPA's science advisers — which suggests that something other than science went into the decision making."

Keith McCoy, a policy official for the National Association of Manufacturers, last week argued the 1997 air quality standard should be left alone, because "ozone is going down."

But O'Donnell pointed out that manufacturers had "aggressively" opposed that 1997 rule, too.