The EPA administrator, Stephen Johnson, said the proposed California rules were pre-empted by federal authority and made moot by the energy bill signed into law by President George W. Bush on Wednesday. Johnson said California had failed to make a compelling case that it needed authority to write its own standards for greenhouse gas emissions from cars and trucks to help curb global warming.
"The Bush administration is moving forward with a clear national solution, not a confusing patchwork of state rules," Johnson said in an evening conference call with reporters. "I believe this is a better approach than if individual states were to act alone."
Other states affected by the ruling included New York, New Jersey and Connecticut.
The decision immediately sparked a heated debate over its scientific basis and whether political pressure was applied by the automobile industry to help it escape the proposed California regulations. State officials and environmental groups vowed to sue to overturn the edict.
The 17 states had waited two years for the Bush administration to issue a ruling on an application to set stricter air quality standards than those adopted by the federal government. The denial of the request, technically known as a Clean Air Act waiver, is the first of more than 50 applications that the federal government has refused to allow California to set its own pollution rules.
The emissions standards California adopted in 2004 — but not been approved by the federal government — would have forced automakers to cut greenhouse gas emissions by 30 percent in new cars and light trucks by 2016, with the cutbacks to begin in 2009 models.
That would have translated into roughly 43 miles per gallon for cars and some light trucks and about 27 miles per gallon for heavier trucks and sport utility vehicles.
The new federal law will require automakers to meet a 35-mile-per-gallon fleetwide standard for cars and trucks sold in the United States by 2020. It does not address carbon dioxide emissions, but such emissions would be reduced as cars were forced to become more fuel efficient.
California's proposed rules had sought to address the impact of carbon dioxide and other pollutants from cars and trucks that scientists say contribute to the warming of the planet.
Governor Arnold Schwarzenegger of California said the states would go to federal court to reverse the EPA decision.
"It is disappointing that the federal government is standing in our way and ignoring the will of tens of millions of people across the nation," Schwarzenegger said. "We will continue to fight this battle."
He added, "California sued to compel the agency to act on our waiver, and now we will sue to overturn today's decision and allow Californians to protect our environment."
Twelve other states — New York, New Jersey, Connecticut, Maine, Maryland, Massachusetts, New Mexico, Oregon, Pennsylvania, Rhode Island, Vermont and Washington — had proposed standards like California's, and the governors of Arizona, Colorado, Florida and Utah have said they would do the same.
If the waiver had been granted and the 16 other states had adopted the California standard, it would have covered at least half of all vehicles sold in America.
Automakers praised the decision. "We commend EPA for protecting a national, 50-state program," said David McCurdy, president of the Alliance of Automobile Manufacturers. "Enchancing energy security and improving fuel economy are priorities to all automakers, but a patchwork quilt of inconsistent and competing fuel economy programs at the state level would only have created confusion, inefficiency and uncertainty for automakers and consumers."
In recent weeks, the chief executives of the Detroit auto companies were in Washington to lobby for less-stringent regulations.
Industry analysts and environmental groups said the EPA decision had the appearance of a reward to the industry, in return for dropping its opposition to the energy legislation. Auto industry leaders issued statements supporting the new energy law, which gives them more time to improve fuel economy than California would have.
State officials reacted with dismay. The California attorney general, Edmund Brown Jr., called the decision "absurd." He said it ignored a long history of waivers granted California to deal with its special topographical, climate and transportation circumstances, which require tougher standards than those set nationally. Brown noted that federal courts in California and Vermont upheld the California standards this year against challenges by the auto industry.www.iht.com