California has the worst air.
WASHINGTON (AP) – Counties in 31 states are flunking air-quality standards, drawing a federal warning to clean up industrial plants, put new restrictions on cars and take other action to make their air less polluted.

Nearly 500 counties, mostly in California and the eastern third of the country, were cited Thursday as having too much smog-causing pollution in violation of the federal clean air law.

The Environmental Protection Agency told state and local officials to develop new pollution controls to reduce ground-level ozone, a precursor of smog. Some 159 million people, about half the U.S. population, live in areas singled out by the government for contributing to unhealthy air.

Acting under court order, the EPA identified all or parts of 474 counties that either have air that is too dirty or have pollution that causes neighboring counties to fail the air quality test.

Despite having some of the toughest air pollution requirements, California still has the worst air, the EPA said.

The Los Angeles basin was designated as having severe air pollution, the only one in the category. The area has until 2021 to come into compliance with the federal standard.

Three California regions – Riverside County, San Joaquin Valley, Sacramento – were listed with serious pollution, the fourth-worst designation, and given until 2013 to curtail the pollution.

Other areas with marginal or moderate pollution problems have until either 2007 to 2010 to comply. Areas that continue to violate the standard could lose federal highway dollars.

Those areas include a ring of Great Lakes states and a concentration of Northeast states from the Washington, D.C., area to Boston. Also failing the federal test were parts of eastern Tennessee, Georgia, North Carolina, and Dallas, Houston and San Antonio.

The EPA said regions in noncompliance may have to impose new controls on industrial plants, restrict transportation and require tougher vehicle inspection programs. Some counties may have to require the use of special, cleaner-burning gasoline.

The EPA has said it will act to reduce pollution from power plants. But in a companion regulation, the agency Thursday proposed new requirements to curtail pollution drifting from power plants and other industrial facilities. The proposal, resulting from a court order, is intended to cut haze in 156 parks and wilderness areas in 35 states.

EPA Administrator Mike Leavitt said he held dozens of private meetings with members of Congress, local officials, industry representatives and environmental and public health advocates, who argued either for or against being included in the list.

The new standards were adopted in 1997 but delayed because of court challenges. They allow less ozone in the air and requires monitoring of air quality over eight hours instead of one hour, because of concerns for children, the elderly and people with respiratory illnesses.

Leavitt said it would be unfair to say that dirty air is a national problem. “There may be a few areas where that phrase applies, but there aren’t many,” he said.

In 1991, under the older standard, the EPA designated 371 counties as having air with ozone. Some counties fixed the problem; others fell into noncompliance because of the tougher 1997 standards.

The standards were delayed from taking effect for four years because of a lengthy court challenge by industry and states. They were upheld by the Supreme Court in February 2001. Environmental and public health groups sued to force government into action.

He said 2,668 counties met the standards.