The Environmental Protection Agency proposed the nation's strictest-ever smog limits Thursday, a move that could put large parts of California and other states in violation of federal air quality regulations.
The EPA proposed allowing a ground-level ozone concentration of between 60 and 70 parts per billion, down from the 75-ppb standard adopted under President George W. Bush in 2008.
That means cracking down further on the emissions from cars, trucks, power plants, factories and landfills. The emissions bake in sunlight and form smog.
"All Californians should applaud the crackdown, given overwhelming scientific evidence of the lung damage and premature deaths linked to ozone," said Bonnie Holmes-Gen, a spokeswoman for the American Lung Assn. in California.
Obama administration officials and environmental groups say the new standard aligns with the level scientists say is needed to safeguard against increased respiratory diseases, particularly in children and the elderly.
Though complying with the standards could cost up to $90 billion nationwide, according to the EPA, it could also save $100 billion in health costs over time.
A 65-ppb standard -- the middle of the proposed acceptable range -- would avert 1,700 to 5,100 premature deaths nationwide in 2020 compared with the 75-ppb standard, the EPA estimates. The agency projects the stricter standard would also prevent an additional 26,000 cases of aggravated asthma compared with the Bush-era standard, and more than a million cases of missed work or school.
In California, which harbors some of the nation’s dirtiest air, an estimated 19,000 people die prematurely each year as a result of pollution from ozone and particulates. Of those, about 6,500 are in the Los Angeles area.
No urban area of California meets even the 1997 federal standard of 80 parts per billion. If states fail to meet federal standards, the government can withhold highway funding. Although such punishment is rare, "it's the hammer that drives planning at the state level," Holmes-Gen said.
Besides ratcheting up pressure on highly polluted parts of Southern California and the Central Valley, the revised standard would require several new areas to take measures to slash air pollution, including parts of the northern Sacramento Valley and the Central Coast that have been in compliance under the previous standards.
Unlike Eastern and Midwestern states, where much of the pollution comes from coal-fired power plants, three-quarters of California's ozone-forming emissions are from mobile sources such as cars, trucks, trains, ships, planes and construction equipment.
In the last three years, the state has adopted the nation's strictest rules to control pollution from diesel engines in trucks and construction equipment, which emit nitrogen oxides, a precursor to smog.
The EPA's new standard could force the state to crack down further on vehicle pollution, on refineries and power plants, and even on volatile organic compounds coming from consumer products such as hair spray. Air districts also would be likely to increase efforts to control sprawl and force more concentrated land development. Statewide, the number of car trips has been growing faster than the population.
"This is going to require us to look for new solutions," said Leo Kay, a spokesman for the California Air Resources Board. "On the ground we will be looking for where we can tighten the screws."
As for how exactly that will be done, he acknowledged, "We don't have all the answers yet."
The EPA also proposed setting a "secondary standard" to protect plants and trees from repeated smog exposure during growing season, a move environmentalists said would help national parks, forests and sensitive ecosystems. Trees and other vegetation absorb heat-trapping carbon dioxide from the atmosphere, making them an important check against global warming.
In announcing the proposals, EPA Administrator Lisa Jackson said the agency was "stepping up to protect Americans from one of the most persistent and widespread pollutants we face. . . . Using the best science to strengthen these standards is a long-overdue action that will help millions of Americans breathe easier and live healthier."
Environmentalists praised the agency for proposing regulations that match the unanimous recommendations of an EPA science advisory committee.
"We applaud EPA for listening to health professionals and scientists and proposing a rule that provides real protection for millions of people," said Bruce Nilles, director of the Sierra Club's Beyond Coal campaign, adding, "This rule will help ensure that all major sources of pollution get cleaned up."
Industry groups warned that the regulations would increase business costs.
The new standard "lacks scientific justification," the American Petroleum Institute charged, calling it "an obvious politicization of the air-quality-standard-setting process that could mean unnecessary energy cost increases, job losses and less domestic oil and natural gas development and energy security."
The proposal now enters a public comment phase, which will include open hearings next month in Arlington, Va., Houston and Sacramento before the EPA makes its final decision.