The Environmental Protection Agency proposed the nation's strictest-ever smog limits Thursday, a move that could put large parts of the country in violation of federal air-quality regulations.
The EPA proposed allowing a ground-level ozone concentration of 60 to 70 parts per billion, down from the 75 parts per billion standard adopted under President George W. Bush in 2008.
Obama administration officials and environmental groups say the new standards align with the levels scientists say are needed to safeguard against increased respiratory diseases, particularly in children, and that they could eventually save $100 billion in heath costs. The EPA said compliance costs could be up to $90 billion nationwide.
The EPA's proposal could lead to cleaner air in Maryland, where the Baltimore area once was considered second to Los Angeles as the smoggiest place in the country. Though air quality has improved greatly in recent years as a result of pollution controls imposed at the federal and state level, it is still worse in most of the state than what the EPA is considering as the new safety threshold for human health.
But it is likely to lead to new pollution limits on power plants and government mandates to make fuels and motor vehicles even cleaner, which could raise their costs.
State officials and environmentalists welcomed the move.
"It means cleaner air and better health throughout Maryland and other states," said Frank O'Donnell of Clean Air Watch, a Washington group.
"It's the right thing for public health," said Dawn Stoltzfus, spokeswoman for the Maryland Department of the Environment. But she said much of the pollution fouling Maryland's air comes from out of state, so state officials hope the EPA will act to regulate emissions that cross state lines. The Supreme Court overturned an earlier EPA rule governing interstate air pollution.
A 65-ppb standard - the middle of the proposed range - would avert 1,700 to 5,100 premature deaths nationwide in 2020, compared with the 75-ppb standard, the EPA estimates. The agency says the stricter standard would prevent 26,000 more cases of aggravated asthma and more than 1 million days when people miss work or school.
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 boost national parks, forests and sensitive ecosystems.
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. "This rule will help ensure that all major sources of pollution get cleaned up."
Industry groups warned that the stricter regulations would increase business costs.
The American Petroleum Institute said the proposal "lacks scientific justification" and that "there is absolutely no basis for EPA to propose changing the ozone standards promulgated by the EPA Administrator in 2008. To do so is 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 process, which will include hearings next month in Arlington, Va.; Houston and Sacramento, Calif., before the EPA makes a final decision.
Maryland counties over suggested limit
Maryland counties where ozone levels were higher from 2006-2008 than the range of limits under consideration by the EPA:
* Anne Arundel
* Baltimore
* Calvert
* Carroll
* Cecil
* Charles
* Frederick
* Garrett
* Harford
* Kent
* Montgomery
* Prince George's
* Washington
Baltimore City's ozone levels exceeded the lower limit the EPA is considering, of 60 parts per billion, but were just under the higher limit of 70 parts per billion.