The Clean Air Act: a long and winding road

1970: Congress passes the Clean Air Act, creating a framework for regulating emissions of pollutants.

1990: The Environmental Protection Agency sets the limit for how much ground-level ozone can be in the air at 120 parts per billion, or ppb, measured over a 1-hour period.

1991: Atlanta is found to be in “serious” noncompliance with that standard.

1997: The EPA enacts a new ozone standard of 84 ppb, measured over an 8-hour period. Atlanta is found to be in noncompliance with the new standard.

1998-1999: EPA sanctions and environmental lawsuits force the state to scrap dozens of highway projects and forfeit hundreds of millions of dollars in federal highway funds.

2004: Atlanta is reclassified to a “severe” non-attainment area based on its ongoing failure to meet the original 1-hour standard. This forces consumers to buy a more costly, specially formulated gasoline, requires additional controls on power plants and imposes some limits on industrial expansion.

2008: Under the Bush administration, the EPA announces that it will change the 8-hour ozone standard to 75 ppb. However, the Obama Administration almost immediately suspends implementation, saying it will seek an even tougher standard. Meanwhile, the even less stringent 1997 limit remains in effect.

2010: The EPA says it favors an 8-hour standard of between 60 and 70 ppb. Many industries, states and Republicans in Congress slam the proposal.

2011: Facing fierce opposition, the White House abandons the proposed 60-70 ppb standard and reverts to the 2008 limit of 75 ppb. Atlanta is in “marginal” noncompliance, but states have until 2015 to comply before any penalties kick in.

2013: It’s time for the EPA to consider revising the ozone standard once again. (The Clean Air Act says that should happen every five years.)

The U.S. Environmental Protection Agency announced Monday that it looks like metro Atlanta is, at long last, in compliance with 1997 smog limits.

But regional and state officials face another big hurdle, even before that determination is finalized: meeting stricter air quality guidelines enacted in 2008. Meanwhile, the EPA is set to begin weighing the possibility of yet tougher limits sometime this year.

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The proposal to re-designate the Atlanta area as in attainment of the 16-year old standard for ground-level ozone is a step forward, environmental and health advocates agree. But it also shines a light on the tricky and difficult business of achieving ever-evolving air quality index benchmarks.

“It’s like this interesting moving target,” said Brian Carr, spokesman for the Clean Air Campaign. “It might be a short lived win for the region … in the sense that the new standard has been (set).”

Ground-level ozone, commonly called smog, is formed when air pollutants from vehicles, power plants and other sources react to sunlight. Inhaling ozone can cause chest pain and congestion and worsen conditions such as asthma and emphysema.

Air quality standards established in 1997 allow for ozone levels up to 84 parts per billion, or ppb. That's 84 ozone molecules out of every billion air molecules.

Today, Atlanta’s ozone level is roughly 80 ppb. In April, the EPA classified the region as a “marginal” non-attainment area, meaning we’re close but not quite there.

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State officials have until the end of 2015 to bring the region in line with the newer standard of 75 ppb before facing penalties.

The Obama administration had asked EPA officials to consider an even stricter standard, but abandoned the idea after business groups and Republicans in Congress argued it would cost companies billions of dollars to comply and force massive layoffs.

The EPA will accept public comments on Atlanta’s reclassification for 30 days before making a final ruling. The proposed action encompasses 20 counties: Barrow, Bartow, Carroll, Cherokee, Clayton, Cobb, Coweta, DeKalb, Douglas, Fayette, Forsyth, Fulton, Gwinnett, Hall, Henry, Newton, Paulding, Rockdale, Spalding and Walton.

The move to re-designate Atlanta under the 1997 limits was requested by state officials, based on air quality data gathered from 2008 to 2010.

And that, Georgia Sierra Club director Colleen Kiernan said, is problematic, because those years were the height of the recession, with fewer drivers on the road and less demand for power. Kiernan said some levels observed in 2011 and 2012 were higher than preceding years.

“We’d argue the reductions in those years were due to other factors like the recession and the weather,” she said. “I would say it’s reasonable to expect that Atlanta air monitors will show in 2013 that we are in non-attainment of 1997 standards.”

But Janice Nolen, assistant vice president for national policy with the American Lung Association, said EPA data show that emissions continued to fall even after the level of commuting and other economic indicators picked up again.

“Overall nationwide we’re not seeing the recession as the reason why emissions are going down,” she said of her organization’s analysis of an EPA air quality study.

While that’s a spot of good news, Atlanta and many other metro areas such as Los Angeles, which has yet to meet 1987 standards, have far to go, she said. The lung association took legal action against the EPA’s 2008 standards, asserting that the 75 ppb limit is still too high. The agency recommended levels of 60 ppb, she said.

There’s some evidence that even that is too high to be considered safe, especially for children, older adults and those who work outdoors, she said.

“We don’t have a point where we can say we’re home-free,” she said.

In any case, meeting the 1997 standards validates the region’s progress, said Jac Capp, chief of the Georgia Environmental Protection Division’s Air Protection Branch.

In the 1980s, Atlanta’s ozone levels exceeded 120 parts per billion at a time when cars weren’t becoming clean enough, fast enough, to keep pace with a rapidly burgeoning population.

“Automobiles that are manufactured today are so much cleaner than they used to be,” he said.

Capp said he expects ozone levels in metro Atlanta to continue falling as technology improves and cars get progressively cleaner.

The region has already felt the consequences of failure. In the late 1990s, metro Atlanta was forced to delay some federally funded highway projects because its transportation plan failed to meet air quality requirements. That is no longer the case.

In a worst-case scenario, industries that emit lots of pollutants may be barred from relocating to or expanding in a region that falls far short of air quality limits. So economic development officials welcomed the EPA’s Monday announcement.

“Anytime that a company has wider options to consider, that’s good news,” said Alison Tyrer, spokeswoman for the Georgia Department of Economic Development.

Jane Hayse, the Atlanta Regional Commission’s division manager for transportation access and mobility, said the move means the region’s efforts are paying off.

“Years ago, air quality seemed to make the headlines every day,” Hayse said. “Now we’re doing our job, we have cleaner vehicles, and we’re able to show that the air is getting cleaner.”

Brian Gist, senior attorney for the Southern Environmental Law Center, acknowledged the region’s achievement but urged environmental officials to keep their eye on the new regulations that are likely to come down the road.

“There’s no question the air quality readings, not just over the last three years but the long-term trend show improving air quality,” he said. “But this is a process. We will have future standards that will require future work. The job isn’t done now.”

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