Clean Air Act at 40 - breathing easier, but battles loom
Today marks the 40th anniversary of the passage of the Clean Air Act, a sweeping environmental law that's widely credited with helping millions of Americans breathe easier - and even saving lives - but is still the focus of fierce debates.
The Baltimore area once had such bad summertime smog that its air ranked among the nation's unhealthiest, second or third only to Los Angeles'. The air quality has improved in both places since then, with ground-level ozone pollution concentrations declining. Acid rain, once blamed for killing lakes and streams in the Northeast, has also abated.
Those gains didn't come without conflict, as industries warned they'd be ruined by requirements for now widely accepted pollution controls like putting catalytic converters on cars and scrubbers on coal-burning power plants, and removing lead from gasoline. Nationally, chronic ozone levels were 14 percent lower in 2008 than in 1990, the year Congress made its last major revision of the law. Other pollutants were down even more. (Smog, though, is heavily influenced by weather, and this summer's extreme temperatures have pushed ozone levels back up this year - though still not to the extremes seen in decades past.)
Even so, the law remains a battleground, as air-quality standards have been repeatedly tightened in response to new research indicating some segments of the population still suffer health problems from chronic exposure to lower levels of ozone and fine particulates. There's a fight now over a new move to lower ozone limits again.
The biggest struggle, though, is over the EPA's use of the Clean Air Act to regulate climate-warming greenhouse gas emissions. With climate-change legislation stalled in Congress, the Obama administration has moved ahead with moves to track and ultimately limit carbon dioxide emissions, relying on a Bush-era Supreme Court decision upholding the law's use to deal with climate change. Lawmakers, some of them representing oil and coal-producing regions, have introduced bills to block further action. arguing carbono-dioxide emission regulations would hurt the economy.
Amid tug of war in Washington over federal action, states like Maryland, meanwhile, have adopted their own laws clamping down on pollutants (Health Air Act) and are proceeding under state legislation to do the same with greenhouse gas emissions within their borders.
Clean air, as ever, is a hot topic. For more on the law, go here.
(Constellation Energy's Brandon Shores power plant, 2010 Baltimore Sun photo by Kenneth K. Lam)