WASHINGTON (USA TODAY) -- The question was who should pay for air pollution that crosses state lines. The answer, the Supreme Court ruled Tuesday, is blowing in the wind.
States in the Midwest and South whose polluted air flows north and east must comply with a federally-imposed solution, a 6-2 majority of justices ruled.
The decision was a boon for the Obama administration and its environmental regulators, who have proposed a rule requiring some 28 upwind states to slash ozone and fine particle emissions by varying amounts because of their downwind effects. Most of those states have rebelled against the one-size-fits-all solution.
The case focuses on air currents miles overhead but has down-to-earth consequences. The EPA blames exposure to ozone and fine particles in the air for one in 20 deaths in the United States, 90,000 hospital admissions, 200,000 non-fatal heart attacks and 2.5 million cases of aggravated asthma.
Attorneys for the objecting states and industries argued that the EPA was imposing a solution on the states before they could devise their own emissions control plans. As a result, Texas solicitor general Jonathan Mitchell said during oral arguments in December, "they have to overshoot and over-control and over-regulate."
It's known as the "good neighbor" provision, but the neighbors aren't playing nice. Twenty-four states urged the justices to uphold a federal appeals court ruling striking down the EPA rule. Nine states and six cities asked them to reverse the appeals court decision and reinstate the rule.
The high court first dealt with the issue in 1907, when Justice Oliver Wendell Holmes ruled against two copper smelters in Tennessee for the "wholesale destruction of forests, orchards and crops" in Georgia. In 1963, Congress passed the Clean Air Act, the nation's most powerful tool against air pollution, and has updated it several times since.
The cross-state transport rule was born in 1977 and tightened in 1990, but federal regulators never have been able to make it work. The latest effort sets tough standards for "upwind" states and their polluting industries, mostly coal- and oil-fired power plants.
A three-judge panel of the U.S. Court of Appeals for the D.C. Circuit struck down the rule last year, ruling that EPA didn't give states enough time to devise their own emissions reduction plans. It also said the agency did not limit the fix to each state's "significant contribution" to the overall problem.
But the court's majority ruled that with air pollution blowing in the wind, it would be nearly impossible to apportion blame precisely, making a federal solution based on costs and other factors more palatable.
The justices also noted that mid-Atlantic and Northeast states cannot meet federal emissions control standards without help from their neighbors to the west and south. Maryland, which spent $2.6 billion on its own emissions control efforts between 2007-10, estimates that 70% of its air pollution floats in over its borders.
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