Scientists and regulators expect that a proposed standard for measuring ground-level ozone pollution in the United States will triple the number of "non-attainment areas" - places that can't meet the grade. But new research published last week in the journal Science comes up with a startling conclusion: Nearly half of all rural locales in the eastern half of the United States could also be out of compliance with the standard.
The finding, led by atmospheric scientist William L. Chameides of the Georgia Institute of Technology, raises a series of far-reaching practical policy questions. The biggest: How to contain pollution in areas that aren't really generating too much bad air on their own.
"Pollution in rural areas is caused by a complicated combination of distant urban emissions and local and distant rural emissions," Chameides said in a statement, "so you need to come up with a regional strategy to address rural air pollution. Not only will this change the politics of how we address air pollution in the United States, but it will also probably affect the economics of air pollution control."
The current US Environmental Protection Agency threshold for ozone pollution is 0.12 parts per million measured over one hour at a given location. The proposed standard, suggested in the wake of recent studies of the health effects of ozone, would lower the threshold to 0.08 parts per million measured over eight hours. Under complex enforcement rules, areas would be declared out of compliance with the standard if the third-highest eight-hour ozone average in a three-year period exceeded the threshold.
Chameides and colleagues from Georgia Tech and North Carolina State University analyzed 1995 data for 85 rural stations, and found that 41 would have exceeded the new threshold. Only six of the 85 stations were out of compliance with the current standard.
