Proposed stricter smog rules could pinch Minnesota

Tighter air pollution rules proposed Wednesday by the federal Environment Protection Agency could affect Minnesota.

Right now, the state is in compliance with the federal ground-level ozone limit of 75 parts per billion. The EPA wants to lower the limit to between 65 and 70.

Ozone, also known as smog, is formed when vehicle exhaust and other emissions mix with heat and sunlight. The EPA's proposed ozone standard is aimed at reducing smog and the health risks that come with it.

"Our air quality in Minnesota is pretty good, but the standards are catching up to us now," said Frank Kohlasch, who manages the air assessment section for the Minnesota Pollution Control Agency. "So we want to continue to protect human health and protect our environment and make reductions in the types of air pollutant that form ozone."

The state's ozone levels have been fairly stable, Kohlasch added.

Minnesota's worst ozone days usually come during the summer months. The highest recorded readings occur in the Twin Cities metro area.

"Minnesota has been right on the edge of compliance and non-compliance for a decade and a half, so under any circumstances Minnesota is going to have to do things to keep our air clean and reduce pollution," said Mike Harley director of Environmental Initiative, a group promoting voluntarily efforts to reduce the state's ozone-causing pollutants.