By DAN JOLING
Associated Press

ANCHORAGE, Alaska (AP) - Three Alaska groups sued Friday to demand the Environmental Protection Agency enforce the cleanup of some of the nation's most polluted winter air around the state's second-largest city.

The lawsuit filed in Seattle by environmental law firm Earthjustice says the state of Alaska has failed to submit a legally compliant plan to address the problem of particulate pollution caused by wood-burning stoves and other sources in the Fairbanks area. It urges the U.S. agency to set a deadline for a state cleanup plan and impose a federal proposal with stricter requirements if Alaska does not act within the timeframe.

"We've been waiting for over 10 years for action that results in cleaner air," Patrice Lee of Citizens for Clean Air, one of the groups suing, said in a statement.

Suzanne Skadowski, a spokeswoman for the EPA in Seattle, said she could not respond immediately to the lawsuit but that agency staff members have put a lot of time, effort and resources into helping the state and Fairbanks seek cleaner air.

The agency designated the Fairbanks North Star Borough as out of compliance with federal air standards in November 2009. The borough has more violations than any other such area nationwide, according to the lawsuit.

A major source of fine particulate around Fairbanks is woodstoves, which many residents use to warm homes instead of more expensive fuel in a region that routinely sees winter temperatures dip to minus 40 degrees.

Fine particulate is a mix of solid particles and liquid droplets that can be inhaled deep in the lungs. It can cause premature death in people with heart and lung diseases. The young and the elderly are especially susceptible.

The pollution problem also is worsened by hills surrounding Fairbanks creating a bowl effect. Particulate can be trapped by inversions, layers of warmer air that cap cold, dirty air and keep it from dissipating.

State officials have pushed for a local solution, but limits on woodstoves are controversial. Fairbanks voters in October approved a measure prohibiting local officials from regulating how people heat their homes.

Citizens for Clean Air, Alaska Community Action on Toxics and the Sierra Club have previously sued three times to demand enforcement of deadlines under federal clean air laws.

The latest lawsuit asks a judge to compel the EPA to find that Alaska has failed to submit a serious plan to address the air in Fairbanks. Federal law required the agency to make such a finding by June 30, it says.

The finding would have started the clock on a two-year deadline for the state to submit an appropriate plan or for the EPA to prepare one. A federal plan carries the threat of sanctions and additional permit requirements for new pollution sources.

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