Utah’s poor air quality under spotlight again

Salt Lake City • A coalition of environmental groups filed a notice of intent to sue on Thursday, warning the U.S. Environmental Protection Agency it must hold Utah and Arizona accountable for missing deadlines to submit plans to clean up air pollution.The announcement came just as a new layer of dirty air settled in over Salt Lake City in the latest winter inversion, a phenomenon in Utah's urban corridor caused by weather and geography.The groups, led by the Center for Biological Diversity