Regional haze

 
Colorado developed a federally required Regional Haze Plan which was first approved by the Air Quality Control Commission in January 2011 and subsequently approved on December 31, 2012 by the U.S. Environmental Protection Agency.  In 2014, a settlement was reached on Best Available Retrofit Technology control at the Craig Station that was later updated and expanded to include Nucla Station resulting in additional emissions reductions and targeted revisions to the Regional Haze Plan. The updated plan was approved by the commission on December 15, 2016 and is currently undergoing EPA review. 
 
Other regional haze sites