Ozone Nonattainment Information
CAUTION: SOME FILES MAY BE IN EXCESS OF 5 MB
The State of Wyoming has one ozone nonattainment area located in the Upper Green River Basin (UGRB) which includes Sublette County and portions of Lincoln and Sweetwater Counties. This area was classified as a "marginal" nonattainment area by the Environmental Protection Agency (EPA) effective July 20, 2012. A nonattainment area is one in which air quality does not meet the ozone standards set forth by the Federal government in 2008, which is 75 parts per billion over an eight-hour period.