LANDER, Wyo. — Federal regulators notified Wyoming that the Upper Green River Basin did not meet federal air quality standards between 2008 and 2011 due to high amounts of ground-level ozone — a condition resulting from gas industry emissions combined with bright sunshine and snow on the ground.
The basin in western Wyoming is home to some of the nation's most intensive gas development in the Pinedale Anticline and Jonah gas fields.
In the long-awaited notice, the U.S. Environmental Protection Agency designated the area as "marginal nonattainment," the lowest of five ratings for air pollution severity, said Steven Dietrich, air quality administrator for the Wyoming Department of Environmental Quality.
It was the first time Wyoming has received that status regarding ozone, the Casper Star-Tribune reported Friday (http://bit.ly/J6RB6v).
The designation was long anticipated, however. Gov. Dave Freudenthal requested the evaluation more than three years ago to help address the pollution problem.
The national standard for ozone is 75 parts per billion over an eight-hour period. Average readings in the Upper Green River Basin, including Sublette County and parts of Lincoln and Sweetwater counties, have exceeded that slightly, Dietrich said.
Steven Dietrich, air quality administrator for the Wyoming Department of Environment al Quality, says EPA designated the area as marginal nonattainment, the lowest of five categories for air pollution severity.
"We don't believe that public health and the quality of life in our communities need to be traded away for economic activity," Mary Lynn Worl, with the group Citizens United for Responsible Energy Development, said in a release.
Ground-level ozone levels on some days during the winter in 2011 surpassed those in major U.S. cities during the summer. Such high levels did not occur this winter, which was mild and had relatively few days of conditions conducive to ozone formation.
Dietrich said energy companies have been working to lower emissions voluntarily.
"We strive to lead by example, implementing technologies that often exceed the strictest government requirements," Randy Teeuwen, spokesman for Calgary-based Encana, said in an email.
Encana is the largest operator in the Jonah Field.
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Information from: Casper (Wyo.) Star-Tribune, http://www.trib.com