Cheyenne, WY – The state Department of Environmental Quality has not issued any more ozone advisories for southwest Wyoming.
The agency had issued ozone advisories for the past two days for the Upper Green River Basin in Sublette County. That was based on predicted weather patterns that might be conducive to creating the air pollutant.
But ozone levels on Wednesday appeared to stay below levels that could have caused respiratory problems in people. And levels have not exceeded unsafe levels so far on today/Thursday.
Based on the advisories, oil and gas companies reduced some operations to help control truck emissions, but did not stop drilling operations.
Officials say the ozone is caused by pollution emitted from natural gas fields in southwest Wyoming and a mix of calm weather, snow cover and strong temperature inversions.