The Environmental Protection Agency (EPA) has approved a request from the Montana Department of Environmental Quality to change the status of the "oxygenated fuels" program in Missoula's Carbon Monoxide Limited Maintenance Plan. Previously an active control measure, it will now be a contingency measure, meaning it will only be used if necessary to meet air quality standards. This decision was made after confirming that this change will not interfere with maintaining the required air quality levels. The rule becomes effective on February 18, 2025.
Simple Explanation
The EPA gave a thumbs up to Montana's plan to use a special kind of gasoline that helps keep the air clean in Missoula only if it's really needed, instead of all the time. They checked and said this change won't make the air worse.