In a process that began under the LePage Administration, and then continued after revisions from the Mills Administration, the Environmental Protection Agency (EPA) has finally granted a petition from the Maine Department of Environmental Protection (DEP) to remove a majority of Maine from the Ozone Transport Region (OTR), effective March 10, 2022.

The EPA approved Maine DEP’s petition after reviewing evidence that Maine has maintained continued attainment with Ozone National Ambient Air Quality Standards (NAAQS) and that further control will not significantly impact the attainment of the Ozone Standard in other parts of the OTR.

As a result, most of the state of Maine will be removed from the OTR, a designation meaning that Maine was treated as if it were in nonattainment with ozone standards, even though it was actually in compliance. Under the petition, a portion of the state, specifically, towns located in the Mid-Coast and Greater Portland regions, will remain in the OTR.

In the portions of Maine no longer in the OTR, new major sources and major modifications at existing sources will no longer need to meet the most stringent Lowest Achievable Emission Rate (LAER) standard, or obtain potentially extensive and scarce offsets, thus opening the door to potential economic growth in those areas.