EPA slaps 'Serious' ozone label on Connecticut tribal lands
Published Date: 4/23/2026
Rule
Summary
The EPA found that the Mashantucket Pequot and Mohegan tribal lands in Greater Connecticut didn’t meet the 2015 ozone air quality standards on time. Because of this, these areas are now officially labeled as 'Serious' for ozone pollution, meaning stricter rules will kick in to clean the air. This change takes effect on May 26, 2026, and could mean new efforts and costs to improve air quality.
Analyzed Economic Effects
3 provisions identified: 2 benefits, 0 costs, 1 mixed.
Tribal Areas Reclassified to 'Serious' Ozone
The EPA found the Mashantucket Pequot Tribal Nation and the Mohegan Indian Tribe portions of Greater Connecticut did not meet the 2015 ozone standards and reclassified those tribal areas to Serious nonattainment. This reclassification is final and takes effect on May 26, 2026.
No New Small-Business Burden Certified
The EPA certified under the Regulatory Flexibility Act that this final rule will not have a significant economic impact on a substantial number of small entities. The EPA also determined the action does not trigger the Unfunded Mandates Reform Act threshold of $100,000,000 and does not create new information-collection burdens under the Paperwork Reduction Act.
No Change to Tribal NNSR Permit Requirements
EPA states that for the Mashantucket Pequot and Mohegan tribal lands the New Source Review (NNSR) major source thresholds and offset requirements will not change as a result of this reclassification because those tribal lands were already subject to Serious-area requirements under a prior ozone standard. That means stationary sources on those tribal lands seeking preconstruction permits will not see different NNSR permitting requirements from this action.
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