Foreign Pollution Saves Phoenix from Tougher Clean Air Rules, EPA Says
Published Date: 3/23/2026
Rule
Summary
The EPA says the Phoenix-Mesa area in Arizona would have met clean air ozone standards by August 3, 2024, if it weren’t for pollution coming from outside the U.S. Because of this, the area stays classified as 'Moderate' nonattainment and won’t face stricter rules or extra costs. This means Arizona doesn’t have to submit extra plans to improve air quality for now.
Analyzed Economic Effects
4 provisions identified: 4 benefits, 0 costs, 0 mixed.
Phoenix-Mesa Avoids Stricter Reclassification
The EPA found the Phoenix-Mesa, Arizona area would have met the 2015 ozone standard (70 parts per billion) by the Moderate attainment date of August 3, 2024, but for pollution from outside the U.S. Because of that finding, the area remains a Moderate nonattainment area and will not be reclassified to a more severe category.
No New Contingency Plan Submission Required
As a result of the EPA's determination, the State of Arizona is no longer required to submit attainment and reasonable further progress (RFP) contingency measures for the Phoenix-Mesa 2015 ozone nonattainment area. The area remains subject to other Moderate-area requirements but not the contingency-measures submission obligation.
No Significant Impact on Small Businesses
The EPA certified under the Regulatory Flexibility Act that this action will not have a significant economic impact on a substantial number of small entities and that it will not impose any requirements on small entities.
Tribes Within Area Not Subject to New Costs
The EPA identified Tribal lands within the Phoenix-Mesa area (Fort McDowell Yavapai Nation; Gila River Indian Community; Salt River Pima-Maricopa Indian Community; and Tohono O'odham Nation) and stated the action has Tribal implications but will not impose substantial direct compliance costs on Tribes or preempt Tribal law.
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