Arizona's Pollution Plan Gets EPA Thumbs-Up (Maybe)
Published Date: 10/23/2025
Proposed Rule
Summary
The EPA is proposing to approve Arizona’s plan to control air pollution that could harm air quality in other states, focusing on tiny particles called PM2.5 from 2012 standards. This means Arizona must keep its pollution in check so it doesn’t cause problems beyond its borders. People and businesses in Arizona should note that comments on this plan are open until November 24, 2025, with no new costs announced yet.
Analyzed Economic Effects
2 provisions identified: 2 benefits, 0 costs, 0 mixed.
Arizona sources avoid new PM2.5 cuts
If you run a business or source in Arizona that emits fine particulate pollution (PM2.5), the EPA proposes to approve Arizona’s plan for the 2012 PM2.5 standard. The EPA found Arizona is not “linked” to any out-of-state monitors and says the State is not required to perform the last two steps (steps 3 and 4) of the four-step interstate transport framework, so this proposed action does not add new federal interstate-control requirements beyond state law.
Tribal lands excluded from SIP approval
This proposed approval of Arizona’s SIP does not apply on any Indian reservation land or in areas where an Indian Tribe has demonstrated jurisdiction. In Indian country, the rule is not approved to apply and the EPA says it will not impose substantial direct costs on Tribal governments or preempt Tribal law.
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Key Dates
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