Illinois Haze Plan Gets EPA Nod
Published Date: 2/27/2026
Proposed Rule
Summary
The EPA is proposing to approve Illinois’ updated plan to reduce air pollution that causes haze and smog, helping protect clean air and clear skies in national parks and nearby states. This plan updates rules for fine particles and ozone pollution, making sure Illinois doesn’t mess with other states’ air quality. People and businesses in Illinois should get ready for these changes, with public comments open until March 30, 2026.
Analyzed Economic Effects
3 provisions identified: 3 benefits, 0 costs, 0 mixed.
Illinois Regional Haze SIP Proposed Approval
The EPA is proposing to approve Illinois’ Regional Haze State Implementation Plan (SIP) revision that Illinois submitted on June 3, 2024, as meeting Clean Air Act requirements for the second implementation period that runs through 2028. This action is intended to reduce air pollution that causes haze and smog and help protect clear skies in nearby national parks and downwind States.
Interstate Visibility Transport Approval
The EPA proposes to approve portions of Illinois’ infrastructure SIP submissions dated September 29, 2017 (for the 2012 PM2.5 NAAQS) and May 16, 2019 (for the 2015 ozone NAAQS) as meeting the Clean Air Act requirement to prohibit emissions that would interfere with visibility protection measures in other States' SIPs. If approved, Illinois’ SIP is being found to contain the required provisions that address interstate visibility transport.
Visibility Protection for 16 Class I Areas
Illinois EPA identified 16 mandatory Class I Federal areas that emissions from Illinois may affect, including Great Smoky Mountains National Park and Voyageurs National Park. The EPA’s proposed action notes that 2028 visibility projections for these areas (the second implementation period) are projected to be below the applicable uniform rate of progress glidepaths, supporting the proposed approval of Illinois’ plan.
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Key Dates
Department and Agencies
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