Montana's Sky-Clearing Plan Gets EPA Nod for Haze and Ozone
Published Date: 9/11/2025
Proposed Rule
Summary
The EPA is giving a thumbs-up to Montana’s updated plan to clear up the skies and keep them that way for the next few years. This plan helps protect special natural areas from pollution that makes the air hazy, especially from ozone. Montana’s plan kicks in soon and aims to keep our air cleaner without costing extra money for businesses or people.
Analyzed Economic Effects
2 provisions identified: 2 benefits, 0 costs, 0 mixed.
Montana regional haze SIP approval
If you live in Montana, the EPA is proposing to approve Montana’s regional haze State Implementation Plan (SIP) that the State submitted on August 10, 2022. The plan revises long-term strategies for the second implementation period to make reasonable progress toward preventing and remedying human-caused visibility impairment in mandatory Class I Federal areas (special natural areas), and the EPA says the plan aims to keep the air cleaner without costing extra money for businesses or people.
Prong 4 approval for 2015 ozone NAAQS
If you live in Montana, the EPA is proposing to approve the prong 4 (visibility) portion of Montana’s October 1, 2018 Infrastructure SIP for the 2015 8-hour ozone National Ambient Air Quality Standard (NAAQS). This action addresses visibility-related requirements tied to the 2015 ozone NAAQS.
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