Data / Federal rules / 2025-20203

Air Plan Approval; Montana: Infrastructure Requirements for the 2015 Ozone National Ambient Air Quality Standards

The Environmental Protection Agency published this final rule in the Federal Register on November 18, 2025. It took effect on December 18, 2025.

SpecStream is the live web data engine for teams and agents. It reads every rule and proposed rule in the Federal Register each morning, and this page is that reading. Name your industry once and new rules, comment deadlines and effective dates arrive in your sheet, CRM, Slack or agent as they are published.

Get new rules for your industry

What the agency says

The Environmental Protection Agency (EPA) is approving elements of a state implementation plan (SIP) submission from Montana regarding the infrastructure requirements of the Clean Air Act (CAA) for the 2015 8-hour ozone National Ambient Air Quality Standards (NAAQS). The infrastructure requirements are designed to ensure that the structural components of each state's air quality management program are adequate to meet the state's responsibilities under the CAA. Additionally, EPA is finalizing approval of Montana's request to update their SIP to incorporate the most recent version of EPA's "Guidelines on Air Quality Models." EPA is taking this action pursuant to the CAA.

Key facts

Document number: 2025-20203
Type: Final rule
Action: Final rule
Agency: Environmental Protection Agency
Published: November 18, 2025
Takes effect: December 18, 2025
Dates: This rule is effective on December 18, 2025.
Docket: EPA-R08-OAR-2019-0418; FRL-12875-02-R8
Code of Federal Regulations: 40 CFR 52
Topics: Air pollution control; Carbon monoxide; Environmental protection; Incorporation by reference; Intergovernmental relations; Lead; Nitrogen dioxide; Ozone; Particulate matter; Reporting and recordkeeping requirements; Sulfur oxides; Volatile organic compounds
Pages: 4

The document on federalregister.gov PDF

Other documents from the Environmental Protection Agency

Document	Type	Published
Virginia: Approval of State Coal Combustion Residuals Permit Program 2026-21622	Final rule	Oct 22
Utah Underground Injection Control Program; Class VI Primacy 2026-21618	Proposed rule	Oct 22
Nevada: Codification and Incorporation by Reference of Approved Underground Storage Tank Program 2026-21603	Final rule	Oct 22
New Source Performance Standards and National Emission Standards for Hazardous Air Pollutants; Delegation of Authority to Northwest Clean Air Agency, Washington State 2026-21383	Proposed rule	Oct 19
Air Quality Plan; Arizona; Agricultural Best Management Practices Rules for the West Pinal County PM10 Nonattainment Area 2026-21289	Proposed rule	Oct 19
Approval and Promulgation of Implementation Plans-Pinal County (Part); West Pinal, AZ PM10 Nonattainment Area; Moderate Area, Serious Area, and Section 189(d) Plan for Attainment of the 24-Hour PM10 Standard 2026-21288	Proposed rule	Oct 19
Air Quality Plan; Arizona; Pinal County Air Quality Control District; West Pinal County PM10 Nonattainment Area; Fugitive Dust Rules 2026-21287	Proposed rule	Oct 19
Approval and Promulgation of Implementation Plans; Arizona; Revisions to the Cleaner Burning Gasoline, Winter Oxygenated Fuel, and Gasoline Set-Aside Programs 2026-21268	Final rule	Oct 19

Everything from the Environmental Protection Agency · Rules on air pollution control · Rules on carbon monoxide · Rules on environmental protection · Published in November 2025

Read from the Federal Register API, last updated 2026-10-23. The document on federalregister.gov is the official record; dates and dockets can change through later corrections. Free to reuse with credit to SpecStream under CC BY 4.0.