# Air Plan Disapproval; Colorado; Regional Haze Plan for the Second Implementation Period
> **Rule** · Final rule. · Published 2026-01-26 · Effective 2026-02-25 · 91 FR 3048
## Document
- **Document number:** 2026-01413
- **Category:** air-emissions
- **Federal Register citation:** 91 FR 3048
- **CFR reference:** 40 CFR 52
- **Publication date:** 2026-01-26
- **Effective date:** 2026-02-25
- **State:** CO
- **EPA docket:** EPA-R08-OAR-2024-0607
## Abstract

The Environmental Protection Agency (EPA) is disapproving a regional haze state implementation plan (SIP) revision submitted in 2022 by the State of Colorado under the Clean Air Act (CAA or Act) and the EPA's Regional Haze Rule (RHR) for the program's second implementation period. Colorado's 2022 regional haze SIP revision addresses the requirement that states revise their long-term strategies every implementation period to make reasonable progress towards the national goal of preventing any future, and remedying any existing, anthropogenic impairment of visibility, including regional haze, in mandatory Class I Federal areas (Class I areas). We are disapproving Colorado's 2022 regional haze SIP revision pursuant to the CAA and regulatory regional haze requirements. The EPA is not taking final action at this time on a separate revision to Colorado's SIP that consolidates existing, previously approved regional haze provisions into the same regulation where Colorado's new, second planning period provisions are located.

## Source
- [Federal Register document](https://www.federalregister.gov/documents/2026/01/26/2026-01413/air-plan-disapproval-colorado-regional-haze-plan-for-the-second-implementation-period)
---
*AI Analytics · CC0 1.0*