Determination of Attainment by the Attainment Date and Clean Data Determination for the 2012 Annual Fine Particulate Standard; Plumas County, California

What it does

The Environmental Protection Agency (EPA) is proposing to determine that the Portola nonattainment area in Plumas County, California, attained the 2012 annual fine particulate matter ("PM<INF>2.5</INF>") national ambient air quality standard (NAAQS or "standard") by the December 31, 2025 "Serious" area attainment date. This proposed determination is based on ambient air quality monitoring data from 2023 through 2025. We are also proposing to make a clean data determination (CDD) based on the 2023 through 2025 data. If we finalize this CDD, certain Clean Air Act (CAA) requirements that apply to the Portola nonattainment area will be suspended for so long as the area continues to meet the 2012 annual PM<INF>2.5</INF> NAAQS. The area would remain designated nonattainment for the 2012 annual PM<INF>2.5</INF> NAAQS, unless and until the State submits, and EPA approves, a redesignation request and maintenance plan for the area. We are taking comments on this proposal and plan to follow with a final action.

The Environmental Protection Agency's summary, as published in the Federal Register.

What it would change

2 parts of Title 40 of the Code of Federal Regulations:

40 CFR 52, 40 CFR 81

What happens next and when

Comments must be received on or before June 15, 2026.

The agency's dates, word for word.

Check it yourself

• The document in the Federal Register
• Docket EPA-R09-OAR-2026-2608 on Regulations.gov
• Title 40 on eCFR

The record as published

Source: the Federal Register (public domain). The document in the Federal Register