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

**Action Urgency Score:** 30/100

| Field | Value |
|---|---|
| Agency | Environmental Protection Agency |
| Type | Final rule |
| Action | Final rule. |
| Published | 2026-08-13 |
| Effective | 2026-09-14 |
| Significant | No |
| CFR parts | 40 CFR 52 |
| Summary | The Environmental Protection Agency (EPA) is finalizing our determination 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 determination is based on ambient air quality monitoring data from 2023 through 2025. We are also finalizing a clean data determination (CDD) based on the 2023 through 2025 data and our evaluation of preliminary air quality monitoring data from 2026. |
| Document number | 2026-16510 |

## Why this score
- Final rule.

Source: Federal Register API (Office of the Federal Register) (https://www.federalregister.gov/documents/2026/08/13/2026-16510/determination-of-attainment-by-the-attainment-date-and-clean-data-determination-for-the-2012-annual). Last refreshed: 2026-11-03T19:10:06.902Z.
Data from the Federal Register API; the published Federal Register document is authoritative. Informational only, not legal advice.