Conditional Approval; Contingency Measure State Implementation Plan for the 2008 Ozone Standards; San Joaquin Valley, California

What it does

The Environmental Protection Agency (EPA) is taking final action to conditionally approve a state implementation plan (SIP) submission under the Clean Air Act (CAA or "Act") that addresses the contingency measure requirements for the 2008 ozone national ambient air quality standards (NAAQS or "standards") for the San Joaquin Valley ozone nonattainment area. The SIP submission, titled the "Ozone Contingency Measure State Implementation Plan Revision for the 2008 and 2015 8-hour Ozone Standards" ("2024 SJV Ozone Contingency Measure Plan," "Contingency Measure Plan," or "Plan") relies on two ozone contingency measures that the EPA has already approved in separate rulemakings. The approval is conditional because it relies on commitments by the State air agency and regional air district to supplement the 2024 SJV Ozone Contingency Measure Plan with submission of specific additional contingency measures within one year of the EPA's final conditional approval. The EPA is taking final conditional approval action of the SIP submission because the Agency has determined that the existing approved contingency measures, the commitments to submit additional contingency measures, and the justification for not adopting contingency measures that would achieve the recommended amount for such measures, meet the applicable requirements for such SIP submissions for the San Joaquin Valley for the 2008 ozone NAAQS. This conditional approval adds the 2024 SJV Ozone Contingency Measure Plan to the federally enforceable California SIP.

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

What changed in the regulation

1 part of Title 40 of the Code of Federal Regulations:

40 CFR 52

Wording on eCFR: the day before it took effect and from the day it took effect (first part listed).

Compared with

The Environmental Protection Agency has published 243 final rules in 2026 so far, compared with 263 in all of 2025.

Counted by the Tribune from Federal Register records since Jan. 1, 2025.

What happens next and when

This rule is effective July 6, 2026.

The agency's dates, word for word.

Check it yourself

• The document in the Federal Register
• Docket EPA-R09-OAR-2024-0338 on Regulations.gov
• Title 40 on eCFR

The record as published

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