Air Plan Approval; Delaware; 2006 24-Hour Fine Particulate Matter Limited Maintenance Plan for the Philadelphia Nonattainment Area

What it does

The Environmental Protection Agency (EPA) is approving a state implementation plan (SIP) revision submitted by the State of Delaware through the Delaware Department of Natural Resources and Environmental Control (DNREC). The revision pertains to the second 10-year limited maintenance plan (LMP) for the 2006 24-hour fine particulate matter (PM2.5) national ambient air quality standard (NAAQS). The LMP addresses the New Castle County portion of the Philadelphia-Wilmington, PA-NJ-DE Area. The EPA is approving the LMP because it provides for the maintenance of the 2006 24-hour PM2.5 NAAQS through the end of the second 10-year maintenance period. In addition, the EPA is finalizing the process to find the LMP adequate for transportation conformity purposes. The EPA is approving this revision to the Delaware SIP in accordance with the requirements of the Clean Air Act (CAA).

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 final rule is effective on August 3, 2026.

The agency's dates, word for word.

Check it yourself

• The document in the Federal Register
• Docket EPA-R03-OAR-2025-0205 on Regulations.gov
• Title 40 on eCFR

The record as published

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