EPA Backs Delaware PM2.5 Air Quality Maintenance Plan
Published Date: 7/2/2026
Rule
Summary
The EPA just gave a thumbs-up to Delaware’s plan to keep the air clean in New Castle County, part of the Philadelphia area, for another 10 years. This plan focuses on controlling tiny pollution particles called PM2.5 to meet health standards. Starting August 3, 2026, this approval helps ensure cleaner air without extra costs or delays for local transportation projects.
Analyzed Economic Effects
3 provisions identified: 3 benefits, 0 costs, 0 mixed.
Delaware PM2.5 Plan Approved Through 2034
If you live in New Castle County, Delaware, the EPA approved Delaware’s second 10-year plan to maintain the 2006 24-hour PM2.5 standard through 2034. The rule is effective August 3, 2026, and the 2006 24-hour PM2.5 national standard referenced is 35 µg/m3.
No Added Delays for Local Transport Projects
Starting August 3, 2026, the EPA found Delaware’s LMP adequate for transportation conformity, which means local transportation projects in the New Castle County portion of the Philadelphia area should not face extra conformity-related costs or delays tied to the PM2.5 standard. The EPA concluded it would be unreasonable to expect motor vehicle emissions growth that would cause a PM2.5 violation.
No New Federal Burdens From Approval
The EPA states this approval does not add federal regulatory requirements beyond State law, does not impose an information-collection burden under the Paperwork Reduction Act, and does not create unfunded Federal mandates or have a significant economic impact on a substantial number of small entities. The approval action is effective August 3, 2026.
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