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Office of Planning, Environment, & Realty (HEP)

Title 23 and 49 USC and Planning Regulations

The transportation planning provisions of Title 23 and Title 49 of United States Code (23 USC Sections 134 and 135; 49 USC Sections 5303-5306), and the air quality provisions of the Clean Air Act as amended (42 USC Sections 7401-7671q) establish the major connection between transportation planning and emission reductions from transportation sources. Regulations governing transportation conformity are found in Title 40 of the Code of Federal Regulations (40 CFR Parts 51 and 93), and are closely linked with the joint FHWA/FTA transportation planning regulations found in 23 CFR Part 450.

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Updated: 8/29/2013
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