scope:

Overview

This Handbook is intended to assist practitioners in addressing air quality issues, including transportation conformity requirements, as part of the National Environmental Policy Act (NEPA) process for highway projects. The Handbook summarizes key requirements under NEPA and the Clean Air Act and provides advice for documenting compliance with the Clean Air Act requirements as a part of the NEPA process.

The Background Briefing section of the Handbook provides an overview of requirements and relevant terminology. Topics addressed in the Practical Tips section of the Handbook include:

■ Determining if the project is subject to transportation conformity requirements

■ Coordinating regional conformity determinations with the NEPA process

■ Conducting hot-spot analyses and making project-level conformity determinations

■ Considering mobile-source air toxics (MSAT) emissions

■ Documenting air quality analyses and determinations in the NEPA process

Please note that this Handbook provides only a general introduction to transportation conformity requirements in relation to the analyses and decisions documented in the NEPA process; it is not a manual for carrying out air quality modeling or for making transportation conformity determinations. As such, this Handbook is likely to be most useful to practitioners who are experienced in NEPA but are not air quality specialists.