• Air Toxics
• CMAQ
• Conformity

• Laws and Regulations
• Policy and Guidance
• Research
  • General Practice
  • Air Quality Planning and SIPs
  • Emissions Analysis
  • Land Use
  • Multi-Jurisdictional (Complex) Areas
  • Project Level Conformity
  • Small Urban and Rural Areas
  • Tools & Methodologies
  • Transportation Control Measures
• Reference Material
• Models & Methodologies
• Training

General Practice

The documents included below are research efforts related to the interaction of air quality and transportation practices in general.

• Transportation Conformity Domestic Scan Report: Use of Latest Planning Assumptions and Transition to MOBILE6 (October 2003) - The FHWA transportaion conformity domestic scan was initiated to identify good practices among a select number of nonattainment and maintenance areas for meeting the transportation conformity requirements of the Clean Air Act. This project was targeted at identifying and sharing good practices in meeting the latest planning assumptions of the transportation conformity process. The study also highlighted areas' efforts to address data issues associated with the transition to EPA's most recent vehicle emissions model, MOBILE6. The scan team visited six sites in the eastern and southeastern part of the country and met with key transportation and air quality officials at each location.
• Environmental Protection: Federal Planning Requirements for Transportation and Air Quality Protection Could Potentially Be More Efficient and Better Linked (April 2003) - This report documents the GAO's review of areas that have failed to demonstrate conformity and related conformity issues. The GAO reviewed all available data from EPA and DOT and conducted a Web-based survey of all MPOs and state air quality agencies. The GAO makes two recommendations that the relevant Federal agencies consider extending the 3-year time frame between required transportation plan updates and asking Congress to amend the Clean Air Act to change the conformity requirements to match, and to assess the advantages and disadvantages of statutorily requiring that the emissions budgets in air quality plans be regularly updated with new travel data and emissions models.
• Exhausting Options: Assessing SIP-Conformity Interactions (April 2003) - Prepared by Resources for the Future, Harvard University, and Sarah Siwek & Associates, this report evaluates SIP and transportation conformity interactions based on six case studies: Baltimore, MD; Houston, TX; Paducah, KY; Portland, OR; Sacramento, CA; and Washington, DC
• Linking Transportation and Air Quality Planning: Implementation of the Transportation Conformity Regulations in 15 Nonattainment Areas (March 1999) - Prepared by the Taubman Center for State and Local Government (Harvard University) for EPA and FHWA, this report documents the Conformity Assessment Project, which studied the implementation of the transportation conformity regulation in 15 nonattainment areas.

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