Transportation Conformity Policy and Guidance
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- Guidance for the Use of Latest Planning Assumptions in Transportation Conformity Determinations - December 2008. New 1/7/09
- Court Decision on Transportation Conformity Rule, October 20, 2006
- Transportation Conformity Guidance for Qualitative Hot-Spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas - March 2006
- Interim Guidance for Implementing the Transportation Conformity Provisions in SAFETEA-LU - February 14, 2006
- Transportation Conformity Alert to FHWA Divisions on PM2.5 Project-Level Conformity - November 17, 2005
- Planning Horizons for Metropolitan Long-Range Transportation Plans - April 12, 2005
- Transportation Conformity in Complex Areas - August 2004
- Clarification of Transportation Conformity Requirements for FHWA/FTA Projects Requiring Environmental Impact Statements - May 20, 2003
- Revised FTA Procedures for a Conformity Lapse - April 9, 2003
- Guidance on the Implementation of the March 2, 1999 Court Decision - January 2, 2002
- Guidance for Qualitative Project Level "Hot-Spot" Analysis in PM10 Nonattainment and Maintenance Areas - September 12, 2001
- Information: Limited Maintenance Plans - September 7, 2001
- Program Guidance on High Occupancy Vehicle Lanes - March 28, 2001
- Transportation Conformity Alert - August 2000
- Memorandum of Understanding between DOT and EPA on Transportation Conformity - April 25, 2000
Superseded Guidance:
EPA Guidance:
- "Guidance for Developing Transportation Conformity State Implementation Plans - January 2009" and then link to http://www.epa.gov/otaq/stateresources/transconf/policy/420b09001.pdf
- "Guidance for Implementing the Clean Air Act Section 176(c)(8) Transportation Control Measure Substitution and Addition Provision - January 2009" and then link to http://www.epa.gov/otaq/stateresources/transconf/policy/420b09002.pdf
- Area Designations for the Revised 24-hour Fine Particle National Ambient Air Quality Standard. A PDF copy of this guidance can be downloaded from the EPA website.
- Conformity Information to Inform PM-2.5 Designations
- Conformity Implementation in Multi-jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality Standards. A PDF copy of this guidance can be download from the EPA website.
- Designations for the Fine Particle National Ambient Air Quality Standards. A PDF copy of this guidance for designating nonattainment areas under the PM2.5 standard can be downloaded from the EPA website.
- Diesel Retrofits: Quantifying and Using Their Benefits in SIPs and Conformity - Guidance for State and Local Air and Transportation Agencies. A PDF copy of this guidance can be downloaded from the EPA website.
- Guidance for Creating Annual On-Road Mobile Source Emission Inventories for PM2.5 Nonattainment Areas for Use in SIPs and Conformity. A PDF copy of this guidance can be downloaded from the EPA website.
- Guidance for Determining the "Attainment Years" for Transportation Conformity in New 8-Hour Ozone and PM2.5 Nonattainment Areas. A PDF copy of this guidance can be downloaded from the EPA website.
- Guidance for Quantifying and Using Emission Reductions from Best Workplaces for Commuter Programs in State Implementation Plans and Transportation Conformity Determinations. A PDF copy of this guidance can be downloaded from the EPA website.
- Guidance for Quantifying and Using Long Duration Truck Idling Emission Reductions in State Implementation Plans and Transportation Conformity. A PDF copy of this guidance can be downloaded from the EPA website.
- Guidance on Applicable Methodologies to Account for the Benefits of Infill in SIPs and Conformity Determinations. A PDF copy of this guidance can be downloaded from the EPA website.
- Guidance on Incorporating Bundled Measures in a State Implementation Plan. A PDF copy of this guidance can be downloaded from the EPA website.
- Guidance on Quantifying NOx Benefits for Cetane Improvement Programs for Use in SIPs and Transportation Conformity. A PDF copy of this guidance can be downloaded from the EPA website.
- Improving Air Quality Through Land Use Activities - January 2001. A PDF copy of this guidance can be downloaded from the EPA website.
- Official Release of the MOBILE6 Motor Vehicle Emissions Factor Model
- Official Release of EMFAC2007 Motor Vehicle Emission Factor Model for Use in the State of California
- Official Release of the MOBILE6.2 Motor Vehicle Emissions Factor Model and the December 2003 AP-42 Methods for Re-Entrained Road Dust
- Policy Guidance on the Use of MOBILE6 for SIP Development and Transportation Conformity
- Policy Guidance on Use of November 2006 Update to AP-42 for Re-entrained Road Dust for SIP Development and Transportation Conformity
- SmartWay SIP and Transportation Conformity Guidance: Accounting for NOx Reductions from Trailer Aerodynamic Kits and Low Rolling Resistance Tires. A PDF copy of this guidance can be downloaded from the EPA Website
- Technical Guidance on the Use of MOBILE6 for Emission Inventory Preparation
- Transportation Conformity and the Revised 24-hour PM2.5 Standard. A PDF copy of this guidance can be downloaded from the EPA Website