State Implementation Plan (SIP) - Transportation Conformity

Section 176(c) of the Clean Air Act (CAA) states that actions of the federal government may not cause or contribute to new violations of the CAA, nor may they increase the frequency or severity of existing violations, nor delay the attainment of a standard in a nonattainment area, and all actions must conform to the state SIP's purpose of eliminating or reducing the severity and number of violations of the National Ambient Air Quality Standards (NAAQS) and achieving expeditious attainment of such standards.

The purpose of Ohio's transportation conformity SIP is to ensure that any transportation plan developed under title 23 of the U.S. code or Chapter 53 of Title 49 of the U.S. Code for implementation in the state of Ohio, conforms to Ohio's SIP and fulfills the requirements of Section 176(c) of the CAA.


Letter to U.S. EPA

Memorandum of Understanding (MOU)


Public Hearing Results

Other Communication

Proposed Rule Date and FR Notice

Final Rule Date and FR Notice

Effective Date


Aug. 20, 2014

August 2013


 See Appendix B


March 2, 2015

80 FR 11148

March 3, 2015

80 FR 11133 Direct Final

May 1, 2015



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 As a precautionary response to COVID-19, Ohio EPA is currently operating with most staff working remotely. If you are working with our staff on a current project and you know the name of the employee you are working with, email them at or call them directly. The Agency website has contact information for every district, division, and office. In order to reach us, please contact Ohio EPA’s main phone line at (614) 644-3020 or the main line for the division or office you are trying to reach.

After March 23, our district offices and Central Office will be temporarily closed and will have increasingly limited ability to receive deliveries, plans, etc. All entities are encouraged to submit plans, permit applications, etc., electronically where there are existing avenues to do so, such as the eBusiness Center (eBiz). Please refer to the list of available services on the main eBiz webpage. We encourage you to make use of all that apply, even if you have not used eBiz in the past. Plans under 25 MB can be emailed. For large plans over 25 MB, entities should work with the reviewer/division to upload via LiquidFiles. Directions for submitting docs via LiquidFiles is available on YouTube. We apologize for the inconvenience and thank you in advance for your understanding.

To report a spill or environmental emergency, contact the spill hotline (800) 282-9378 or (614) 224-0946