An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Renewable Fuel Standard Program

Anti-Backsliding Determination and Study

On this page:

Rule Summary

Clean Air Act Section 211(v) requires EPA to complete an “anti-backsliding study” to determine whether the renewable fuel volumes required in the Act adversely impact air quality as a result of changes in vehicle and engine emissions. After considering the results of the study, EPA is required to either (1) promulgate fuel regulations to implement appropriate measures to mitigate, to the greatest extent achievable, any adverse impacts on air quality; or (2) determine that no such measures are necessary.

On May 29, 2020, EPA proposed that no additional measures are necessary pursuant to Clean Air Act (CAA) section 211(v) to mitigate the adverse air quality impacts of the renewable fuel volumes required under CAA section 211(o). EPA is proposing to determine that no additional fuel control measures are necessary because since 2017, EPA has been implementing the Tier 3 Motor Vehicle Emissions and Fuel Standards which are more stringent and reduce concentrations of ozone, PM2.5, NO2, and air toxics now and in the future.  In making this determination, EPA considered the analyses performed for the Tier 3 rulemaking, as well as the anti-backsliding study.

EPA is providing an opportunity for the public to comment on this proposed determination. EPA is opening a 30-day comment period on the proposed determination and will take all comments into account in developing next steps. The comment period closes on July 8, 2020.

To submit comments, identified by Docket ID No. EPA-HQ-OAR-2020-0240, go to http://www.regulations.gov. Follow the online instructions for submitting comments.

Additional Resources