On June 12, 2018, Former Administrator Pruitt issued a letter of notification (PDF) (1 pg, 966 K, June 12, 2018, About PDF) to Butamax Advanced Biofuels LLC registering isobutanol as a fuel additive for blending into gasoline at levels up to 16 volume percent.

EPA made the registration decision after all applicable Clean Air Act requirements were met and after careful review of the numerous comments received on the March 29, 2018 Federal Register Notice regarding EPA’s intent to register isobutanol under the Fuel and Fuel Additive Registration Program at 40 CFR Part 79.

• Registration approval letter
• Federal Register Notice (PDF) (4 pp, 233 K, published March 29, 2018, About PDF)
• List of Registered Gasoline Additives