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  2. Fuels Registration, Reporting, and Compliance Help

A company wishes to blend RFG containing ethanol with RFG containing an ether, such as MTBE. May this blending occur during the VOC-controlled season? During the non-VOC-controlled season?

See More Frequent Questions about Fuels Registration, Reporting, and Compliance Help.

Under § 80.78(a)(8), and as explained in the answer to Prohibitions Question 1 in the September 26, 1994 Question and Answer Document, RFG may not contain a mixture of ethanol and any other oxygenate during the VOC control season (June 1 through September 15 at the retail level). This precludes mixing ethanol-based RFG with RFG containing other oxygenate during the VOC control season and during the period retail tanks are being blended to meet the VOC control standards in advance of June 1. In fact, § 80.78(a)(8) prohibits mixing VOC controlled RFG containing ethanol with any VOC controlled RFG containing any other oxygenate between January 1 and September 15.

All gasoline, including RFG, is subject to the substantially similar requirements, which prohibits gasoline from containing mixtures of ethanol and other oxygenates where the total oxygen content is greater than 2.7 weight %. The substantially similar restriction (unlike the § 80.78(a)(8) prohibition) is not violated at the retail level, however, if an impermissible mixture results from deliveries to the retail outlet of different gasolines each containing legal types and amounts of oxygenate. (10/17/94)

This question and answer was posted at Consolidated List of Reformulated Gasoline and Anti-Dumping Questions and Answers: July 1, 1994 through November 10, 1997 (pdf) (333 pp, 18.17 MB, EPA420-R-03-009, July 2003)

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Last updated on May 20, 2025
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