Ethanol, Reformulated Gasoline


Maine Law repealed the requirement to sell only reformulated gasoline (RFG) in the Southern Maine area of York, Cumberland, Sagadahoc, Androscoggin, Kennebec, Knox and Lincoln Counties as of November 1, 2020. In order to opt-out of the federal RFG program, Maine was required to petition U.S. EPA and submit a State Implementation Plan (SIP) revision. Maine DEP's technical analysis demonstrated that emissions in these counties will continue to decline after the requirement is lifted. EPA has approved Maine's petition and determined that the removal of the federal RFG program for the Southern Maine Area is consistent with the applicable provisions of the Clean Air Act (CAA) and EPA's regulations. As a result, RFG will no longer be required in the Southern Maine Area as of September 30, 2021.

No E15 Waiver

In an effort to minimize fuel supply disruptions, on May 1, 2022, the U. S. Environmental Protection Agency (EPA) issued a waiver of federal Clean Air Act requirements allowing the sale of gasoline blends containing up to 15 percent ethanol (commonly known as E15) during the summer months. The waiver was necessary because the Clean Air Act and the implementing regulations at 40 C.F.R. Part 1090 require the use of low volatility gasoline from May 1 to September 15 in order to limit the formulation of ozone pollution. EPA’s waiver allows the sale of ethanol fuel blends of gasoline that exceed the applicable Reid Vapor Pressure (RVP) standard by up to 1 psi. However, this waiver to sell E15 does not apply in Maine since Maine has a federally approved regulation that limits the RVP during summer months and does not allow for the 1.0 psi waiver.


Ethanol is an alcohol-based fuel made by fermenting and distilling the simple sugars found in agricultural crops and wood fibers. Ethanol is blended with gasoline when used as a motor fuel. Due to its chemical properties (particularly its affinity for water), ethanol cannot be blended into the gasoline at the refinery and shipped by pipeline. It must be shipped separately by barge, rail or truck, stored separately, and then blended with gasoline at the terminal.

Nearly all gasoline distributed in Maine is blended with 10% ethanol. The introduction of ethanol in gasoline is not a state requirement. For more information, see our FAQs and the history behind the increase in blended gasoline.

Below are several documents and links about ethanol and its use:

  • Frequently Asked Questions about ethanol.
  • Fact Sheet for Storage Tank Owners Information for station owners on converting their station to ethanol-blended gasoline.
  • Ethanol Fuel & Your Boat (PDF) A brochure for boaters explaining what problems boaters might experience when running E10 gasoline.
  • List of Ethanol Free Gas Stations in Maine
  • Special Airworthiness Information Bulletin (SAIB) - This Special Airworthiness Information Bulletin (SAIB) alerts you of an airworthiness concern where you could have alcohol (ethanol or methanol) present in the automobile gasoline on any General Aviation airplane type certificated (TC) to use automobile gasoline or with automobile gasoline supplemental type certificates (STCs).
  • Converting to Ethanol (PDF file) This document created by Central Illinois Manufacturing Co. offers information for the conversion of retail service station tanks to ethanol-blended gasoline. Note: Mention of any trade names does not imply endorsement by DEP.
  • FAME Finance Authority of Maine website describing low-interest, fixed-rate financing for the removal, disposal and replacement of aboveground and underground commercial storage tanks, piping and related equipment associated with the tank, as well as the purchase and installation of vapor recovery systems.
  • EPA Renewable Fuel Standard Program: This page also contains notices, regulations and analyses regarding the Renewable Fuel Standard.
  • American Coalition for Ethanol
  • DOE Alt Fuels Department of Energy's Alternative Fuels and Advanced Vehicles Data Center.


Ethanol is available in the Maine market for several different reasons. Those reasons include federal regulatory changes and current fuel market forces.

Maine also provides tax incentives for the manufacturing and distributing of biofuels.

Federal Energy Policy Acts

EPACT 2005. The Energy Policy Act of 2005 (EPACT 2005) removed the federal Clean Air Act mandate requiring 2% oxygen in RFG as of May 5, 2006. MtBE was the refiners' primary fuel oxygenate to comply with the RFG oxygen requirement. Although EPACT 2005 did not ban the use of MtBE, the elimination of the federal oxygenate requirement led to a rapid phase-out of MtBE and a significant increase in the use of ethanol. While RFG can be produced without oxygenates, the industry uses ethanol to provide performance (octane enhancement), help achieve the lower air toxics requirements of RFG, and to make up the lost volume from MtBE.

Energy Independence and Security Act 2007. The Renewable Fuel Standard (RFS) program began in 2006 pursuant to the requirements of the Energy Policy Act of 2005 (EPAct), which were codified in CAA section 211(o). The statutory requirements were subsequently amended by the Energy Independence and Security Act of 2007 (EISA). The statute sets forth annual, nationally applicable volume targets for each of the four categories of renewable fuel. It also directs EPA to modify or establish volume targets in certain circumstances. EPA must then translate the volume targets into compliance obligations, expressed as annual percentage standards, that obligated parties must meet every year.

Maine has no renewable fuel standard requirement.