The Environmental Protection Agency is expected to rule this week whether 15% ethanol-blended gasoline will now become the nation’s standard transportation fuel, but that doesn’t mean the higher E15 gas-ethanol blend will be found at the pump any time soon: even if the agency approves the switch—the agency has already asked for more time and information—refiners are saying they won’t put more ethanol into their gasoline unless Congress gives them protection from potential lawsuits from motorists or consumers who claim the ethanol hurt their engines.

Just because the agency can approve higher ethanol content, “that doesn’t mean anybody is forced to sell it,” said Charles Drevna, president of the National Petrochemical and Refiners Association. The group may not want to use E15, but they still must comply with the federal usage mandates. Refiners could do that by purchasing credits, instead of buying the actual ethanol. Liability issue isn’t the only concern for refiners. They are operating under capacity because gasoline consumption is down and adding more ethanol to their fuel means gasoline usage could fall still more.

The pro-ethanol trade group Growth Energy and 54 ethanol manufacturers petitioned the EPA last March to allow gasoline rated as standard transportation fuel to contain up to 15% ethanol by volume. The group filed the request as an emergency waiver appeal to forego the usual multi-year data gathering and research process associated with such fuel changes. According to agency rules, the appeal required a yea or nay response within six months, yet in mid November agency officials said that time frame won’t likely be met. The head of the EPA said the agency may have to work past the December 1 deadline because it is still reviewing test results on the engine effects of higher blend rates on a variety of products.