The Trump administration raised the prospect Tuesday that it will reduce the amount of renewable fuels to be blended into the nation's fuel supply next year.
The warning came Tuesday from the Environmental Protection Agency, which sought public comment on the possibility of using executive authority in the Clean Air Act to lower requirements across a range of renewable fuels.
The news came as a blow to the renewable fuel industry and Sen. Chuck Grassley, R-Iowa.
Agriculture interests had been pushing for an increase in volumes after the administration announced preliminary figures in July, which for advanced fuels were slightly down from 2017.
"It’s outrageous that the EPA would change course and propose a reduction in renewable fuel volumes," Grassley said in a statement. "This seems like a bait-and-switch from the EPA’s prior proposal and from assurances from the President himself and Cabinet secretaries in my office prior to confirmation for their strong support of renewable fuels."
In its notice Tuesday, the EPA said biodiesel costs could go up because of the expiration last year of a federal blenders tax credit and the possibility of import duties, which it also said could limit supply.
The agency asked about the possibility of lowering targets by 315 million gallons for biomass biodiesel and 473 million gallons for advanced biofuels and total renewable volumes.
The amounts the EPA previously announced were 2.1 billion gallons for biomass biofuels, 4.24 billion gallons for advanced biofuels and 19.24 billion gallons for total renewable fuel volumes.
President Donald Trump has said he supports renewable fuels, but EPA Administrator Scott Pruitt was a critic of the mandate while he was attorney general in Oklahoma. Last month, Pruitt told Radio Iowa the market hasn't demonstrated yet that infrastructure is in place to support higher production levels.
"We’re supposed to set volume obligations that are consistent with objective criteria,” Pruitt said.
Officials in the renewable fuels industry objected to the idea that volumes would be reduced next year, saying it would hurt consumers and it wasn't warranted.
"There is no rationale for further lowering either the 2018 advanced biofuel volume requirement or the total renewable fuel volume," Renewable Fuels Association President and CEO Bob Dineen said.