President Donald Trump reiterated his support Tuesday for a federal regulation requiring ethanol to be blended with motor fuel—an announcement coming the same day a former ethanol critic officially began his job as head of the U.S. Environmental Protection Agency.

In a letter to the National Ethanol Conference in San Diego, the president said he understands the importance of ethanol and the Renewable Fuel Standard to the economies of many rural communities. The standard requires gasoline and other petroleum-based fuels to be blended with biofuels.

"I also know that your industry has suffered from overzealous, job-killing regulation," Trump said in the letter. "I am committed to reducing the regulatory burden on all businesses, and my team is looking forward to working with the Renewable Fuels Association, and many others, to identify and reform those regulations that impede growth, increase consumer costs, and eliminate good-paying jobs without providing sufficient environmental or public health benefit."

The ethanol mandate has come under fire from many groups in recent years, from environmentalists to food producers. Perhaps its most vocal opponent has been the oil industry, which has pushed to have the standard removed.

Trump has expressed support for keeping the RFS in the past, but his campaign promise to boost the nation's fossil fuel industries left some observers to question whether he would renege on his pledge. The president's choice for Scott Pruitt to lead the EPA worried many in the ethanol industry because Pruitt fought the standard as Oklahoma attorney general. The agency is charged with enforcing the mandate.

Trump's reassurances in his letter appear to have quelled those worries for now. In a statement to the news site Biofuels International, RFA CEO Bob Dinneen thanked the president for supporting the standard.

"The RFS has cleaned the air, reduced our dependence on foreign oil and boosted local economies," Dinneen said. "Donald Trump understands all this." http://bit.ly/2loT15B

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