On March 15, Sens. John Thune, R-S.D.; Deb Fischer, R-Neb.; Roy Blunt, R-Mo.; Chuck Grassley, R-Iowa; and Joni Ernst, R-Iowa, sent a letter to President Donald Trump opposing proposed changes to the Renewable Fuel Standard.

“We are opposed to applying a ‘waiver cap’ mechanism of any kind to the RFS,” the senators wrote. “A waiver cap is designed to abruptly drive down the price of renewable identification numbers (RINs) by reducing the amount of biofuels produced. The proposed waiver credit would replace gallons of manufactured biofuels with paper credits. Enacting such a policy makes it impossible for you to honor your commitment of a 15 billion gallon RFS.”

The senators cite a recent study commissioned by Valero that states “a recent proposal of a [10 cent] per RIN waiver credit price would be only used for replacing RINs required beyond the blend wall.” The senators explain that the 10 cent RIN waiver is intentionally designed to limit the RFS to 10 percent ethanol blends.

“Implementing such a waiver would result in a significant reduction of higher blends of ethanol like E15 and E85, as well as biodiesel,” the senators wrote. “In many areas, those fuels would be eliminated from the marketplace. Let there be no doubt—the consequences of a waiver would be severe and immediate across the Midwest, impacting farmers and biofuel stakeholders alike.”

The senators stress that there are a number of options available to reduce RIN prices without intentionally undermining the RFS, including a Reid vapor pressure (RVP) waiver for E15 that would allow the fuel to be sold year-round.

Within the letter, the senators request a meeting with Trump to discuss the harm a RIN waiver cap would cause to the American agriculture sector and to offer constructive solutions to lower the price of RINs.