US lawmakers urge EPA to finalize stronger biodiesel proposal to aid soy farmers

A bipartisan group of 47 federal lawmakers asked US Environmental Protection Agency (EPA) Administrator Lee Zeldin to maintain the stronger renewable volume obligations for biomass-based diesel proposed in June to boost the domestic soybean industry.

"At a time when many farmers are struggling to break even, all federal biofuels policies should prioritize domestic agriculture and biofuel production," US Senator Chuck Grassley, Republican-Iowa, said in a note Oct. 2.

In June, the EPA proposed record biomass-based diesel or BBD volumes in its "Set 2 proposal" and included a 50% reduction in renewable identification numbers or RIN values for imported renewable fuels and fuels made from foreign feedstocks.

Source: US EPA "RFS Set 2 Rule" proposal

In their letter to the EPA, the senators said that an increased biodiesel mandate could provide timely support to soybean farmers in the country as they face uncertainty in the foreign market.

Roughly a quarter of each soybean's bushel value processed in the US is directly linked to biofuel demand, the senators said in the letter.

Support for US soybeans

US soybean exports have decreased significantly this year as China, usually its biggest buyer, reduced purchases due to the ongoing tariff war.

From January through August 2025, US soybean exports to China totaled just 218 million bushels, down sharply from 985 million bushels in 2024, when China purchased about half of all US soybean exports, the US farmer trade body the American Farm Bureau Federation (AFBF) said Oct. 2.

Soybeans have become the clearest signal of stress in US agricultural trade. During June-August, the US shipped virtually no soybeans to China, AFBF said.

Senator Grassley said that, at a time when many farmers are struggling to break even, all federal biofuels policies should prioritize domestic agriculture and biofuel production, not foreign fuels made from foreign feedstocks.

The US EPA is still collecting comments from across the industry before finalizing the RFS mandate for 2026 and 2027. However, biofuel and petroleum groups are at odds over small refinery exemptions, which are waivers that allow certain small oil refineries to be excused from their RFS obligations.

A comment period on SRE reallocations will close on Oct. 31. Market participants expect the EPA to release a final "Set 2" rule soon afterward.

However, the partial government shutdown that started on Oct. 1 could affect the timeline for the rulemaking.

Platts, part of S&P Global Energy, assessed ethanol 2026 D6 RINs at 100.5 cents on Oct. 2, up 5.8% since the start of the month.

Platts assessed biodiesel 2026 D4 RINs at 106.75 cents Oct. 2, up 5.4% from end-September.