WASHINGTON, Jan 8 (Reuters) - The U.S. agency in charge of nuclear security is commissioning a study on the proliferation risks of a more-enriched uranium fuel that nuclear power developers want to fuel new high-tech reactors, the head of the agency said this week.

Jill Hruby, administrator of the National Nuclear Security Administration, said in a statement published in the journal Science that it is important to address proliferation concerns of so-called high assay, low-enriched uranium fuel, or HALEU.

"NNSA recognizes that reactor type, fuel enrichment level, fuel quantity, and fuel form are important factors in evaluating proliferation risks and believes that risk-informed and adaptive approaches to the proliferation challenges inherent in nuclear energy are warranted," Hruby said.

Planned new nuclear plants, known as small modular reactors, or advanced reactors, must set high standards for safety and security, "especially considering Russia’s takeover of Ukraine’s largest nuclear power plant," she said.

Russia in 2022 took the Zaporizhzhia plant, the largest nuclear plant in Europe, by force after it invaded Ukraine.

Hruby's statement was in response to an article published last year in which scientists said HALEU poses a security risk because it can be used without further enrichment as fissile material in a crude nuclear weapon.

HALEU is uranium fuel enriched up to 20% instead of the 5% level of uranium fuel used in today's commercial reactors.

Several companies are hoping to develop a wave of reactors that would use HALEU, including the Bill Gates-backed TerraPower, which wants to build a $4 billion plant in Wyoming by 2030. Nuclear has gotten attention from technology companies seeking new ways to power data centers and as U.S. power demand is growing for the first time in decades. None of the plants have yet to be built.

TerraPower did not immediately respond to a request for comment.

In October, the U.S. Energy Department rolled out initial contracts to four companies hoping to produce HALEU domestically. Currently, commercial amounts of HALEU are only produced in Russia. The U.S. contracts will last up to 10 years and each awardee received a minimum of $2 million, with up to $2.7 billion available subject to congressional appropriations.

Hruby said NNSA has regularly collected data and evaluated HALEU risks, and is finalizing plans to commission a National Academies report. The reports are largely classified, she said. But the information will be used to inform programs, develop actions, and make recommendations to stakeholders.

Edwin Lyman, a physicist at the Union of Concerned Scientists and an author of last year's report, said he appreciated that Hruby is asking for the independent review of HALEU by the National Academies. "We are hopeful that this effort will lead to tighter security controls on HALEU to prevent its misuse by proliferators and terrorists."

The authors had written that if HALEU enrichment is limited to 10% to 12%, the supply chain would be far safer with only modest costs.

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https://www.reuters.com/business/energy/us-study-proliferation-risk-haleu-nuclear-fuel-after-warning-by-scientists-2025-01-08/