In 1997, America's last bismuth refinery shut down. 29 years later, the metal is crucial to a 240-MW nuclear reactor whose coolant supply is 82% Chinese

In 1997, the United States lost its last domestic source of primary bismuth when a Nebraska refinery closed. Nearly three decades later, the metal is an important part of the cooling system for a proposed 240-megawatt advanced nuclear reactor in the US.

The reactor, called EAGL-1, is being developed by Indianapolis-based First American Nuclear, or FANCO. The company is also proposing a facility to manufacture the reactor's uranium fuel, while EAGL-1 would use liquid lead-bismuth as its coolant, as per an Autonocion report.

Bismuth makes up 55.5% of the alloy by atomic ratio, with lead accounting for the remaining 44.5%. China accounted for 82% of global refined bismuth production in 2023, according to US Geological Survey figures.

Why bismuth matters to EAGL-1

Lead-bismuth is attractive as a reactor coolant partly because bismuth lowers the alloy's melting point. The lead-bismuth eutectic melts at about 124°C, compared with 327°C for pure lead. That lower melting point is useful for a compact reactor design.

Bismuth is also one of the rarest elements in Earth's crust, ranking 65th in abundance. It is rarely mined directly and is generally produced as a byproduct of refining lead, tin, tungsten and fluorspar ores.

The US Geological Survey says the last domestic primary bismuth production came as a byproduct of lead refining at a Nebraska refinery that closed in 1997, as per the Autonocion report. The last bismuth in the National Defense Stockpile was also sold that year.

China now dominates refined bismuth

The US is now 89% reliant on net imports of bismuth, while China accounted for 82% of global refined production in 2023. Laos and South Korea supplied most of the remainder.

That concentration became more significant on February 4, 2025, when Beijing added bismuth to its export control and licensing list alongside indium, molybdenum, tellurium and tungsten.

Bismuth prices also rose sharply. Fastmarkets assessed bismuth metal in Rotterdam warehouses at $30 to $36 a pound by late March 2025, after prices had spent much of the previous decade in single digits.

Prices have since fallen from that spike, but the concentrated refining base remains relevant for EAGL-1 because its cooling system would depend on lead-bismuth.

FANCO is building the uranium side

On August 17, FANCO said the Nuclear Regulatory Commission had docketed its Regulatory Engagement Plan for a Category II high-assay low-enriched uranium deconversion and fuel fabrication facility, according to the Autonocion report.

The proposed plant would take HALEU in the form of uranium hexafluoride gas and convert it into solid uranium dioxide fuel pellets. HALEU, or high-assay low-enriched uranium, is enriched above 5% and below 20% U-235.

The facility would include a main process building for receiving, converting, fabricating, inspecting and shipping fuel, along with a secure storage vault, waste management area, analytical laboratory and administrative building with a security monitoring center.

It would not contain a reactor or critical assembly. According to the filing, all operations would remain subcritical by design.

The fuel facility is still years away

FANCO plans to submit its Part 70 license application in the fourth quarter of 2027. It has not yet selected a specific city or established property lines for the plant, although it has said the project falls within a roughly $4 billion footprint in Indiana.

The NRC's acceptance of the Regulatory Engagement Plan does not amount to approval to build or operate the facility.

The public filing also withholds the proposed fuel-making process. FANCO listed nine principal process steps, but all nine are redacted.

The company has identified areas for discussions with regulators, including UF6 deconversion, criticality safety, material accounting, physical security, emergency management and transportation of HALEU.

EAGL-1 is further along

EAGL-1 is a 240-MW small modular reactor with a fast spectrum and liquid lead-bismuth cooling. FANCO says six units in a cluster could provide enough electricity for roughly 1.2 million homes.

The company is targeting first power by 2033. FANCO has already submitted its own engagement plan to the NRC. AtkinsRéalis signed on in May as the exclusive engineering and construction management partner across North America, while Hyundai Engineering & Construction joined in July for balance-of-plant design.

Lead-bismuth has a nuclear history

Lead-bismuth cooling is not a completely new technology. The only reactors that operated using the coolant were Soviet naval units that powered a small number of Cold War attack submarines.

Nuclear Engineering International reported that the Soviet program was abandoned because of problems involving coolant solidification, corrosion and polonium-210.

The polonium issue comes from the chemistry of bismuth. Bismuth-209 can absorb a neutron and become bismuth-210, which beta-decays into polonium-210.

Polonium-210 is an alpha emitter with a 138-day half-life and is volatile enough to complicate maintenance during the plant's operating life.

The freezing problem is more immediate. If the lead-bismuth alloy falls below about 124°C anywhere in the primary circuit, it solidifies.

FANCO is testing materials

FANCO is addressing the corrosion challenge through physical testing. The company is building a lead-bismuth test loop and received two Department of Energy Nuclear Science User Facilities awards in August to irradiate candidate alloys.

One project involves FeCrAl-ODS steels at Oak Ridge, while another focuses on MA956 and is led by FANCO executive vice president of nuclear fuels Philip Jensen.

The testing will examine materials that would have to withstand exposure to hot liquid metal over the reactor's operating life.

The supply-chain gap

FANCO's proposed fuel facility would convert HALEU into the ceramic fuel needed by EAGL-1, while the reactor would also require lead-bismuth for its cooling system.

China's 82% share refers to global refined bismuth production in 2023, not to EAGL-1's future sourcing. FANCO has not said it would obtain any specific share of its bismuth from China.

The figure nevertheless illustrates a separate supply-chain issue for the project: the US has no domestic bismuth refining capacity, while most global refined production is concentrated elsewhere.

FANCO CEO Mike Reinboth has said that deploying nuclear power at scale requires a secure and capable American fuel supply, as per the Autonocion report.