US regulator authorises Urenco plant to increase enrichment

The Urenco USA centrifuge enrichment plant is the only operating commercial uranium enrichment facility in North America – and increasing its enrichment limit to 10% uranium-235 is a significant step forward for the US civil nuclear industry, the company said.

According to an entry in the US Federal Register, the NRC staff is issuing an environmental assessment and a finding of no significant impact – also known as a FONSI – for the application to amend the plant’s licence to increase allowed enrichment from the current limit of 5.5 weight percent U-235 (low-enriched uranium or LEU) to less than 10 weight percent U-235 (known as LEU+). The next step will be an NRC review of Urenco USA’s implementation of requirements in the amendment, which is anticipated in late Spring 2025. Urenco USA (UUSA) will be authorised to produce enrichment levels up to 10% U-235 in all cascades at the facility.

“This positive progress is important to support the nuclear industry to create fuels that will reduce outage cycles for current reactors, provide fuels for some advanced reactor types, and assist our current and future customers”, said UUSA Managing Director John Kirkpatrick.

UUSA’s current capacity of 4.4 million separative work units (SWU) supplies one-third of the USA’s domestic enrichment demand, and is licensed to produce up to 10 million SWU, Kirkpatrick said. “Our strong infrastructure, deep expertise, and market longevity put us in a unique position to continue supporting the existing US nuclear fleet,” he added.”

U-235 is the main fissile isotope of uranium and occurs at a concentration of about 0.7% in natural uranium. Standard fuel used in today’s operating light water reactors uses LEU, with enrichment levels up to about 4.8% U-235. But higher-enriched – or LEU+ – fuel containing up to 10% U-235 can potentially offer improved nuclear fuel cycle economics for currently operating reactors.

Urenco subsidiary Louisiana Energy Services LLC was announced by the US Department of Energy (DOE) earlier this week as one of six companies selected to compete for contracts to supply the department with LEU. In October, it was one of four companies selected by the DOE to provide enrichment services to help establish a US supply of high-assay low-enriched uranium, enriched to between 5% and 20% U-235. Fuels containing this material – known as HALEU – will be required to fuel many of the advanced reactors and small modular reactors that are now being developed.