Japan Ships Out Highly Enriched Uranium


September 2022
By Kelsey Davenport

The U.S. Department of Energy announced in August the completion of a multiyear project to transfer 45 kilograms of highly enriched uranium (HEU) from Japan to the United States.

The HEU came from the Kyoto University Critical Assembly and fulfilled a commitment that Tokyo made at the 2016 nuclear security summit to remove all HEU from that reactor. Minimizing and disposing of HEU was a key goal of the nuclear security summit process, a six-year multilateral effort from 2010 to 2016 to prevent nuclear terrorism.

The HEU will be down-blended at the Y-12 National Security Complex in Tennessee and the Savannah River Site in South Carolina to lower enrichment levels that pose less of a security risk.

In an Aug. 9 press release, Jill Hruby, administrator of the National Nuclear Security Administration (NNSA), said that the campaign to remove the HEU was a “monumental effort.” As a result, the Kyoto University Critical Assembly can continue its work “without risk that the fuel could be used to produce an improvised nuclear device,” she said.

The NNSA worked with the Japanese Ministry of Education, Culture, Sports, Science and Technology to complete the disposition. The governmental agencies aim to complete conversion of the reactor to run on low-enriched uranium fuel by the end of 2023.