NNSA's Jill Hruby holds up a signed version of the MOU as her Japanese colleague, on video, does the same.
NNSA's Jill Hruby holds up a signed version of the MOU as her Japanese colleague, on video, does the same.

Agreement caps a productive year in minimizing Japan’s HEU

WASHINGTON – Building on years of close nonproliferation cooperation, the U.S. Department of Energy’s National Nuclear Security Administration (NNSA) and Japan’s Ministry of Education, Culture, Sports, Science and Technology (MEXT) announced a new commitment to convert the Kindai University Teaching and Research Reactor (UTR-KINKI) from highly enriched uranium (HEU) to low-enriched uranium (LEU) fuel and to return all HEU to the United States. 

Following the removal of all HEU from the Kyoto University Critical Assembly, announced in August, UTR-KINKI is the last HEU-fueled research reactor in Japan, underscoring the importance of this new commitment to both countries. In May, President Biden and Prime Minister Kishida announced that NNSA and MEXT had removed more than 30 kilograms of HEU from three Japanese research reactors.

“This new agreement to convert UTR-KINKI—Japan’s last HEU-fueled research reactor—and to remove its HEU is the latest accomplishment in a remarkable year of U.S.-Japan nonproliferation milestones,” said NNSA Administrator Jill Hruby during a virtual signing ceremony. “We appreciate our close bilateral relationship with Japan and look forward to announcing the completion of this latest commitment in the coming years.”

Following conversion of the reactor to LEU fuel, the HEU will be securely transported to the United States for downblending to LEU and/or disposition.

NNSA’s Office of Material Management and Minimization works with partner countries and institutions around the world to eliminate the need for, presence of, or production of weapons-usable nuclear material. To date, the office has converted or verified the shutdown of 108 research reactors and medical isotope production facilities and removed or confirmed the disposition of nearly 7,275 kilograms of weapons-usable nuclear material—enough for approximately 325 nuclear weapons.