Removal of High-Enriched Uranium

The IAEA has assisted Bulgarian authorities with the removal of high-enriched uranium (HEU) stored at a shutdown research reactor in Sofia.

The HEU, 36% enriched and in the form of fresh fuel, was airlifted this month from Bulgaria to the Russian Federation, which agreed to take back the fuel and was the original supplier in the early 1960s for the small (2-megawatt) IRT research reactor in Sofia. IAEA safeguards inspectors monitored and verified the packaging of the fuel for transportation. Russia stated its intention to re-fabricate the fuel into low-enriched uranium.

The cost of fuel removal is being funded by the United States Department of Energy under a cooperative US-Russia-IAEA programme called the Tripartite Initiative, to further the aims of nuclear non-proliferation. The Tripartite Initiative facilitates the return of both fresh and spent fuel from Russian designed research reactors abroad.

The contract for the fuel's removal was concluded in early December between Bulgaria, represented by the Institute of Nuclear Research (IRNE)in Sofia, the Sosny Company in Russia, and the IAEA. The fuel's transport and removal operation was implemented within the scope of a regional IAEA technical cooperation project in which Bulgaria is engaged.

Bulgarian authorities consider the return of the HEU fresh fuel, and future construction of a low-power, low-enriched fuel research reactor at the same site, as an important phase of their technical cooperation with the IAEA. The planned reactor would mainly be used for education and training purposes.

There are currently about 80 research reactors around the world that still have HEU subject to international control as potentially weapons-useable material. The Agency has an active record in helping its Member States convert their research reactors from HEU to low enriched uranium, within the framework of programmes to improve the overall safety and security of research reactors, particularly ageing reactors, and their spent fuel storage facilities. In conjunction with a US-initiated international programme, the IAEA is helping to reduce and eventually eliminate international commerce in HEU for research reactors.

The Bulgarian removal and transport operation was carried out under the framework of the IAEA's Technical Cooperation programme in Europe, and involves the Agency's Departments of Safeguards, Nuclear Energy, Nuclear Safety and Security, Management and the Office of Legal Affairs.

This is not the first time the IAEA has helped to transfer HEU fuel back to its country of origin. In late September 2003, the IAEA assisted Romania, and in August 2002, Serbia and Montenegro.

Last update: 24 February 2015