Manasi Kakatkar
The National Nuclear Security Administration (NNSA) announced Oct. 7 that it had completely removed U.S.-origin highly enriched uranium (HEU) from Germany as part of its Global Threat Reduction Initiative (GTRI). With this action, the NNSA has so far removed all U.S.-origin HEU from a total of 16 countries. In 2008, material has been removed from Argentina, Portugal, and Romania.
HEU can be used to fuel nuclear reactors or serve as the fissile material for nuclear weapons. The International Atomic Energy Agency (IAEA) estimates that 25 kilograms of weapons-grade uranium is sufficient for a nuclear weapon.
This year the NNSA, a semiautonomous agency of the Department of Energy, has also successfully converted research reactors from using HEU to using low-enriched uranium (LEU) in Argentina, South Africa, and Ukraine and at the Institute of Nuclear Physics in Uzbekistan. All told, the NNSA has converted or shut down 62 HEU research reactors in 32 countries, including the United States. By 2018, the NNSA plans to have converted 129 of 209 research reactors to LEU. The remaining 78 reactors, NNSA officials said, cannot be converted as they are used for defense purposes or have a unique design.
The countries that agree to convert HEU reactors to LEU have their fresh and spent HEU and spent LEU shipped to the United States for secure disposition. Under the GTRI, the United States will accept U.S.-origin spent fuel from foreign reactors until 2019.
The U.S.-origin nuclear fuel return program undertaken since the 1990s has successfully removed more than 1,190 kilograms of HEU fuel from 27 countries. Since 2004, it has been a part of the GTRI.
Under the GTRI, the United States and Russia work closely together to remove fresh and spent HEU fuel. In February 2005, the two countries issued a Joint Statement on Nuclear Security noting that although the security of nuclear facilities in their countries meets current requirements, each country would work to safeguard their nuclear materials and facilities better. (See ACT, March 2005.)
Russia started accepting Russian-origin HEU fuel under its Russian Research Reactor Fuel Return program in 2002. It has so far received 764.4 kilograms of HEU fuel from 11 countries, including complete removal from Bulgaria and Latvia. On Oct. 23, NNSA officials announced that Russia had received its largest return shipment of HEU to date: 154.4 kilograms of spent HEU fuel. The HEU, retrieved from Hungary in October 2008, was said by the private Nuclear Threat Initiative to be enough for six nuclear weapons. Russia down-blends all received fuel to levels where the fissile isotope uranium-235 makes up less than 20 percent of the total uranium mix, an insufficient enrichment level for a nuclear explosive device.
Speaking Oct. 6 to an international gathering of experts seeking to reduce HEU use in research and test reactors, IAEA Deputy Director-General Yury Sokolov applauded the GTRI’s achievements. Sokolov also expressed concern that “about 150 civilian and military research reactors are still using HEU, and important quantities of fresh and spent HEU fuel continues to be stored in different countries.” He called for greater global action to eliminate civilian and eventually military use of HEU, for countries to declare their HEU stockpiles, and for states to establish a schedule to down-blend this material into LEU. Sokolov said, “The major obstacles to further minimization and eventual elimination of HEU are political and economic, not technical.”