See the Russian Weapons-Grade Fissile Material Cycle Chart that accompanies this overview.

Note: Weapons-grade uranium is usually defined as uranium containing more than 90% of the isotope U-235 and weapons-grade plutonium as highly pure Pu-239 that contains 6% or less of the isotopes Pu-240 and Pu-242 combined. About 15kg of weapons-grade HEU or 6kg of weapons-grade plutonium are required to build an implosion-type fission weapon. However, HEU of lower enrichment levels and non-weapons-grade plutonium can also be used to build nuclear weapons if large enough amounts are used and additional technical hurdles are overcome.

Between the mid-1940s and early 1960s, Russia had built the vast majority of its nuclear warhead production facilities, often referred to as the nuclear weapons complex. The complex encompasses facilities that design warheads, facilities that produce fissile materials (highly enriched uranium (HEU) and plutonium), facilities that fabricate fissile material components for nuclear warheads, and facilities that assemble and disassemble warheads. Building upon research and scientific expertise from its nuclear weapons program, Russia began developing its nuclear power industry in the mid-1950s.  

The Russian nuclear warhead research, design, production, and periodic maintenance complex is managed by the Russian Ministry of Atomic Energy (Minatom). (Note: The Ministry of Defense controls and monitors weapons-related operations at Minatom weapons facilities and assumes full control over warheads once they leave these facilities. Issues related to nuclear weapons and forces are covered in the Russian Nuclear Weapons section of the NIS database.) Minatom's complex consists of two parts. The defense complex (also referred to as the warhead production complex) develops and produces nuclear warheads and disposes of weapons-grade fissile material from weapons. It processes and stores large amounts of HEU and plutonium, mainly in the form of warhead components. Most of the facilities involved in the production of nuclear warheads and in the handling of weapons-grade fissile material are located in the 10 closed nuclear cities. Weapons-grade fissile material in the form of fresh and spent fuel is also handled at Russian naval facilities on shore and on board submarines and ships. Fresh fuel for Russian naval reactor cores contains uranium enriched to between 21 to 90 percent. The civilian complex includes nuclear fuel production facilities, nuclear power plants, non-weapons research facilities, and educational and industrial facilities. These facilities handle large amounts of non-weapons-grade fissile material and some handle significant amounts of weapons-grade HEU and plutonium for fuel production, experiments and research purposes.[1] The exact amount of HEU and/or plutonium at a particular site is often unknown; the best available estimates are provided in the Russian Fissile Material Table. Military and civilian activities involving fissile material are often found within the same facility or site. For example, Mayak Production Association (PO Mayak) handles plutonium not only in the process of warhead component fabrication and maintenance but also in mixed-oxide (MOX) fuel research, experimental MOX fuel production, and spent fuel reprocessing. 

The Russian Weapons-Grade Fissile Materials Cycle Chart illustrates the flow of weapons-grade fissile material and lists facilities involved in handling HEU and plutonium at different stages of the Russian fissile material and warhead production cycles. It highlights sections covering HEU and Plutonium Production and Warhead Assembly; Warhead Stockpile Maintenance; and HEU and Plutonium Disposition and Utilization within both the civilian and defense complexes. Information on specific facilities can be obtained by clicking on the name of the facility within the chart.

In 1988 the Soviet Union stopped uranium enrichment for weapons. Three facilities were involved in weapons-grade HEU production up to that point—the Urals Electrochemical Combine (UEKhK), the Siberian Chemical Combine (SKhK), and the Electrochemical Plant (EKhZ). As of May 2001, these facilities are involved in down-blending HEU to low enriched uranium (LEU), uranium enrichment for nuclear fuel, and research and production activities involving uranium in different isotopic forms. HEU removed from retired or disassembled weapons is added to Russia’s stockpile. Exact numbers for Russia’s weapons-useable fissile material stockpile are unknown due to its classified nature. However, it is estimated that overall Soviet/Russian production of HEU totaled at least 1,200 metric tons (t) while overall production of plutonium totaled at least 150t. Over half of these amounts, approximately 650t, is estimated to be outside of nuclear weapons.[2] Ten plutonium breeder reactors were shut down between 1987 and 1992; however, three plutonium production reactors, two at the Mining and Chemical Combine (GKhK) and one at SKhK, continue to operate and produce plutonium.[3] According to the US-Russia Agreement Concerning the Shutdown of Plutonium Production Reactors and the Cessation of Use of Newly Produced Plutonium for Nuclear Weapons signed in June 1994, Russia agreed to cease using plutonium from its breeder reactors for new nuclear weapons.[4]  Reprocessing of spent nuclear fuel and the associated separation of plutonium continues at PO Mayak. Plutonium recovered from the reprocessed spent fuel is reactor grade, not weapons grade.

Arms control treaties, downsizing and conversion of facilities to non-military production, and bilateral agreements with the United States on fissile material disposition such as the US-Russia HEU Deal (1993) and the US-Russia Plutonium Disposition Agreement (2000) have all forced dramatic changes upon Russia’s weapons and civilian nuclear complex and have led to a reduction in the number of facilities involved in the nuclear defense program. As of April 2001, fissile material warhead component fabrication has been reduced to only one facility - PO Mayak in Ozersk. The other fissile material component manufacturing site in Seversk is believed to be engaged solely in fissile material component disassembly.[5] New warhead assembly, in which nuclear pits and other components are combined, was formerly  undertaken at four facilities referred to as the “serial production facilities” (Avangard EMZ, the Instrument-Making Plant, Start Production Association, and Elektrokhimpribor Combine); as of May 2001, it is being conducted at two facilities: Elektrokhimpribor Combine in Lesnoy and the Instrument-Making Plant in Trekhgornyy.[6] For more information on warhead production facilities, see the Nuclear Warhead Production Complex Overview in the Russia: Weapons Facilities section.   

Russian warheads contain electronic, fissile material and chemical components with limited service lives that require routine maintenance or modernization to ensure their safety and security. Once it is determined that a nuclear warhead requires maintenance, whether scheduled or otherwise, the process of warhead disassembly, fissile component disassembly, fissile material processing,  re-manufacturing, and warhead re-assembly occurs.  Warhead disassembly occurs at the four serial production facilities. The remanufacturing of a fissile material component involves the disassembly of an old pit, purification of the plutonium, and manufacture of a new pit. Fissile material components from dismantled warheads are disassembled at either PO Mayak or the Siberian Chemical Combine.[5] Re-manufacturing of warhead pits occurs at PO Mayak. The new pits are then transported to one of two assembly facilities, either the Elektrokhimpribor Combine or the Instrument Making Plant, where they are combined with other weapons components.[6] 

Fissile material that is not used for new warhead production or that is taken from older weapons is either stockpiled for future use, earmarked for research, processed by nuclear fuel cycle facilities to produce fresh reactor fuel, or slated for disposition under international agreements. The Siberian Chemical Combine and PO Mayak serve as the major storage facilities for fissile material components from dismantled warheads.A Fissile Material Storage Facility (FMSF) at PO Mayak is being constructed with US funds under the auspices of the Cooperative Threat Reduction (CTR) program and is intended to become the central storage facility for weapons-grade material from dismantled nuclear weapons.

HEU that is not earmarked for the weapons program is processed and fabricated into a variety of types of nuclear reactor fuel, including fuel for research reactors, plutonium, and tritium production reactors, space reactors, and for naval propulsion. Under the US-Russia HEU Deal 500 metric tons (t) of Russian HEU is being downblended into LEU and sold to the United States.

Until recently, most excess weapons-grade plutonium was stockpiled, with only small quantities used for research and experimental production of MOX fuel. According to the September 2000 US-Russia Plutonium Disposition Agreement, 34t of weapons-origin Russian plutonium has been earmarked for disposition by converting it into MOX fuel. The resulting MOX fuel would then be burned in both fast breeder and light-water reactors.

For more information on issues related to fissile materials in Russia, Minatom’s nuclear complex, and international agreements and programs to dispose of weapons-grade nuclear material, see the following sections of the NIS nuclear profiles database:
 

	Russia: Overview of Fissile Material Production
	Russia: Nuclear Warhead Production Complex Overview
	Russia: Plutonium Production Overview
	Russia: Uranium Enrichment Overview
	Russia: Overview of Uranium Refinement, Fuel Fabrication, and Reprocessing
	Russia: Naval Nuclear Reactors Overview
	Russia: Nuclear Power Reactors
	Russia: Research Facilities With Reactors and Critical/Subcritical Assemblies
	Russia: Spent Fuel and Radioactive Waste
	Russia: Overview of the US-Russian HEU Agreement
	Russia: Plutonium Disposition Overview
	Russia: Plutonium Disposition Developments
	Russia: MOX Fuel Overview
	Russia: MOX Fuel Developments

Sources:
[1] Oleg Bukharin, “Security of Fissile Materials in Russia," Annual Review of Energy and the Environment, No. 21, 1996, pp. 467-90.
[2] “The Proliferation of Weapons of Mass Destruction: How Much of a Challenge,” Remarks of Ambassador Eileen Malloy, US Department of Energy, 12 December 1999, presented to CNS conference “Assessing US Dismantlement and Nonproliferation Assistance Programs in the Newly Independent States,” Monterey, California, 11-13 December 1999.
[3] Thomas Cochran et al., Making the Russian Bomb: From Stalin to Yeltsin (Boulder: Westview Press, 1995), pp. 277-84.
[4] 1994 Agreement Between the Government of the United States of America and the Government of the Russian Federation Concerning the Shutdown of Plutonium Production Reactors and the Cessation of the Use of Newly Produced Plutonium for Nuclear Weapons, http://www.eia.doe.gov/gorec/gcc8.html.
[5] NISNP Staff Interview with Russian scientist, April 2001.
[6] Oleg Bukharin, “Downsizing Russia’s Nuclear Warhead Production Infrastructure,” The Nonproliferation Review, Spring 2001, p. 124. {Entered 5/2/01 GD}

Page last updated 4 June 2001
For major recent developments, see the Nuclear Fuel Cycle Developments file

Comments or questions? Contact Elena Sokova at MIIS CNS: esokovaATmiis.edu