Russia
Siberian Chemical Combine (SKhK)
This page is part of the Facilities Collection.
Established in 1953 in Tomsk-7 (now known as Seversk), the Siberian Chemical Combine (SKhK) played an important role in the Soviet nuclear weapons program. The facility produced plutonium and highly enriched uranium (HEU), and fabricated HEU and plutonium warhead components. 1 Five plutonium production reactors, a reprocessing facility, a uranium enrichment plant, and a chemical and metallurgical weapon-component production plant were in operation at SKhK. 2 There were also fissile materials storage facilities.
Since Rosatom consolidated its weapons-related activities, SKhK is no longer formally involved in the production of nuclear warheads. Its HEU production ceased, and its last plutonium production reactor was shut down in 2008. 3 Rosatom has contemplated moving back to SKhK the plutonium component fabrication that had been previously consolidated at the Mayak plant in Ozersk. However, this decision was cancelled. 4 Studies suggest that, despite the halt of all weapons-related production activities at the facility, SKhK remains a major site for the storage and handling of weapon-usable fissile materials and nuclear weapons components. 5
At present SKhK produces uranium feedstock and enriched uranium, converts and stores fissile materials, and produces thermal and electric power for Seversk as well as Tomsk Oblast. 6 In addition to supplying some of Russia’s domestic LEU fuel needs, SKhK enriches reprocessed uranium for foreign customers. Under the U.S.-Russia HEU-LEU program, SKhK also purifies and converts weapon-grade HEU to uranium oxide, converts it to uranium hexafluoride (UF6), and downblends it. 7 Moreover, there is also a plutonium storage facility and an MHR high-temperature gas-cooled reactor under development at SKhK as part of U.S.-Russian technical cooperation on plutonium disposition. 8 Lab-to-lab work under the Department of Energy’s material protection, control, and accounting (MPC&A) Program has been ongoing since 1996. 9
Finally, reports also note that Seversk is one of the largest sites storing low- and intermediate- level wastes from reprocessing, with more than 30 million cubic meters stored via deep-well injection. 10
Glossary
- Nuclear weapon
- Nuclear weapon: A device that releases nuclear energy in an explosive manner as the result of nuclear chain reactions involving fission, or fission and fusion, of atomic nuclei. Such weapons are also sometimes referred to as atomic bombs (a fission-based weapon); or boosted fission weapons (a fission-based weapon deriving a slightly higher yield from a small fusion reaction); or hydrogen bombs/thermonuclear weapons (a weapon deriving a significant portion of its energy from fusion reactions).
- Highly enriched uranium (HEU)
- Highly enriched uranium (HEU): Refers to uranium with a concentration of more than 20% of the isotope U-235. Achieved via the process of enrichment. See entry for enriched uranium.
- Reprocessing
- Reprocessing: The chemical treatment of spent nuclear fuel to separate the remaining usable plutonium and uranium for re-fabrication into fuel, or alternatively, to extract the plutonium for use in nuclear weapons.
- Enriched uranium
- Enriched uranium: Uranium with an increased concentration of the isotope U-235, relative to natural uranium. Natural uranium contains 0.7 percent U-235, whereas nuclear weapons typically require uranium enriched to very high levels (see the definitions for “highly enriched uranium” and “weapons-grade”). Nuclear power plant fuel typically uses uranium enriched to 3 to 5 percent U-235, material that is not sufficiently enriched to be used for nuclear weapons.
- Fissile material
- Fissile material: A type of fissionable material capable of sustaining a chain reaction by undergoing fission upon the absorption of low-energy (or thermal) neutrons. Uranium-235, Plutonium-239, and Uranium-233 are the most prominently discussed fissile materials for peaceful and nuclear weapons purposes.
- Uranium
- Uranium is a metal with the atomic number 92. See entries for enriched uranium, low enriched uranium, and highly enriched uranium.
- Low enriched uranium (LEU)
- Low enriched uranium (LEU): Refers to uranium with a concentration of the isotope U-235 that is higher than that found in natural uranium but lower than 20% LEU (usually 3 to 5%). LEU is used as fuel for many nuclear reactor designs.
- Weapons-grade material
- Weapons-grade material: Refers to the nuclear materials that are most suitable for the manufacture of nuclear weapons, e.g., uranium (U) enriched to 90 percent U-235 or plutonium (Pu) that is primarily composed of Pu-239 and contains less than 7% Pu-240. Crude nuclear weapons (i.e., improvised nuclear devices), could be fabricated from lower-grade materials.
- Downblending
- Downblending: Refers to the process of blending down HEU to LEU. This is done by mixing HEU and the blendstock (of natural, depleted, or slightly enriched uranium) in either liquid or gas form. See highly enriched uranium and low enriched uranium.
Sources
- Oleg Bukharin, “Downsizing Russia’s Nuclear Warhead Production Infrastructure,” The Nonproliferation Review, Spring 2001, pg. 117.
- Pavel Podvig, “Consolidating Fissile Materials in Russia’s Nuclear Complex,” IPFM research report, May 2009, pg. 11, www.ipfm.org.
- Pavel Podvig, “Russia No Longer Produces Weapon Materials,” IPFM blog, April 15, 2010, fissilematerials.org.
- Pavel Podvig, “Consolidating Fissile Materials in Russia’s Nuclear Complex,” IPFM research report, May 2009, pg. 7, www.ipfm.org.
- Pavel Podvig, “Consolidating Fissile Materials in Russia’s Nuclear Complex,” IPFM research report, May 2009, pg. 12, www.ipfm.org.
- “Общая информация об ОАО «СХК»” [General information about OJSC SKKh], 2011 Annual Report, www.atomsib.ru.
- Pavel Podvig, “Consolidating Fissile Materials in Russia’s Nuclear Complex,” IPFM research report, May 2009, pg. 12, www.ipfm.org.
- “Russia’s Nuclear Fuel Cycle,” World Nuclear Association, August 2012, www.world-nuclear.org.
- Cheryl Rodriguez et al, “Operational Experience: Upgraded MPC&A Systems for the Radiochemical Plant of the Siberian Chemical Combine,” Brookhaven National Laboratory paper, 2004, www.bnl.gov.
- “Russia’s Nuclear Fuel Cycle,” World Nuclear Association, August 2012, www.world-nuclear.org.