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Natanz Enrichment Complex

  • Location
    Natanz, Iran
  • Type
    Nuclear-Enrichment
  • Facility Status
    Operational

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About

Natanz is Iran’s primary enrichment facility and houses both the commercial Fuel Enrichment Plant (FEP) and the Pilot Fuel Enrichment Plant (PFEP). 1 The facility consists of three underground buildings, two of which are designed to hold 50,000 centrifuges, and six above ground buildings. Two of the above ground buildings are 2,500 meter halls used for gas centrifuge assemblies. 2 The nuclear material and enrichment equipment located at the FEP and PFEP are under IAEA safeguards. 3

Iran covertly moved its gas centrifuge research, development, and assembly operations to Natanz from the Kalaye Electric Company in 2002. 4 The operation did not remain secret for long, however, because the opposition group The National Council of Resistance of Iran publicly identified the site in August 2002. The revelations prompted Gholam Reza Aghazadeh, President of the Atomic Energy Organization of Iran, to reveal Iran’s intention to develop the full nuclear fuel cycle at the 2002 IAEA General Conference. 5 During IAEA Director General Mohammed El-Baradei’s follow-up visit in February 2003, Tehran officially declared that it was constructing the FEP and the PFEP at Natanz. 6

In October 2003, France, Germany, the United Kingdom, the European Union and Iran commenced negotiations on suspending Iran’s enrichment and conversion activities. 7 In addition to ceasing such activities, Iran agreed to halt manufacturing and assembling centrifuge parts at its enrichment installations. 8 The suspension was maintained through the duration of talks with the E3 and EU in November 2004. 9 Following the election of the conservative President Mahmoud Ahmadinejad in August 2005, however, Iran began to backtrack on cooperative agreements with the IAEA. On January 10, 2006, Iran broke the seals safeguarding Natanz and resumed its enrichment program. Shortly thereafter, Iran introduced UF6 into the gas centrifuges at the PFEP, and by February 2007 it had started feeding UF6 into the cascades installed at the FEP. 10

With negotiations over Iran’s nuclear program deadlocked in 2006, the George W. Bush administration initiated a cyber-warfare operation, code-named “Olympic Games,” aimed at sabotaging Iran’s growing enrichment activities through a slow barrage of cyber-strikes. 11 Popularly known as “Stuxnet,” the virus, which was developed with the help of Israeli intelligence agencies, targeted the computer systems that commanded the centrifuges at Natanz. Designed to produce continuous, incremental damage rather than a catastrophic, one-hit strike, the virus caused the centrifuge rotors to spin uncontrollably fast. These substantial increases in velocity led to a destructive rise in the rotor wall pressure, thereby causing the centrifuges to break. 12 After assuming office in 2009, President Obama intensified the program, gradually increasing the rate and severity of attacks on Natanz’s enrichment complex. According to IAEA reports, between the end of 2009 and early 2010 Iran decommissioned and replaced approximately 1,000 centrifuges at Natanz due to damage from the Stuxnet virus. 13 In November 2010, Iran temporarily suspended enrichment activities at the FEP amid growing issues with centrifuge operations. Estimates of Stuxnet’s success vary, as some Obama administration officials believe the cyber-attack delayed Iran’s nuclear development by 18 months to two years. Other assessments are more critical of Stuxnet’s significance and point to the quick recovery of centrifuge activity at Natanz following the facility’s brief shutdown. 14

As negotiations over Iran’s nuclear program proceeded in fits and starts, the Iranian government notified the IAEA in January 2013 that it planned to install more than 3,000 of the country’s advanced centrifuges, the IR-2m. 15 More durable and efficient than the IR-1 model, these centrifuges were capable of significantly increasing Iran’s output of enriched uranium. 16 The declaration signaled another step by Iran towards expanding its enrichment program in violation of IAEA Board of Governors and UN Security Council resolutions.

On November 24, 2013, Iran and the P5+1 (China, France, Germany, Russia, the United Kingdom and the United States) concluded a Joint Plan of Action (JPOA) to place a temporary freeze on Iran’s nuclear program and lay the groundwork for a more sweeping, long-term agreement. Under the JPOA, Iran agreed to cap its uranium enrichment operations at Natanz, begin diluting its LEU stockpile, and discontinue the installation of new centrifuges at the FEP. It also gave the IAEA broader access to the facilities at Natanz. 17

Using the JPOA as a foundation for a more comprehensive agreement, Iran and the P5+1 concluded the Joint Comprehensive Plan of Action (JCPOA) on 14 July 2015, a far-reaching 25-year settlement that constrained Iran’s nuclear capacity in exchange for sanctions relief. In accordance with the JCPOA, Iran agreed to remove approximately two-thirds of Natanz’s centrifuges, limit uranium enrichment to 3.67 percent, and down-blend or sell the majority of its LEU stockpile. Iran is also required to provide the IAEA daily access to Natanz for continuous monitoring of enrichment activities and centrifuge production. 18

Glossary

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.
Centrifuge
Centrifuge: A machine used to enrich uranium by rapidly spinning a cylinder (known as a rotor and containing uranium hexafluoride gas) inside another cylinder (called the casing).
International Atomic Energy Agency (IAEA)
IAEA: Founded in 1957 and based in Vienna, Austria, the IAEA is an autonomous international organization in the United Nations system. The Agency’s mandate is the promotion of peaceful uses of nuclear energy, technical assistance in this area, and verification that nuclear materials and technology stay in peaceful use. Article III of the Nuclear Non-Proliferation Treaty (NPT) requires non-nuclear weapon states party to the NPT to accept safeguards administered by the IAEA. The IAEA consists of three principal organs: the General Conference (of member states); the Board of Governors; and the Secretariat. For additional information, see the IAEA.
Safeguards
Safeguards: A system of accounting, containment, surveillance, and inspections aimed at verifying that states are in compliance with their treaty obligations concerning the supply, manufacture, and use of civil nuclear materials. The term frequently refers to the safeguards systems maintained by the International Atomic Energy Agency (IAEA) in all nuclear facilities in non-nuclear weapon state parties to the NPT. IAEA safeguards aim to detect the diversion of a significant quantity of nuclear material in a timely manner. However, the term can also refer to, for example, a bilateral agreement between a supplier state and an importer state on the use of a certain nuclear technology.

See entries for Full-scope safeguards, information-driven safeguards, Information Circular 66, and Information Circular 153.
Fuel Cycle
Fuel Cycle: A term for the full spectrum of processes associated with utilizing nuclear fission reactions for peaceful or military purposes. The “front-end” of the uranium-plutonium nuclear fuel cycle includes uranium mining and milling, conversion, enrichment, and fuel fabrication. The fuel is used in a nuclear reactor to produce neutrons that can, for example, produce thermal reactions to generate electricity or propulsion, or produce fissile materials for weapons. The “back-end” of the nuclear fuel cycle refers to spent fuel being stored in spent fuel pools, possible reprocessing of the spent fuel, and ultimately long-term storage in a geological or other repository.
International Atomic Energy Agency (IAEA)
IAEA: Founded in 1957 and based in Vienna, Austria, the IAEA is an autonomous international organization in the United Nations system. The Agency’s mandate is the promotion of peaceful uses of nuclear energy, technical assistance in this area, and verification that nuclear materials and technology stay in peaceful use. Article III of the Nuclear Non-Proliferation Treaty (NPT) requires non-nuclear weapon states party to the NPT to accept safeguards administered by the IAEA. The IAEA consists of three principal organs: the General Conference (of member states); the Board of Governors; and the Secretariat. For additional information, see the IAEA.
Uranium
Uranium is a metal with the atomic number 92. See entries for enriched uranium, low enriched uranium, and highly enriched uranium.
United Nations Security Council
United Nations Security Council: Under the United Nations Charter, the Security Council has primary responsibility for maintaining international peace and security. The Council consists of fifteen members, five of which—China, France, Russia, the United Kingdom, and the United States—are permanent members. The other ten members are elected by the General Assembly for two-year terms. The five permanent members possess veto powers. For additional information, see the UNSC.
P-5
P-5: The five permanent members of the United Nations Security Council: China, France, the Russian Federation, the United Kingdom, and the United States.
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.
Sanctions
Punitive measures, for example economic in nature, implemented in response to a state's violation of its international obligations.
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

  1. Institute for Science and International Security (ISIS), “Nuclear Sites: Facilities: Natanz,” ISIS Nuclear Iran, www.isisnucleariran.org.
  2. Institute for Science and International Security (ISIS),“Nuclear Sites: Facilities: Natanz,” ISIS Nuclear Iran, www.isisnucleariran.org.
  3. International Atomic Energy Agency, “Implementation of the NPT Safeguards Agreement and relevant provisions of Security Council Resolutions 1737 (2006), 1747 (2007), 1803 (2008), and 1835 (2008) in the Islamic Republic of Iran,” Report by the Director General, 28 August 2009, www.iaea.org.
  4. Institute for Science and International Security (ISIS), “Nuclear Sites: Facilities: Natanz,” ISIS Nuclear Iran, www.isisnucleariran.org.
  5. International Atomic Energy Agency, “Implementation of the NPT Safeguards in the Islamic Republic of Iran,” Report by the Director General, 6 June 2003, www.iaea.org.
  6. International Atomic Energy Agency, “Implementation of the NPT Safeguards in the Islamic Republic of Iran,” Report by the Director General, 6 June 2003, www.iaea.org.
  7. “Statement by the Iranian Government and Visiting EU Foreign Ministers,” IAEA and Iran, International Atomic Energy Agency, 21 October 2003, www.iaea.org.
  8. Daniel H. Joyner, Iran’s Nuclear Program and International Law, (New York: Oxford University Press, 2016), p. 216.
  9. “Paris Agreement: Agreement between Iran, Germany, United Kingdom and France,” Diplomatic News, Republique Francaise, 14 November 2004, www.ambafrance-ir.org.
  10. International Atomic Energy Agency, “Implementation of the NPT Safeguards Agreement in the Islamic Republic of Iran,” Report by the Director General, 28 April 2006, www.iaea.org; International Atomic Energy Agency, “Implementation of the NPT Safeguards Agreement and Relevant Provisions of Security Council Resolution 1737 (2006) in the Islamic Republic of Iran,” Report by the Director General, 22 February 2007, www.iaea.org.
  11. David E. Sanger, “Obama Ordered Wave of Cyberattacks against Iran,” The New York Times, 1 June 2012, www.nytimes.com.
  12. Ralph Langer, “Stuxnet’s Secret Twin,” Foreign Policy, 19 November 2013, www.foreignpolicy.com.
  13. Atika Shubert, “Cyber warfare: A different way to attack Iran’s reactors,” CNN, 8 November 2011, www.cnn.com.
  14. David E. Sanger, “Obama Ordered Wave of Cyberattacks against Iran,” The New York Times, 1 June 2012, www.nytimes.com.
  15. “Iran to upgrade nuclear program with faster IR-2m centrifuges to speed uranium enrichment, diplomats say,” CBS News, 31 January 2013, www.cbsnews.com.
  16. Kelsey Davenport, “Iran Installs Advanced Centrifuges,” Arms Control Today, 28 February 2013, www.armscontrol.org.
  17. “Joint Plan of Action,” 24 November 2013, https://assets.docum
  18. “The Iran Nuclear Deal: A Definitive Guide,” Belfer Center for Science and International Affairs, August 2015, www.belfercenter.org; “Section 3: Understanding the JCPOA,” Arms Control Association, 10 August 2015, www.armscontrol.org.

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