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June 1, 2018
Going Nowhere Fast: Iran's Arak Reactor

Arms Control NOW

As the most recent round of negotiations between Iran and the P5+1 (China, France, Germany, Russia, the United Kingdom and the United States) wound down on November 10, an unlikely player emerged center-stage in the press coverage of the negotiations: the Arak heavy water reactor.

The Arak reactor represents a potential second pathway for Iran to produce fissile material for nuclear weapons. Heavy water reactors are particularly well-suited for plutonium production, which must be separated from the radioactive spent fuel of the reactor if it is to be used for weapons. For this reason, the Arak reactor project has been an item of concern for years and the P5+1 group have called on Iran to halt progress toward its completion.

Iran is making slow progress on the Arak heavy water reactor.

The "first phase" agreement under consideration would include steps related to Arak, perhaps by halting further work on fuel assembly manufacture. The latest International Atomic Energy Agency (IAEA) quarterly report on Iran's nuclear program shows that reactor is still many months – if not years – away from completion. This underscores the fact that Arak is a long-term proliferation risk -- not a near-term risk-- and that a final resolution to Arak does not have to be negotiated in the "first phase" agreement now being negotiated by the P5+1 and Iran. Iran began construction of the Arak IR-40 heavy water reactor in 2004. It was originally scheduled to be completed by 2009.

In early November 2006, the Arms Control Association published an Issue Brief by State Department nonproliferation official Robert J. Einhorn highlighting the proliferation potential of Arak and recommending that the IAEA Board of Governors halt all technical cooperation from the Agency to Iran in connection with the reactor and it did so. (See The New York Times, "As Iran Seeks Aid, Atom Agency Face Quandry," Nov. 20, 2013.) Since that time the project has been beset by delays caused by technological problems and the inability of Iran to obtain the right materials to finish the job and Iran has not provided the IAEA with updated design information on the reactor project.

According to the IAEA's latest quarterly report, Iran installed no major components of the reactor between August and November. The only development noted in the report was that Iran completed connecting the reactor vessel to the cooling and moderator piping. Still missing are the control room equipment, refueling machines and cooling pumps, according to the November 14, 2013 report. This slow progress caused Iran to revise its timetable for operating the reactor yet again in August. At that time, Iran told the IAEA that introducing the nuclear material into the reactor in the first quarter of 2014 is no longer feasible. And while Iran did not give the IAEA a new date for the start-up of the Arak reactor, Tehran has said that it would notify the IAEA at least six months in advance of introducing nuclear material into the facility. Iran also appears to be having trouble producing the fuel assemblies (made of natural uranium) necessary to run it.

Iran originally informed the IAEA last March that it planned to produce 55 fuel assemblies by August. According to the IAEA's November report, it only had 10, with another on the way. According to independent experts, the Arak reactor could contain about 180 fuel assemblies, and require 100-150 to achieve criticality.

Now, Iran has revised its estimate, telling the IAEA on November 4 that it plans to produce 140 by August 2014. Again, this delay in producing the assemblies demonstrates that the Arak reactor is not a near-term risk that requires a final resolution in a "first-phase" agreement aimed at pausing the progress of Iran's nuclear fuel cycle projects.

However, the Arak reactor does need to be addressed in the final, comprehensive deal because when and if it becomes operational, the Arak heavy water reactor could produce an estimated 9-10 kilograms of plutonium every year. That would be enough for two nuclear weapons if Iran had a facility to separate the plutonium from the spent fuel--a facility Tehran does not have and that its says it doesn't intend to build.

To remove the proliferation potential of Arak, the final P5+1 deal could include an indefinite halt to all construction involving nuclear components, arrangements to ship spent fuel produced by Arak out of Iran for disposition in a third country (such as Russia), or an agreement that Arak will be converted to a less proliferation sensitive light-water reactor.