May 5, 2021 | Policy Brief

Biden Administration Should Ascertain the Status of Iran’s Arak Reactor

May 5, 2021 | Policy Brief

Biden Administration Should Ascertain the Status of Iran’s Arak Reactor

The Biden administration says it wants to rejoin the 2015 Iran nuclear deal because the accord seals off Tehran’s pathways to nuclear weapons, one of which involves plutonium. Yet the accord will not prevent Iran from producing plutonium, even temporarily, unless Washington confirms the implementation of permanent changes to the proliferation-prone design of Iran’s IR-40 heavy water nuclear reactor at Arak.

Under the accord, formally known as the Joint Comprehensive Plan of Action (JCPOA), Iran may not build new heavy water nuclear reactors or reprocess plutonium for 15 years. Iran also committed to “redesign and rebuild” the 40-megawatt IR-40 reactor so as “to minimise the production of plutonium and not … produce weapon-grade plutonium,” which Tehran could further process to develop nuclear weapons. To that end, the JCPOA established an international working group to oversee what the accord called a “modernization project” for the IR-40. As of early 2020, a U.S. official told FDD, firms and consultancies in the United Kingdom, China, the Czech Republic, and Germany had contracted to perform the work.

As required by the JCPOA, the International Atomic Energy Agency (IAEA) verified the permanent disablement of the IR-40’s calandria, which is a metal lattice that holds reactor fuel rods. Thereafter, the IR-40 working group moved slowly on reaching agreement on the redesign, and construction lagged. In January 2019, the head of Iran’s Atomic Energy Organization, Ali Akbar Salehi, complicated matters when he said on state television that Tehran had prepared to reconstitute the reactor in case the deal fell apart.

Salehi further admitted that Iran had imported a spare set of pressure tubes, ostensibly to construct a duplicate calandria if needed. With a duplicate calandria, and unless the working group ensured additional, irreversible modifications to other reactor components and systems, the IR-40 could once again produce significant amounts of weapons-grade plutonium.

Salehi feared that had the IAEA known about the spare pressure tubes, it would have demanded that Iran destroy them. Yet even after Salehi’s revelation, the other parties to the JCPOA were silent on the matter. Nor did the IAEA report following up with Iran about the tubes, even though Tehran’s import was a clear violation of the deal’s intent to prevent use of the old reactor design.

Limited media reporting about the IR-40’s progress indicated other potential problems, including potentially reversible technical allowances made by the modernization working group. For example, the IR-40’s secondary cooling circuit, which became active in December 2019, may not have been irreversibly altered to suit the new proliferation-resistant design. Only the primary cooling circuit was modified.

According to Olli Heinonen, a distinguished fellow at the Stimson Center and former IAEA deputy director for safeguards, “The reactor has yet to be irreversibly modified not to produce plutonium in quantities of non-proliferation concern. This requires modifications both to the first and secondary [cooling] systems, and not just one of them.”

The working group’s decisions regarding the IR-40 have also been overly secretive, and the parties have failed to issue progress reports. Nor has the IAEA provided public updates.

Regardless of whether Washington re-enters the JCPOA, the Biden administration must ascertain whether the Arak reactor working group agreed to technical compromises that could permit Iran to revert to the previous design. If so, the administration should urge the working group to rectify those allowances.

The IAEA must demand that Iran account for the spare pressure tubes and destroy them. In addition, the IAEA should publicly report on the Arak reactor’s modernization to date. IAEA member states and the public should be able to assess the technical rigor behind the reactor’s reorientation and the status of Iran’s plutonium pathway to nuclear weapons.

Andrea Stricker is a research fellow at the Foundation for Defense of Democracies (FDD), where she also contributes to FDD’s Iran Program, International Organizations Program, and Center on Military and Political Power (CMPP). For more analysis from Andrea, the Iran and International Organizations programs, and CMPP, please subscribe HERE. Follow Andrea on Twitter @StrickerNonpro. Follow FDD on Twitter @FDD and @FDD_Iran and @FDD_CMPP. FDD is a Washington, DC-based, nonpartisan research institute focusing on national security and foreign policy.


International Organizations Iran Iran Global Threat Network Iran Nuclear Military and Political Power Nonproliferation