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ISIS Reports

Is Iran Building a Third Enrichment Plant?

by David Albright and Andrea Stricker

June 4, 2012

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The May 25, 2012 International Atomic Energy Agency safeguards report on Iran calls on Iran to declare if it is building new nuclear facilities, including a third gas centrifuge plant.

Is Iran building a third gas centrifuge enrichment plant?  This question has been on the minds of Iran watchers in governments around the world since former Iranian nuclear chief Ali Akbar Salehi claimed on August 16, 2010 that “studies for the location of 10 other uranium enrichment facilities” had ended, and that “the construction of one of these facilities will begin by the end of the (current Iranian) year (March 2011) or start of the next year.” 1  Succeeding nuclear head Fereydoun Abbassi-Davani said in mid-2011 that construction on additional enrichment plants was delayed by two years. 2  Now, one year later, what is the status of a new centrifuge plant in addition to the Natanz and Fordow centrifuge plants? Is the plant still deferred for another year or has Iran changed its mind once again and begun building a third centrifuge plant in secret?  It would not be the first time, as witnessed by Iran’s past secret construction of the Natanz centrifuge site, the Kalaye Electric centrifuge research and development plant, and the deeply buried Fordow centrifuge facility.

Since March 2007, Iran has taken the position that it does not have to notify the International Atomic Energy Agency (IAEA) if it begins construction of a nuclear facility, but the IAEA says that Iran has a legal obligation to do so under its current safeguards agreement.  Iran’s provision of information about the construction of any new enrichment sites is pertinent to instilling confidence about the peaceful nature of its nuclear activities and satisfying international concern that it could decide to make weapon-grade uranium in secret. 

Iran’s Legal Requirement to Declare Any Centrifuge Plant Under Construction

The IAEA states that Iran has a legal obligation to comply with modified Code 3.1 of the Subsidiary Arrangements General Part to Iran’s Safeguards Agreement. Modified Code 3.1 provides for the submission to the IAEA of design information for new facilities as soon as the decision to construct, or to authorize construction of, a new facility has been taken, whichever is the earlier.

The IAEA notes in its May 2012 Iran safeguards report that “Iran remains the only State with significant nuclear activities in which the Agency is implementing a comprehensive safeguards agreement but which is not implementing the provisions of the modified Code 3.1.”  In 2003, Iran accepted modified Code 3.1 but reneged unilaterally in March 2007. 3

Since then, the IAEA has called on Iran to comply with its legal obligations, which states that Iran cannot unilaterally abandon its safeguards obligations under modified Code 3.1. The May 25, 2012 IAEA safeguards report reiterated the IAEA’s legal position: “In accordance with Article 39 of Iran’s Safeguards Agreement, agreed Subsidiary Arrangements cannot be changed unilaterally; nor is there a mechanism in the Safeguards Agreement for the suspension of provisions agreed to in the Subsidiary Arrangements. Therefore, the modified Code 3.1, as agreed to by Iran in 2003, remains in force. Iran is further bound by operative paragraph 5 of Security Council resolution 1929 (2010) to ‘comply fully and without qualification with its IAEA Safeguards Agreement, including through the application of modified Code 3.1’.” 

Need for More Transparency

In response to Salehi’s August 2010 announcement, the IAEA asked Iran in a letter dated August 19, 2010 to provide preliminary design information for this third centrifuge facility.  In a letter a few days later, Iran did not provide the requested information and stated only that it would provide the Agency with the required information “in due time.”

Iran has taken the position that it can delay telling the IAEA about the construction of a nuclear facility until six months before the introduction of nuclear material, based on its original, unmodified safeguards agreement.  Thus, under Iran’s interpretation of its safeguards obligations, Iran can essentially finish construction of a gas centrifuge plant before notifying the IAEA of its existence. Iran is trying to assert that is has a right to build a centrifuge plant in secret.

Iran’s decision to defy the IAEA only increases concern that its intentions are to build nuclear weapons.  Iran may not in fact declare a plant’s existence six months before introducing nuclear material but instead hold it in reserve for use in a future breakout.

ISIS has assessed that international concern over Iran’s ability to breakout in secret should increase in 2013 due to the possible construction of a hidden centrifuge enrichment site and simultaneously growing stocks of 3.5 and 19.75 percent low enriched uranium that would allow the speedier production of weapon-grade uranium. 4  It remains for Iran to abide by the simple provision, modified Code 3.1, to provide the IAEA with advance information about its construction of additional enrichment facilities and to explain any current construction of a third enrichment site.  In avoiding its responsibility under its safeguards agreement, Iran risks that any site subsequently discovered being built in secret will be viewed as a threat, increasing the risks of military confrontation.  Greater IAEA transparency serves the needs of all those opposed to nuclear weapons and committed to the peaceful resolution of conflict.



1 Fars News Agency, “Iran Specifies Location for 10 New Enrichment Sites,” August 16, 2010.
2 Siavosh Ghazi, “Iran atomic chief says fuel swap talks over: IRNA,” AFP, Aug 29, 2011
3  According to the May 23, 2007 IAEA Iran safeguards report, “On 29 March 2007, Iran informed the Agency that it had “suspended” the implementation of the modified Code 3.1, which had been “accepted in 2003, but not yet ratified by the parliament,” and that it would “revert” to the implementation of the 1976 version of Code 3.1, which only requires the submission of design information for new facilities “normally not later than 180 days before the facility is scheduled to receive nuclear material for the first time.”
4 David Albright, Paul Brannan, Andrea Stricker, Christina Walrond, and Houston Wood, Preventing Iran from Getting Nuclear Weapons: Constraining Its Future Nuclear Options (Washington, D.C.: Institute for Science and International Security, March 5, 2012).

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