Misconceptions about Iran’s Nuclear Program
By David Albright and Jacqueline Shire
July 8, 2009
ISIS is proud of its work identifying clandestine nuclear programs and proliferation risks around the world and bringing impartial analysis to politically-charged and often technically complex issues. Although no country with a major nuclear program has escaped ISIS’s investigations over the years, we have spent considerable effort on Iran since 2002. ISIS has carefully chronicled Tehran’s development of the full nuclear fuel cycle, from uranium mining, to conversion, to a reactor and uranium enrichment. While diplomacy failed to arrest Iran’s progress over the last decade or so, Iran has succeeded in cobbling together an enrichment complex based on gas centrifuges, one with enough capability to produce enriched uranium for nuclear weapons, if the regime decides to do so. In terms of the number and type of centrifuges it is operating, Iran’s centrifuge program is comparable to Pakistan’s program in the early to mid-1980s.
While calling attention to Iran’s growing nuclear weapons capability, ISIS has consistently opposed the use of military force against Iran, arguing that doing so will only accelerate and drive underground its nuclear program, and is unlikely to achieve the objective of eliminating Iran’s many and dispersed nuclear-related facilities. A detailed assessment of Iran’s progress and ISIS’s recommendations to the Obama Administration can be found in our report Nuclear Iran: Not Inevitable.
We have received a range of comments on our analysis over the last six months in what is understandably a highly charged debate about identifying the best way to prevent Iran from building nuclear weapons. Some have criticized ISIS for overstating the ease with which Iran could make weapon-grade uranium, in essence inflating the risk of Iran’s nuclear program. Given ISIS’ own extensive and early criticism of faulty intelligence about Iraq’s alleged nuclear weapons programs in the run-up to the 2003 Iraq war, we understand those who view with skepticism any information indicating that Iran has not been fully forthcoming with the International Atomic Energy Agency (IAEA) or that it has technically achieved a nuclear weapons capability.
In the interest of promoting a broader understanding of technical issues about Iran’s uranium enrichment programs, ISIS has identified below several misconceptions about Iran’s nuclear program that have arisen in comments we have received or seen expressed in the broader news media. These misconceptions are as follows:
In fact, Iran’s violation of its obligations under the verification requirements of the Non-Proliferation Treaty (NPT) is one of most significant breaches of this treaty.
Iran’s safeguards violations have been detailed in numerous IAEA reports, which can be found here, starting in June 2003. The November 2003 report states that “based on all information currently available to the Agency, it is clear that Iran has failed in a number of instances over an extended period of time to meet its obligations under its Safeguards Agreement with respect to the reporting of nuclear material and its processing and use, as well as the declaration of facilities where such material has been processed and stored….” Iran’s development of its enrichment capability took place over 18 years and in secrecy. This places Iran’s actions outside the category of “minor.”
As a consequence of Iran’s safeguards violations, the United Nations Security Council has passed five resolutions, four of them containing sanctions, calling on Iran to halt uranium enrichment, accept the Additional Protocol, and comply with IAEA requests to clarify key past activities concerning the military dimensions of its program, including the role of military organizations in the centrifuge program and a set of records, referred to as the “laptop documents” which we discuss further in this document.”
It is also useful to recall, in the not-so-distant past, that Iran’s initial response to the IAEA’s requests for information (following the August 2002 allegations of secret nuclear activity by an Iranian opposition group) were initially met with resistance and outright concealment efforts. The November 2004 IAEA report enumerates Iran’s safeguards violations and notes that Iran’s cooperation up to October 2003 was marked by “extensive concealment, misleading information and delays in access to nuclear material and facilities.” Examples include its imports of nuclear material, falsehoods about the origin of centrifuge technology and equipment, and its enrichment activities at the Kalaye Electric Company workshop and at Lashkar Ab’ad , and suspected centrifuge-related activity at Lavizan-Shian.
Misconception 2. All of Iran’s nuclear facilities are under safeguards or monitoring, or alternatively the IAEA has found no evidence that Iran has any secret nuclear facilities
This is not the case. In fact, many key nuclear activities and facilities are not under any type of IAEA monitoring. This lack of Iranian transparency poses one of the most difficult challenges to determining whether Iran has undeclared nuclear activities and materials and is conducting nuclear weapons work.
The IAEA safeguards system in Iran is currently limited to traditional safeguards under an INFCIRC/153 agreement, which is part of Iran’s obligations under the Nuclear Non-Proliferation Treaty (NPT). The agreement applies to all of Iran’s sources of special fissionable material for the exclusive purpose of verifying that such material is not diverted to nuclear weapons or other nuclear explosive devices. Well-documented weaknesses in this agreement encountered during inspections in Iraq, North Korea, and South Africa in the early 1990s led the IAEA to develop the Additional Protocol. The protocol aimed to significantly strengthen the IAEA’s ability to detect undeclared nuclear materials and facilities, and ensure that a state’s declaration is complete. Although Iran initially agreed to allow this agreement in 2003, it then decided to no longer do so in 2006. Since then, the IAEA has reported that it is unable to determine if Iran has undeclared nuclear materials or activities. In the past, the IAEA has found evidence of secret nuclear sites. Now, the IAEA is limited in its ability to look for any such sites because of the weakened inspections and Iran’s interpretation of its obligations to the IAEA under that agreement.
A complete list of IAEA safeguarded facilities can be found here . In brief, the IAEA maintains safeguards at the Bushehr nuclear reactor, several facilities at Esfahan (including uranium conversion and fuel fabrication facilities), the Natanz fuel enrichment plants, the Tehran Research Reactor, a facility for radioactive waste storage facility and a laboratory.
Under INFCIRC/153, the IAEA does not safeguard or inspect several Iranian nuclear facilities and activities, in particular those involved in the research, development, and manufacture of gas centrifuges. Currently, the IAEA does not know the location of many of these sites. The IAEA also does not inspect the Arak heavy water production facility, which is outside the scope of inspections under INFCIRC/153.
Moreover, even at sites inspected by the IAEA, its rights, monitoring activities, and access are highly constrained under INFCIRC/153. Iran’s strict interpretation of this agreement and its often uncooperative approach, such as at the Natanz Fuel Enrichment Plant (where, for example, Iran has declined the IAEA’s request to place the centrifuge halls under remote camera monitoring), has further restricted the IAEA’s effort to increase the transparency of Iran’s declared nuclear activities.
Even under the relatively minimal requirements agreed under INFCIRC/153 and its implementing agreements, Iran has refused multiple IAEA requests to verify design information for the Arak heavy water reactor and its associated facilities currently under construction. The IAEA has stated that this refusal is inconsistent with its obligations under INFCIRC/153.
The IAEA also takes issue with Iran’s decision to stop providing information about new nuclear facilities when it makes a decision to construct them. Iran is insisting on adhering to a long outdated version of its safeguards undertakings by agreeing to provide such information only 180 days before the introduction of nuclear material into the facility. Iran initially agreed to provide early notification in 2003, but subsequently reversed its decision. The IAEA states that such a unilateral decision is inconsistent with Iran’s obligations under INFCIRC/153. This dispute is significant because Iran has built secret nuclear sites, including the Natanz gas centrifuge complex, exploiting this outdated arrangement. Iran confirmed its existence in early 2003 only after it was exposed publicly by groups such as ISIS. Gaining assurance that no such sites are under construction now is critical to ensuring that Iran is not trying to exploit this dispute to build nuclear facilities in secret.
Misconception 4. Producing HEU from LEU is a long and arduous process, and nuclear weapons breakout will take between one and three years
In fact, learning to produce enriched uranium by operating centrifuges in large numbers is the difficult part on the road to developing a viable gas centrifuge capability. Subsequently enriching low enriched uranium (LEU) to highly enriched uranium (HEU) is relatively straightforward and can be done quickly, in some cases within months. As a result, this process of enriching a stock of LEU to weapon-grade is called a nuclear weapons “break-out” capability.
Iran’s centrifuge program has advanced considerably in the last year (see charts below). Iran has succeeded in manufacturing and installing large numbers of centrifuges and ramping up its production of LEU. As of the end of May 2009, Iran had over 7,000 centrifuges enriching uranium or under vacuum and ready to enrich, and had produced over 1,300 kilograms of low enriched uranium hexafluoride. Although Iran’s centrifuges have experienced technical problems, they appear now to be working satisfactorily, and further improvement in centrifuge performance is expected.
ISIS has explored several paths to a breakout capability, here, here and here, whereby a stock of LEU could be further enriched to weapon-grade, either at a clandestine plant or at the Natanz enrichment plant (see also below). Our conclusion is that Iran has not made the political decision to develop a nuclear weapon, but that should its leadership so decide, Iran would have viable options for producing enough weapon-grade uranium for a nuclear weapon within six months or less.
Iran’s gas centrifuge program is currently large enough to provide Iran several ways to produce weapon-grade uranium. The time needed to produce enough weapon-grade uranium for a nuclear weapon is measured in months or a few years at most.
Iran currently operates enough centrifuges at the Natanz Fuel Enrichment Plant to produce weapon-grade uranium directly from natural uranium, if it decided to do so, though it would need to adjust the cascades or install a relatively small number of new cascades specifically for that purpose. As of the end of May 2009, the underground Natanz facility had 30 cascades, each with 164 P1 centrifuges, producing low enriched uranium with an average enrichment of about 3.5 percent. Another 13 cascades were under vacuum and able to start producing LEU. In total, these 43 cascades contained 7,052 P1 centrifuges. In comparison, a plant to make significant quantities of weapon-grade uranium requires fewer P1 centrifuges. The Pakistani A.Q. Khan provided Iran a design for such a plant in the mid-1980s.
A similar, if not identical, Pakistani-designed plant would contain 5,832 P1 centrifuges in 38 individual cascades, four sets of cascades would be producing enriched uranium in stages up to weapon-grade:
• Twenty-four cascades, each containing 164 centrifuges, for a total of 3,936 centrifuges, would in parallel enrich natural uranium to 3.5 percent enriched uranium.
• Eight cascades each containing 164 centrifuges for a total of 1,312, would enrich the 3.5 percent uranium to 20 percent.
• Four cascades, each containing 114 centrifuges, for a total 546 centrifuges, would in parallel enrich from 20 percent to 60 percent material.
• Finally, two cascades, each containing 64 centrifuges for a total of 128 centrifuges, would enrich the 60 percent material to 90 percent, or weapon-grade.
Each of these blocks of cascades would have its own feed and withdrawal system. A small fleet of vehicles would carry the uranium hexafluoride canisters among the various stations. The bulk of the enrichment effort goes into making the 3.5 percent enriched uranium, requiring 67 percent of the centrifuges.
The plant is estimated to be able to produce about 30-50 kilograms of weapon-grade uranium per year. The range reflects the relatively low enrichment output of the Iranian P1 centrifuges and inefficiencies in the Pakistan design. Iran would achieve higher weapon-grade uranium outputs if Iran increased its P1 centrifuges’ enrichment output, used higher tails assays, or substituted more powerful centrifuges.
The existing cascades at Natanz could already be used for the 3.5 to 20 percent enrichment stage since these include 164 P1 centrifuges (the number ascribed in the Pakistan-design) and would only require minor modifications in the feed and withdrawal system.
For the upper two stages, fewer P1 centrifuges would be used per cascade, but this is a straightforward modification of the existing cascades. Some modifications would be needed to address criticality risks in the feed and withdrawal portions of these cascades, such as using smaller product, feed, and tails canisters.
As an alternative to modifying the Natanz facility, Iran is capable of building a clandestine plant to make weapon-grade uranium from natural uranium. It has established at Natanz that it can build, install and operate large numbers of cascades. Given the risk of military strikes against Natanz if Iran were making weapon-grade there, it might prefer to build a parallel, secret plant. A major technical uncertainty is whether Iran can manufacture enough P1 centrifuges from its existing supply of materials for such a plant. Iran would also need a supply of uranium hexafluoride for such a facility; all of the uranium hexafluoride produced by Esfahan is under safeguards, so it would also likely need to construct a secret parallel facility to make uranium hexafluoride or acquire it illicitly from an overseas supplier.
Given Iran’s refusal to accept any but the weakest safeguards, the IAEA is unable to provide assurances about the absence of any undeclared nuclear materials or facilities. It has no access to centrifuge manufacturing workshops, making it difficult to know how many centrifuges are being produced and where they are stored. Adding in a long history of clandestine nuclear activities, the possibility of Iran building a secret gas centrifuge plant cannot be ruled-out. These considerations reinforce the importance of more intrusive IAEA inspections.
Iran could also produce weapon-grade uranium by further enriching its growing stock of LEU. It currently has enough LEU to produce sufficient weapon-grade uranium for one crude nuclear weapon. By early next year, this amount is expected to increase to enough for two nuclear weapons.
Iran could build a clandestine plant to further enrich the LEU to weapon-grade, reducing the number of centrifuges it would need at this plant by about two-thirds. It could also use its cascades at the Natanz plant.
All of Iran’s enriched uranium at Natanz is under IAEA safeguards. Any Iranian move to divert that material would likely involve denying the inspectors access to the plant and provoking an international crisis, possibly exposing key Iranian nuclear facilities to a military attack. The risk of attack might lead Iran to favor the clandestine route to the production of the weapon-grade uranium.
In order to produce weapon-grade uranium at Natanz or in a clandestine plant, a straightforward method is to add the top three stages in the Pakistani design. Ignoring cascades dedicated to making LEU from natural uranium in this design, the following would require a total of 2,844 P1 centrifuges and would make enough weapon-grade uranium from LEU for a crude nuclear weapon within 2.5 to 5 months:
• 12 cascades, 164 P1s per cascade for a total of 1,968 P1s, make 20 percent enriched uranium from 3.5 percent enriched uranium;
• 6 cascades, 114 P1s per cascade for a total of 684 P1s, go from 20 percent to 60 percent; and
• 3 cascades, 64 P1s per cascade for a total 192 P1s, go from 60 percent to 90percent.
Building these cascades and associated feed and withdrawal systems in a clandestine facility would be straightforward for Iran. Applying this approach at the Natanz facility is also uncomplicated. Any modifications required to establish the two highest stages at Natanz could be made while enriching up to 20 percent in the existing cascades. Using this arrangement, ISIS has estimated that Iran could produce sufficient weapon-grade uranium for one crude nuclear weapon in less than six months at Natanz.
Iran can reduce the time necessary to produce weapon-grade uranium at Natanz by advanced planning and pre-production of any equipment needed to make the modifications in the cascades. It could also make weapon-grade uranium faster by assigning more cascades to the various stages, forgoing the continued production of LEU. For example, it could dedicate one module of almost 3,000 centrifuges to producing only 20 percent enriched uranium and several additional cascades in another module to enriching from 20 percent to 90 percent. In a clandestine plant, Iran could add more centrifuge cascades.
The time needed with a clandestine plant is similar if not quicker given that the cascades would not require any modifications. Iran would need to build the plant, which ISIS estimates it could do in two years, based on its construction pace at Natanz. Ensuring that such a plant is not under construction is one of the reasons it is so important that Iran declare its nuclear facilities prior to starting construction and accept the Additional Protocol.
A fair question is when Iran might choose to break-out or develop a secret parallel centrifuge plant. The above discussion outlines technical milestones and methods of producing weapon-grade uranium as quickly as possible, based on Iran’s current centrifuge capabilities. Some argue that Iran would never break-out with only enough LEU to produce enough weapon-grade uranium to make one nuclear weapon, asserting instead that it would wait until it has enough for two, three, or even five nuclear weapons.
Because of a lack of information, this question is difficult to settle. Answering it also requires knowledge about Iranian intentions that cannot be determined with any degree of certainty. For example, under what conditions would Iran build nuclear weapons? Could events force Iran to seek nuclear weapons not at a time of its choosing? What purpose would its nuclear weapons serve initially? Does Iran want to develop a capability to rapidly conduct an underground nuclear test? Or does Iran want to wait until it can quickly deploy warheads that are deliverable by missiles? The former might necessitate several years while the former could be done much sooner. Another key consideration is what would be the negative consequences on Iran if it did break-out or launched a clandestine program to make weapon-grade uranium. Are the consequences severe enough to deter Iran? One hopes so.
In the absence of information about an Iranian strategy to acquire nuclear weapons and their purpose, ISIS has chosen a more technically defensible approach, to focus on technical milestones in Iran’s centrifuge program. It remains impossible to predict when Iran may decide to produce weapon-grade uranium or build nuclear weapons. The challenge for the international community is to ensure that day never comes.
Misconception 6. Iran would have to conduct a full-scale nuclear test in order to build a nuclear weapon
This fallacy confuses the approach taken by the United States during the Manhattan Project with those pursued by other states, such as Pakistan and South Africa. Developing an implosion-type nuclear weapon can be done without needing a full-scale test. Most states pursuing a clandestine nuclear weapons program have sought to avoid the need for full-scale testing. If a test is conducted, as it was by Pakistan and North Korea, it served to further refine nuclear weapons skills and more importantly demonstrate dramatically a strategic and political point.
States have used different options to avoid the need for tests. Pakistan did so after receiving a tested warhead design from China in the early 1980s. To develop confidence in its implosion design, prior to the Gulf War, Iraq was developing a set of tests of components and of the entire device with a surrogate material substituting for HEU. South Africa was likewise planning to pursue this approach for an implosion weapon. Iran would likely follow a path to maximize its flexibility and minimize its requirements for HEU.
Some have suggested that the issue of the so-called laptop documents was first raised with Iran by the IAEA in 2008. In fact, the story of the laptop documents was broken in 2005 and 2006 by three excellent reporters, Carla Anne Robbins, then at the Wall Street Journal, Dafna Linzer, at the time writing for the Washington Post, and Michael Adler, writing for the Agence France-Presse. Their articles describing the content and origins of the laptop as well as how it came into U.S. custody can be found here, here and here (subscription required for WSJ). U.S. officials briefed the IAEA on the contents of the so-called laptop documents in July of 2005. The February 27, 2006 IAEA report notes that on December 5, 2005 the IAEA “repeated its request for a meeting to discuss information that had been made available to the Secretariat about alleged studies, including what is known as the Green Salt Project, concerning the conversion of uranium dioxide into uranium tetrafluoride (often referred to as “green salt”), tests related to high explosives, and the design of a missile re-entry vehicle.
Iran agreed to the meeting in January and officials met February 26, 2006. Iranian officials responded that the allegations were “based on false and fabricated documents so they were baseless,” and that neither such a project nor such studies exist or did exist.” Later, Iran said that some of the documents were authentic but had nothing to do with nuclear weapons.
IAEA officials, who were quickly able to dismiss documents in the Niger/Iraq uranium episode (in which Iraq was alleged to have purchased illicitly 500 tonnes of uranium yellowcake) as forgeries, have not been able to make a similar determination in this case. IAEA analysts who reviewed the documents assessed that the volume of material, level of detail, including names, places and entities, do not support the conclusion that the documents are forgeries.
The IAEA has continued to pursue the matter with Iran. Its May 2008 report contains an annotated listing of thirteen documents related to the laptop or “alleged studies.” Iran has repeatedly refused IAEA requests to meet with individuals named in the documents, in particular Dr. Mohsen Fakhrizadeh, who appears to be at the center of the alleged nuclear weaponization-related research and development.
As soon as ISIS learned of these documents in 2005, it sought to independently determine if the documents were forgeries. That research did not uncover any evidence that the laptop documents were forged. In 2005, ISIS criticized the use of these documents to establish that Iran had an on-going nuclear weapons effort. Likewise, ISIS criticized those who confused work on re-entry vehicles with actual work on the nuclear warhead that would go inside the re-entry vehicle, as the documents make no mention of a nuclear warhead.
At the request of one author, ISIS reviewed a draft article purporting to show that the documents are forgeries. After checking several of the claims and discussing the results of our review with this author, ISIS determined that this article’s central conclusion was not substantiated by the evidence presented by the author. He subsequently published this article without addressing ISIS’s central criticisms.