The verification regime that is described in the Joint Comprehensive Plan of Agreement (JCPOA) is stronger than any that have been applied to countries that have not been defeated in war. It applies to all facets of the Iranian nuclear program. One of the possible paths to a bomb would be through Iran’s uranium enrichment program. The verification regime covers uranium processing from the mine through centrifuge manufacture and use. The International Atomic Energy Agency (IAEA) will monitor the verification provisions (Preamble, x).
Iran has promised, “for 15 years or longer,” to make the necessary arrangements for a long-term IAEA presence, including issuing long-term visas and providing proper working space at nuclear sites. The number of designated IAEA inspectors will increase to 130-150, and is to allow the designation of inspectors from nations that have diplomatic relations with Iran (Annex I, N.67.2-3). Because the United States does not have diplomatic relations with Iran, it’s likely that none of the inspectors will be American. But Americans working for the IAEA may still have a role outside of Iran.
I like to think in terms of material balances: uranium in must equal uranium out. In this case, that means that the amount of uranium coming out of the mine must equal the uranium that comes out of the centrifuges. As the uranium moves through this processing, it starts as oxide, is transformed to hexafluoride, and then back to a different kind of oxide.
Let’s look at uranium flow, starting from the mine.
For 25 years, all uranium ore concentrate produced in Iran or obtained from any other source will be monitored by the IAEA to make sure it is transferred to the existing uranium conversion facility (UCF) in Esfahan or another facility that might be built in Iran in the future. Iran will provide all the information the IAEA needs to verify the inventory of uranium ore produced (Annex I, Section O).
The Additional Protocol and Iran’s Safeguards Agreement with the IAEA cover facilities like the UCF. The IAEA has been monitoring amounts of uranium going into and coming out of the UCF and will continue to do so. Section L of Annex I says that Iran will provisionally apply the Additional Protocol and will seek its ratification by the President and Parliament. Because Iran signed its Additional Protocol in 2003 and then suspended ratification, there is a question as to whether it will be ratified this time around.
The UCF converts the uranium ore concentrate to UF6 for enrichment. Iran’s centrifuges at Natanz Fuel Enrichment Plant (FEP) will continue to be used for enrichment and will be the only way Iran can enrich uranium. Annex I, Section S specifies that for 10 years, Iran’s research on uranium enrichment will include gaseous centrifuge technology only. Not laser isotope separation, electromagnetic isotope separation, chemical exchange, gaseous diffusion, vortex and aerodynamic methods, or anything else. Iran will permit IAEA access to verify that it is not working on any of these methods.
Only 5060 centrifuges are allowed at the FEP for enriching uranium (Nuclear A.2). Iran will permit the use of on-line enrichment measurement and electronic seals that communicate their status to IAEA inspectors, along with other IAEA-approved technologies (Annex I, N.67.1), which probably include video cameras (already in use) and radio frequency identification (RFID) markers. Here’s a video overview of some of the IAEA’s surveillance technologies. Iran commits for 15 years to allow the IAEA regular access, up to daily if requested by the IAEA, to all parts of the FEP and the Pilot Fuel Enrichment Plant (PFEP), a part of the FEP (Annex I, P.71).
Centrifuges and their infrastructure will be removed from the FEP and stored in Hall B under continuous IAEA monitoring. Iran will permit IAEA monitoring for 15 years to verify that this equipment remains in storage and is used only to replace failed or damaged centrifuges (Annex I, P.70). The IAEA will confirm the failed or damaged status of centrifuge machines before they are replaced (Annex I, F.30). Infrastructure includes UF6 pipework including sub headers, valves and pressure transducers at cascade level, and frequency inverters, and UF6 withdrawal equipment from one of the withdrawal stations, which is currently not in service, including its vacuum pumps and chemical traps (Annex 1, F.29). That’s everything that makes a centrifuge work.
Research on more advanced centrifuge models will be done at the PFEP. Centrifuges now in the PFEP will be removed and stored in Hall B under IAEA monitoring. Because I’m looking at a uranium materials balance, I’ll leave out which advanced models are allowed. One relevant point: pipework on the IR-6 and IR-8 centrifuges will be welded in place to combine enriched and depleted output streams and verified by the IAEA (Annex I, G.33,34). That means that the product will have the same composition as the starting material: no net enrichment.
At Fordow, all centrifuges beyond the allowed 1044 (JCPOA, A.6) and all UF6 infrastructure will be removed and stored under IAEA monitoring. (Annex I, H.46). For 15 years Iran will permit the IAEA regular access in order to monitor that the centrifuges in use are enriching only stable isotopes and that undeclared nuclear material is absent (Annex I, H.51).
The uranium in and out of the centrifuges at Natanz and its isotopic content will be monitored by the IAEA under Iran’s Safeguards Agreement and the Additional Protocol, as it is now. Iran will keep enrichment levels below 3.67%, and the total amount of uranium enriched to 3.67% will be less than 300 kilograms (Nuclear, A.5-7). I hope to make this limit the subject of another post.
Iran will submit a plan for long-term enrichment and for enrichment R&D as part of its obligations under the Additional Protocol. The IAEA will confirm annually that Iran’s activities are in line with this plan (Annex I, I.52).
Because centrifuges are an essential part of the uranium route to a bomb, Section R of Annex I specifies how the IAEA will monitor facilities that could manufacture their most sensitive components, the rotor tubes and bellows. Iran will also provide an initial inventory of all existing centrifuge rotor tubes and bellows and will continue to report on changes in that inventory. The IAEA will verify the inventory by counting and numbering existing and new rotor tubes and bellows and will monitor the facilities for 20 years (JCPOA, C.15). Iran will also declare all locations where rotor tubes and bellows are produced, and all equipment used for production. The IAEA will continuously monitor production equipment to make sure that it is being used only for activities specified in the JCPOA.
I take this to mean that the IAEA will be allowed to install video cameras in the production facilities and RFID chips on equipment, along with other monitoring equipment they may find useful, like electronic seals that transmit their status.
There is a continuous chain of monitoring from when the ore concentrate leaves the mine to when the enriched (only to 3.67%) uranium leaves the centrifuges. Unallowed additions or diversions will be seen. In order to develop a uranium-based nuclear weapon, Iran would have to build a parallel supply chain including a mine and mill, a conversion facility, and centrifuge manufacturing and use. One or more of these components would be detected.