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Cheryl Rofer worked on projects involving uranium chemistry, nuclear fuel cycle, and national security issues at the Los Alamos National Laboratory. She now writes at Nuclear Diner and on Twitter at @cherylrofer.

The news is full of negotiating positions and silver-bullet solutions to resolve the Iran negotiations. But what, exactly, is Iran's current nuclear status?

Iran has been building a nuclear capability for more than a decade. That capability inherently can be used for civilian nuclear power plants or nuclear weapons. Uranium enrichment and a heavy-water reactor at Arak are centerpieces of the program and other nations' concerns. The purpose of the talks is to arrive at a conclusion that allows Iran a peaceful program while assuring against its development of a bomb.

Six months ago, Iran and the P5+1 (United States, Britain, France, Russia, China, and Germany) agreed on a Joint Plan of Action (JPOA) to build confidence that both sides mean what they say. The International Atomic Energy Agency (IAEA) is monitoring the agreement, which ends on July 20 and will likely be extended. Both sides have held to it.

The IAEA's most recent report was on May 23. The negotiators may have more recent information, but the differences are probably small, so I will use its numbers.

Iran's enrichment capacity is at the center of the publicly stated concerns. According to the IAEA report, the numbers of centrifuges have not changed over the past six months. Of the approximately 19,000 centrifuges installed at the Natanz and Fordow plants, only about 9000 are operating. The IAEA has visited centrifuge production and storage facilities and says that there is no stock of centrifuges set away, ready for installation.

Uranium must be processed through two chemical forms to make reactor fuel: UF6 gas, the form needed for enrichment, and uranium oxide powder, for transport from the mine and then for fuel elements. Bombs need uranium metal; Iran has no known processing plant for that transformation.

Iran now holds 8,475 kilograms of 5 per cent U-235 in the form of UF6 gas. Its stock of 20-per-cent-enriched UF6 has been decreased from a high of 447.8 kg to 38.4 kilograms. All of this material could be further enriched, if Iran chose to do so. In the past six months, Iran has continued to enrich uranium to 5 per cent, but has not enriched higher than that.

Most of the 20-per-cent-enriched UF6 has been converted to uranium oxide, some of which has gone into 26 fuel assemblies for the Tehran Research Reactor. Of those, 20 have been transferred to the reactor. Ten are currently in the reactor. It's not uncommon to stockpile fuel elements for this kind of reactor, but a double load in reserve should last another decade or two.

To further enrich that uranium, the fuel elements would have to be disassembled and the uranium chemically converted back to UF6. That would take time, and the processing would be noticed by IAEA inspectors.

Construction of the Arak heavy-water reactor, also known as the IR-40, is at a standstill. Iran has provided information to the IAEA on the design of the reactor, and they have agreed on a safeguards plan. No new test fuel for the reactor has been produced, and hot cell operations that might be used to recover plutonium have been suspended. Both operations are in early development. Iran began producing reactor fuel only a few years ago; much testing of fuel is necessary for any newly designed reactor, and Iran has little experience in that field.

The JPOA says nothing about what the IAEA calls "Possible Military Dimensions (PMD)," but during the negotiations, Iran agreed to make information available on this subject. The IAEA holds (very closely) a number of documents, along with their own observations, that indicate possible investigations into technologies necessary for building nuclear weapons.

Iran is discussing with the IAEA its development of exploding bridgewire (EBW) detonators, which are safer and more controllable than other detonators and are used by other countries in nuclear weapons. Iran says that their EBW detonators are for oilfield applications. Iran has provided materials to the IAEA, and the IAEA has not come to any conclusions yet.

The IAEA was investigating PMD long before the JPOA went into effect and has many more questions. The EBW discussion is a first step, but the IAEA would like a more systematic approach. However, they leave the door open to piecemeal discussions, requesting further information on neutron transport modeling and calculations (how neutrons split atoms – in a reactor or a bomb) and a site visit to Parchin, where explosives experiments may have been done to give information that is useful only for a bomb.

For the past six months, both sides have stuck by their word as expressed in the JPOA. They are closer to an agreement than ever before.