Iran’s key nuclear sites have not suffered any further damage since Friday, the first day of Israel’s attack on the country, the head of the International Atomic Energy Agency (IAEA) announced at a governors meeting on Monday.
Rafael Grossi, the director general of the nuclear watchdog, said while buildings above ground at Iran’s principal uranium enrichment site at Natanz had been destroyed, strategic locations underground had not been struck.
“There has been no additional damage at the Natanz fuel enrichment plant site since the Friday attack,” Grossi said. “There has been no indication of a physical attack on the underground cascade hall containing part of the pilot fuel enrichment plant and the main fuel enrichment plant.”
That contrasts with claims made by Israel’s military on Friday after its air force bombed the Nantaz site which said, “the underground area of the site was damaged”.
A second Iranian enrichment site, at Fordow, which is hidden 80 to 90 metres below a mountain, is not thought to have been impacted, Grossi said in the update, though it had been attacked by Israel on Friday evening. “No damage has been seen,” the director general said.
Israel launched its attack on Iran on Friday to pre-empt a secret Iranian programme to build a nuclear bomb, Israel’s prime minister Benjamin Netanyahu said, which would require uranium to be enriched to 90% to produce a warhead.
The country runs two principal enrichment sites, at Natanz and Fordow, and has already accumulated 408.6kg of 60%-enriched uranium – enough, the regulator said last week, to make nine nuclear bombs if the enrichment continued.
There are two facilities at Natanz. The main site, the fuel enrichment plant, is estimated to be between 8 and 12 metres below ground. Military analysts believe it can withstand bombing with all but the heaviest weapons available to Israel, and to destroy it would likely require multiple strikes with the 1.8-tonne Rocks missile or 1.6-tonne Air Lora missiles.
A lesser site, the pilot fuel enrichment plant, was based partly overground and vulnerable to attack. Satellite imagery confirms there is serious damage to buildings overground, including the pilot fuel enrichment plant – but it is not possible to assess the impact to the underground hall from the imagery above.
Electricity infrastructure – a sub-station and power supplies had also been destroyed at the Natanz site, Grossi said, which is also confirmed by satellite imagery – and the resulting “loss of power to the cascade hall may have damaged the centrifuges there”.
Naturally occurring uranium contains only 0.7% of the fissile isotope, uranium 235. It has to be enriched to 90% uranium 235 before it can be used in a warhead. Uranium is converted into a gas, uranium hexaflouride, and spun in centrifuges to separate the uranium-235 from the heavier, stable uranium-238.
There was also “both radiological and chemical contamination,” at the Natanz site which could potentially include a dangerous uranium leak. Speculating, Grossi said, “it is possible that uranium isotopes” are “dispersed inside the facility”.
If so, the radiation would primarily consist of alpha particles that would pose “a significant danger if uranium is inhaled or ingested” – but the the IAEA chief said this risk could be effectively managed with respiratory devices or other protective measures.
Iran’s second enrichment site Fordow is generally considered to have been built so deep below ground that it could only be destroyed by US GBU 57/B bunker buster bombs, which are so heavy they can only be launched from B-2 bombers.
Some other Iranian nuclear sites, such as the Bushehr civil nuclear reactor, had not been attacked, the IAEA said. Four buildings were damaged at a research site at Isfahan, including a central chemical laboratory and a uranium conversion plant, it added.