The Uranium Containers
By François Diaz-Maurin has a great catch from Le Monde: an analysis of a satellite photo of a truck near Isfahan carrying what may be the containers of Iran’s highly enriched UF6.
When I wrote my critique of a possible special operation to take the uranium, I had to guess at the containers. Diaz-Maurin gives several possibilities for what is on the truck. One of the possibilities is an overpack weighing 10 tonnes or more.
It’s a very good article, with photos and weight calculations, so go over to the Bulletin of the Atomic Scientists and read it. I’ll add three things.
If the UF6 is in an overpack, then concerns about criticality incidents are largely mitigated. Overpacks will be designed to avoid criticality. An overpack is a large container that can accommodate one or more smaller containers, like the gas bottles I wrote about earlier. It has an internal structure to protect and hold the smaller containers. Nuclear material is often contained several times. The cans for plutonium my team designed were a can inside a can inside a can. For transport, they would likely have been in an overpack about the size of a 50-gallon drum. Perhaps six cans per drum.
If the UF6 is in something as sturdy as those 10-tonne overpacks, it will not be possible to blow it up in any simple way.
The uranium is under a mountain, possibly buried. Iran’s nuclear complex is in no shape to do anything with it. The best thing to do is to leave it until an agreement has been reached on the fighting. [added later]
And I’ll repeat. The closest comparison to such an operation would be Project Sapphire, in which 600 kg of enriched uranium was quietly removed from Kazakhstan. It took a month, with the full cooperation of the Kazakhstani government.
Just so you can see a photo of the truck –