In recent weeks, Iran has dramatically escalated efforts to seal off its cache of near bomb-grade uranium, deliberately collapsing tunnels and booby-trapping entrances with explosive mines, according to five sources familiar with US intelligence.
Getting to the roughly half-a-ton of highly-enriched uranium is now far more difficult, dangerous and time-consuming than it already was just a month ago, when President Donald Trump was publicly signaling that he might order the US military to seize it, the sources said.
The new fortifications by the Iranians add an additional layer of complexity to the Trump administration’s proposed deal with Tehran to remove and destroy its uranium, and the move raises questions about who will take on the dangerous task of digging it out.
What Australia exports is likely Low-Enriched Uranium (LEU), which is less than 20% U²³⁵, and is suitable for nuclear power plants.
Nuclear powered submarines require Highly Enriched Uranium (HEU), which is 20% or more U²³⁵.
Weapons-grade uranium is usually enriched to 90% or higher.
Getting to that 90% level is extremely difficult & time consuming. U²³⁵ and U²³⁸ are chemically identical, so it’s converted to a gas & spun in centrifuges to separate the atoms by weight. Typically hundreds of centrifuges are used in this process. As an example, it took roughly 3 years for the Manhattan Project to refine enough U²³⁵ for the first bomb. That bomb used roughly 60 kilograms of bomb-grade uranium. To get those 60 kg, over 9 metric tons of raw uranium was processed.
It’s this weapons grade uranium that Iran has collected and is protecting.
What’s the “near” in the “near bomb-part uranium” part then? Just a lower ratio of U235?
~80%
Yes, exactly.