Thread by @ArmsControlWonk

This is probably the the new North Korean uranium enrichment facility that @iaeaorg DG @rafaelmgrossi briefed the Board of Governors about. @sam_lair and I have a summary on the blog. Nice shot by our friends at @planet.
armscontrolwonk.com/archive/122048…

Here is what @grossi said:
iaea.org/newscenter/sta…

The dimensions, layout and other features do resemble the Kangson UEP when it was constructed. Here is a 2002 image of the Kangson under construction -- the central enrichment hall is about 93 m long, which is the right length for two 164-centifuge cascades end-to-end.

You remember the Kangson Uranium Enrichment Plant, surely. (Good times with @DaveSchmerler and @nktpnd.)
thediplomat.com/2018/07/exclus…

That's the same set up as the first two enrichment halls at Yongbyon, as well as the early enrichment halls at Kahuta in Pakistan. Pakistan's AQ Khan was, of course, an important source of assistance to North Korea's centrifuge program (as well as others) in the 1990s.

The big question is how many centrifuges will it hold? If the new facility is a copy of the OG hall at Kangson -- and it is about the same size -- the new facility might hold ~24 cascades or 3,936 centrifuges. At 4 kg per machine, that's ~15,744 kg SWU or 73 kg of HEU a year.

However, North Korea has been squeezing more and more centrifuges into the smaller spaces in recent years. We really saw that when Kim visited the Kangson and Yongbyon UEPs. Here's a table showing the meters per centrifuge at different facilities and the meters per cascade width.

All the above estimates on numbers come from looking at the pictures, geolocating and then measuring the buildings in satellite images. You get the idea.

If North Korea squeezes in 28 or even 32 cascades, which is not impossible given other places we've seen, then the number could be a lot higher -- 3,936-4,592
5,248 centrigues or 85-98 kg of HEU a year.

I'd probably guess 28 cascades or 4,592 machines if I had to, but we won't really know unless Kim Jong Un decides to visit. Which, given the way things have been going lately, seems more likely than not.

How many bombs is 73, 85 or 98 kg of HEU? I hoped you wouldn't ask me that! The @iaea "significant quantity" is 25 kg of HEU. The Iraqi design used ~15 kg of HEU. Pakistan probably does better than that. Tom Cochran thinks the number should be 3 kg.
ambienteparco.it/pdf/fissionwea…

The question probably isn't worth answering, anyway, since North Korea likely uses composite pits, which would layer both Pu and HEU, has a mix of fission and staged thermonuclear weapons. So, a lot depends on what kind of arsenal one assumes they are building.

*One of the above posts was to read: "If North Korea squeezes in 28 or even 32 cascades, which is not impossible given other places we've seen, then the number could be a lot higher than 3,936 -- 4,592 or 5,248 centrifuges/85 or 98 kg of HEU a year."