K-25

Quiz question - what was the most expensive part of the Manhattan project?

Okay, so a title K-25 is a little bit of a giveaway, but  K-25 was the single most expensive project of the Manhattan project .  I think that makes an excellent example of why the nuclear safeguards need to be material based, not weapons design.  It simply cost much more to get the material then to have a workable design.

I also never realized how big K-25 was (now most of it is torn down - there was some effort to leave a corner of it up, but I don't think any thing became of it). It was once the biggest building in the world, but I found this to be really helpful.  Go ahead and put it over your favorite neighborhood.  And to think about how far enrichment technology has come that you can hide it in a little facility in Iran*.

Current US Enrichment with K-25 overlaid using the above link. The Paducah plant is around 75 acres, while K-25 was around 46 acres.

It might be a little deceptive to put K-25 next to Paduch as K-25 was only part of the enrichment process (breeding at Handford, calutrons at Y-12). Also, what's with the DOE giving boring building names?

*One of the arguments against the laser enrichment is that it will make it too easy to enrich material for rouge actors.