I do not have a subscription to Scientific American. I saw this article in the checkout lane at the grocer near my home.

The author argues against reprocessing and for storing the waste in casks until an underground repository is ready</snip>

I think this is interesting. If I were a terrorist, I would go after far easier toxics to inflict damage or incite terror. Particularly, I would pursue items that would attract minimal attention in acquisition. Nuclear waste is rather high profile. Home Depot has enough raw materials for a creative terrorist, no? I would think it relatively easy to secure a 200 acre facility to protect the few items of interest on site. This is technical issue.

I also think the processing of radioactive materials into, say, blocks of glass, is an engineering issue; far simpler and less costly than Yucca Mountain, for example. Hanford in eastern Washington has had its issues, but is the issue political, in implementation or outright bad engineering? Even if it is all of these, it must be far less expensive to dilute radioactive materials in glass blocks to the point where they are nearly as radioactive as the ore originally pulled from the Earth than to build a mile deep hole in the ground that has never been filled. A barely radioactive 100kg block of glass is not a tempting item for a terrorist to steal.

I do agree it is a bad idea to leave concentrated materials sitting around in a barrel.