[sephamorr]

Something that's usually missed about nuclear waste is that the most radioactive wastes have the shortest half lives so burn themselves out quickly. The waste that lasts for thousands of years is far less radioactive. For example, in a uranium mine, you don't even care about the dose you get from uranium (~4 billion year half life), but you do care about the fission products with far shorter half lives. Your point stands though.

[verall]

But some of these have medium half-lives have decay sequence through many materials with very short half-life. So even a small amount of decay from the medium-life material can then release a lot of radiation; enough that the original material is extremely dangerous.