The long half-life [actually the mixture of lengths of half-lives] is really the problem. You've got stuff that's super-hot [fast decay] and so very dangerous mixed with much slower-decaying [so not as dangerous] stuff that needs to be isolated for a super long time. If you run it through a fast reactor/reprocessor, you can use most of the energy and be left with mostly just medium-duration stuff, that will burn out in a reasonable timescale for underground storage, say 1000 years.
We have many dangerous devices extremely close to the population already. Cars kill more people in a year than all nuclear reactors have killed in the whole time of their existence. Should we bury the cars underground instead?
We have many dangerous devices extremely close to the population already. Cars kill more people in a year than all nuclear reactors have killed in the whole time of their existence. Should we bury the cars underground instead?