[lstodd]

Just dump it on the South Pole.

It'll get frozen under hundreds of meters of ice (very good radiation absorber, plus a natural heat sink) and begin a hundred million year voyage to the sea. At which point it won't be radioactive any more and will get transported and dumped into deep ocean by the icebergs.

[petschge]

Water is a very good neutron reflector and moderator so it is exactly what you do NOT want around your nuclear waste. Also metal containers tend to rust when there is water around. The low temperature in the ice will slow that down a bit, but will not prevent it.

Remember: while there are problems that are solve after smart people have stared at the problem for decades, there are many more occasions where all you can come up with is ideas that have been considered and found impracticable all long time ago and you just don't know enough about the problem to see why your idea wont work.

[lstodd]

You sound like it's now forbidden to joke on the internets.

Besides, when one buries some mildly radioactive materials in 20 meters of ice with a median temperature of 230K or something like that, it just doesn't matter what neutron flux they release. And if they heat up, they would just sink deeper.

What matters is that that the neutron flux is adequately dissipated. Which it would be.

[SubiculumCode]

From my understanding, clay containers are preferred for nuclear waste.