why don't they dump nuclear waste into space?

Answer 1

This would be a terrible idea.
1) First of all, it would be horribly unsafe. Even the safest 'man-rated' rocket boosters have a failure rate of 1/1000. That is nowhere nearly a safe enough ratio for moving hundreds of tons of Highly Radioactive wastes into even a Solar orbit.
2) You say 'space' like that is the end of it. Orbit around the earth? Orbits, even Clarke orbits decay, and here comes the waste back. Solar orbits? These also need to be carefully calcualted to prevent a future mishap or collison. Interstellar space? I'm sure that that would be a nice friendly gift for any other life forms out there, our waste?
3) This would be fabuolosly expensive. Currently it costs about US $10,000 a pound to send something to high orbit.
4) It is unnecessary to do this. We have proven technologies for 'filtering' or reprocessing wastes to recover fissionable materials for re-use in reactor cores. We have technologies for using wastes themselves to generate power and more fuel (Breeder reactors). Baisically the stumbling block is no one wants these facilities in their neighborhood and the failure of our politicians to address these problems in a logical and scientifically sound strategy.

Answer 2

It was considered by many engineers and scientists. There are a few main issues with that.

1. cost
2. danger

Nuclear fuel is heavy. It will cost a lot to send it up there. It is a lot cheaper to develop and store in a safe place.

The second issue is one that is of greatest concern though. If there were to be an accident such as the rocket exploding mid-air, it would release huge amounts of waste into the atmosphere. This is the danger that keeps us from doing so.

Answer 3

The risk of an accidental explosion before exiting the atmosphere renders that option as impractical....it'd be close to global suicide Russian roulette style....