system
Given the following post, respond as if you're commenting on Reddit:
human
Would it be possible to pump nuclear waste into a really deep oil field that has run out of oil?

I am completely ignorant of the engineering issues involved, but it seems that liquefying the nuclear waste and then pumping into an empty oil or natural gas field doesn't sound too far away from being possible.

If the oil field is below the water table, does it matter if the nuclear waste seeps down below? In what way could the radioactivity come back up?

If it were possible and multiple nations worked on a single big site, wouldn't this solve the issue of disposing nuclear waste. It would be very expensive, but it could be a long term solution, if the size of the empty space is large enough.
gpt
The problem is more complex than that. For starters though, it wouldn't matter what physical form the waste is in (solid, liquid, primordial ooze) since what we are dealing with are decay products, not physical containment of matter problems. Placing "nuclear" waste (radio actively decaying material or materials contaminated with radioactive substances) requires full containment. The concept you are putting forth assumes that the daughter decay products can not permeate the "pit" left from drilling. This is in fact, not true. As the chain of decay occurs each new decay product must be considered as all waste is not created equal. It may form a lighter more penetrating isotope along its way that will ultimately find its way into the water and or plants in the surrounding area. Having said all this it is best to continue treating waste on an individual basis and plan it's disposal based on its decay chain. In the end high level waste will ultimately be a problem for centuries to come, even with the best of attempts at complete containment.