[gambiting]

I mean, if there is a geological process that can bring stuff up from 6km depth then we're all dead anyway - the layer of impermeable rock above it is not called that for no reason. And with the half life of some of the elements in the waste as long as 100k years yes, it's ideal if it's buried and forgotten where no one can get to it. Irresponsible is storing this stuff on the surface - if the civilization collapses and no one is there to look after these containers they pose mortal danger to anyone finding them even in thousands of years. But no one is in danger from stuff quarter of the way from the Earth's mantle.

[Krasnol]

The irony here is that you already propose to disturb this layer. Even though the technology is pretty new. Despite that you already not only want to penetrate this layer, you want to drop radioactive waste in there.

Btw what about Countries like Japan. They can't do that for obvious reasons. Will the US take this waste? I mean, they will keep producing it. And what about the next country that comes along. I'm sure they can pay good because it won't be every country that can afford this procedure. What about the former soviet republics (currently already used as dump by France for example)? They can't afford that. Will the US take that too or will they pay for it? Maybe the EU because they are closer and are more afraid?

And yes I agree with you that it's irresponsible to store that on the surface. It's even more irresponsible to produce even more of it. But hiding it away in the hope that some later generation in the future will still remember where it is and not touch it, not do anything to the terrain around it or dig it up to misuse it is not only naive, it lacks imagination. You should read more SciFi. It teaches you to think in time frames that are relevant here. Looking back at our own short history may help also.

[gambiting]

But....we already do penetrate it, routinely. Oil and gas fields are below it more often than not. Punching a 50cm hole in impermeable rock does nothing to it.

As for other countries - again, just because Japan cannot do it doesn't mean we shouldn't be doing this altogether. They can store their waste on the surface until we come up with a better plan. But countries like US can, and US has enough nuclear waste to fill 800 of these boreholes already - it's definitely worth doing for them, even if Japan can't. The answer to your question would be ultimately political, and yes, I imagine Japan would pay someone else to have it disposed of. But that's just a guess.

And I do read a lot of Sci-Fi, thank you for your concern. I just don't think you realize what sort of depths we are talking about - there is no geological process bringing material up from these depths to the surface. When we dig to that depth we literally find material buried for millions of years. You'd be talking about rupturing of the Earth to a point where a new mountain range rivaling the Alps would be created - and if that happens then like I said - we're all dead anyway.

As for the lack of imagination - quite the contrary! The mantle in the shallowest spot is only 7km below the surface - and the temperatures there can be as high as 4000C. That's enough to melt nuclear fuel, in which case it would just become part of the Earths crust forever - and it's not like you're polluting the Earth with filthy waste that someone might dig up at some point - the composition of the Earth at that point is already radioactive itself, dropping our nuclear waste into it is not just a proverbial but a literal drop in the ocean. Just like sending this stuff into the sun doesn't make the sun any worse off - the Earth's mantle is already an extremely dangerous place where no Sci-Fi would even suggest digging or future human activity of any kind. In that sense it's a good place for our most dangerous waste, since putting it there doesn't really make it any worse off.

And finally - as you noticed, whatever we do is irresponsible. In my mind, keeping it as we do right now is more irresponsible than burrying it in a way that makes it completely safe even if a comet struck our planet and civilization was completely wiped out. Whoever survives that won't accidentally run into steel containers full of death pebbles. And if civilization emerges that is somehow capable of not only digging but also retrieving material from close to the Earth's mantle, then that civilisation will understand what radioactivity is - no one will ever dig this stuff out "by accident". It's just the sensible option right now, while keeping it around isn't.