30000 year legend

Global warming in recent years has felt like breaking news of big events such as deforestation, shrinking polar ice and endangered polar bears, sinking island of Tepuka(ツバル共和国) and so on. CO2 is considered as the culprit. So everyone, I hope, in the world is frantically trying to reduce the emission of the non-toxic but harmful gas. One of the most effective way to reduce its release is to use atomic energy. It produces far less CO2 in its process when compared with oil / coal fueled thermal electric power plant. Therefore it is the global trend to reevaluate the atomic power plant.
One of the biggest problems with this 50-year-old technology is that it is very "dirty". Instead of CO2, it produces tons of waste and that is extremely dangerous in a way very different from other waste. It is highly radioactive, so much so that you must stay at least kilometers away from it if there's no screen between you and the waste. What do you think they are coping with it? They just reserve it in a highly shielded area within the premise of respective power plants letting them sit and wait for what they call "reprocessing" which is kind of recycling of the waste. But you can recycle only tiny part of it, still worth doing though. Most of the radioactive materials contained in the waste are never gone, only changes their form from solid to liquid. This makes the matter from bad to worse. If it is liquid, it spills or leaks out of the reservoir. This is dangerous indeed in a country with more than a fair share of big earthquakes.
Don't worry, they say. They have come up with an idea on how to treat the liquid. They put the highly radioactive liquid into molten glass to contain it in the solidified glass. It is better than holding it in the form of liquid. It is far easier to handle and there's no worry about spilling or leaking. They say they established the technology.
Then what do they intend to do with the glass that contains fatal amount of radioactive materials? Their plan is to bury it deep under the ground, a few hundred meter deep. How long does it take the glass to become harmless? It is considered 30,000 years.
When I went to the 東京工業大学 culture festival, there was a bus in which they display and explain this burial which they called "geological disposal". I was interested and got in to listen to the explanation. There displayed a model canister (container of the radioactive glass) in the car. I asked to the explainer who seemed quite candid.
"How can you manage this deadliest waste under the ground for 30,000 years?"
"管理することまでは考えておりません"
"How can you make that irresponsible comment?"
"３万年の管理ができると言う方が無責任だと思うのですが。３万年間放っておいても大丈夫にするという思想が現実的ではないでしょうか"
"Ok, so you put a tombstone on the ground above the buried place so that everyone can notice that there buried something dangerous for 30000 years?"
Laughing, he answered "Yes, yes, kind of. And we may have to keep a record at least."
I was a kind of shocked. 30000 years ago we lived in the Stone Age. I do not know what the world will become like in 30000 years. It is possible that people will forget about what was buried under the tombstone. Only a legend that would go something like "Don't get close to that tombstone, or you will be cursed." might remain. Like what we did to the Pyramids, some of us might challenge the legend and try to rob of the grave. When they dig under the tombstone, they would be stopped at a thick concrete wall. Obviously artificial structure. They get excited. They break the wall. What they find under the wall are thousands of shiny metallic containers of the size of a child. They put them on trucks and bring them back home.