The nuclear spike deterrent field has been a favorite of mine

I watched a documentary about that: Into Eternity

What I thought was interesting about the film was the balance between entertaining a fantastical vision of some future explorer stumbling across the radioactive site, and the mundanity of most of the actual work.

One of the engineers said something like: "When we seal this up with so much concrete, there's no way you're getting in here without machinery. We should be more concerned about a future civilization that comes back here for radioactive materials when they've exhausted all other natural sources"

And then there's a whole section of the film about rules-lawyering the storage site. The dump was chartered by the Finish government to seal waste "for all time", and the engineers were mad that nothing is truly permanent.

Man this would be such a killer start or premise for a sci fi book

This place is a message... and part of a system of messages... pay attention to it!

Sending this message was important to us. We considered ourselves to be a powerful culture. This place is not a place of honor... no highly esteemed deed is commemorated here... nothing valued is here.

What is here was dangerous and repulsive to us. This message is a warning about danger. The danger is in a particular location... it increases towards a center... the center of danger is here... of a particular size and shape, and below us.

The danger is still present, in your time, as it was in ours.

The danger is to the body, and it can kill. The form of the danger is an emanation of energy.

The danger is unleashed only if you substantially disturb this place physically. This place is best shunned and left uninhabited.

Yeah iirc the absolute best solution proposed was to not put any markings at all and bury it deep enough that any future civilization advanced enough to get to it will probably realize what it is long before they actually get to it.

I was thinking about this and their thinking was way too complicated. The symbol you need is bones. Bones are always associated with death and decay because after death, bones are the thing that's left.

And yes I know they thought of it but I think their dismissal of it is wrong. Their counter argument that it was once a symbol of something else by some culture, therefore. But again by its very nature it's associated with death. Any society capable of this excavation is also capable of thinking "hmm what did they mean? outside of our own culture of course" and will quickly figure out it's bad.

Is this loss?

Made from dead plants, rather.

Or you could hit these yellow rocks together and become death itself.

They sacrificed their lives so we could know both the power and danger ofthee subatomic world. They are accidental heroes. Now, someone who did that shit today with full knowledge of the consequences - they would be batshit insane.

https://en.wikipedia.org/wiki/Demon_core