

before the mine gets filled back in.
That has to be prevented from happening, and those mines have pumps in them. Otherwise land around gets poisoned (and also eroded).
So putting useful objects inside those mines at least makes them not just passive expense.
If someone wants to know what if you just don’t pump the water out of an unused mine, leaving it be, then they can read what happens in Donbass now that nobody takes care of those many depleted mines there, due to war. It’s like Mordor basically.
Well, if it is a bubble (at least the centralization part, not the “AI” part), then they are building locations with plenty of energy and water connected. Can help with re-industrialization a bit later.