Digging *big* caverns is easy with nukes. With nuclear dampers, it's
easy to decontaminate them, though the tests in Nevad show that
there's not that much to do anyway (most of the really radioactive
stuff gets buried with part of the ceiling collapses into the pool of
molten rock at the bottom of the chamber).
I like this! I'm definitely going to steal it for my current game. Mining hellworlds just got more probable: "dig" your initial site with a nuke in the middle of the most promising region, then send out your boring machines from there. The only evidence of your mine from above would be the barebones landing pads each with it's ingot loading lift (because you're doing basic ore-processing below) and a central, relatively-small elevator for use by sophonts and perishable imports.
You could even "dig" the same sort of initial site on a large asteroid - boost it up to 1 G before you set off the nuke, then flip and decelerate it once the temporary "floor" cools off.
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