The regolith is replete with embedded elements from the solar wind and micrometeorites etc. Most in situ resource extraction would be surface strip mining. But the percentage of the surface needed would be small. Both the moon and mars having no oceans have vast surface areas. A totally exploitive approach would only touch such an infinitesimal tiny portion of the area it’s hard to imagine conservation is a top priority.

Parent was concerned about spoiling pristine regolith by footprints and tracks.

Anyway, multiply the mine areas several times, it's unlikely the raw regolith will be exported. Processing will need solar power plants and radiators to dump waste heat (can't dump it into atmosphere as we're used to).

You could conduct the heat via heat pipes into the crust. The lunar basalt has decent thermal conductivity. Using something like mercury or alcohols (which have a low freezing point, and have ok phase change temperatures), or something more exotic you should be pretty ok. Radiators are mostly useful off a surface that can act like a heat sink, especially one as cold as the moon.

Oh I’d say you wouldn’t process regolith for export at all, but for use on the moon. I think you wouldn’t process and export raw materials on the moon I think you would do heavy industry you wouldn’t do on earth in the cave systems of the moon and export manufacture goods. I don’t think you would even export them to the earth but into orbit or interplanetary. Exported materials from the moon to mars would be a lot more economical than the earth.

If you were to just heat sink underground all the time, it will be a non renewable resource. That already happened in London underground that the ground heated to uncomfortable temperatures over time. But coupled with bidirectional heat pumps and surface radiators, there's heat storage potential.

It is like pristine snow in that it does not have traces of human activity all over it. But in contrast to snow, it changes very slowly, and no weather to smoothen out traces either.