I quarry on the surface for a few reasons. The main one being my quarries are all solar powered.
I solved the issue of covering them not long ago; I mine out the ocean floor now. Though once this one is torn down I think I'll be done for awhile got a solid supply of everything I need.
Playing: Minecraft, FFXIV, World of Tanks, EvE
Retired from many, incl: WoW: Aesha, Kael'thas; FFXI: Ehlynia, Pandy; Tera: Ehlynia, PvE.