Despite the hauling and loading of salt, the air isn't uncomfortable to breathe. Vehicles take workers on a sometimes bumpy one-mile drive to the current mining area. Another machine drills holes in the wall. Explosives are placed in the holes and detonated. It is rock salt.
Closer examination shows that it resembles the stuff folks put on their driveways.
Pillars left behind support the mine. None of the salt goes for human consumption. Other mines produce that, in a different way. Workers at the Lyons mine use loading machines to gather the salt. Crushers do their job.