This is an elevator to move mine car loads of sand to the surface for cleaning and eventually glass production. Below is a flooded equipment vault. In front and behind is a loop through the larger tunnels in the mine. The horizontal braces supported electric cables for the mine carts.
There’s concrete under that dirt… under that water… somewhere.
Days after the long-flooded basement was pumped out. Note the water lines!
Water at the bottom of the silo was perfectly clear.
A broken roof drain turned the fourth floor into a skating rink. Frost covers every surface. Kodak Portra 400 in Voigtlander Bessa.
The orange bars were secured to the tunnel walls to support electric lines for the mine carts. Lower parts of the sand mines were allowed to flood. The water was perfectly still, and made for a mud so thick it could suck off your boots.
Short-stack remains of mounts for rod and ball mills, if I was to bet. The concentrator separated junk rock (tails) from the copper and silver ore, to such a point it could be smelted.
This picture shows the challenges of moving around underground in the base.