There are three huge mines south of Tucson, and I have toured the Asarco mine, the only one that has tours. The mines are west of I-19. Twin Buttes, owned by Freeport-McMoRan was closed in 2010 but may reopen.
Freeport owns the Sierrita mine which is next to Twin Buttes.
All are open pit mines with miles of trailing piles.
I think the board should be open for discussion on all copper mines in Arizona.