In NE Minnesota there are large deposits of copper and nickel and a few other minerals. However, the state’s environmental appointee (by dimwit Governor Mark Dayton) is determined to stop any mining at all. It’s one reason why the usually liberal voters in NE Minnesota are trending toward conservatives now.
Old saying, “If your enemies are killing each other, get out of the way”. Maybe some of them will have an epiphany and grow a brain?
In sulfide mining, the rejects are 25 percent larger than they were pre mining. This “swell factor” means a huge, above ground pile that won't fit in the pit. It is virtually impossible to bury or cover up the waste.