Actually, Wyoming is by far the largest coal producer in the U.S. The mine that they are proposing is a pimple compared to the other surrounding mines. I think it's funny that they are using this project to extract R.E.M.'s from the coal itself. It kind of defeats the purpose of the Trump fantasy of getting rid of all renewable energy and forcing everyone to burn coal to heat their houses.
Again, this comes down to how do they plan on extracting the R.E.M.'s from the coal? Is there a method for this? Maybe in China, but surely not here yet if ever. Ask your bot about extracting rare earth metals. How it affects the surrounding environment and the toll it takes on other natural resources, specifically water supplies. It won't paint a very pretty picture.
That's why we currently send the ore to China to be processed. We are light years behind them facility wise and can't afford to go poisoning aquifers in the west.