Two hurtles
The first hurtle is finding amounts sufficient to justify the cost of mining. Easy enough. The second is not so easy nor fast in coming: negotiating the swamp of government regulation controlling mining. These areas are likely near or on public lands, making the likelihood of development expensive and in the distant future. I'm not in favor of gutting nature to feed our appetites, but there is such a thing as over-regulation. Hopefully both these possible impediments can be quickly overcome to the satisfaction of all interested parties and for the good of us all. Not too confident of it, though.
