This link. Said better than excerpting could suggest. Read it all there.
On the environmental impact anticipation of Polymet and following larger scale non-ferrous mining; Sorensen links to Aaron Brown's item at Strib, "Canadian mine disaster raises tough questions about Minnesota nonferrous mines." online here. Follow that one on your own too, readers (although Sorensen does some excerpting).
Abeler's rhetoric is more tame than McFaddens, and sticks closer to facts.