In a first of its kind three day public hearing this week, the U.S. Army Corps of Engineers is hearing testimony to determine whether the proposed PolyMet copper-nickel mine would violate the water quality standards of the Fond du Lac Band of Lake Superior Chippewa, whose reservation lies downstream of the proposed project. 

This is a morning update from MPR News, hosted by Cathy Wurzer. Music by Gary Meister.