PolyMet says environmental improvements made to copper-nickel mine project

-- The company planning the first proposed copper-nickel mine in northern Minnesota says it has made several environmental improvements to the project. PolyMet is planning an open pit copper-nickel mine near Babbitt, with a processing facility in Hoyt Lakes.

The company is working on a draft supplemental environmental impact statement due out this summer, after the EPA sharply criticized the original 2009 draft.

PolyMet spokeswoman LaTisha Gietzen said the company will capture water released from waste rock piles and the tailings basin to meet the state's strict sulfate standard to protect wild rice.

"One of the things we're doing is putting in this in-ground containment system, basically a cutoff wall, or an underground dam, that keeps groundwater and surface water from leaving the area," Gietzen said.

The water would then be reused at the facility or treated with reverse osmosis before it's discharged.

Kathryn Hoffman, staff attorney with the Minnesota Center for Environmental Advocacy, says she is skeptical PolyMet could capture the vast majority of water seepage.

"We're looking at a potential situation here where the state of Minnesota may have a site that requires a very expensive form of water treatment into perpetuity," Hoffman said.

Editor's note: This story has been revised from the original to state that the goal of a ground containment system is to meet the state standard for sulfate in waters that produce wild rice, rather than preventing sulfuric acid runoff.