Reader's View: Only problematic outcomes with tailings
This is regarding the Aug. 28 story, "The dam debate: PolyMet tailings basin dams are key point in upcoming permits." It reported that, "Much of the waste rock will be as small as grains of beach sand. In theory, the stuff will settle into the basin, and, as more is pumped in, the dams will be raised in steps, 20 feet at a time, over the 20-year life of the (mining permit)."
But we cannot predict the movement of increasingly shifting earth. I believe containment is a fairy tale told by those who wish to profit at any cost to all of us living, walking, swimming, crawling, flying, and rooted beings.
Minnesota narrowly has averted disaster in the last few years from tailings. In 2012, a 1,000-foot crack developed overnight in the Hibbing Taconite dam, requiring emergency buttressing. In 2013 and 2014, Minorca mine released tailings when a pipeline and dam partially failed. In 2000, a tailings pipeline spilled tailings from the Northshore mine into the Beaver River for over a day before it was discovered, requiring extensive cleanup.
The reuse of an old, leaking tailings basin is important to understand fully, not partially, as reported. If PolyMet actually collects, and returns to the tailings basin, the contaminated surface water and groundwater seepage from sulfide ore processing, the company will reduce the stability of the dam — since it won't be leaking as designed.
Once there are sulfide ore tailings, there are two problematic outcomes: Either it leaks and contaminates surface water and groundwater or the contaminated water is captured and put back in the tailings basin, making the basin more unstable.
The word "will" when reading about PolyMet's proposals needs to be changed to "may" or "might."
As of Feb. 27, 2014, there were 1,322 Superfund environmental cleanup sites in the United States; 53 additional sites have been proposed for entry.