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, watching the expansion of open pits and piles of waste rock that we call "dumps." As kids growing up, we never questioned that men worked to mine the iron that was made into steel and turned into cars. As a young teacher on the Iron Range, I never questioned how taconite mining was done, or what it would do to the land.  


When the natural ores were depleted, a process was developed to blast, crush and grind 

 rock containing 25 percent iron into pellets. It's only now, 50 years later, that we are beginning to realize the extent to which taconite mining has disrupted the land with open pits, waste rock piles, tailings basins and surrounding dikes that will be unusable when mining ends.  It's only after 

our fish have become contaminated with mercury

, when haze has become visible as one drives  toward the Range, and when our human population suffers from increasing allergies, asthma and lung disease, that we realize there is pollution in our water and our air.


Recently, market demand from China and India created a new wave of mineral exploration in Minnesota's Arrowhead Region. The 

 of low grade sulfide mineralization, including less than 1 percent copper and nickel, and ounces per ton of platinum, palladium and gold, is advertised as one of the largest undeveloped metal deposits on earth.  


If it sounds too good to be true, it is. This low grade mineralization would result in the mining of 99 percent waste rock. It would come at the expense of forests, wetlands, watersheds -- and, ultimately, the 


New technology, such as hydrometallurgy, enables companies like 

 to make a profit mining low grade metals--provided that the price of the metals remains high. Toxic residues from the hydromet process, resulting as metals are leached and precipitated from their ores, would be placed in lined tailings cells, eventually leaking into the ground water. 


In a sulfide ore deposit, all of the metals are bonded to sulfur. Acid mine drainage occurs when rock is excavated, crushed and ground, and the sulfur is exposed to air and water, forming sulfuric acid. This sulfuric acid leaches out heavy metals that remain in waste rock piles, tailings and pit walls. This process can continue for hundreds to thousands of years -- until all the sulfur and metals are depleted.  Because mining less than 1 percent ores results in 99 percent waste rock, there is huge potential for acid mine drainage. The EPA acknowledged this potential when it rated the draft environmental impact statement for PolyMet's proposed copper-nickel mine as 


The metallic sulfide ores of the Duluth Complex lie under what is now Superior National Forest --adjacent to the BWCAW. This is an area of forests, rivers and wetlands. This water-rich environment makes acid mine drainage more problematic -- both fueling the process, and distributing the acid-metal load downstream. The destruction of wetlands releases carbon into the air, and removes a source of carbon sequestration. 


Is it wise to mine low grade deposits of sulfide ores in a water-rich environment because this is where they happen to be? Are we prepared to mine increasingly low-grade ore in any environment just because we have the technology to do so?


Is it wise to destroy what is left of our natural environment because conditions might be worse in some other country? If permitted, PolyMet would likely be purchased by a mining conglomerate. These companies mine on a global level. So why aren't they mining responsibly everywhere?

 
Are we promoting mining out of fear?  Are we afraid that without these metals we will not be able to have our computers, our cell phones, our TVs?  Has anyone seen any shortages on the shelves?


What evidence do we have that it is in the best interest of northeast Minnesota to allow Canadian companies to mine our metals and send them abroad, leaving behind land that will be unavailable for tourism, recreation, real estate or forestry,  and water that will be unsuitable for fishing or drinking?


New mining in northeast Minnesota means digging up new land--that of the Arrowhead.  What legacy does this "next generation" mining hold for the next generation?

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Elanne Palcich

Author

Too often in the past, questions have gone unasked. The environment suffers as a result.

Before mining in northeastern Minnesota, dig up some answers

Go Deeper.

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