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Water or sulfide mining: Which is more valuable?

Sulfide mining has frequently contaminated both groundwater and surface-water resources with acid drainage and heavy-metal leaching.

The commodity value of water in northeastern Minnesota exceeds the commodity value of PolyMet’s copper-nickel ore.

When evaluating the impact of the proposed copper-nickel mines like PolyMet and Twin Metals on the natural resources of Minnesota, regulators, political leaders, and the public should consider the value of water as a natural, replenished resource.

The target of copper-nickel mining companies is an ore formation called the Duluth Complex, which lies in the middle of some of most beautiful and enjoyable lakes, streams and forests in the world. The problem with the proposed mining is that these ores are embedded in sulfide rocks. Unfortunately, the process of mining and recovering metals from sulfide ore has a long and sordid history of water pollution.

PolyMet is a Canadian company, with a “strategic partner,” Glencore AG, a Switzerland-based multinational corporation engaged in mining and commodities trading. Glencore has invested $118 million into PolyMet. PolyMet, in exchange, has agreed to sell all of the copper concentrate the mine would produce to Glencore for five years if the mine is permitted. Glencore, separately, has agreed to sell Chinese firms copper concentrate at market rates for the next eight years. Any profits made by PolyMet will flow to destinations far from Minnesota. 

A good trade?

Using PolyMet’s own numbers, they stand to earn over $4 billion over the 20-year lifespan of the project, if no reclamation costs are included. Let’s assume that such rosy projections are accurate. Would that be a good trade if we considered the economic value of the water resources that are at stake from PolyMet and sulfide mining proposals that could follow?

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Sulfide mining has frequently contaminated both groundwater and surface water resources with acid drainage and heavy-metal leaching. And a review [PDF] of environmental-impact statements for mining projects nationwide by EARTHWORKS shows that while companies and regulators never predict water pollution in the planning stage, nearly all sulfide mines end up contaminating water.  

Water is the dominant natural resource in northeast Minnesota. Without even considering the tourism and recreational value of all of these lakes and rivers, the raw commodity value at stake suggests we should think twice before threatening this resource. In southern California, the wholesale value of drinking water is $1,300 per acre-foot. Water is even more valuable elsewhere. In drought-wracked Central Texas, water from the Edwards Aquifer is valued at over $5,000 per acre-foot.

The commodity value of water in northeastern Minnesota exceeds the commodity value of PolyMet’s copper-nickel ore. One might object and say that not all of this water is at risk, which is true, in a limited sense. But the choices Minnesota makes about PolyMet are really decisions about inviting the sulfide mining industry in to our water-rich state.

Value of water will rise

When one considers the rapidly depleting Oglala Aquifer, growing droughts, and climate change, the value of water can only increase. And yet, we’re seriously considering taking on an industry that promises 500 years of water pollution? That’s foolish.

So, why mine and take the chance of destroying such a rich natural resource, the industries it supports, the value of lake property, and the tax base? This is a case where the minerals are more valuable staying right where they are. The real strategic resource that Minnesota possesses is our water. 

Clint Jurgens is a retired high-tech engineer and entrepreneur. Mary Ann Jurgens is a retired writer. They own a home on White Iron Lake.


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