Mining in Wisconsin

A Canadian mining company has an exploratory license and is moving ahead with plans to drill for gold and copper in north-central Wisconsin. Green Light Metals believes the Reef in eastern Marathon County and the Bend deposit in Taylor County have “economic interest” that warrant further exploration.

The company says the Bend deposit, located within the Chequamegon-Nicolet National Forest contains 4 million tons of copper and gold. They say the Reef deposit contains about  454,000 tons of gold reserves. This sounds impressive but it is misleading information. These figures are estimates of the expected available ore and are not the actual amounts of gold and copper that can be realized.

Ore is the rocks that contain the minerals from which a metal is extracted by processing. Gold is bought and sold by the ounce, not the ton. It often takes more than a ton of ore to produce an once of gold. This is true of other metals.

It is difficult to find accurate, current data on how much metal is possible from mineral deposits in Wisconsin. What infromation is available suggest it will be much less than the rosy company figures suggest. One report on the Internet (with no date) was on the Bend deposit and written by geologist Dr. Bill Cordua, University of Wisconsin-River Falls. He says “The deposit’s reserves are estimated at approximately 2.2 million tons yielding 2.77% copper, 0.05 oz of gold and 0.43 oz of silver per ton.”

Mining is a very wasteful, destructive process. Discussing copper mining in general the Environmental Protection Agency says,“The amount of marketable copper produced is small compared to the original material mined. Several hundred metric tons of ore must be handled for each metric ton of copper metal produced, thus generating large waste quantities.” This includes radioactive waste (

The Wisconsin Sierra Club agrees. They point out mining involves multiple stages of extracting and purifying the target metals. For some mining operations all this produces 99% waste byproduct (often toxic) to gain 1% in usable metal.

The consensus of public geological reports I found on the Internet indicated that over the years some 20-35 sites in Wisconsin had been identified as having various metals but none of them in concentrations to be economically viable. One report was by the University Extension (Metallic mineral deposits, Wisconsin Geological and Natural History Survey

The Sierra Club says these inconvenient facts show mining will not be an economic bonanza for northern Wisconsin. The poor, low grade deposits and fluctuating metal prices will only create boom-and-bust short term jobs at best. The waste, pollution, and damage to other economic activity will not be worth the long term clean up costs. We need metals but recycling and mining land fills has more potential than mining low grade deposits. They say landfills often have far higher concentrations of metals than underground ores. For a good short read on mining in Wisconsin go to The Sierra Clubs web article “Metallic Sulfide Mining” at .

Copper and gold mining in Wisconsin is called sulfide mining. The ores contain sulfide which will result in unavoidable toxic waste and water pollution. When sulfide ores are exposed to oxygen, it produces sulfuric acid and heavy metal contaminated runoff. This is inherent to mining and essentially impossible, or economically unfeasible, to prevent or mitigate. ALL MINING OF THESE ORES HAS CREATED LONG LASTING POLLUTION. Mining done by the Romans 2000 years ago is still leaching toxins.

Wisconsin used to have strong mining laws. Wisconsin had a “prove it first” mining law especially targeted at sulfide mining. The law was passed under Republican Governor Thompson in 1998 with overwhelming bipartisan support (29-3 in the Senate and 91-6 in the Assembly). The law required mining companies to prove that a sulfide mine had operated for 10 years (and closed for 10 years) without polluting groundwater and surface waters with acid drainage. Wisconsin was the only state with this requirement which shows how Wisconsin USED to be a leader.

In 20 years, no mining company was able to provide this proof. This CONSERVATIVE (in the true meaning of the word) law errs on the side of protecting Wisconsin’s water. In the absence of proof that mining can be done safely, protecting water must come first. Water IS the most important natural resource.

This common sense requirement, however, does not fit the radical Republican ideology. For them the “free market” and profit overrides all other considerations. In 2017 The Walker administration repealed the “prove it” law. In addition they weakened wetland and groundwater protections, reduced the time DNR regulators had to review mine plans, limited legal challenges to state mining permits, exempt mine companies from fees that cover costs of handling hazardous waste, and reduced the  financial liability for mining companies for later clean up costs.

Mining advocates claim the Flambeau mine in Wisconsin proves sulfide mining can be done safely. The mine was an open-pit copper, gold, and silver mine located near Ladysmith. The international company Rio Tinto (former Kennecott Copper) operated a 35-acre open pit mine between 1993 and 1997. The mine produced 181,000 tons of copper, 3.3 million ounces of silver and 334,000 ounces of gold, according  Department of Natural Resources records. Today the 181 acre property has been filled in, replanted, and wetlands created. It is open to the public for recreation. This is the last mine of its kind to operate in Wisconsin prior to the “proof it” law passed in 1998.

But although the surface reclamation looks good, environmental groups say surface and ground waters are still being polluted. Groundwater samples indicate high levels of copper, manganese and sulfates. An intermittent stream flowing through the property contains high levels of copper and zinc. In 2014 water samples from the stream did not meet DNR water quality standards. Water treatment to mitigate pollution in the stream currently continues and  sampling in 2017 showed that the copper levels continue to exceed the acute toxicity criteria. Twenty years after it closed a final Certificate of Reclamation from the DNR has not been issued.

But hope springs eternal. The gold rush mentality and the hope for an economic savior are strong. Unfortunately “ONLY WHEN THE LAST TREE HAS BEEN CUT AND THE LAST RIVER BEEN POISONED AND THE LAST FISH BEEN CAUGHT WILL WE REALIZE WE CANNOT EAT MONEY.”