Mining exploration near headwaters streams causes pollution concerns

Companies seek mineral deposits that could lead to a risky mine near the Kettle River.




6 minute read

The Kettle River. (Photo by Michael Hicks via Flickr)

“The Kettle River Watershed is a Minnesota treasure. This watershed is an outdoor enthusiast’s playground, with two Minnesota state parks and several recreational areas in and around this watershed… Maintaining the beauty and water quality of the Kettle River Watershed should remain a top priority.”

– Minnesota Pollution Control Agency

For the last several years, a coalition of mining companies has been studying bedrock buried below bogs and streams southeast of Duluth that may contain valuable minerals. The area includes the headwaters of the Kettle River, a wild and beloved tributary of the St. Croix, and the Tamarack River, which flows toward the Mississippi.

While the exploration has been little publicized so far, a mine in such a location raises concerns about water pollution and other environmental damage. When the type of rock being targeted is dug up and exposed to air and water, it can create acid that absorbs other harmful substances from the rock and runs into nearby lakes and rivers.

The Environmental Protection Agency calls hardrock mining the top polluting industry in the United States, and there is a long history of problems at such operations around the world.

This summer, crews are again drilling another dozen deep holes near Tamarack, Minn. They’re analyzing the rock, trying to determine if it’s worth digging up on behalf of a small company called Talon Metals Corp., which is partnered with multinational conglomerate Rio Tinto.

“Their goal seems to mostly be to expand their knowledge of the size of their discovery,” says Don Arnosti, an environmental advocate who has been following the project. “They have geological indications that there may be a larger ore body down than they have proven.”

The companies have locked up mineral rights owned by the state of Minnesota, drilled numerous holes to extract rock samples, and surveyed the area using electromagnetic techniques involving airplanes, drones, and grids of wires on the ground. They have found tantalizing evidence of nickel, copper, palladium, and other metals.

Talon says it would seek to sell such minerals to manufacturers of stainless steel or electric vehicle batteries.

A project with potential

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In May, Talon announced its last round of exploration activities was very successful.

“As expected, the winter 2020 exploration program assay results are fantastic, especially considering that these grades are significantly higher than estimated average global underground nickel mining grades,” said Henri van Rooyen, CEO of Talon.

Last month, the DNR approved another exploration proposal from the company. Most of the state-owned leases are also under state-owned surface lands.

The mineral exploration zone spans the divide between waters that flow toward Big Sandy Lake in the upper Mississippi region, and the West Branch of the Kettle River, where water eventually ends up in the St. Croix.

Split into two parts roughly by Highway 210, the companies are approaching exploration as two separate but related projects. The most intensive exploration so far has been in the northern part of the zone, outside the St. Croix’s watershed, but a valuable region for wildlife and outdoor recreation in its own right.

The southern portion, closer to the Kettle River, showed little potential until 2016, when a drill hole “returned encouraging assay results for the first time.”

“In the current exploration state, the Tamarack South Project remains an early stage project with great potential for a Ni-Cu-PGE massive sulphide deposit,” Talon told investors in December 2018.

The company will probably slowly expand the area it’s exploring, first seeking to prove a small deposit and using that to attract the financial investments necessary to do more.

Public resources, private benefits

Arnosti, who has been working on mining issues in Minnesota for decades, and currently serves on the board of Minnesota nonprofit WaterLegacy, says important decisions are being made without significant input from its citizens.

“There are a lot of public resources at risk, but decision-making is happening without the public being involved,” Arnosti says.

(Note: Arnosti will give an online presentation next week about the project to help raise awareness and inspire public involvement, with a limited number of viewers. St. Croix 360 has interviewed Arnosti, researched the issue, and published this article to help extend awareness of the issue even further.)

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Arnosti first got involved in mining issues as the project manager for a state study in the 1980s that included the Department of Natural Resources, environmentalists, and the mining industry. He says it was a different time, when opposing interests still talked to each other and tried to work together.

But after the study was completed, Arnosti says the DNR and the industry cut out environmentalists and wrote rules to regulate precious metal mining. He says time has shown those rules are inadequate to protect water, taxpayers, and future generations.

In 2018, the DNR issued its first permit for a sulfide ore mine for the controversial PolyMet project in northeastern Minnesota. Most of the major decisions have been blocked by courts for being inadequate or unenforceable.

“The thing that concerns me the most is that, in my opinion, our state has zero credibility and zero track record of being an effective regulator of mining,” Arnosti says. “It doesn’t matter what this company proposes, and promises, they will not be held to it.”

He has watched over the past years how the DNR has been challenged in regulating the mining industry because of what he sees as an outdated dual mission: to both promote mining and protect the environment.

“I really believe we have a policy that was put in place generations ago, that says the mineral wealth of Minnesota should be developed,” he says. “But perhaps the social compact changed, and the laws should change.”

Power of the people

A typical bog in the region. (Photo by Marcel Holyoak via Flickr)

Arnosti is trying to start a statewide discussion about where Minnesotans want mining to occur, even before the state government starts issuing exploration leases. For example, there are buffer zones around the Boundary Waters Canoe Area Wilderness, and some advocates are attempting to make the entire area upstream of the wilderness off-limits to mining.

“It’s not like I’m inventing a concept that’s not in use,” Arnosti says. “We, the public, should realize everywhere minerals exist are not necessarily the right place to extract them for the benefit of society at this time. It’s absolutely a unilateral decision that the public can make about its own mineral rights.”

Watery landscapes like the headwaters of the Kettle and Tamarack Rivers may also be inappropriate to even consider mining at this time. While there are few large lakes in the area, more than half the area that drains into the West Branch Kettle River is wetlands.

It seems like a risky location for mining that causes problem when it gets near water.

Arnosti suggests that Minnesota should consider something like zoning for mining, with a conversation about the industry’s role in the state, and where it is and is not appropriate. Ideally, this would be done before any more publicly-owned mineral leases are handed over to private companies, which may put considerable time and money into a project before the question ever comes up if Minnesotans want a mine there.

The Tamarack leases are already locked up for decades to come. That doesn’t necessarily mean there will be a mine.

Many maybes

There are many possibly promising deposits around the world, and large mining corporations have to be choosy about which ones they pursue.

Rio Tinto, which owns roughly $80 billion in mineral resources around the world, had previously pushed exploration of the Tamarack deposit, but eventually handed the initiative over to Talon.

“They see it as a sure enough bet they didn’t want to let it go, but no longer wanted to invest in it,” Arnosti says.

Arnosti says some veins of ore have been discovered that could make the mine more profitable than the PolyMet project. So far, the Tamarack deposit appears to be small — and rich.

Enlisting a junior partner like Talon is a common practice in the industry. The smaller company is comprised of mining industry insiders with extensive experience developing projects, including representatives from Rio Tinto. On paper, the corporation is based in the British Virgin Islands, a known tax-shelter. The company’s task is to find investors and move the mine forward.

Rio Tinto still owns the leases and mining rights, while Talon is attempting to earn a majority share by investing in exploration, making cash payments to Rio Tinto, and meeting certain milestones.

Talon can secure a 60 percent share if they complete exploration and a mine feasibility study by 2026. Then would need to come a proposal, environmental review, and permitting to actually extract ore from the Tamarack project.

That leaves time for Minnesota to make up its mind about mining, even while it wrangles with other similar projects in the works.

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2 responses to “Mining exploration near headwaters streams causes pollution concerns”

  1. Carol Lehman Avatar
    Carol Lehman

    THE DNR ONLY MAKE AMAZING DECISIONS FOR US. The St.Croix river is one of the few clean rivers in the United States and the DNR has tried their best to pollute it for years. MONEY is the key to the DNR, if you have a large budget they are ready to talk. My parents bought a cabin on the St.Croix when I was a child, I am now 73 the woods were full of animals of all kind…Not anymore, they have made sure that they, ( including deer),have been killed off, They introduced wolves and troubled bear from other areas..You can’t even safely go for a walk. Now they want the river!

  2. Julie Avatar

    This is a pattern in Minnesota — the Polymet mine will also result in sulfur acid runoff into the Lake Superior watershed and the Twin Metals proposed mine on the eastern edge of the Boundary Waters Canoe Area Wilderness is a similar polluting operation. Companies claim that the sought minerals and ores will help electric cars and cell phones, anticipated to be in more demand in future. It’s a huge price to exchange them for precious, clean, drinkable, fishable, swimmable water. Minnesota’s mining regulations were never written for mines near water … we need more substantive protections. Get involved.


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Mining exploration near headwaters streams causes pollution concerns