With precious metals in need, Focus shifts to polymet Dam

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HOYT LAKES — Driving along the towering landscape, dotted with swans and animal tracks — moose or deer is the consensus of the truck — and sagging fall colors on this mid-October day, it’s hard to imagine a place can be fraught with both controversy and local hopes of economic vitality

But it is, because here is PolyMet and the 250-foot-tall tailings basin at the former LTV Steel Mining, where the PolyMet Mining Corp wants wants to build Minnesota’s first copper-nickel mine using the remnants of the old for the new. That includes building a tailings dam similar in height for the NorthMet project.

For most of the past 14 years — the amount of time the company has gone through environmental review — there was a quiet anticipation among Iron Rangers as PolyMet slogged through the tedious finer points of its proposal. That suspense turned in 2019 when state and federal regulators approved the final permits. It wasn’t if the project but would be built, but when.

Along the way, the company was winning its court battles against environmental groups opposing the project until another turning point. The tailings dam at Brumadinho mine in Brazil, owned by mining giant Vale, collapsed and killed 270 people. It raised alarm bells across the industry about the inspection woes that often go hand in hand with mines in South America, but also the upstream dam design of Brumadinho.

Those alarm bells sounded in Minnesota, where environmental groups have started winning their own court battles centered around PolyMet’s dam — planned with an upstream design. The Minnesota Court of Appeals recently extended a stay on the project’s permit to mine and dam permit following a court hearing where opponents of the project raised their concerns about the dam and PolyMet’s new majority owner, Glencore, a Swiss mining behemoth with a spotted environmental track record of its own.

The appeals court could throw a severe wrench into what the company and its supporters hail as a jobs creator — hundreds in direct and indirect, not to mention millions of hours in construction — once a shovel gets into the ground. Judges have 90 days from the Oct. 23 hearing to decide on the future of the permits. If they order a contested case hearing in front of an administrative law judge, that could extend the permits’ hold for at least another year.

On this day, however, less than a week before the hearing, the team at PolyMet doesn’t seem worried. Or at least they’re not showing it.

An upstream climb from here

The upstream dam design packs tailings into a large stair-like model. There’s estimated to be about 500 cross the United States and on the Iron Range, PolyMet’s planned design is far from the only upstream basin. Four of the existing taconite mines — Keetac in Keewatin, Minntac in Mountain Iron, Minorca in Virginia and Hibbing Taconite in Hibbing — utilize an upstream dam. United Taconite in nearby Eveleth utilizes a centerline/upstream, while Northshore in Babbitt uses solely a centerline design.

“They’re all unique,” said Brad Moore, executive vice president of environmental and governmental affairs for PolyMet. “You have to look at them individually, that’s the key.”

According to Christie Kearney, environmental site director for the company, landscape is the biggest difference from the Iron Range and the disaster at Brumadinho, which was built on a mountainous terrain in Brazil. Northeastern Minnesota is relatively flat and not known for weather extremes beyond the frigid cold winters.


The design of PolyMet’s dam can hold, according to their models, a Biblical rainfall of 35 inches in a matter of 72 hours, more than five times the amount of rain that fell in the devastating Duluth flood in 2012.

“That’s Moses’ flood,” Kearney said of the tailings basin’s projected capacity, noting it was the most inexpensive route.

Kearney said the company looked at dry-stack tailings, the method that neighboring copper-nickel mine Twin Metals plans to propose, but federal regulators considered the upstream design the “least environmentally damaging of the practicable alternatives,” known by the federal acronym of LEDPA.

But those projections aren’t going to quiet the detractors anytime soon. Upstream dam designs were getting closer looks by governments, including in Canada, before what happened at the Brumadinho collapse was a forethought.

The U.S. Army Corps of Engineers monitors more than 1,300 tailings dams and, according to a recent report by the Wall Street Journal, about a quarter of them have a “high” risk of severe hazard potential, meaning a failure could result in loss of human life. Upstream dams are effectively banned in Canada and also in parts of the European Union, primarily places with high risk of seismic activity.

These are points the environmental groups opposing PolyMet have capitalized on in the arguments that have drawn second looks by the Minnesota courts.

“Why is an upstream construction method good enough for Minnesota, when Brazil has found this design so unacceptable that old upstream dams must be decommissioned as well as new ones prohibited,” said Paula Maccabee to the Journal. She’s an attorney with Water Legacy, one of the environmental groups fighting the PolyMet project.

Aside from the landscape and capacity for rainfall, company officials point to the state’s calm seismic activity, the environmental review standards of Minnesota and the technology of their upstream design — which features a rock buttress, a more conservative grading angle and more than 200 monitors across the site to help detect any issues, like stability, before they become disasters.

Jess Richards, assistant commissioner of the Minnesota Department of Natural Resources, said the state refers to most of the upstream dams as “modified upstream construction” because of rock buttresses or perimeter containment dikes.

“No two tailings basins have the exact same design and many have used more than one design over time or in different areas,” he said.

The DNR requires mining companies with active tailings dams to submit annual reports that include updates on completed construction, monitoring results, material testing, operations, major maintenance work, photos and any problems they have come across.

Safety engineers inspect active tailings dams every four years, and depending on the dam, more frequently up to annually. Inactive dams are required to be inspected every eight years and in some cases up to every four years.

The state also performs site inspections by reclamation specialists at least once a year on permitted mines to check on the tailings dams. Those visits focus on vegetation cover, slope health of the bains and erosion.

“All of our inspections document any needed repairs and ensure that proper corrective action is taken by the company,” Richards said.

At the former LTV tailings dam, he said inspection occurs every four years, and once construction starts on the NorthMet dam, the DNR will inspect it “at least annually.” PolyMet is required by the state to have an annual dam inspection by a qualified engineer licensed in Minnesota, with that report provided to the DNR.

PolyMet Mine

In this photo taken Feb. 10, 2016, binders of the final environmental statement for the proposed PolyMet mine sit on a table at the company headquarters in Hoyt Lakes, Minn. The Department of Natural Resources announced Thursday, March 3, 2016, that it has approved the final environmental review for Minnesota's first copper-nickel mine. (AP Photo/Jim Mone)

Push for more precious metals

The full-court press by environmental opponents of PolyMet comes at a sort-of flex point for the market. With the U.S. in a full-on trade war with China, the country is looking for sources of domestic precious metals to fuel the green economy of solar and wind power and electric vehicles, as well as for use in the nation’s defense.

Technology companies are also looking for new sources of these metals, if not domestically, than in more regulated areas of the world that don’t employ child labor or send mining profits to illicit organized crime.

Take Colombia for example, which remains part of the gold supply chain for Apple. According to a recent report by The New York Times, Colombia gold is now more lucrative for organized crime cartels than cocaine, and the U.S. is one of the biggest buyers of Colombian gold.

As more states are requiring car manufacturers to supply more electric vehicles to the market, the federal government has been simultaneously pushing to streamline mining permits for rare earth metals critical to manufacturing the vehicles.

It’s been a recent focus of President Donald J. Trump amid his administration’s trade war with China, which has threatened rare earth shipments from the country.

Aside from EVs, lithium and copper are key components of defense technology used by the federal government.

Trump issued an executive order this year directing the Pentagon to find rare earth sources outside of China, according to Reuters, and legislation is being introduced in Congress to streamline mining permits and fund geological studies.

Such efforts represent an opening in the domestic market for companies like PolyMet.

According to the company, its mine plan accounts for 1.16 billion pounds of copper, 170 million pounds of nickel, 6.2 million pounds of cobalt and 1.56 million ounces of precious metals, including 1.19 million ounces of palladium and .37 million ounces of platinum/gold.

The Duluth Complex, the formation on which PolyMet, Teck, Encampment Minerals and Twin Metals sit, contains one of the world’s largest known undeveloped supplies of copper, nickel and platinum group metals (PGMs).

In the U.S., it accounts for the second-largest supply of copper, third-largest supply of nickel and second-largest supply of PGMs.

“The resources is our biggest asset,” said LaTisha Gietzen, a public and community relations spokesperson for PolyMet. “There’s more ore than what we’re permitting.”

Minnesota is now one of the states planning a push for more electric vehicles in dealership lots, a new rule Gov. Tim Walz has directed the state Pollution Control Agency to enact next year, effective for the 2023 model year.

It would also open the door for Minnesota to unlock a new manufacturing sector as a maker of EVs, an initiative Walz has referenced when discussing how PolyMet’s proposed copper-nickel mining project fits into his plan for a clean energy future.

“I want to unleash the innovation we have here — it makes sense for us to be a manufacturing state,” Walz said in a September conference call, when asked how PolyMet could complement EV growth. “This seems to be that fit.”

Copper is an essential part of EV production used in motors, batteries wiring and charging stations for the cars.

One EV, according to the Copper Development Association, uses between 85 and 183 pounds of copper.

PolyMet is also promoting this potential market, using the CDA figures in recent presentations to investors and communities.


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