What we know about NorthMet, Minnesota's first copper-nickel mine

The first ever copper-nickel mine in Minnesota could be one step closer to coming to life following the submission of a mine permit.

PolyMet Mining, the Toronto based mine development company, has submitted a Permit to Mine Application to Minnesota Department of Natural Resources Mine Waste Management.

The Permit to Mine is one of several major permits required to construct and operate the NorthMet copper-nickel precious metals project located in northeastern Minnesota.

The application is the last of the major permit applications, following submission of water-related and air quality permit applications to the Minnesota Pollution Control Agency (PCA) and DNR during the summer.

What is the NorthMet copper-nickel precious metals project?

The NorthMet Project is part of northeastern Minnesota’s Duluth Complex, one of the world’s largest known undeveloped deposits of copper, nickel and other precious metals.

As mentioned above, it would represent the first in Minnesota to commercially extract metals from the Duluth Complex.

PolyMet has estimated that the project will produce 72 million pounds of copper, 15.4 million pounds of nickel, 720,000 pounds of cobalt and 106,000 troy ounces of precious metals on an annual basis.

Specifically, the NorthMet deposit is located in the Partridge River Intrusion of the Duluth Complex. It is a large tonnage disseminated sulphide deposit in heterogeneous troctolitic rocks associated with the 1.1billion-year-old Mid-Continent Rift.

Say that three times without failing.

The 1.1billion year-old Mid Continent Rife contains copper, nickel, cobalt. Platinum, palladium, gold and silver – a very rich deposit indeed.

The NorthMet Project contains two assets of note, obviously, the deposit itself and the former Erie processing facilities and infrastructure that together cover approximately 16,700 contiguous acres – which we can say is around 26 square miles.

Should the company receive mining permits, the mine will operate for 20 years at a mining rate of 32,000 tons of ore per day.

The mine itself will consist of three open pits, the West Pit, the East Pit and – yes of course, the Central Pit. 

Ore from the mine will transported six miles west to a processing facility via rail. The facility, which was idled in 2001 and purchased by PolyMet in 2005, is designed to process 32,000 tons of ore per day.

The company, through independent research, believes that through the NorthMet Project:

• More than 600 indirect and induced jobs in goods and services and other sectors where PolyMet dollars will flow.
• $515 million annually in St. Louis County alone in wages, benefits and other spending. This amounts to more than $10 billion over the 20-year life of the mine.
• $15 million annually in state and local tax revenues, or $300 million over the life of mine.
• $45 million annually in federal tax revenue, or $900 million over the life of the mine.
• More than $2 million annually for northeastern Minnesota schools.

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Get in touch with our editor Dale Benton at [email protected]