Mining 101

Exploration

Our exploration team is in charge of finding mineral deposits of beneficial scale. Ultimately, the end goal is to locate a mineral source that is both environmentally and economically viable to extract. Eagle Mine is the only Greenfield mine (area not previously mined) in the United States and the first in decades. To maximize opportunities in the region, we continue to explore for additional resources in the Upper Peninsula of Michigan.

Geology

The Eagle deposit was formed during the Midcontinent Rift tectonic event 1.1 billion years ago. This rifting, or breaking apart, separating, and thinning of the Earth’s crust allowed magma deep within the Earth to rise up through the crust and cool as igneous bodies. The Eagle deposit was the result of at least three different intrusions of magma rich in metals. As the magma cooled, nickel and copper minerals crystallized into a solid ore body. The bottom of the ore body sits roughly 1,000 feet deep and measures to be roughly 6 acres in size. Eagle has two ore types; massive and semi-massive sulfide. Massive sulfide is about 6.5 per cent nickel and 3.8 per cent copper. Semi-massive contains about 1 per cent nickel and 1 per cent copper. The Eagle deposit is high-grade nickel and copper, but also contains trace amounts of cobalt, platinum, palladium, silver and gold.

Drill

Blast

Muck

Backfill

Mining

At Eagle Mine, underground mining employs long-hole stoping techniques to recover the ore. The deposit is accessed via a 1 mile long decline tunnel measuring about 18 feet in diameter. Ore is transported to the above ground Coarse Ore Storage Area (COSA) by low-profile, 45 ton loaders. Inside the COSA, a front end loader will fill road haul trucks with ore on average 18-24 inches in size. Truck loads are covered before passing through the truck wash and continuing off site to travel approximately 66 miles to the Humboldt Mill. Eagle will be mined from the bottom –up, and backfilled with a mix of rock, aggregate, and cement as the levels are mined.

Milling

Conventional crushing, grinding, floatation, and pressing are used to process run-of-mine ore into separate nickel and copper concentrates. Road haul trucks arrive to the mill and dump their load in the enclosed Coarse Ore Storage Area. Each truck load weighs on average between 40-45 tonnes. Ore will go through three stages of crushing before the grinding circuit pulverizes the ore to 80 microns (a texture similar to fine sand). Water is introduced and a series of floatation separates the nickel from the copper. We work to remove as much water as we can by thickening and pressing the mixture. Rail cars are then filled by a front end loader, covered and sent to our customers. Nickel and copper concentrates will then have to go through smelting and refining before becoming 99.9 per cent nickel and copper. The material left over once the nickel and copper have been extracted is referred to as tailings. The tailings are sent to the Humboldt Tailings Disposal Facility (HTDF) where they are stored under water. Water from the HTDF is decanted off the top and pumped back to the mill as process water. Excess water is treated at the on-site water treatment plant before being recycled to the environment.

Crush

Grind

Float

Press

Transportation

Our transport plan uses existing roads for ore transportation; including Triple A, CR510, CR550, Sugarloaf Avenue, Wright Street, US41, M-95 and CR601. Eagle Mine has an agreement with the Marquette County Road Commission for $44 million to upgrade these roads. Haul trucks adhere to all Michigan Department of Transportation guidelines, including those for length and weight. Approximately 44 round trips are made per day between the mine and mill sites with each load weighing on average between 40-45 metric tons. Safety is stressed with our ore truck drivers, which is why we constantly monitor speed, location, and braking efforts throughout the entire transportation process.

Health & Safety

Safety is not about numbers – it’s about people. Our goal is an injury free workplace where everyone goes home safe each and every day. Our approach begins with an effort to eliminate hazards from our operations. We spend a significant amount of time training our employees and contractors to stay safe and healthy on the job site. While on-site, we ensure everyone wears proper Personal Protective Equipment (PPE) to guard them from any hazards that they may come in contact with. We’ve built a culture where employees and contractors consider their own safety as well as the safety of those around them. We work every day to maintain our goal of zero harm.

The Products We Produce

Nickel

From medical equipment to transportation, nickel is found in many of the products that make modern life possible. Manufacturers often prefer to use nickel alloys over other materials because they are more resistant to corrosion, tolerant of high and low temperatures, strong and contain magnetic and electronic properties. At the end of their useful life, about 25 to 35 years, nickel products are easily recycled for future use. In fact, about half of the nickel in modern stainless steel products comes from recycled sources. Eagle will produce 360 million pounds of nickel.

Copper

Today copper can be found in many of the products that we use every day including home appliances, vehicle parts and electrical components. Copper can easily be shaped, molded, rolled into sheets, or drawn into thin wire. It does not easily rust and is an excellent conductor of electricity and heat. In many respects, modern life would not be possible without copper. Eagle will produce 295 million pounds of copper.