For years, residents and visitors to Sudbury, Ont., knew they were approaching the Nickel City when they saw the Inco Superstack.

“For us, it’s a beacon in our community,” Sudbury Mayor Paul Lefebvre told Global News. “You see Superstacks, you’re near home, right? You’re almost there because you can see it from pretty far away.”

But the skyline of Sudbury is undergoing a drastic change as plans are underway by current owner Vale Base Metals (VBM) to tear down the structure, as well as its neighbouring copper sister.

The company has made the Superstack and its little copper sister obsolete by finding more environmentally friendly way of dealing with emissions.

Before the arrival of the chimney, which residents refer to as “the Smokestack,” Sudbury was known as an environmental disaster, as spewing toxins made vegetation and wildlife in the area disappear.

“Vegetation could not survive,” Lefebvre said. “And certainly in the Copper Cliff area (where the mine is located) was really bad.”

Then came the Superstack in 1972.

Standing more than 1,250 Ft. high, it was, for a short time, the largest freestanding structure in the Western Hemisphere until it was surpassed by the CN Tower. Until it disappears, it will remain the largest chimney in Canada.

“If you look at the history of why it was built, it was just to get the sulphur to go further instead of having it landing right beside the community,” Lefebvre said.

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He noted that while that was a major innovation for its time, things have continued to evolve. In 2010, VBM, which acquired Inco in 2006, first announced the Clean AER Project, which would see the towering chimneys replaced with environmentally friendly and efficient methods of dealing with nickel extraction.

“The Superstack and Copperstack have been iconic landmarks in Greater Sudbury for decades,” said Gord Gilpin, director of Ontario operations for VBM.

“While we appreciate that the city’s landscape will look different after these structures are dismantled, our business has evolved and improved over time and this project is part of that evolution. We are modernizing our facilities and reducing our environmental footprint and, in so doing, laying the groundwork to ensure that our next century of mining in Sudbury is as successful as our first 100 years.”

The company says the move will eliminate 100,000 metric tonnes of sulphur dioxide emissions each year (equivalent to 1,000 railway tanker cars of sulphuric acid). It will also see the end of the Superstack and its copper counterpart, as they were decommissioned in 2020, and have been dormant ever since.

The company is just about finished with the demolition of the smaller Copperstack and is expected to turn its attention to the Superstack this summer.

“It’s a massive undertaking of how they’re going to do this,” Lefebvre said. “They had to prep for it the last five years and here we are, we’re on the cusp of it.”

The company says it will take about five years to pull down the towers and while some have argued that the towers should remain as a tribute to the city’s mining history and effort to clean up, the mayor said that is not a realistic option.

“There are some folks in the community that think we should keep it, but again, it’s not ours, right?” he said. “It’s the company’s and it’s a liability, because if they just leave it there, the whole thing will rust and the inside will, then it becomes a liability.”

Lefebvre also noted that the structure sits atop an active nickel mine, so there is no way it could ever be an attraction for people to visit and would be something that would need to be admired from afar.

While he is sad to see it go, the mayor noted that it is a weird twist that a place that once held such a bleak landscape would hold such an important stake in the world’s environment.

“The irony of all this is now Sudbury, that was one of the most polluted places back in the ’30s, ’40s, ’50s and ’60s, is now obviously contributing enormously with our critical minerals to our environment,” he said. “All electric vehicles and all battery, it needs nickel and we are the ones providing that across our entirety in the world.”

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