Work to dismantle Sudbury’s Superstack ahead of schedule

Jonathan Migneault · CBC News

· Posted: Oct 31, 2025 6:05 AM EDT | Last Updated: October 31

The Superstack successful the bluish Ontario metropolis of Sudbury was the world’s 2nd tallest smokestack astatine the commencement of the summer, but present it’s dropped to the eighth spot.

Mining institution Vale started a five-year occupation to dismantle the schimney this year, and is up of docket according to task pb Paul Guenette.

“We achieved our extremity and past immoderate by astir double,” Guenette said his team's advancement implicit the summertime and fall.

Using a instrumentality called "the mantis," Guenette said crews are chipping distant astatine the factual operation from the wrong out. To date, they've reduced the Superstack’s tallness by astir 35 metres.

It present stands astatine astir 345 metres.

The Superstack was built successful the aboriginal 1970s to disperse sulphur dioxide emissions from the company’s smelter implicit a wide area.

But with improvements successful technology, arsenic good arsenic stronger anti-pollution legislation, Vale completed its $1-billion Clean AER task successful 2020, meaning the stack was nary longer needed.

Guenette said Vale is present capable to seizure astir of those emissions astatine the source, and enactment up 2 overmuch smaller stacks astatine its Copper Cliff smelter complex.

“They needed to instrumentality it down successful bid to mitigate the hazard of immoderate further deterioration to it,” Guenette said.

He said pieces astir the size of a ping-pong array were being dropped down the stack and astir erstwhile a week that rubble was hauled distant and dumped successful 1 of Vale's aged unfastened pit mines.

The enactment has present stopped for the winter.

The Superstack is expected to beryllium wholly gone from the Sudbury skyline by 2030.