Demolition continues at Sudbury's iconic Superstack that sits on Vale property in Copper Cliff, west of Sudbury.
The structure that was considered an engineering marvel more than 50 years ago is now the focus of an engineering challenge as workers are in the process of dismantling the structure, which stands at 1,250 feet. Work began in the past week.
Vale said it has made “significant progress” toward commissioning the special proprietary equipment for the dismantling procedure.
“At the end of August, this equipment was successfully raised to the top of the structure — an important project milestone. To facilitate the hoisting of this equipment, three access pockets were created along the stack,” said an email from the company.
The company added that safety is a top priority.
“Exclusion zones have been established, protective barriers have been installed to safeguard nearby assets, and robust monitoring protocols are in place to ensure safe operations throughout the demolition,” said Vale.
In the coming weeks, observers will notice the gradual lowering of the upper work platform as demolition continues, the company added.
The steel liner that previously formed the inside of the stack when it was in operation has been removed. This now allows workers to break away the concrete, piece by piece, starting from the top of the structure.
Workers can access the top of the stack by riding on one of the two access elevator/climbers attached to the outside of the structure. The elevators are branded with the name Alimak, which is the name of the company that has supplied elevating devices for Canadian mines for decades.
Slabs of concrete roughly nine and-a-half inches thick at the top of the stack are being broken off and allowed to free fall to the bottom of the stack. The thickness of the concrete gradually widens toward the bottom of the structure, where the supporting concrete walls are 40 inches thick, said a video about the demolition process that Vale produced in May.
Once a sufficient pile of broken concrete has accumulated at the bottom of the stack, after a number of days, a remote-controlled loader will be used to muck out (clear) the debris from a special access door at the bottom.
Over a period of time, the stack will eventually be reduced to about 20 metres in height. At that point the elevators and machinery will be removed and the demolition will be done using large conventional excavators, said the video.
In terms of a timeline, the video said the work could take up to five years. Demolition work will be paused during the winter months when temperatures are below freezing.
In recent weeks, the dismantling procedure has been an item of interest on social media in Sudbury with several people commenting that it would be appropriate to somehow keep the stack as an historic landmark that people can visit.
The company that is not a viable solution. An explanation was provided on the company website.
"The Superstack is wholly contained within Vale’s Copper Cliff Smelter Complex property and there is no safe viable public access. As an active and busy industrial site, access is strictly controlled and monitored for safety as there are hazardous materials and moving equipment moving throughout the complex. Our policy requires visitors to wear personal protective equipment and be escorted when moving within the smelter," said the company.
In addition, Vale said there is a significant cost to maintaining the stack.
"Vale understands and appreciates the Superstack’s significance to Sudbury's identity and history. However, maintaining such a large structure isn't just about preserving a landmark — it's about ensuring the safety, viability, and sustainability of that decision," the company said.
"The costs involved aren't merely financial; they include ongoing safety considerations, environmental impacts, and the infeasibility of adapting an aging industrial structure for modern use.
"For these reasons, a decision to apply resources to dismantle the Superstack is the responsible way to serve current and future generations," said the company.
A YouTube channel with the name Suds4Ever Adventures released a drone video of the demolition last week. The video has hundreds of views and counting.
Len Gillis covers health care and mining for Sudbury.com.
