Inco Superstack
Coordinates: 46°28′48.23″N 81°3′23.43″W / 46.4800639°N 81.0565083°W
The Inco Superstack in Sudbury, Ontario, with a height of 380 metres (1,250 ft), is the tallest chimney in Canada and the Western hemisphere, and the second tallest freestanding chimney in the world after the GRES-2 Power Station in Kazakhstan. It is also the second tallest freestanding structure of any type in Canada, behind the CN Tower but ahead of First Canadian Place. It is the 40th tallest freestanding structure in the world. The Superstack is located on top of the largest nickel smelting operation in the world at Inco's Copper Cliff processing facility in the city of Greater Sudbury.
The Superstack was built by Inco Limited (and later purchased by Vale) at an estimated cost of 25 million dollars. Construction on the structure was underway during the Sudbury tornado of 20 August 1970; the structure swayed heavily in the wind, but remained standing and suffered only minor damage. Six workers were on top of the construction platform when the storm hit; all six survived, but quit their jobs the following day. The same day was the final day of construction on the stack, with the construction fully completed by the evening of August 21.
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