Notice of Incident

UPDATE December 25, 2020 6:05 p.m.

The incident was a series of eruptions that occurred during the Slag Casting process – when slag and molten iron from the Blast Furnace are separated and the slag is cast. In this case liquid slag / iron came into contact with moisture which caused the eruptions. (The Blast Furnace produces liquid iron used in steelmaking. Slag, a byproduct, is cast, then pelletized and used in aggregate applications).

The reaction was between water and primarily liquid iron and would have been comprised of mostly iron, iron oxide and water vapour, as well as silica, calcium, magnesium, carbon dioxide, and carbon monoxide. 

ORIGINAL POST December 25, 2020 12:20 p.m.
At approximately 11:10 a.m. a slag pit eruption occurred at the No. 4 Blast Furnace. Thankfully there are no injuries. However the event caused a significant air emission. Ministry of Environment, Conservation and Parks have been alerted.

Both ArcelorMittal and Hamilton Fire attended. Hamilton Fire has now left. The site is secure.

We will provide an update when available.

About ArcelorMittal Dofasco

About ArcelorMittal Dofasco ArcelorMittal Dofasco is Canada’s largest producer of flat carbon steel and is part of the world’s largest steel and mining company. Headquartered in Hamilton, ON, with more than 4,500 employees each year we ship 4.5 million net tons of high-quality flat carbon steel to partners in automotive, energy, packaging and construction which are used in increasingly lighter, stronger and more sustainable products – from cans to cars. Our purpose is to produce ever smarter steels that have a positive benefit for people and planet. High performance steels made using innovative processes which use less energy, emit significantly less carbon and reduce costs. Steels that are cleaner, stronger and reusable. With steel at our core, our inventive people and an entrepreneurial culture at heart, we will support the world in making that change. This is what we believe it takes to be the steel company of the future. For more information about ArcelorMittal Dofasco, please visit:

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