Glencore accused of discharging copper concentrate dust at Horne smelter in Quebec

Fonderie Horne, a foundry owned by Glencore, is seen in Rouyn-Noranda, Que., on Oct. 29, 2022. (Stephane Blais/The Canadian Press)

Glencore’s Horne smelter in western Quebec is facing a charge under the province’s environmental laws for allegedly releasing copper concentrate dust into the air in March 2023.

Quebec’s Environment Department said in a statement on Friday the charge stems from an investigation it carried out after officials were called to the copper smelter on March 7, 2023, in Rouyn-Noranda, Que.

At the time, several residents shared photos on social media of what they described as “black snow.”

In an email Friday, Glencore Canada said that in the aftermath of the 2023 incident it released a statement explaining that wind gusts and low snowfall, which led to an exceptional dry stockpile of copper, were to blame.

The company said in the email that in 2023 it inspected the site, contacted the environmental officials, and conducted a cleanup operation at a cost of several hundred thousand dollars.

“Since then, we have reviewed our stockpile management to prevent a recurrence of such an event,” the company said.

Glencore Canada could face a minimum fine of $30,000.

This report by The Canadian Press was first published Aug. 1, 2025.