Osisko Mining Corp., which operates the Malartic gold mine in Quebec, said an investigation by provincial authorities at the project is connected to faulty explosives supplied by a contractor.
Some of the explosives supplied by Orica Mining Services Ltd. released levels of nitrous oxide that exceeded environmental rules, Osisko Chief Executive Officer Sean Roosen said yesterday in an interview.
“Some of it has been human error, most of it has to do with the blasting products and that has been subsequently rectified,” he said by phone.
Osisko said Nov. 28 that investigators from Quebec’s environment ministry searched the mine that day and seized documents related to drilling, loading and blasting activities for dates between April 2011 and October 2012.
“Orica will assist the Canadian authorities with their enquiries,” Ben Wilson, a spokesman for Orica Mining Services, a unit of Melbourne-based Orica Ltd., said today by phone.
Osisko said operations at the mine, which began commercial production in May 2011, are continuing as normal. Fewer than six blasts had problems out of more than 700 carried out this year, Roosen said. The nearby town of Malartic wasn’t in danger because the company won’t blast when the wind is blowing in that direction, he said. Osisko reported the problems to regulators and has cooperated with the investigation, he said.