Three BC engineers reprimanded over Mount Polley tailings disaster

By ES&E Staff

Eight years after the Mount Polley tailings disaster, three engineers have been penalized, following disciplinary proceedings by Engineers and Geoscientists British Columbia.

The regulator said it reviewed thousands of documents over the multi-year investigation, including contracts, technical reports and drawings, correspondence, and daily site reports from the August 4, 2014, incident at the former open pit gold and copper mine. Ultimately, it issued penalties to former engineers Todd Martin and Stephen Rice, who stopped practicing in 2018, as well as junior engineer Laura Fidel, who was suspended for two months.

The incident resulted in more than 17 million m3 of water and 8 million m3 of tailings effluent, containing toxic copper and gold mining waste, leaking into Polley Lake, Hazeltine Creek and Quesnel Lake from the mine’s tailings storage facility.

“This marks the final chapter in a long and difficult story for our province and our professions,” announced Heidi Yang, CEO of Engineers and Geoscientists British Columbia, in a statement. “Over the past several years, our focus has been on delivering a comprehensive, rigorous, and fair process, and we’re pleased to be able to provide the public with these results. The conclusion of these cases, combined with resources we’ve developed to improve dam safety, will strengthen our professions and our province’s environmental safeguards,” she added.

The tailings storage facility’s embankments had been built to a slope of 1.3:1, which by all accounts was unusually steep for a rockfill tailings embankment constructed on a soil foundation, the panel found.

Rice shouldered the majority of the blame in the proceedings due to unprofessional conduct that saw him leave Fidel, a junior engineer quite inexperienced with embankment design, to act as Engineer of Record for a very complex storage project. Rice, who had never faced disciplinary action before, then failed to ensure sufficient observation and monitoring of the tailings dam, failed to document his review work, and failed to ensure an excavation left unfilled at the toe of the embankment was assessed to determine what impact it may have on stability.

Martin was the senior geotechnical engineer on site. The proceedings found that he failed to recommend drilling from the 2011 embankment crest into soils under the footprint of the tailings storage perimeter embankment. This would have improved the characterization of embankment foundation soils, the regulator said.

Fidel was penalized for failing to ensure sufficient observation and monitoring of the tailings dam while acting as

The Mount Polley tailings storage facility’s embankments had been built to a slope of 1.3:1, which by all accounts was unusually steep for a rockfill tailings embankment constructed on a soil foundation.

Credit: Mount Polley Mining Corporation

Engineer of Record, failing to ensure sufficient site visits, and failing to monitor seepage flows that could reveal potentially unsafe conditions within the embankments.

However, the regulator clarified that it has not “alleged any link or connection between Ms. Fidel’s professional conduct and the cause of the perimeter embankment breach.”

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