Residents affected by dam failure hope to see action against miner

Residents who live near the Mount Polley mine hope an expert engineering panel’s findings provide ammunition for the province to take action against Imperial Metals over the collapse of its earth-and-rock dam.

Millions of cubic metres of water and finely ground rock containing potentially toxic metals, commonly called tailings, were released into the Quesnel Lake watershed on Aug. 4 when a section of the dam failed.

In releasing its report last Friday, the panel stopped short of assigning any blame for the dam failure on Imperial Metals, but listed a number of contributing factors in addition to finding the root cause was a design failure in the foundation.

“The (panel) couldn’t point a finger, but they came with a lot of information that allow others to point a finger,” said Richard Holmes, a biologist who lives in Likely near the mine dam failure.

He and more than 100 other area residents attended a meeting Friday afternoon in the community to hear the panel’s findings and ask questions.

“Everything was to the fine line. There were so many things they pushed the limits on — it finally caught up with them,” said Holmes, who does work for the Soda Creek Indian Band.

The panel, in fact, noted it was “disconcerted” to find that while the dam failed because of an undetected weakness in the foundation, it could have failed by overtopping — which it almost did — or it could have failed from internal erosion, for which some evidence was discovered.

“Clearly, multiple failure modes were in progress, and they differed mainly in how far they had progressed down their respective failure pathways,” observed the panel, chaired by University of Alberta professor emeritus Norbert Morgenstern.

Concerns raised by the panel include building the dam at a steeper slope than originally designed, which also prevented water pressure instrumentation from being placed in the failed section.

The tailings dam was designed by Knight Piesold in the late ’90s and AMEC took over as the engineer for the facility in 2011. The panel also pointed to the tremendous amount of water stored in the dam, which made the damage worse, and cited an overtopping incident in May 2014. The spill was among the largest in the world in the past 50 years.

There are two other investigations underway — by the B.C. Conservation Service and the B.C. inspector of mines office — that could result in legal charges or fines.

Imperial Metals could not be reached for comment Sunday and Monday.