MiningWatch Shocked by Chief Inspector of Mines’ Report on Mount Polley Disaster

December 18, 2015. Following yesterday’s release of the B.C. Chief Inspector of Mines’ report on the Mount Polley mine disaster, MiningWatch Canada is shocked by the disconnect between the Chief Inspector’s findings and his decision not to lay charges against Mount Polley Mine Corporation (MPMC) for its massive mine waste dam breach in August 2014 – the biggest mine spill in Canadian history.

“How can so many things be done so poorly, sloppily, or haphazardly, and result in massive damage, without someone being ‘at fault.’ It was not an ‘Act of God.’ The report makes it clear that it was poor design, poor practices, poor oversight, and misconduct on the part of Mount Polley Mine Corporation,” says Ugo Lapointe, Canadian Program Coordinator for MiningWatch Canada.

“It makes no sense. Either there were political reasons for the Chief Inspector to not lay charges against MPMC, or the regulatory system is even more broken then we all thought. Either way, it’s not reassuring for any of the mines currently operating in B.C.,” adds Lapointe.

“How can the Chief Inspector conclude there‘s no ground to lay charges while at the same time making dozens of very incriminating statements in his report against MPMC’s very poor practices and standards that led to the failure. It doesn’t add up.”

MiningWatch is also concerned that the Chief Inspector decided not to submit the evidence he had gathered to Crown Counsel. “By refusing to report the case to Crown Counsel, British Columbians are denied the right to know what the Crown Counsel’s assessment of the case would be, including whether to lay charges, and it could very well be much different from the Chief Inspector’s opinion,” says Lapointe.

“We are asking the Chief Inspector and the B.C. government to reconsider this decision and to report the whole case to Crown Counsel,” adds Lapointe.

MiningWatch also points out that the Chief Inspector’s legal analysis is solely and narrowly based on the BC Mines Act and its associated regulations, and not on any other laws or regulations, such as environmental regulations, common law, or professional due diligence requirements.

See below for further details on the Chief Inspector of Mines’ report.

For more information:

  • Ugo Lapointe, MiningWatch Canada (514) 708-0134

Mount Polley Mine Disaster: Excerpts from BC Chief Inspector of Mines’ findings from Investigation Report released December 2015

“...failure of the embankment occurred because of three proximate causes: an uncharacterized glaciolacustrine unit in the native soil foundation of the dam structure; an over-steepening of the downstream slope of the dam, coupled with the constructed height; and an unfilled excavation at the toe of the embankment at the site of the failure...” (p.6)

“MPMC and its engineering consultants did not fully recognize and manage geotechnical and water management risks associated with the design, construction, factor of safety, and operation of the tailings storage facility.” (p.6)

“Adequate studies of the embankment foundation were not conducted on the Perimeter Embankment, and site investigations for the Perimeter Embankment did not meet generally accepted standards of practice for embankment structures. There was an assumed degree of certainty that the foundation soils were dense and strong, which was not supported by a robust understanding of the foundation characteristics.” (p.6)

“Initial site investigations at the Perimeter Embankment foundation did not include adequate geotechnical characterization of soils at depth, and further, no subsequent site investigations were conducted on the Perimeter Embankment until 2011; drillholes were widely spaced and were principally for the placement of instrumentation and the assessment of lower glaciolacustrine soils. (p.6)

“Multiple opportunities to review and characterize the foundation soils arose, either in response to queries by Government inspectors, or available in extant drillcore records; but these opportunities were unnoticed, ignored, and/or discounted.” (p.7)

“An adequate water management plan did not exist. Mount Polley Mining Corporation failed in its management of the water balance with respect to long term planning, including site integration, effective treatment, discharge plans and permits. There was no qualified individual responsible for the water balance, and MPMC did not adequately characterize the risk of surplus supernatant water” (p.7)

“It was the responsibility of Mount Polley Mining Corporation to maintain a safe structure, irrespective of the Mine’s reliance on external geotechnical engineering expertise. Mount Polley Mining Corporation did not meet this responsibility.” (p.7)

“Mount Polley Mining Corporation did not recognize the risk of the excavation for the buttress foundation, resulting in a small reduction in the FoS. This work was not recognized as a substantial departure from the approved work plan by MPMC, and the Chief Inspector was not notified.” (p.7)

“Concerns regarding steep slope, dam construction material availability, buttress subexcavation, and supervision were identified by employees but not elevated for action by MPMC management.” (p.7)