Mount Polley mine owner sues engineering firms over tailings dam failure
The owner of the Mount Polley mine in British Columbia’s Interior has sued two engineering firms for damages over a disastrous dam collapse two years ago.
Imperial Metals has filed a lawsuit in B.C. Supreme Court alleging negligence and breach of contract by Knight Piesold and AMEC, now Amec Foster Wheeler.
None of the allegations has been proven in court and neither company has filed a statement of defense.
The lawsuit alleges a flawed tailings storage facility was designed and monitored by Knight Piesold from the late 1980s to 2011, and then by AMEC until its collapse in August 2014.
“Each of the defendants failed to undertake necessary, proper and reasonable investigation of the subsurface conditions underlying the (tailings storage facility) prior to and during its phased construction and operation,” the suit says.
As a result, the suit alleges, the facility had an inadequate safety standard, despite both companies repeatedly providing Imperial Metals with reports that claimed it was safe.
“Those reports were in error,” the suit contends. “The conduct of each of the defendants was negligent, was in breach of the applicable contracts and caused the ultimate failure of the (facility).”
The dam failed on Aug. 4, 2014, spilling 24 million cubic metres of waste and water into nearby lakes and rivers and forcing the gold and copper mine to close until recently.
A spokeswoman for Amec Foster Wheeler said the company could not comment on a matter that is before the courts.
“We continue to work with industry partners, professional organizations and regulators to ensure that the future of British Columbia mining prioritizes safety, accountability, and environmental responsibility,” said Lauren Gallagher in an email.
Knight Piesold did not immediately respond to a request for comment.
B.C.’s mines minister said last month that senior staff had authorized the mine to go back into full production, one year after it was approved for restricted operations.
In January 2015, an independent engineering panel appointed by the B.C. government concluded the dam failed because the strength and location of a layer of clay under the dam wasn’t taken into account during the design process.
The lawsuit was also launched on behalf of the Mount Polley Mining Corp., of which Imperial Metals is the parent company.
The company doesn’t specify the amount of damages sought, but alleges it continues to incur losses as a result of the dam failure, including lost profits, the costs of laying off employees and reduced share values.
The lawsuit says the province has already found the Mount Polley Mining Corp. liable to pay $3.2 million to cover the costs of the engineering panel and spill clean-up, and wants compensation from the two companies.
Another independent investigation into the disaster, led by the B.C. Conservation Officer Service, is still ongoing. The RCMP and federal Department of Fisheries and Oceans are also part of the investigation.
Posted on July 12, 2016 by Sheryl Barr
Source: http://www.theglobeandmail.com, July 8, 2016
By: Laura Kane
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Imperial Metals sues engineering companies over Mount Polley disaster
Government-appointed panel said design failures caused the 2014 tailings dam breach
Andrew Topf
Global TV footage of Mount Polley disaster. Screen shot from Youtube.
It was one of the worst environmental disasters in Canadian history, and now, the company behind the 2014 Mount Polley mine tailings breach is looking to make somebody pay.
Imperial Metals (TSX:III) has filed a lawsuit for damages in the Supreme Court of British Columbia alleging negligence and breach of contract by Knight Piesold and AMEC (now Amec Foster Wheeler), two engineering firms in its employ up to the time when the tailings dam at Mount Polley gold and copper mine collapsed. The suit alleges that Knight Piesold designed a flawed tailings dam and monitored it from the late 1980s to 2011, while AMEC took over the monitoring until the dam's failure in summer of 2014.
The allegations have not been proven in court and neither company has filed a statement of defense, the Canadian Press reported on Saturday.
“Each of the defendants failed to undertake necessary, proper and reasonable investigation of the subsurface conditions underlying the (tailings storage facility) prior to and during its phased construction and operation,” states the suit. “The conduct of each of the defendants was negligent, was in breach of the applicable contracts and caused the ultimate failure of the (facility).”
The tailings dam failure on Aug. 14, 2014, caused an estimated 24 million cubic metres of water and tailings waste to spill into Quesnel Lake and Quesnel River. The operation was closed for nearly a year, before being given a "restricted restart" in July 2015. The event caused the mining industry a black eye in British Columbia and the provincial government was criticized for a lack of oversight.
B.C.'s chief mines inspector said in December 2015 that no charges would be laid by the provincial government due to the failure of the Mount Polley tailings dam.
"The chief inspector found that the mine and its engineers employed weak practices on the mine site and many recommendations go to new standards and guidelines to improve these practices," said the Ministry of Energy and Mines in a news release.
Six weeks later, a government-appointed panel released its findings, which concluded that ". . . there was no evidence that the failure was due to human intervention or overtopping of the perimeter embankments and that piping and cracking, which is often the cause of the failure of earth dams, was not the cause of the breach."
Rather it was design failures that were the main cause:
The breach of the Perimeter Embankment on August 4, 2014 was caused by shear failure of dam foundation materials when the loading imposed by the dam exceeded the capacity of these materials to sustain it. The failure occurred rapidly and without precursors.
Deposited in a complex geologic environment, the weaker glaciolacustrine layer was localized to the breach area. It went undetected, in part because the subsurface investigations were not tailored to the degree of this complexity. But neither was it ever targeted for investigation because the nature of its strength behaviour was not appreciated.
Another contributor was the construction of the downstream rockfill zone at a steep slope. The report's authors said if the downstream slope had been flattened, failure would have been avoided.
According to Canadian Press, Imperial Metals has not specified the amount of damages it is seeking, but alleges it continues to suffer losses from the dam failure.