Photos show 3-D view of Mount Polley tailings spill into Hazeltine Creek, derived from PhotoSat’s satellite topography
(top); and high-resolution satellite view of the breach area. (Photos courtesy of CNW Group/PhotoSat Information Ltd.)
Imperial Metals Spill Tailings in British Columbia
The tailings dam at Imperial Metals’ Mount
Polley open-pit copper-gold mine in southcentral British Columbia suffered a massive breach on August 4, releasing an estimated 10 million m3
of water and 4.5 million m
3of silt into downstream creeks and
Quesnel Lake. The water was not acidic,
and on August 12, British Columbia health
officials declared Quesnel Lake safe from a
human health perspective for drinking
water, personal use, fishing, swimming and
recreational purposes.
However, Imperial Metals’ cleanup
effort will be expensive; and the spill’s negative impact on the company, and to some
extent, on the broader Canadian mining
industry would be hard to measure. The
spill called into question both Imperial’s
tailings storage practices and the diligence
of regulators in assuring the quality of the
Mount Polley dam.
On August 18, British Columbia Minister of Energy and Mines Bill Bennett
announced that independent reviews will be
carried out at every permitted tailings storage facility in the province by December 1.
Also on August 18, the Canadian
Nuclear Commission sent a request to
licensees of uranium tailings facilities in
Canada for them to review the causes of
the tailings dam breach at Mount Polley
mine and confirm that the safety case for
the tailings dam at their facilities remains
valid; confirm and demonstrate that all
necessary operations, inspections, and
monitoring have been conducted in compliance with their licenses and license conditions handbook; confirm that mitigation
measures are in place to mitigate breach
accidents; and report on any identified
gaps and the associated plans to address
them. The commission asked for a
response by September 15.
Numerous news stories in the immediate aftermath of the spill indicated that
Imperial Metals had received warnings
from more than one source that the tailings
dam was being tested to its limits. Among
these, a Canadian news service, Global
News, on August 7 published an interview
with Gerald MacBurney, a former tailings
foreman at Mount Polley, who said he quit
his job in June of this year because he
could not get the support he needed from
management to do his job properly and
make the dam safe.
The Mining Association of Canada
(MAC) issued a statement and backgrounder addressing the Mount Polley
tailings breach in which MAC President
and CEO Pierre Gratton said, “The mining
industry in Canada operates on the basis
of public confidence in sound public policy, effective regulation, and responsible
management practices by companies. The
confidence of the public in what we do and
how we do it is essential. Incidents such
as this are very rare, but it is the goal of
MAC members that they never occur, and
we have been working hard for many years
to achieve this goal. Clearly, we still have
work to do.”
Imperial Metals has placed the Mount
Polley mine on care and maintenance and
in reporting its Q2 2014 financial results
on August 14 said production from the
mine would be lost for an indeterminate
period of time. While the precise costs of
remediation and repair are currently
unknown, the company said it believes
these costs can be managed over time
given the underlying value of its assets and
its access to additional financing.
The Mount Polley mine began operations
in 1997 and, until the tailings dam failure,
had a projected mine life to the end of 2025.
The mine produced 38.5 million lb of copper, 45,823 oz of gold, and 123,999 oz of
silver in concentrates in 2013, and has been
Imperial Metals main source of income. Imperial Metals also has a 50% interest
in the Huckleberry copper-gold-silver mine
in west-central British Columbia and is
developing the Red Chris copper-gold mine
project in northwest British Columbia. In
response to the Mount Polley tailings spill,
members of the Tahltan First Nation who
live in the area of the Red Chris project
blockaded roads accessing the project site,
beginning on August 8, seeking to halt the
project based on fears that what happened
at Mount Polley could also happen at Red
Chris. The blockade was ongoing as of
August 20.
As featured in Womp 2014 Vol 09 - www.womp-int.com