Early thaw in B.C. comes as relief for Centerra Gold

‘Is it climate change?’ muses CEO Perry

TORONTO• Climate change giveth, and climate change taketh away — that is, if you can attribute anything to climate change.

Last December, Torontobased Centerra Gold Inc. shut down the mill at its Mount Milligan mine in British Columbia after anemic snowmelt run- off and an unexpected extreme cold snap froze the shallow supply of water in its tailing ponds. On Friday, the company announced that same mill resumed operating at near full- capacity, ahead of schedule, thanks in part to an earlier- than- expected thaw. The company’s stock rose 2.2 per cent to $7.31 per share.

Scientists say that climate change is making water management increasingly difficult because weather patterns are less predictable, but Centerra’s chief executive Scott Perry expressed skepticism.

“Is it climate change? I don’t know. It could be,” Perry said in a recent interview. “We all seem to take liberty to blame everything on climate change.”

This week, the company also announced the tailing pond had thawed earl i er than expected, after predicting this would not occur until April. The mill is currently processing nearly 40,000 tonnes of gold and copper per day, and hopes to ramp it up to 55,000 tonnes during the second half of the year.

His company purchased the mine in October 2016 as part of a $ 1.1- billion deal, in what Perry stressed was an effort to obtain a “lowrisk” mine — at the time, the company was embroiled in disputes with authorities in the Kyrgyz Republic where its other main asset was located. It produces gold and copper and is expected to operate for an additional two decades.

Located about 90 kilometres northwest of Prince George in central B. C., the Mount Milligan mine relies on the snowmelt run- off from the surrounding mountains to fill its tailing pond with water, which is used to process the ore.

The spring of 2017 was one of the driest on record in B.C., Perry said, which was a root cause to the stoppage of the mill last year. Indeed, last year more than 1,000 wild fires ravaged B. C., burning more than 900,000 hectares and setting new records of destruction. This year, however, the snowpack appears to be in line with normal operations, according to Perry.

That’s allayed concerns that the tailings pond will be so shallow it freezes again next year, but Perry acknowledged he isn’t assuming the problem won’t return in the future. In addition to tapping groundwater for its tailing pond, provincial authorities earlier this year granted a temporary permit to draw water from a nearby lake.

That permit expires in October, but Centerra is seeking to extend the permit for the life of the mine, according to company spokesman John Pearson. “We’re trying to make sure we have some mitigation measures in place,” said Perry.

Bethany Coulthard, a hydroclimate scientist at the University of Arizona who studied tree rings in B.C. to develop a historical record of precipitation patterns, said climate change is likely to cause difficulties for water management. She said climate change will have a complex impact on water that is very difficult to predict because it can affect the level and timing of precipitation, which in turn alters whether water is stored as snowpack or not, and also when it melts.

“There’s a fair amount of certainty about projected temperature increases,” she said, “but globally there’s a lot less certainty about hydrology.

“Particularly where is precipitation going to fall and where is it not going to fall ... that’s what impacts humans, do we have water? Do we have too much, and do we have enough?”

Perry said his confidence has been buoyed by the fact that this year’s snowpack is in line with expected volumes.

The mine planners knew that weather patterns would be different at least once every 100 years, he said, adding, “Maybe that ( dry 2017 and cold snap) was the 100-year event.”