Tailings ponds in northern Ontario considered safe, scientist says

A tailings pond breach in central British Columbia this week is raising questions about how mine waste is being taken care of in northern Ontario.

David Pearson says what happened in B.C. is unlikely to happen here

Following a disaster in British Columbia this week, questions are being raised in northern Ontario about the safety of storing mine waste in tailings ponds. Pictured here are tailings ponds in Sudbury, Ont. (Yvon Theriault/Radio-Canada)
An area of British Columbia is under a state of emergency after the wall of a tailings pond collapsed. Could that happen here. The CBC's Olivia Stefanovich put that question to a professor at Laurentian University. 5:36

A tailings pond breach in central British Columbia this week is raising questions about how mine waste is being taken care of in northern Ontario.

The recent disaster at the Mount Polley Mine released billions of litres of wastewater into river systems.

But, according to Laurentian University professor David Pearson, the tailings ponds here in the North often aren't built at all.
Laurentian University Earth Sciences professor David Pearson. (Megan Thomas/CBC)

They're existing lakes or wetland — and that's what makes them safer.

"It's not like a pond on a parking lot where a break would cause a massive flood,” Pearson said.

Even so, companies that want to mine in Ontario must prove they can rehabilitate a site or pay for a cleanup before they begin production.

And the Ministry of Northern Development and Mines makes inspections every few years.

Former Glencore scientist Lisa Leger said Ontario has strict protocols to prevent what happened in B.C.

"I was heavily involved in risk management and know that the companies will definitely listen to all the concerns."

You've probably heard about the tailings pond leak in British Columbia. We hear about a historic spill in northern Ontario and talk with an expert about where exactly tailings ponds can be found around here, and what's in them. 9:08

But environmental groups like Mining Watch Canada remain skeptical that full-site rehabilitation after such a disaster is ever possible.

The Canadian program co-ordinator with Mining Watch Canada said there are always risks associated with storing massive amounts of tailings.

“Regardless of how responsible a company is, up until a point where there's a breach ... there's little they can do once that happens to prevent the tailings from, from moving downstream,” Ramsey Hart said.

Comments

To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.