Mount Polley waste water discharge in Quesnel Lake worries residents

A proposal by Mount Polley Mining Corp. to discharge effluent into Quesnel Lake is running into opposition from local residents who say the company is "piling on" to the pollution it has already caused.

Two years ago a catastrophic tailings pond breach at the mine accidentally released 25 million cubic metres of waste water and fine sediment, turning the crystal clear waters of Quesnel Lake a murky green colour for months.

Following the accident, the government gave MPMC temporary authorization to discharge treated and untreated mine site runoff to Hazeltine Creek and Quesnel Lake. But with that permit set to expire next year, the company is proposing a long-term water management plan that would continue to allow waste water to be piped deep into the lake.

MPMC says the effluent meets drinking water standards and won't cause any harm to Quesnel Lake, but residents say the lake's previously pristine quality was degraded by the tailings spill, and continued discharges should not be allowed.

"I guess the biggest concern is the unknown they've already provided us with in the lake and that's the tailings [spill] from 2014," said Richard Holmes, a biologist, local resident and environmental consultant with Cariboo Envirotech Ltd.

"No scientist, including the mine's scientists and consultants, will predict what the impact will be in the future on the fish. And yet they continue to, I guess in sports terms, pile on," he said. "They continue to dump excess water from the site into the lake not knowing the full impact of what they've already done."

After the spill, tests showed slightly higher levels of arsenic, copper, manganese and zinc in fish, but the levels were within human consumption guidelines. The glacial lake, located about 50 kilometres northeast of the city of Williams Lake, covers 266 square kilometres and is renowned for its sports fishery.

MPMC built a $2-million water treatment plant after the tailings pond accident, and the company now says its waste meets drinking water standards, based on lake water samples taken 100 metres from the end of the discharge pipes, outside what is known as the "initial dilution zone."

But Mr. Holmes says that's not good enough.

"We would like them to meet or exceed the receiving water quality. And I don't think that's too much to ask for. All the residents on the lake have to do that. They jump through government hoops to have their own septic systems on their properties on the lake and that requires a lot of effort. I don't think industry should be exempt from that, in fact they should be setting an example," he said.

Dave Danskin, another area resident, said in an e-mail that he's dismayed by the mine's proposal. "The saddest thing … is that there is no acknowledgment of the world famous purity of Quesnel Lake before the breach, which possibly has been lost forever," he wrote.

In a letter released publicly this week, The Concerned Citizens of Quesnel Lake urged government to reject MPMC's application.

"We do not accept the proposal by MPMC that only measures effluent discharge against BC Water Quality Guidelines … after it has been diluted in a massive volume of water," the letter states. "Contaminated water diluted with clean water is still contaminated."

But Steve Robertson, Vice-President of Corporate Affairs for MPMC's parent company, Imperial Metals Corp., said the long-term water management plan does not pose an environmental threat to Quesnel Lake.

"We have the toughest environmental rules and regulations here in British Columbia of anywhere in the world," he said. "And we are going to continue to work within those rules and work with the results as they are provided to us out of the science-based process."

Mr. Robertson said MPMC gathers all the water at the mine site, stores it and analyzes it before releasing it through the treatment system.

"We are actually taking good-quality water and putting it into Quesnel Lake, and we've been doing that for over a year now," he said. "And … that has not had a measurable [water quality] impact on Quesnel Lake."

David Karn, a spokesman for the B.C. Ministry of Environment, said in an e-mail that MPMC's proposal is undergoing public consultation until Dec. 31. He said the government will take all comments into account before making a final decision.

"The Ministry continues to monitor water quality in Quesnel Lake, and we know that water quality in [the] lake beyond the Initial Dilution Zone of the discharge continues to meet British Columbia Water Quality Guidelines," wrote Mr. Karn. "We have data which confirms that BCWQG were being met in the lake very soon after the spill event. In addition, Interior Health continues to re-affirm the water is safe to drink and is safe for both fish and recreation."