Yukon minister confirms leak at Eagle Gold mine, warns creek could see more impacts

The Yukon's mines minister has confirmed toxic water at the Eagle Gold mine is escaping one of its newly-built storage ponds.

"There's definitely a leak," said Minister John Streicker, adding the cause remains unclear.

"As that water has been leaking it will get down into Haggart Creek, and we could see the evidence of that."

Haggart Creek has become the bellwether of environmental impacts since part of the mine — where cyanide is used to process ore — failed last June with a massive rockslide. Since then, contaminated water has been leaching into the environment. The latest publicly-available government data shows cyanide in the creek has been high enough, at times, to kill fish.

The storage and treatment of contaminated water has been a serious issue since the mine failure happened, with hundreds of millions of litres of cyanide-contaminated water now being held in storage ponds at the site. That volume of stored water continues to grow. 

On Tuesday, a spokesperson with the Yukon's Department of Energy, Mines and Resources told CBC News that an estimated 17,000 cubic metres — equivalent to roughly seven Olympic-sized swimming pools — may have leaked out of storage already. But that estimate is based on crews eyeballing water levels in the storage pond and it remains unknown just how much water the pond is losing.

A departmental spokesperson said other issues could be affecting levels like the formation of ice.

Bill Slater is an independent environmental consultant, who's working with the First Nation of Na-Cho Nyäk Dun. He says that whatever bad water is seeping out is sure to compound environmental impacts.

"The 17,000 cubic metres is a substantial amount of leach solution to put into groundwater — but of course, it pales in comparison to the amount of leach water that's been dumped into the ground for the last six-and-a-half months."

The First Nation, whose traditional territory is affected, remains most concerned with effects to the groundwater, which, unlike water on the surface, continues to move.

The mine's receiver, PricewaterhouseCoopers, has launched an investigation to ascertain what's happened with the leaking storage pond.

Streicker said finding and stopping the leak hinges on emptying everything — water, ice and snow — out of the pond. 

But with storage capacity already critically limited, it has remained unclear where all that contaminated water would go.

"We don't have extra storage around the site," Streicker said.

The good news?

The now-upgraded water treatment plant at the mine site is now able to neutralize stored cyanide, said Streicker, who called this the solution to on-site problems. But there's a catch. The plant is using copper — also toxic — in that process.

"Then it's leaving this total copper in the water," he said, "so they need to build a small settling pond right beside the water treatment plant."

Streicker said this needs to happen before treated water can be discharged into the environment, which could start to happen later this month.

Work to build a settling pond will happen during the next couple weeks, he said.