Tailings water flows at Colomac mine

Dane Gibson
Northern News Services

NNSL (Apr 26/99) - The first stage of crisis management has begun at Colomac mine.

At an NWT Water Board public hearing to renew Colomac mine's water licence, March 2, the ugly truth about the mine's condition was laid out for all to see.

The most immediate problem revealed was that the main tailings pond was two short months away from spilling over the dam.

Royal Oak Mines manager of environmental services, Larry Connell, admits in the recently released public hearing transcripts, that the dam liner holding the tailings water back "was not installed according to the design and is about six feet lower than it should be."

"...Well, because the liner was not surveyed during construction, Golder Associates recommended excavation of the dam crest to confirm liner elevation," Connell said at the hearing.

The excavation that was done confirmed the liner was short, and that something had to be done to avert a major environmental crisis.

"...it is obvious that action must be taken before spring thaw this year to prevent the release of (tailings pond) water to the environment," Connell said in the transcripts.

The company is now in the process of pumping up to two million cubic metres of cyanide and arsenic-laced water from the tailings pond into an unlined, open pit.

Pumping started March 23, an inspection report by DIAND water resources officer, Ron Breadmore, confirmed.

Breadmore said in the report that as of his March 25 inspection, pumping had been continuous for 24 hours. He also expressed concern that there didn't appear to be enough pressure behind the flow.

"Given the concerns over current pump performance, and the possibility of an early (spring run-off), Royal Oak must consider all possible contingencies in the event pumping cannot keep pace with water inflow into Tailings Lake," Breadmore wrote.

Past co-ordinator of the Dogrib Renewable Resource Committee, Violet Camsell-Blondin, has been trying to arrange a site visit for herself and Treaty 11's environmental team.

Camsell-Blondin went to the Colomac site twice before the water board hearing. One of her main concerns is the fact that even before the pumping project began, tailings water was seeping into the environment.

A fact confirmed by Dr. Lain Bruce of Bruce Geotechnical Consultants Inc. in the transcripts. He said when he was at the site in August, he observed seepage coming out of the base of the dam. In 1995, there was no seepage.

"In 1996, there was something in the order of five to six gallons a minute (seeping out of the dam). In 1997, that had jumped up to about 25 gallons, and last year it was up around 150 to 180 (gallons a minute)," Bruce said in the transcripts.

"These are all rule of thumb and approximations and could be out a fair bit, but the trend is for the seepage to increase dramatically. That is not a good sign."

Camsell-Blondin was last at Colomac mine in 1997. She described the effects of the mine on the surrounding environment, located 220 kilometres north of Yellowknife, as "shocking." When she goes back in a couple of weeks, she is prepared for it to be worse.

"The first time I was there, in 1994, the tailings pond was big. When I went back in 1997, there were trees and willows standing in the tailings. I was amazed," Camsell-Blondin said.

"There used to be a road along there and I know because we took it on our tour in 1994. That's now gone, flooded by tailings water."

Camsell-Blondin said the tailings pumping project doesn't quell her fears because of the size of the pond -- which she says is actually a lake.

"It's large, it's very large. This is a big lake," she said.

"My gut feeling is the open pit won't be big enough to hold the amount of tailings water they require to pump down the tailings pond. If it doesn't hold all of it, then we still have a big problem."

When asked about the overall site, she expresses her disappointment that the company has created, and the government has allowed, what NWT Water Board chair Gordon Wray called Colomac "the worst case of an abandoned contaminated mine in the North."

The traditional lands surrounding the site is a known caribou migration route and an area that has been used by Dene and Dogrib for thousands of years.

"Traditional knowledge says the water (from that site) flows all the way to Marion Lake. The cyanide is getting into the water and flowing through our traditional lands," Camsell-Blondin said.

"Everyone is unsure about supporting new industry because of the way the mines have negatively affected the past and are currently affecting the environment. Colomac mine is an excellent example of how true that is."

Royal Oak currently holds a $1.5-million surety bond for environmental reclamation of the site. Royal Oak's own engineering staff estimates the costs of reclamation at the Colomac site at $6.1 million.

Camsell-Blondin said the area has been so devastated that even if all the reclamation is done, it will still be a danger.

"I know it'll be years before anything is even close to being safe. Colomac is going to be like a black hole because you can't use it for anything," she said.