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Mount Polley cleanup underway

LIKELY -- With 24 million cubic metres of water and tailings flushed downstream of the Mount Polley gold and copper mine, the company's biggest challenge now is to keep the remaining tailings and water contained.

LIKELY -- With 24 million cubic metres of water and tailings flushed downstream of the Mount Polley gold and copper mine, the company's biggest challenge now is to keep the remaining tailings and water contained.

There is already considerable concern over the potentially toxic metals released into the environment after the failure of the earthen tailings dam on Aug 4.

The tailings surged into nine-kilometre Hazeltine Creek, which was home to spawning trout and coho salmon, as well as Quesnel Lake, the migration path of more than one million sockeye salmon.

With an estimated 17 million cubic metres of tailings remaining in the storage facility (enough to fill 6,800 Olympic-sized swimming pools), there is urgency in ensuring it stays in place.

Mine owner Imperial Metals must also begin to address the effects of the tailings deposited into Hazeltine Creek and Quesnel Lake.

And with winter rains about to hit soon -- and the deep-freeze of winter around the corner -- the company has little time to waste.

But a plan of attack has emerged and trucks are once again moving on the mine site, although the mine remains closed.

The plan includes blocking the hole in the tailings dam with an earth and rock dike, collecting water that seeps through the dike (which is not waterproof), repairing roads and bridges to create better access to Hazeltine Creek, and probing Quesnel Lake to determine the effect of the spill.

"We think we are making good progress," said Steve Robertson, vice-president of corporate affairs for Imperial Metals.

With the water emptied, the tailings storage facility seems like an alien world.

There are large areas of flat, reddish bare ground -- where only the recent imprints of some large bird mark its surface.

There are also deep valleys and jagged edges carved out by the rush of the water when the dam collapsed.

These type of mine facilities are often referred to as tailings ponds, but this one is anything but a pond.

Like everything at the mine site, the tailings storage facility is big.

At about four square kilometres, the tailings inside comprise finely ground rock that remains after the milling process. They contain potentially toxic heavy metals that are a concern to human health, animals and aquatic life.

It has taken nearly two months, but workers called back after the collapse have completed a 500-metre dike to keep the tailings from washing away in rain or snow melt into Hazeltine Creek and Quesnel Lake.

The earth and rock dike is only a temporary structure, but will be in place until an investigation into the dam failure is complete, and when Imperial Metals has determined how the original dam might be fixed or rebuilt. (Robertson declined to discuss reasons for the failure while the investigation is underway).

The temporary dike is porous, which is why a water collection pond system has been built downstream and another is under construction inside the tailings facility itself.

The collected water from the ponds will be pumped back up to the mine site into one of the large holes dug out to get at the ore, commonly called pits.

The company has also been draining Polley Lake (adjacent to the mine site) with pumps because its level was raised when water washed into it from the dam breach, and the lake's outlet was plugged by tailings.

Enough water has been drained now that it has been deemed safe enough for work to start below the breach in the lower reaches of Hazeltine Creek.

The company and the province were concerned that heavy rains could have released another rush of water, tailings and sediment if the plug had let loose.

Once Polley Lake has been returned to its normal level, a new channel will be created to provide an outlet to Hazeltine Creek.

Work on the collection ponds was visible on a recent tour of the mine site, but Polley Lake and the area below the breach were off limits due to safety concerns.

The Cariboo Regional District has also kept a state of emergency in place to keep the public away from the mine site because of safety concerns.

The general thrust of Imperial Metals' creek rehabilitation plan is to create a series of collection pools along Hazeltine Creek so that sediment can be filtered out before water reaches Quesnel Lake.

The province's environment ministry has not given approval to that rehabilitation plan, saying it must first review data from a series of samples of tailings and sediment taken along the creek by the company.

The original five-metre-wide creek -- scoured by the millions of tonnes of water, tailings, timber and other debris -- is as much as 30 metres wide now and much wider at the delta at Quesnel Lake.

Imperial Metals does not believe it will make sense to remove sediment and tailings from the creek, an expensive proposition that the company says could create more damage.

The company's belief is predicated on its position that the tailings are relatively benign and will not produce acid that would release heavy metals into the environment. While the rock that has been milled in its mine does contain acid-generating pyrite, the acid-generating potential is neutralized by the significant amount of carbonate in the rock, says Robertson.

"It's the same thing when you think of your stomach acid and Tums. Well, we don't have one Tums, we have a whole box of Tums -- so it's a very, very neutralizing environment," he said.

Vancouver-based SRK Consulting, in a 2012 review for the company of years-long lab tests of mine samples, found that it would take decades to produce acid drainage in most of the rock at Mount Polley.

Nevertheless, Robertson acknowledges that continued testing will be needed. "We are going to make sure we do the scientific testing and have the data to be able to demonstrate over a long period of time that things are safe," he said.

The province's environment ministry has also said as much, noting that samples of tailings have shown low but "potentially significant" arsenic and selenium concentration that will need monitoring.

While it's possible it may make sense to leave some tailings in place, others may need to be returned to the mine site, said Hubert Bunce, an environment ministry director appointed recently to head the Mount Polley file.

And while Bunce noted historical data suggests the mine does not have an acid-generating problem, he said one of the concerns is how the material will evolve over time.

"Will it leach in the future? And will that occur in the next year or in the next 10 years or in the next 100 years? And what does that mean for plants, both terrestrial and subaqueous, that may colonize it, and the animals that might eat that?" noted Bunce. "So, that's what the long-term monitoring programs will attempt to ascertain. But obviously it's premature at this point to make any guesses as to what that may be."

There is also the issue of Quesnel Lake.

Imperial Metals does not have a cleanup plan for the lake, or know whether it will be necessary.

To determine what needs to be done in Quesnel Lake, the company is awaiting results from its consultant Tetra Tech EBA, which has a 37-foot research boat on the lake carrying out bottom sampling and water testing, Robertson said.

Tetra Tech EBA is part of a coterie of consultants -- including SNC Lavalin and Golder Associates -- hired by Imperial Metals to work on a cleanup plan.

Bunce said the environment ministry is also waiting for the results of the lake tests.

In the third week of September, in the small community of Likely, the Quesnel River runs almost completely crystal clear.

There is no trouble seeing the green-headed, red-bodied sockeye salmon that appear suddenly, just where the shallow water drops off into darker depths. Schools of about a dozen slip by, tails pumping, on their way up the Quesnel River and on to their spawning grounds in the rivers and creeks that empty into Quesnel Lake.

In just minutes, more than a hundred salmon pass a small dock on the river.

Days before, it would have been much harder to see the salmon, because the Quesnel River was a murky green colour.

This plume of murky water -- created by sediments -- has appeared in the lake and the river from time to time since the dam collapse. (Bunce noted it is evident there is a "cloud" of sediment in the lake that is usually located deep in the water).

It has heightened the fear of some local residents of the long-term effects of the tailings that flowed into Hazeltine Creek and Quesnel Lake.

Despite community meetings hosted by company and government officials, they argue they do not have a clear picture of how the creek and lake might be rehabilitated. Some residents have demanded an immediate cleanup of all the tailings.

These residents also do not trust the test results from the company or the government.

Likely resident Lawna Bourassa said her biggest concern is the delays in getting water quality test results from the environment ministry. For example, test results for Aug. 22 testing had not been posted by the third week of September (Results have since been updated).

The environment ministry said that it can take up to two weeks to post results, and that monitoring is continuing.

Earlier in the month, Bourassa participated in a news conference in Vancouver at the offices of the Union of B.C. Indian Chiefs, bringing with her a jar of sediment-clouded water she pulled from the river.

Because of her lack of trust in provincial and company water tests, Bourassa said she would welcome a university and its scientists being appointed to oversee testing.

"We want answers -- we want to know the water is OK and will remain so," she said.

Bunce noted there is a scientific advisory group that includes experts from the University of B.C., the University of Northern B.C., University of Lethbridge and the University of Ottawa that is checking the monitoring and offering advice.

Likely resident Peggy Zorn, who owns wildlife viewing and hiking company Ecotours B.C. with her husband Gary, said she sees no reason that Mount Polley should not be ordered immediately to suck up tailings that have been deposited in Quesnel Lake with ocean dredging equipment, for example, and put it back at the mine.

Zorn said it's not this year's salmon coming up the river she is worried as much about as next year's juvenile salmon that rear in Quesnel Lake for a year.

Heavy metals could move up the food chain and harm young fish, she said.

Says Zorn: "What's it going to look like next year? Nobody knows."

High above Quesnel River and Quesnel Lake, on a steep, narrow logging road, the human eye can see for dozens of kilometres.

Longtime Likely resident Ken Smith points out the blinking lights in the distance of the Mount Polley mine and its massive tailings impoundment.

Much closer, Smith also points out a placer mining operation. Everywhere, patches of regrowing logged-off timber are visible.

There is little doubt this is an area that has been affected by resource extraction. Just four kilometres from Likely, a three-kilometre long, 120-metre deep canyon was carved out using water cannons during the operation of the Bullion Pit Mine from 1892-1942.

Smith, like other local residents, is not opposed to mining.

But they have nagging doubts that the effects of this dam collapse will not be known for a long time.

Says Smith: "We just don't know. We just don't know."

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