The federal government has ordered the company that owns the Eagle Gold mine in Yukon to build barriers to protect fish from cyanide-contaminated water after 68 dead fish were found following a discharge of treated water from the site of a massive ore slide.

Cameron Sinclair, a Yukon government fisheries biologist, said at an update Friday that the fish were discovered last week by the mine含羞草研究社檚 owner, Victoria Gold, and they are believed to have died after a release from the mine含羞草研究社檚 water treatment plant.

He said some of the fish were Arctic Graylings and some were Sculpins, and the company has since frozen the dead specimens 含羞草研究社渢o store for later analysis.含羞草研究社�

Sinclair said the company stopped discharging treated water after finding the fish kill, and the federal Fisheries Department has now ordered the company to build seven fish barriers in Haggart Creek to create a 含羞草研究社渘o go zone for fish.含羞草研究社�

The mine was voluntarily shut after the ore was released from the heap-leach facility on June 24, spilling about two million tonnes of cyanide-laced rock.

Yukon含羞草研究社檚 Chief Veterinary Officer, Dr. Mary Vanderkop, said the fish deaths are 含羞草研究社渃ompletely consistent with what we would expect from cyanide toxicity.含羞草研究社�

含羞草研究社淚t kills fish really quickly, and it含羞草研究社檚 also indiscriminate, so any species that come into contact with it, it含羞草研究社檚 rapidly absorbed through the gills, and it interferes with the oxygen process and results, essentially, in rapid suffocation,含羞草研究社� she said.

Vanderkop said 含羞草研究社渋t含羞草研究社檚 exceedingly challenging含羞草研究社� to determine cause of death from cyanide in the animals because the chemical breaks down quickly.

含羞草研究社淭he good part is that cyanide doesn含羞草研究社檛 bio accumulate, so animals or fish that die as a result of cyanide poisoning will not have levels of cyanide in their tissues or in their blood that would represent a threat to animals that might consume carcasses,含羞草研究社� she said. 含羞草研究社淪o, we don含羞草研究社檛 have a concern about this being something that is going to be an enduring problem within the environment, unless there are subsequent releases of high levels of cyanide sufficient to cause additional kills.含羞草研究社�

Brendan Mulligan, a senior scientist with the Yukon Environment Department, said they含羞草研究社檝e found 含羞草研究社渃lear evidence含羞草研究社� of groundwater contamination, though samples with the highest concentrations of cyanide, up to 10,000 times above aquatic life guidelines, are being 含羞草研究社渃ontained on-site.含羞草研究社�

Mulligan said the company含羞草研究社檚 discharge of water from its treatment plant earlier this month to nearby Haggart Creek also resulted in samples showing cyanide levels above guidelines for aquatic life.

He said his department has spent 含羞草研究社渆normous amounts of energy含羞草研究社� on the disaster at the Eagle Gold mine, which is located about 400 kilometres north of Whitehorse.

Dr. Sudit Ranade, Yukon含羞草研究社檚 chief medical officer of health, said the groundwater contamination on the site isn含羞草研究社檛 a threat to drinking water.

含羞草研究社淭hese are separate systems, and so at this time, the drinking water system that is regulated is still not at risk,含羞草研究社� he said.

Yukon officials said they are still collaborating with the Na-Cho Nyak Dun First Nation, whose territory the mine is on, and technical experts as cleanup of the disaster site continues.

The First Nation has called for a moratorium on mining on its territory since the disaster, but Yukon Premier Ranj Pillai said earlier this week that the prospect of halting mining as requested has 含羞草研究社渟ignificant legal and economic consequences.含羞草研究社�

含羞草研究社淭he consequences of such action would be significant, with serious and far-reaching consequences for all Yukoners,含羞草研究社� Pillai said in a statement released Aug. 5.

He said the government is 含羞草研究社渘ot prepared to halt all existing, permitted mineral development activities,含羞草研究社� but has since agreed to a temporary two-month pause on 含羞草研究社渆xisting consultation processes含羞草研究社� for new mining licences on the Na-Cho Nyak Dun territory.

含羞草研究社� By Darryl Greer in Vancouver

The Canadian Press