Government of Yukon provides update on water and fish monitoring offsite of Victoria Gold’s Eagle Gold Mine

Yesterday, the Department of Environment’s Senior Groundwater Scientist Brendan Mulligan and Senior Fisheries Biologist Cameron Sinclair provided an update on water and fish monitoring offsite of Victoria Gold’s Eagle Gold Mine. In addition, Chief Medical Officer of Health Dr. Sudit Ranade provided an update on human health recommendations for recreating in the area.

Website launch:

• The Government of Yukon has released an online hub with current information on the Victoria Gold Eagle Gold Mine heap leach failure. Up-to-date information about the ongoing incident and response is now readily available at http://yukon.ca/victoria-gold-updates.   

Environmental monitoring:

Water sampling results:

• Daily sampling is underway at most of the surface water sampling locations, with more results coming in every day.
• Monitoring efforts are based on the water monitoring and reporting plan that has been developed by the Water Resources Branch, with technical experts from First Nation of Nacho Nyak Dun, representatives of the Government of Canada, other Yukon government departments and consultants in response to the heap leach failure at the Eagle Gold mine site.
• The water samples are being screened for various forms of cyanide, heavy metals and other contaminants.
• Laboratory results shared on August 1 are from samples collected up to July 24, 2024.
• Samples collected from monitoring station DG1 in Lower Dublin Gulch show concentrations of weak acid dissociable (WAD) cyanide that significantly exceed aquatic life guidelines.
• Samples collected from two stations on Haggart Creek, downstream of Dublin Gulch (W4-mix and W29) on July 24, 2024, show levels of WAD cyanide that are modestly above aquatic life guidelines.
• The aquatic life guideline for cyanide is 0.005 mg/L. When this guideline is exceeded, aquatic life is at risk of suffering acute or chronic adverse effects.
• WAD cyanide results from samples collected at site W99 or further downstream did not exceed aquatic life guidelines.
• Test results showing lower levels of cyanide further downstream in Haggart Creek are due to the dilution of cyanide in the water.
• None of the samples collected from any of the monitoring sites have exceeded drinking water guidelines for cyanide (0.2 mg/L).
• Monitoring of water flows and aquatic insects has been added to the monitoring program.
• Groundwater sampling is part of the Department of Environment’s monitoring plan but has not been implemented in recent weeks due to monitoring sites being located in the mine site’s exclusion zone. Groundwater monitoring at these sites will resume when it is deemed safe to do so.

Fish monitoring:

• Offsite fish monitoring work is being conducted with technical experts from First Nation of Nacho Nyak Dun and the federal Department of Fisheries and Oceans.
• These efforts include monitoring the short- and long-term effects of the heap leach incident on fish populations in the Haggart Creek Watershed.
• This work is being conducted at over 50 locations, 21 of which were previously assessed in 2010, allowing for detections in changes and determining potential long-term effects.
• Fish exposed to cyanide can suffer from both acute and chronic effects, at all life stages.
• Acute, or short-term effects of cyanide over the aquatic health guidelines can be fatal to fish. Chronic or long-term effects can include:
  • Changes in fish abundance;
  • Changes in the growth rates;
  • Movement patterns of arctic grayling;
  • Changes in fish habitat; and
  • Determining the levels of heavy metals accumulating in fish tissues over time.
• To date, assessments have been completed at 47 monitoring sites, with five sites being inaccessible due to being on the mine property.
• Recent heavy rains, weather and environmental conditions in the area have stalled some sampling efforts due to the turbidity of the water and not being able to recover fish.
• To date, the Department of Environment has collected approximately 65 arctic grayling and 50 slimy sculpin, which the Department’s Animal Health Unit is submitting to an approved laboratory for analyses that includes determining heavy metal contamination.
• As of now, the Yukon government has not yet observed any dead fish downstream in the receiving environment.
• Dead fish were reported to be found on the mine site following the incident. Those fish have been sent to Environment and Climate Change Canada for tissue analysis and the Government of Yukon is awaiting results.

Health update:

• The Yukon’s Chief Medical Officer of Health Dr. Sudit Ranade and the Yukon’s Chief Veterinary Officer Dr. Mary Vanderkop released the following statements regarding hunting and recreation activities in the vicinity of the Victoria Gold Mine site: https://yukon.ca/en/news/statements-regarding-hunting-and-recreation-activities-vicinity-victoria-gold-mine-site.