Mount Polley Community Update Q3 2021

Happy fall everybody. Our team at Mount Polley hopes that this finds you well.

Things at the mine continue to get busier as we prepare for a mine re-start along with our routine care and maintenance activities. We have had many visitors to the site over the past few months, most of whom were contractors conducting work for the mine, but we have also offered several open-air tours covering various aspects of the mine. As we move closer to the end of the pandemic, we look forward to offering more opportunities for community engagement and more in-person tours.


Below we cover key bulletins that highlight areas of focus with regards to Mount Polley mine’s care and maintenance:

  1. The environmental monitoring
  2. Closure research projects continue programs continue and are on track as planned
  3. Site water management continues, including the near-continuous operation of the water treatment plant
  4. CANMAG plant maintenance and upkeep
  5. Lower Hazeltine Remediation area continues to be monitored and maintained


Quarter 3 routine monitoring activities completed:

  • Weekly Water Treatment Plant (WTP) water quality sampling including monthly/quarterly toxicity sampling
  • Monthly water quality sampling at Hazeltine Creek
  • Monthly & Quarterly water quality sampling of surface & mine affected waters including groundwater mine seepage
  • Flow monitoring
  • Polley Lake, Bootjack Lake, Quesnel Lake water quality sampling
  • Water quality sampling and monitoring of in pit treatment at Springer and Cariboo pits
  • Monthly/quarterly site inspections
  • Reporting—monthly, quarterly, annual
  • Specialized monitoring components including plankton, Polley Lake fish population, fish tissue, habitat characterization, wildlife
  • CEMP development/revision

Environmental monitoring is conducted in accordance with the Environmental Management Act (EMA) Permit 11678, Metal and Diamond Mining Effluent Regulations and the approved Comprehensive Environmental Monitoring Plan (CEMP) requirements.

Figure 1 Newly installed H2 hydrological monitoring station.  The original station was removed to facilitate instream remediation
Figure 2  Lynx observed near Hazeltine


In Quarter 3, the total treated water discharged to Quesnel Lake was ~1,882,460 mᵌ with an average discharge rate of ~0.243 mᵌ/second and an average of ~20,462 mᵌ/day.

The plant operated continuously for most of Quarter 3.  Water quality samples were collected weekly at the Water Treatment Plant (WTP) influent (E19) and effluent (HAD-3) sites throughout the quarter.


Instream construction in Hazeltine and Edney Creeks was completed and finished in Q3 2021.  The work marks an important milestone for the remediation project, all instream work is now completed.  The work was completed in time for the annual salmon migration in the region and salmon did arrive in Hazeltine Creek in mid-September.  A total of 206 sockeye salmon were observed on September 22 and the fish appeared to be using the habitat as intended.  The presence of sockeye salmon and various other fish species is indicating that the remedial work is restoring ecological function.  This is not only evident in the aquatic environments but also evident across the terrestrial landscape where plant communities are developing and abundant wildlife is observed.  It is expected that as both the aquatic and the terrestrial ecosystems mature, further ecological functions will emerge and the site will host an even broader array of organisms.

There is still outstanding terrestrial remediation work to be done.  Planting will resume next spring to address the disturbances created by the 2020/21 construction.  Earthworks are planned for several small areas within the Hazeltine Creek corridor and the Polley Lake shoreline.  Future planned work will involve recontouring existing topographical features, planting, and monitoring.

Figure 3  Sockeye salmon in Hazeltine Creek above the Ditch Road bridge


Hazeltine Creek Remediation Wildlife Monitoring Plan Update

A Wildlife Monitoring Plan has been implemented in the Hazeltine Creek corridor, utilizing wildlife cameras to build an inventory of animals that are using the corridor to support local wildlife studies.

Environmental monitoring programs and closure research projects at Mount Polley mine site have successfully reached several milestones since inception in 2014. Post-remediation monitoring in lower Hazeltine Creek and Edney Creek have reported significant improvement in water quality to promote increased aquatic habitation. All areas that were disturbed by the 2020 construction near Hazeltine and Edney Creek were seeded with a variety of local, non-invasive vegetation comprised of Mountain Brome, Native Red Fescue, Rocky Mountain Fescue, Bluebunch Wheatgrass, Blue Wildrye, Fireweed, and Big Leaf Lupine. This selective plant growth not only helps re-introduce wildlife usage in the area but, creates a suitable habitat for a diverse range of wildlife activities from nesting birds to foraging and predator/prey interactions. To better understand the impacts and implications of these programs and remediation efforts on Mount Polley as well as potentially other mine sites, specialized wildlife cameras have been installed for mammal species monitoring. As a result, an inventory of identified species including numerous bird species and even some large insects within the Hazeltine Creek corridor by remote cameras have captured a library collection of raw footage.

The gallery below offers a preview to the library of photos retrieved by on-site staff.

In addition to creating a mammal inventory, the study was also intended to identify whether wildlife usage was negatively impacted following the dam incident. However, review of the current inventory suggests that usage was not impaired. On the ground, staff are also seeing a prevalence of locally known mammal species such as bears, mule deer, and moose.

Although it is a little too early to confirm any trends, photos of wolverine, which are quite uncommon in the area, also suggests that the remediation efforts have potentially created an environment that is becoming well received by a more diverse group of terrestrial lifeforms and continues to be home to the local ecosystem entirety.

The team will continue to conduct non-intrusive, wildlife research monitoring to better understand local animal activity and behaviour. Everyone on site shares their wildlife observations with staff, which are recorded in a wildlife tracking table. Mount Polley’s team are committed to completing the in-stream work this year as well as the remaining terrestrial remediation within the next two years. Updates on the remediation work at Mount Polley mine are available in the quarterly Community Update newsletters on


Over 100 sockeye salmon adults return to spawn in Hazeltine Creek

After seven years of remediation work in Hazeltine Creek in response to the 2014 tailings dam breach, the salmon have returned to the creek to spawn.  In stream work was completed in late August this year, just in time for the sockeye migration in the region.

In the early stages of the Mount Polley remediation effort, 40 thousand truckloads of rock were used to build a foundation channel along Hazeltine Creek from Polley Lake to Quesnel Lake. Next, section by section, the remediation team modified the initial channel and added sinuosity and habitat features to provide instream cover for fish, enhancing the habitat value. These features included spawning platforms, pools, riffles, rock boulder clusters, root wads, and logs.

The biological design for habitat features was developed collaboratively with Mount Polley’s technical experts, Williams Lake First Nation, Xatśūll First Nation, and at the regulatory level, with the Department of Fisheries and Oceans and the Ministry of Forests, Lands and Natural Resource Operations.  Collectively the group is referred to as the “Habitat Remediation Working Group.”

Over the past few weeks over 100 sockeye salmon adults have returned to Hazeltine Creek to spawn. “The focus of the Hazeltine Creek remediation effort at Mount Polley has been to repair and rehabilitate Hazeltine Creek so that it becomes a self-sustaining, productive fish habitat.” said Brian Kynoch, President of Imperial Metals. 

Trout have been using portions of the rehabilitated creek to spawn since 2017, and now another major milestone has been achieved with the return of sockeye salmon to the creek. The presence of the sockeye salmon and various other fish species signals that the remedial work has begun to restore ecological function.  This is not only evident in the aquatic environment but also evident across the terrestrial landscape where plant communities are developing, and abundant wildlife is observed.  It is expected that as both the aquatic and the terrestrial ecosystems mature, further ecological function will emerge, and the site will host an even broader array of organisms.