Remediation Plan

The Giant Mine Remediaton Project addresses the long-term containment and management of the arsenic trioxide waste, the demolition and removal of all buildings on the surface, and the remediation of all surface areas including the tailings ponds. It also includes water management and treatment options.

An aerial view of the buildings, tailings ponds and road network at the Giant Mine site near Yellowknife, NWT

The Remediation Plan was developed after years of site investigations, research and extensive consultation with the public and with the Independent Peer Review Panel. From a possible 56 different management alternatives for dealing with the arsenic trioxide waste, the list was narrowed down to the 12 most viable options.

Following this extensive community consultation period, the 12 options were further refined to two options: one which would keep the arsenic trioxide waste in the ground ("leave-in") and another which would involve removing it and storing it above ground ("take-it out"). These two options were presented to the public by the Giant Mine Remediation Project Office at several community meetings and public information workshops.

Based on feedback from public workshops, and the recommendations of the Technical Advisor and the Independent Peer Review Panel, the "leave-in" option was selected and the frozen block method was incorporated into the Remediation Plan for Giant Mine.

The Remediation Plan for the Giant Mine site can be broken down into five distinct but interconnected components.

  1. The arsenic trioxide waste stored in sealed chambers and vaults will be contained in frozen blocks.
  2. The surface remediation includes taking down close to 100 buildings, covering four tailings ponds, fencing off eight open pits and cleaning up the contaminated soil.
  3. Water entering the underground tunnels and coming into contact with contaminated material used to backfill mined out areas during the mine's operation will continue to be treated.
  4. Baker Creek, which runs through the mine site, will require some remediation to help restore it to a condition that is as ecologically sound as possible.
  5. After remediation is complete, the site will be maintained and monitored in order to ensure the ongoing protection of human health and safety as well as the environment.

Copies of the full Giant Mine Remediation Plan can be obtained from the Project Office by calling 867-669-2426 or by email.