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The Mackenzie Valley Environmental Impact Review Board has released a stinging decision on the federal and territorial governments’ proposed remedial plan for the grossly contaminated Giant Mine site in Yellowknife, under s. 128 of the Mackenzie Valley Resource Management Act.

The Giant Mine site is probably the largest, most dangerous, the most expensive contaminated site in Canada. It is located inside the City of Yellowknife. Its underground chambers and stopes contain over 237,000 tonnes of water soluble arsenic trioxide, and there are 13.5 million tonnes of contaminated tailings spread over 95 hectares (approximately 175 football fields).

The remedial plan came from the Giant Mine Remediation Directorate, led by the federal department Aboriginal Affairs and Northern Development Canada (AANDC) and the Government of the Northwest Territories. In essence, they proposed to freeze the ground around the mine “forever”, to demolish 100 buildings and cover the tailings, and to pump partially treated arsenic-contaminated water deep into Great Slave Lake. The Directorate described its plan as:

  • “This is a clean-up the surface project.
  • This is a stabilize and secure the underground project.
  • This is a maintain & monitor for health & safety project.”

The Review Board found that the proposed Giant Mine Remediation Project IS likely to cause significant cumulative adverse impacts, and that significant public concern about the plan was justified. To mitigate these impacts, the Board has ordered the Developer (essentially, the federal taxpayer) to:

  1. Treat the contaminated water to a drinking water standard before it is pumped to the lake;
  2. Reduce the Project timeframe from perpetuity to 100 years, i.e. to find a permanent solution;
  3. Fund and facilitate research in emerging technologies towards that permanent solution;
  4. Investigate long-term funding options, instead of relying on perpetual annual appropriations by Parliament;
  5. Set up a multi-stakeholder group to provide independent oversight;
  6. Do more studies, including a comprehensive risk assessment and human health risk assessment;
  7. Do better monitoring of the impact on human health;
  8. Divert a  nearby creek that sometimes floods the site; and
  9. Hold an independent review of the Project every 20 years to evaluate its effectiveness and decide if a better approach is available.

The federal Environmental Commissioner had already warned that the federal government’s estimate for the Giant Mine site cleanup was insufficient, a factor emphasizing the inadequacy of current financial assurance requirements for ongoing environmental risks. The bigger question is: why did our government allow this disaster to be created in the first place? Especially without financial assurance! What other financial and environmental disasters are waiting to explode in current and proposed resource projects? Is this why the Minister of Natural Resources has finally proposed to increase financial assurance for offshore drilling?

Will we ever learn?

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