Underground stabilization work

In order to reduce risks at the Giant Mine site, underground stabilization work is required. The work will be done in two phases: from September to November 2013 and between the spring of 2014 and winter of 2014.

Concerns and hazards

Some of the Giant Mine site infrastructure, including underground areas, is more than 60 years old. Based on ongoing risk assessments, certain elements require immediate action to reduce risk to on-site staff, the public and the environment.

In the spring of 2013, the Project Team received a water licence from the Mackenzie Valley Land and Water Board to conduct this work. The final work plans and waste management plans were then developed and approved in September 2013.

The stabilization parts of the underground will address risks associated underground flooding from Baker Creek and rock collapse or subsidence.

Actions required

Holes will be drilled around the site for a number of reasons. First, cavity monitoring survey equipment will be lowered underground to give exact measurements of the stopes. Monitoring equipment, such as cameras, will also be lowered. Finally, the holes will provide a pathway for a backfill product to be pumped underground. This backfill product will fill the empty spaces and provide stability to the area.

The backfill product will be made mostly from the tailings already on site. A short testing program, to determine the most appropriate mix of tailings and other material (including cement, water and fly ash), will be conducted.

Health and safety

Worker and public safety and preservation of the environment are top priorities for this stabilization work. The work will fall under the purview of existing site-wide emergency and health and safety plans. Ongoing air quality monitoring will be done through the existing site-wide and community network. Additional oversight will be performed by independent third parties.