Mineclosure.com team members provided closure
design services for final closure of the Nanisivik lead-zinc Mine at
73oN in northern
Canada
including the following significant tasks:
Final design, preparation of closure plan and
permitting (2001 to 2003).
Field engineering and construction supervision
(2004 to present).
Preparation of as-built reports and
performance monitoring (2007 to present).
Technical areas of assessment and design included the
following mine aspects:
Talik (thawed zone in continuous permafrost)
assessment within frozen sulphidic tailings.
Cover design for sulphidic tailings and
waste rock.
Closure design for the tailings storage area
including tailings solids, retention dike, by-pass spillway and
water reservoir.
Quarry plans in ice-rich bedrock.
Assessment of mine stability and portal plug
design.
Reclamation covers for tailings and waste rock were
constructed using approximately 1.7 million m3 of locally sourced
granular materials. The objective of the reclamation covers was to
encapsulate the mine waste in permafrost, thereby limiting potential
negative environmental impacts of the waste materials throughout
closure.
The characterization and freezeback assessment for
the tailings talik zone is likely a technical first in the world.
