Summary: 1. INTRODUCTION
In the past, the Canadian mine wastes were
stockpiled in tailings ponds designed for this
specific purpose. However, when such tailings
contains sulfide minerals, these react with oxygen
rainwater to form acid mine drainage (AMD). This
acidified water may also lead to the leaching of
heavy metals which can contaminate the
environment. However, because of recent
environmental legislation, mining companies have
the obligation and duty to manage properly the
tailings in order to replace the environmental impact.
In order to achieve this legislation, a new type of
backfill was then developed, namely the paste
backfill, to replace the traditional hydraulic backfill.
This new technology reuse the full size fraction of
the tailings in a mixture with a binding agent (e.g.
ordinary Portland cement, hydraulic minerals, silica
fume, etc) and water (e.g. mine process water,
rainwater, lake water, etc.) to fill underground mine