An underground LHD with a load of cemented rockfill ready to be dumped in an underground stope at Agnico Eagle’s Amaruq underground mine, part of the Meadowbank mining complex in Nunavut. Courtesy of Agnico Eagle Mines

The mines Betty Lin visited as the global backfill specialist for Hatch often ended up being in areas where the mercury regularly drops below minus 50 degrees Celsius. The rising costs of general use cement—also known as ordinary portland cement (OPC)—and its transportation challenges are affecting backfilling operations at underground mines everywhere, but when permafrost and remote sites are added to the equation, unique challenges arise.