Until 2009, the Mouska Mine was a conventional underground mine, using primarily shrinkage mining to extract the narrow veins that contain its mineralization. As milling occurs at the Doyon Mill site, approximately 4 km away, the use of paste backfill had never been practical. However, upon cessation of mining operations at the Doyon Mine, the paste backfill plant became available for use by Mouska. Because milling operations are temporarily suspended, awaiting batch processing later in 2010, it was necessary to operate the paste plant using tailings retrieved from the tailings pond rather than directly from the mill.
In 2009, a paste backfill system was designed that would allow transportation of dry tailings to the backfill plant and of backfill from the plant to the surface dumping infrastructure (“Megadome”). A borehole from surface to Mouska’s Level 5 allows the paste to reach the underground distribution network. Despite the additional transportation, paste capacity can reach 50 tph. The following paper describes the design and operation of Mouska backfill system.
