Operations

Mining Methods

The Company utilizes selective mining methods at both of its mines, including ramp and fill, sub-level stoping and captive cut and fill. Mechanized ramp and fill is the primary mining method used at both mines. However, the most effective mining method is determined based on an analysis of the geological characteristics of each stope, or mining excavation area. Factors considered include the amount of ancillary development required as well as the ore grade and ground conditions expected. The Company determines the appropriate mining method to be used on a stope-by-stope basis, utilizing an engineering and economic analysis.


Ramp and Fill

  • Access to the ore body is a ramp or decline from a footwall lateral.
  • Uses both jackleg and mechanized drills for blasting and load-haul-dump (LHD) mucking machines to haul away ore using an access ramp.
  • Advances in the stope are made in 6- to 9-foot (1.8- to 2.7-meter) increments. After the stope is mined out, it is then backfilled with waste rock and sand to become the floor for the next horizontal stope, moving upward in 10-foot (3-meter) increments.


Sub-Level Stoping

  • Utilizes a ramp along the footwall of the reef to allow access to the ore body at 25- to 40-foot (7.6- to 12.2-meter) vertical intervals.
  • Ore is removed from the open stopes using a remote-controlled LHD vehicle.


Captive Cut and Fill with Bore-Hole Access

  • Access to the ore body is from a footwall lateral to a cross-cut, and then pulling a raise bore, level to level, for access to mining stopes.
  • Horizontal slices are mined using jackleg drills and blasting. Ore is transferred to an ore pass using a slusher and a slusher bucket.
  • Following completion of the first lift, access to the next level is from the top of the raise.


Captive Cut and Fill with Alimak Access

  • Access to the ore body is from a footwall lateral to a cross-cut, and then driving an Alimak raise from level to level for access to mining slopes.
  • Horizontal slices are mined using jackleg drills and blasting.  Ore is transferred to an ore pass using a slusher and a slusher bucket.
  • Following completion of the first lift, access to the next level is from the top of the raise.