Mining Methods

The Crescent Mine would use an overhand cut-and-fill method, with a new series of stopes started every 50 vertical feet in the veins to allow multiple levels to operate concurrently. In this method, the first stope would be started as a sublevel 10 ft high from a central access point. The sublevel would be driven in both directions along strike to the end of the ore zone or 200 ft away from the access point, whichever comes first. The sublevel would then be backfilled with cemented fill, and a second sublevel would be breasted down on top of the fill. This would continue until the mining of the 5th sublevel is completed. The mine would use three variations of this method, depending on the width of the ore zone and where the ore zone is located in the mine.

The mine plan developed for the Crescent Mine targets the wider and higher-grade ore zones for early development. These zones are located above the Big Creek #4 adit extension between the 3300 elevations and 3700 elevations and are part of the resources known as South Vein-A Block-Lower. To access this area for early production, the Big Creek #4 adit would be extended to the South Vein, and the Countess Decline ramp system extended down to the Big Creek level. These development efforts would proceed concurrently and are scheduled for 12 months of development to access the mining areas. Once the two development efforts are connected, stope access and production can then be started using truck haulage out the Big Creek Portal. The connection of the Big Creek #4 adit with the main ramp system will complete the main ventilation path and secondary escapeway necessary to begin production.