Sill pillar recovery at Louvicourt Mine
This paper describes the challenges of mining a sill pillar under various qualities and types of paste backfill. Since 1994, Louvicourt Mine production has been approximately 12.6 million tonnes grading 3.5% Cu, 1.5% Zn, 27 g/t Ag and 0.86 g/t Au. The mining method is transverse blasthole stoping, mining primary and secondary stopes. Production at this 4,300 tpd operation was accomplished using two mining horizons; from the 655 m to 415 m level and from the 680 m to 655 m level. The main sill pillar is between the 680 m level and the 655 m level.
Starting in 2002, mine production will gradually decrease to end the mining operations in mid 2005. Sill pillar production will represent almost 30% of the total mine production in the years to come. The overall recovery of the sill pillar stopes will be discussed in the presentation. To recover the sill pillars, more than 1,500 meters of development is planned, in and under paste backfill. The first sill pillar stopes under paste backfill were mined out in 2002 with excellent results.