Sublevel shrinkage (SLS) is a mining method primarily suited to thick, steeply-dipping or vertical orebodies within a strong and competent host rock of low caveability. Although relatively infrequently utilised, the SLS technique has been applied in Australia in the past (Mackay et al. 2014). SLS is also currently being
implemented at a small number of sites worldwide, including Newmont’s Subika Underground Mine in the Ahafo region of Ghana. In this particular case study, Newmont and Beck Engineering have investigated SLS mining as an extraction method for another gold deposit within Newmont’s resource portfolio. The proposed SLS mine design is almost identical to a longitudinal sublevel cave (SLC). The main difference is the tipping of unconsolidated waste rock backfill into the top of the cave via a system of shafts and an open pit tip-crest.