Abstract
Sublevel retreat (SLR) and sublevel cave (SLC) production levels require an initial void for production drifts to begin blasting into. Slot drifts are commonly developed perpendicular to production drifts and used to establish a free face using uphole drilling and blasting. Unlike in open stoping, these openings are filled with caved or blasted material, requiring choke blasting. The overall approach of establishing these slot drifts is relatively straightforward from a high level, operationally there are many options to achieve this. It is important to understand the impact these options have on safety, ore recovery, and production rates. Diavik Diamond Mine uses SLR/SLC methods to mine two ore bodies. During the last 10 years of production, seven different methods have been used to open and establish slots in SLR/SLC levels. This paper examines the various methods used and their suitability to different situations. The methods used at Diavik are heavily dependent on ground conditions and what the ore quality will allow. The work completed at Diavik may offer a starting point for other mines beginning or changing an SLR or SLC.