Doornkop is a deep-level single-shaft operation. The operation focuses on narrow-reef conventional mining of the South Reef gold-bearing conglomerate reef. Mining is undertaken to a depth of 2 219m below surface.
Doornkop is a single-shaft operation currently exploiting the South Reef to some 2000m below surface. The narrow South Reef is exploited by means of conventional stoping. Mining of the Kimberley Reef was suspended during FY14 to focus on the build-up of production from the South Reef and to prevent losses as a result of the lower gold price. Mining of the Kimberley Reef may resume should economic circumstances improve sufficiently.
The mining method used is longwall mining with stability pillars on major geological structures. The flat dip, which results in the development of long cross cuts, presents challenges in terms of ore handling, especially for the bottom part of the raises, ventilation and in the long lead times between the start of cross cut development to completion of stoping per raise line.
The mining method used at Doornkop is conventional breast mining, in a sequential grid, also known as sequential grid mining (“SGM”).
Doornkop does not use backfill for the support of stopes. The SGM method makes use of dip pillars and reduced mining spans with pre-developed tunnels, aimed at controlling geotechnical stress. The mining sequence at Doornkop is typically a V-shaped configuration, colloquially referred to as th ........
