of specialist skill positions yet to be filled. In addition to acquiring the necessary skills at the senior
and middle management level, the development of mechanised mining skills was highlighted as
a specific and critical requirement for the future success of the mine. As such, a mechanised
mining skills development programme focusing on supervisors, artisans and operators was
implemented and sound progress recorded.
· Fleet and maintenance: South Deep instituted a number of key strategies to upgrade the
condition of mechanised equipment fleet and effectiveness of its maintenance practices. As part
of the fleet renewal strategy, 58 category 1 units have been commissioned over the past 2 years.
The total category 1 fleet currently stands at 111. An expansive and fully equipped underground
workshop spanning a total footprint of 200 metres x 200 metres was commissioned on 93 level to
provide the working conditions necessary for maintenance personnel to perform their tasks more
effectively. Maintenance skills development programmes were introduced to upskill our
engineering personnel. In addition, outsourced OEM maintenance contracts were concluded with
key suppliers (Sandvik and AARD) to effect immediate improvements as our own skills improve
over time.
· Underground working conditions: The new management team identified poor underground
working conditions as a key impediment to turning South Deep into a successful mechanised
mine. A number of business improvement projects were initiated to remediate this deficiency and
focused on various elements of the underground infrastructure, including roadways, water
management, backfill and ventilation.
· Mining method: As an ultra-deep bulk mine, geotechnical considerations and mine design are
critical elements in the overall successful extraction of the orebody. To this end several
improvements in the overall design and mining layouts have been implemented during the past
two years.
- Regional Pillars: The overall stiffness of the regional support design was improved by
reducing the corridor span between regional pillars from 240 metres to 180 metres and by
increasing the dimensions of crush pillars in the destress cuts from 10 metres x 6 metres to
8 metres x 20 metres. Regional pillar width has remained at 60 metres. The design
improvements resulted in lower excavation convergence rates and an increase in overall
rockmass stability.
- High Profile Destress: Over the past two years South Deep converted from a low profile (2.2
metre) destress mining method to a high profile (5.5 metre) layout. This has eliminated an
inefficient and cumbersome multi-step mining process, which included footwall or hangwall
ripping to open excavations for longhole stoping equipment, and enabled mechanised
roofbolt installation. In a significant step for the mine, low profile was completely phased out
in mid-2016. Going forward, all destress development will employ the high profile method.
Significant improvements in 2016
The initiatives that were implemented over the past two years started to yield results during 2016,
which was a milestone year for South Deep. Apart from the 47% increase in gold production to 9.0t
(290koz) there was a continuous improvement in the lead indicators (which we have been providing
the market with for the past two years):
· Development increased by 47% to 6,933 metres in 2016 from 4,701 metres in 2015. New mine
development increased by 9% YoY to 811 metres.
· Given the change to the high profile method in the middle of 2015, destress mining was little
changed YoY at 32,333 square metres (FY2015: 31,499 square metres). The high profile method