January 2016
MODERN MINING
53
DIAMONDS
Top projects
One of the winders being
used in the sinking of the
production shaft. The
permanent winders for
the project – two ground-
mounted Koepe winders for
the production shaft and a
double-drumwinder and a
single-drumwinder for the
service shaft – have been
ordered from ABB.
the blast cover effectively prevented fly rock
from leaving the shaft barrel when the blast
was set off.
In contrast to the vertical shafts, the 6 x 5 m
decline is being developed using standard
methods. “The decline – which, like the
shafts, is being excavated through very com-
petent rock – has thus far progressed smoothly
and we’re now 1,2 km in from the portal,”
Chamberlain observes. “We have, incidentally,
adopted our Australian sister company’s pol-
icy of using highly-skilled machine operators
and we’ve had Australian coaches over here to
assist with training. Part of this training takes
place at Bentley Park and the machine simula-
tors we’ve installed there are bench-marked to
Australian standards.”
The primary mining fleet deployed for the
decline comprises Sandvik machines. Two
Sandvik DD421 twin boom electro-hydrau-
lic jumbos are used for drilling the face and
for rock support and work in conjunction
with Sandvik LH514 LHDs and Sandvik 40-t
capacity underground haul trucks. The aux-
iliary equipment fleet – for example, utility
vehicles, concrete mixers and shotcreters –
includes machines from Getman and Normet.
All the equipment is owned by De Beers but
operated and maintained by Murray & Roberts
Cementation.
Reviewing the progress thus far on the con-
tract and the road ahead, Christoff Kühn says
that the VUP is currently on schedule and
within budget. “We’re pleased at the way the
project is unfolding. Soon we will be in the
full sink mode which will continue through
to 2018 when both shafts will have reached
their final depth, when the focus will move to
equipping the shafts and lateral development,”
he says. “By 2021 – when the open pit will
have reached its final depth of approximately
450 m – we will be commissioning the new
mine and potentially this will be one of the
most challenging parts of the project, as there
is very limited opportunity to overlap open-pit
operations with the start-up of the underground
mine. All the options for the transition are cur-
rently under intensive study with a view to
avoiding a significant dip in production during
the change-over.”
Finally, an interesting point is whether the
underground mine currently being developed
will be the final phase of Venetia. The kimber-
lite resource extends well below the maximum
depth of mining allowed for in the VUP and
there is therefore a clear possibility that the
mine life could be extended even further.
Comments Kühn: “Obviously this is a decision
which is years away and which will be taken
by the De Beers board and its shareholders
at the appropriate time in the light of market
conditions and other relevant factors. What I
can say with confidence, however, is the mine
we are currently creating will be a world-class
operation which assures De Beers’ future in
South Africa for years to come and will pro-
duce diamonds for our grandchildren besides,
if necessary, providing the platform for a fur-
ther extension of Venetia’s life beyond what is
currently envisaged.”
Photos by Arthur Tassell (unless otherwise acknowledged)
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