25 / 56
September 2016
MODERN MINING
23
COAL
Cementation’s involvement at Impumelelo –
which is an entirely ‘greenfield’ project – has
extended well beyond the underground bunker.
“We were appointed in 2011 as the contractor
for the sinking of the two vertical shafts – the
main and ventilation shafts – the mine requires
and also for decline development,” he says.
“The first resources arrived on site in May 2011,
although the formal sod turning and contract
signing only took place several months later
in August. Both vertical shafts have been sunk
to a depth of 200 m with the main shaft being
11,7 m in diameter and the vent shaft 6,5 m.
The decline is 1 000 m long, dips at 17 deg and
has a width of 6,5 m and a height of 3,5 m.
“We commissioned the main shaft in
December 2014 and in January 2015 the first
Continuous Miner (CM) – eventually there will
be 10 CMs – started cutting coal. In August
2015 we commissioned the decline conveyor
to 4 Seam and in the following month the ven-
tilation shaft fans were commissioned. With
the coal bunker having become operational
on 9 June 2016, we are now all but complete
at Impumelelo with the final value of Murray
& Robert’s contract – including the bunker –
being R1,06 billion.”
Turning to the coal bunker, Wells says it was
constructed over a period of a year (starting in
May 2015), with Murray & Roberts Cementation
commissions on schedule
Above:
Isometric view of the
box front structure.
Left:
Coal discharging into
the 1 500-ton capacity bunker.
Note the steel walkway – this
alone weighed 3,5 tons.
Centre:
The box front showing
the feed level (below) and
chute level.
Below:
Chute level of the box
front. Each chute weighs about
4 tons fully assembled.
deploying a team of just under 100 to undertake
the work. Excavation extended over roughly the
first six months with construction – civils and
structural steelwork – occupying the remain-
ing six months. “It was a massive undertaking
and we were under huge pressure to meet mile-
stones but fortunately we were able to meet all
the critical interface dates,” he comments. “I
attribute the success we had to the intensive
planning we put into every phase of the opera-
tion and also the cooperation and support we