Mining_Methods_UnderGround_Mining - Mining and Blasting

MelBOurne, auSTralia
High speed haulage at Stawell
keeping on
track
Trucking ore from a depth of one
kilometre beneath the surface can
be a slow and expensive process,
but it’s a thing of the past for the
Stawell Gold Mine in Australia,
where high speed haulage using
a fleet of the latest Atlas Copco
Mintruck MT5010 trucks plays a
major role in the operation. Getting
the ore out involves a long drive
up the sublevel ramps at 1:8 to the
400 m level, and then on an in-
cline of 1:10 to surface, a journey
of 8-9 km. The drivers report that
the MT5010 is the smoothest ride
in all their experience, and the
management is obtaining their
lowest-ever cost/t. The MT5010 is
providing a very good return on
investment!
long history
Stawell Gold Mine, located about 250
km west of Melbourne, was first mined
in 1853. It was closed in 1926, and stayed
dormant for more than 50 years. It then
re-opened in 1982, and has been in
operation ever since.
From 1992 until 2005, Stawell was
owned by MPI Mines, who instituted a
plan to increase gold production from
100,000 oz/yr to 130,000 oz/yr by
end-2006. However, the mine recently
changed hands, and is now operated by
Leviathan Resources, who have adopted
the same objective. To meet these tar-
gets, bench stoping with cemented rock
fill pillars in primary stopes is used.
With this mining method, approxi-
mately 80% of the ore is recovered from
the stopes. Remote-controlled loaders
shift the ore out of the stopes, from where
a fleet of four Atlas Copco Minetruck
MT5010 trucks is employed hauling
it to the surface along a gravel roadbed
maintained by two graders in continuous
operation. Stawell management is
convinced that the MT5010 is the best
truck on the market in terms of load
capacity and performance.
Visual inspection of a Minetruck MT5010 with full load near Stawell portal.
Faster is better
Stawell is a very deep mine with incline
access. Inevitably, the adit is the
bottleneck in the production operation,
because it limits the size of truck that
can be employed hauling ore to surface.
However, within the normal underground
speed constraints, the faster the
trucks, and the cleaner they run, the
greater will be the amount of ore that
gets to surface.
At Stawell, getting the ore to surface
involves an 8-9 km drive, which, even
with the MT5010, involves a round trip
of 100 minutes. On the 1:8 gradient, its
speed under full 50 t load is 12 km/h,
some 2-3 km/h faster than the next fastest
truck on the current market.
This is because the MT5010 has the
greatest power-to-weight ratio of any
truck in its class, giving it the highest
possible travel speeds per tonne.
Based on the success of the site’s
first MT5010, commissioned in 2003,
the mine subsequently ordered another
three, with the latest arriving on site in
early January, 2005. Together, the new
fleet has helped Stawell to its medium
term objectives while reducing the mining
cost/tonne to the lowest it has ever
been.
Comfortable power
The Atlas Copco Minetruck MT5010 is
currently offered with the Cummins
QSK-19-C650 engine as standard. This
underground mining methods 105