Xstrata Copper North Queensland.pdf - Mount Isa Mines

Environmental performance
Case study
Townsville copper refinery’s sustainable
irrigation expansion
The Townsville copper refinery currently uses a sustainable
irrigation method to manage site stormwater runoff and
extracted groundwater.
Captured stormwater is used to irrigate
pastures and produce fodder for cattle.
This water is monitored to ensure it meets
appropriate guidelines. An environmental
assessment was completed in 2009 which
confirmed that the soils across the irrigated
areas have not been impacted and that the
irrigation practices remain sustainable.
This report also reviewed the option of
opening a second irrigation area immediately
to the north of the main irrigation dam. A
key driver for this investigation was to allow
an increase in the land under irrigation,
and to help improve the overall stormwater
management process at the Townsville
copper refinery. Following the investigation,
Xstrata Copper decided to proceed with
the upgrade.
Instead of relying on one irrigator in times of
frequent rainfall events, the new Southern
Irrigation Area has two irrigators that can
work in tandem, which reduces the impact of
plant breakdown. Additionally, the irrigation
pump at the main irrigation dam has been
upgraded to allow more rapid transfer of
water between the two irrigation dams.
Increasing the capacity to sustainably irrigate
Townsville’s copper refinery increases the
ability to capture stormwater for reuse
and decreases the chance of any potential
uncontrolled releases of water and any
resultant soil degradation. The Townsville
region predominately contains sodic soils
which have the ability to erode rapidly
under such events. The current land use for
the irrigation areas is grazing, so good soil
stability is key to sustaining land use into
the future.
“Overall this project allows greater capture
of stormwater while maintaining control
to prevent potential dam overtopping or
unsustainable irrigation during high rainfall
periods where capacity has historically
been stretched and management
needs more intensive,” said Rodney
Cooper – Environmental Advisor at the
Townsville operations.
Xstrata Copper invested $100,000 in the
upgrade which included site preparation and
service roads to allow ease of access during
wet periods. The 2010–11 wet season has
caused some delays in commissioning the
system, which is due for completion in 2011.
Above: New irrigation equipment was installed
at the Townsville coppery refinery
Sustainability Report 2010 109