Minerva Mine in the Fitzroy Basin after heavy rainfall.
The Minerva Mine near Emerald produces 2.8 million tonnes
of export coal a year and one mine was severely affected by
flooding in 2011.
In a letter sent to the Queensland Resources Council in May
2011, the General Manager of Minerva reported that “...the
Minerva Mine received 1.7 metres of rainfall in 2010, with
800mm received in the last quarter. This was three times the
annual average rainfall for the area. The volume of in-pit water
had a significant impact on production and our ability to supply
our premium quality coal to international markets.”
In December 2010, Minerva Mine applied for a TEP to enable
it to discharge accumulated floodwaters. The TEP, accounting
for the increased flow in the river systems, allowed for the
release of waters at higher electrical conductivity (salinity),
accompanied by downstream monitoring, outside the mines
existing environmental authority conditions.
The then-Department of Environment and Resource
Management responded quickly and the TEP application was
approved four days after lodgement.
The General Manager of Minerva Mine personally thanked the
then-DERM staff for the speed with which they carried out the
assessment of the TEP and the help they provided throughout
the process. The TEP resulted in the release of 371.5 million
litres of water into Sandhurst Creek, flowing to the Nogoa
River. The discharge was carried out in compliance with all
water quality specifications and flow limits, as agreed to by
the then-DERM. Under the TEP, Minerva was able to remove all
accumulated flood water and return to full production.
In December 2011, Minerva Mine applied to the then-DERM
to amend its EA to adopt the 2011 Fitzroy model conditions.
The amendment was finalised within the month. Since then,
Minerva Mine has experienced above-average rainfall and
in accordance with the conditions of the EA has made three
compliant releases to reduce accumulated water.
In discussions with the then-DERM concerning the adoption
of the 2011 model conditions within its EA, Minerva Mine was
striving for conditions that were safely within the guidelines
that allowed for the flexible management of discharges
according to varying and significant rainfall events.
ResultBeing subjected to heavy rains in December 2010, and again in December 2011, the Minerva Mine has adopted a Temporary Environment Program model to ensure the release of accumulated flood waters is compliant with all water quality specifications and flow limits.