Queensland undermines its own mine policy

Voids, like this one at the Mount Oxide copper mine north of Mount Isa, can be very contaminated and highly saline.

The Queensland Coordinator General has recommended Pembroke Resources' new Olive Downs coal project be allowed to leave three un-rehabilitated pit voids on the Isaac River flood plain after the mine closes.

The decision completely undermines a key element of the mine rehabilitation reforms passed by the Queensland government last year, which promised to ban final voids on floodplains. The government assured the public the reforms would stop mining giants leaving behind contaminated hypersaline pit lakes on floodplains because the environmental risks to precious rivers are too great.

The proposed mine would create 13 open-cut pits over the course of the project. Ten pits would be completely backfilled, but three final voids would be left, covering around 10% of the project site.

Pembroke Resources estimated it would cost $3 billion to backfill the final voids to ground level, making the project economically unviable.

Lock the Gate Alliance Mine Rehabilitation Coordinator Rick Humphries said: "When you have large unrehabilitated voids left at the end of a mine's life on flood plains the chances of flooding are very high risk. Those pit lakes that form, which are very contaminated and highly saline, get this flush of toxic material out into the rivers.

“The decision to let Olive Downs leave three un-rehabilitated pit voids on the Isaac River floodplain is a ticking time bomb that represents a real long-term threat to the river and downstream users.

“We’re disappointed that the Queensland government has failed the first crucial test of its new mine rehabilitation laws. The Coordinator General had the option to require the Olive Downs project to fully protect the floodplain by requiring the pits were backfilled.

“Instead the Coordinator General has backed the company against the interests of the Queensland taxpayers who will bear the long-term environmental cost of the un-rehabilitated voids.

“Every dollar not spent by the mining industry to fix up their mess is a dollar cost to the taxpayer in the form of environmental risk and loss of the value of the un-rehabilitated land. If a mining project can’t afford to return the mined land to a fully rehabilitated state that supports a post-mining land use then it should be rejected.

“We’re calling for the Queensland government to urgently reconsider this decision, and to require the Olive Downs mine to fully backfill and rehabilitate all pit voids consistent with the government’s new rehabilitation policy.”

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