Toxic mine water released during QLD flooding

Widespread flooding in Queensland has created a major problem for the state's mining industry.

The last week has seen record rain fall across much of central Queensland and around 20 mines are discharging water into local rivers with the permission of the Queensland government, ABC reported.

There has also been an uncontrolled release of water from the highly toxic decommissioned Mount Morgan gold mine.

Closed in 1981 the mine is located about 40 kilometres south of Rockhampton on the Dee River and is currently managed by the state government.

Michael McCabe, the coordinator of the Capricorn Conservation Council said it contains highly acidic water.

“Well, some have compared the acidity of that water to close to battery acid,” McCabe said.

It is estimated that about 700 mm of rain has fallen over the Mount Morgan mine site since last Wednesday.

The deluge has caused the mine’s open cut pit to overflow since Saturday morning at a rate of about 60 megalitres a day.

The Queensland government said strong water flows through the Dee River have significantly diluted the untreated water and minimised potential downstream impacts.

But McCabe argues that this is an ongoing issue.

“The rate at which we treat this water in these legacy mines, for years since [they] closed, is not good enough and events like we’ve just seen are likely to exceed the capacity of our holding systems and our capacity to stop these uncontrolled discharges,” he said.

Controlled water releases

Four coal mines in the Fitrozy Basin have released stored mine water as heavy rains inundate central Queensland.

The releases are the first in a pilot program of controlled mine water releases.

QLD minister for environment and heritage protection, Andrew Powell, explained that the deluge from cyclone Oswald had provided enough stream flow for BMA mines to release their water.

“This is the first release from BMA mines since the Government announced the pilot program in November 2012,” Powell said.

“All four mines participating in the pilot, Goonyella Riverside, Peak Downs, Norwich Park and Saraji have now commenced releases in accordance with their environmental authorities, with releases beginning at 5am this morning.

“The Department of Environment and Heritage Protection has been advised of these releases and is monitoring them closely.

“Currently all data suggests that the water quality in Rockhampton is well and truly within acceptable levels.”

Despite the strict environmental conditions imposed on mining companies regarding the controlled release of water, there is a lot of community concern.

In 2008 local water supplies were contaminated when the Labor government allowed a massive water release from the flooded Ensham mine.

Ian Burnett, the general manager of AgForce, which lobbies for the interests of Queensland’s farmers, said the release was to the detriment of nearby farms.

“It [the river system] is the lifeblood for quite a few communities in Central Queensland, and also there’s irrigation, there’s stock and domestic, all the way down to, um, Rockhampton and beyond,” Burnett said.

“So it is a significant river system for that region.”

AgForce has already raised its concerns with the Queensland government.

Burnett said he’s not confident in the processes that have been put in place to protect the waterways and local landholders will be watching the pilot closely.

“We’ll have members who are going to be very close to where these releases are in the pilot and we'll certainly keep the government informed as we get information from those members,” Burnett said.

McCabe agrees, saying he is concerned about the accuracy of government monitoring programs.

“One of the questions we’ve got and we haven’t got an answer yet, is whether or not the data is available, given we’ve had a lot of communication gaps in Central Queensland,” McCabe said.

“In the past we’ve often become aware that a lot of the gauging stations for water quality and flow can be submerged in record flow events. We’ve got a meeting with the Fitzroy Water Advisory Group coming up in a week or so time, where we’ll have many questions and debates about how much new water arrived in mines, how much was discharged—and the big question which we never quite get a good answer on is what are the ecological impacts.”

Michael Roche from the Resources Council said many lessons have been learnt from the 2008 Ensham mine water release.

“One of the biggest problems we had in 2008 was that the water discharges were allowed to occur well into the dry season,” Roche said.

“This won’t happen this time. We’ve learnt the lessons of 2008. What happened in 2008 was with the approval of the regulator, but the thinking and the science has improved a lot since then.”

Environment groups are also worried about the potential for further contamination of the Fitzroy Basin, Australia’s second-largest coastal draining catchment.

Nigel Parratt, from the Queensland Conservation Council, says the water released last Friday from the BMA sites is also likely to contain far worse contaminants than salt.

“With the length of time that this water, which is now described as legacy water, has been in some of those coal mines, it’s been exposed to a whole range of other toxic contaminants: heavy metals, radionucleoids and other toxic elements,” Parratt said.

The Resources Council disagrees saying salinity is the major concern.

Both AgForce and the Queensland Conservation Council agree that mining companies should be treating the legacy water before it is released into waterways.

“Given the amount of other contaminants that are likely to be in that water, we really don’t see that it’s necessary to risk the potential environmental impacts, nor risk town water supplies, when coal mines can well and truly afford to treat that water using reverse osmosis technology,” Parratt said.

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