Regulatory delays may be contributing to critical problems at a lead-zinc mine in the Northern Territory, according to experts. 

Glencore's McArthur River Mine’s waste rock dump started spontaneously combusting in 2013, creating a  plume of sulphur dioxide smoke, followed by news of acid seeping through the mine site near Borroloola on the Gulf of Carpentaria. 

The Northern Territory Government has been struggling to deal with the major environmental issues, often through its Independent Monitor office. 

Researchers from UNSW's Global Water Institute have gone back over 12 years of reporting by a string of consultants that have been appointed as Independent Monitors.

“The lack of timely action on urgent issues raised by the Independent Monitor has resulted in long-term and unacceptable impacts to the community and environment,” says a new report; Monitoring The Monitor. The report is available in PDF form, here.

“It is apparent that inefficiencies and flaws in the regulatory process decrease the effectiveness of the Independent Monitor audits as a tool to facilitate better environmental management.”

The report pointed out that the Independent Monitor told the Government about pyretic rocks that were reacting on the mine site as early as 2008.

While the Independent Monitor reported spontaneously combustion of the waste rock dump in March 2013, the Northern Territory Government approved an expansion plan to double the mine size just a few weeks later. 

“It took 12 years from when the Independent Monitor first reported the problems with the reactive waste rock for the environmental process to really catch up with that,” UNSW researcher Professor Fiona Johnston has told the ABC.

“And that means that this non-benign rock, this potentially acid forming rock, was out and exposed to the environment in ways that shouldn't have happened.”

The report also revealed government delays in responding to the Independent Monitor's recommendations, including on the issues of seepage from the tailings dam into creeks, and threats to the water level in sacred waterhole, Jirinmini.

The report says 117 recommendations of the Independent Monitor had not been carried out at the time of the most recent government report, which was over two years ago.

Professor Johnston said the Independent Monitor should have its powers strengthened.

“The Independent Monitor could be a great system but it needs more resources and more teeth,” she said.

“We would like to see a much better link between the regulator and the recommendations from the independent monitor, to enforce what it recommends.”
The Northern Territory Government has since reaffirmed Glencore's permission to continue expanding the mine.

The Territory says it is confident that the company is helping avoid fires at the waste dump by improving the cover of the pyretic rock.

The Government also supports the company's plan to cover completed parts of the waste dump, which is set to hold about half a billion tonnes of waste rock, with a bitumen covering.

Glencore claims that “spontaneous combustion on our waste rock pile has been controlled since 2015 and remains under control now”.

“McArthur River Mine is committed to operating a safe, responsible and environmentally sustainable mining operation,” the company said.

“The McArthur River is healthy, water quality is good and fish are safe to eat.”