Mining's Dirty Secret
In late January ex-cyclone Oswald forced around 20 mines across Queensland to dump waste water into passing floods. Many reasoned that the high volume of water passing through river systems would dilute any contaminants to safe levels.
But for one community west of Rockhampton, a spill of toxic water from an old gold mine has turned out to be worse than first thought.
The abandoned Mount Morgan gold mine, which overflowed for the first time in its history three weeks ago, is still spilling acid and heavy metals into the Dee River. Local farmers now say that the Dee River is an unnatural shade of blue-green for a lot of its length, and birds and fish are dying.
Neal Johansen, who lives near Mount Morgan, says that although waste water has been trickling out of the old mine for years, the damage caused by Oswald dumping 700 mm of rain in the area has been catastrophic. He’s been surveying the river to assess the damage.
‘I've never before seen the white sediment on the bottom, which is probably aluminium hydroxide that's now dropped out because it's increased to a pH level where it will actually fall out of suspension,’ Mr Johansen says. ‘I certainly have never seen this before. So that is actually of quite a huge concern I should imagine... 55 km downstream [from the mine].’
A little further downstream from where Mr Johansen has found evidence of low pH levels, farmer Ian Scott has now found dead birds.
‘We saw quite a few dead animals—birds, there’s odd fish, cockatoos, there’s even crows, magpies, peewees,’ Mr Scott says. ‘I’ve probably seen about 20. We saw a shag or waterbird floating past. It was sick—obviously been poisoned.’
The Dee River is at the top of the giant Fitzroy River catchment; it’s 400 km by river downstream to the city of Rockhampton. Other mines in the catchment have been discharging water into the floods, and the government and water authorities say that by the time it reaches Rockhampton it’s so diluted that no pollution would be detectable, although water and sediments are being tested.
But the devastating impact of the Mount Morgan overflow tells a different story. The Queensland government manages Mount Morgan as an abandoned mine and has been trying for years to get the water level in the pit down. There’s a water treatment works on site, and four big evaporators. There are now plans to divert fresh water runoff away from the pit.
The farmers downstream say that’s not enough. They want the Queensland government to finish its rehabilitation plan for the mine—to treat all the water, drain the pit, fill it in and cap it.
Passing the buck
But fixing Mount Morgan would cost hundreds of millions of dollars, and it’s something successive Queensland governments have shied away from.
Queensland’s Assistant Mines Minister, Lisa France, says it all boils down to money.
‘It's very easy to have textbook answers of how we could fix problems but in reality we need that money,’ she says. ‘And when it comes down to a limited revenue for a government—and a government who has said definitely we won't be putting taxes up—we do need to be very cautious with that money that we do have, and spend it wisely. I obviously would like to have an awful lot of money put into the abandoned mines program. However, other people might want to see hospitals and roads and education.’
A national problem
The types of issues associated with Mount Morgan and its legacy waste water are not confined to residents of the Dee River. The recent floods have exposed problems in many of the 15000 abandoned mines in Queensland, and the 50000 abandoned mines across the country. Rehabilitating them is left to the states, and there is no clear standard about how best to do it.
At the University of Queensland’s Centre for Mined Land Rehabilitation, Corinne Unger, an expert in abandoned mines, says the problem has largely escaped scrutiny because it’s out of sight.
‘That is the history of abandoned mines,’ she says. ‘They’re scattered across the state. They’re largely in regional Queensland, and across the rest of Australia they're largely in regional areas. They're not where most of the voters are. But are we living in a developed country or a developing country? That's really what we've got a ask ourselves.’
At Mount Morgan, Mr Johansen says now that the mine pit is full it’s going to be very hard to stop it overflowing again. The problems in the Dee River can no longer be ignored.
‘[T]hough it's been swept under the table for many many years now, we’ve had 20 years that we haven't been happy with what's going on,’ Mr Johansen says. ‘Get rid of the water in the open cut pit. It could have been done many times over and it's finally come to a head now. We have heard many politicians come up and say that they were leaving and "Thank God it didn't happen on our watch!". But now it's happened on somebody's watch.’
Hear Ian Townsend's full investigation on Background Briefing, Sunday at 8am.