Digging deep into Yallourn mine failures

On June 6 the Morwell River collapsed into the Yallourn coal mine in the Latrobe Valley. The river, perhaps Australia's most poorly treated, has been moved six times to allow access to new coal deposits. The day after the mine site collapsed, TRUenergy dammed the river in two places, diverted the flow of the river into their mine pits, and shut down most of the power station.

If you've never seen a broken river before, here's what it looks like.

Over a month later the situation is escalating in seriousness. The mine is filling with water much sooner than anticipated (see photostream here) and the power station continues to operate at half capacity. The company is proposing to send the entire flow of the Morwell River through a pipe, perhaps indefinitely. And Victoria's EPA has issued an approval to TRUenergy for the emergency dumping of around 300 ML of contaminated water per day into the Latrobe River which flows into the Ramsar listed Gippsland Lakes. No-one was under the impression that Victoria's brown coal mines and power stations were a sustainable industry, but this is getting ridiculous.

After a month of downplaying the incident, the Baillieu government has finally agreed to an expert inquiry into exactly what went wrong at Yallourn and the flow-on consequences. This inquiry is critical as the Baillieu government makes key decisions about the future of coal mining in this state, with a proposal to turn Victoria into the next Pilbara on the table. TRUenergy has also repeatedly downplayed the incident and promised that things would be up and running again shortly, only to miss their own deadlines.

Perhaps China Light and Power's sharemarket statement last week that the Yallourn mine incident will affect earnings and profits will lead to a more sober assessment of the damage. TRUenergy is taking a double hit from lost power station revenue and the remediation and earthworks bill will run into hundreds of millions of dollars. While much of this cost will be covered by insurance, expect insurance premiums for all Latrobe Valley miners to rise sharply in response to this incident.

With all of this in mind, here are six lessons that the Victorian community can draw from the failures at Yallourn, and use them to judge future coal mine proposals in the state.

1. Moving rivers is not a good idea: Self evident to some perhaps, but by no means an accepted fact in engineering circles. In fact TRUenergy has plans for future diversions of the Morwell River, and if the Baillieu government and federal energy minister Martin Ferguson's plans to turn the Latrobe Valley into the Pilbara are realised, more rivers will be interfered with. The Morwell River diversion was justified by sophisticated modelling exercises that predicted that the diversion would cope with all but a 1 in 10,000 year flood event. While flooding in Gippsland in June was serious, the region floods regularly and it certainly wasn't a 1 in 10,000 year flood event.

2. Latrobe Valley mines are repeat offenders: This is not an isolated incident. In 2007 the Yallourn mine wall collapsed into the Latrobe River. A detailed Mining Warden Inquiry into the incident essentially found that Yallourn's operating practices had deteriorated over time and that the mine walls they were cutting were too steep. Subsidence at the Hazelwood mine in 2011 lead to the closure of the Princes Freeway for months. The latest incident at Yallourn is the third serious incident in five years.

3. The Victorian government is not managing the impacts of existing mines: Repeated failures at Latrobe Valley mines raise questions about the adequacy of the Victorian government's regulation of mining activities. DPI primarily operates as a resource development arm of government, and its regulator activities come a distant second. A brief search of the DPI website finds multiple pages devoted to providing information to potential investors or developers of Victorian brown coal. By contrast there is no mention of the current problems at Yallourn or what is being done to manage the disaster.

This is highly concerning. Returning to the 2007 mine collapse at Yallourn, the Mining Warden report made a startling conclusion, noting:

“The open cut mines in the Latrobe Valley are very large excavations. The mines are not rigid structures, they are highly deformable and the deformations spread a long way outside the mine perimeters…They are in part surrounded by natural and man-made infrastructure. This infrastructure is often quite rigid or inflexible. In an engineering sense deformable structures next to inflexible infrastructure can result in some incompatibility, which in a wider context means risk.”

This environment of risk, coupled with a regulator who gives every appearance of being asleep at the wheel, is a dangerous and potent combination.

4. Pursuing new mines is therefore a bad idea: The Victorian government is proposing to allocate 13 billion tonnes of Latrobe Valley coal in 2012/13 in the hope of establishing an export coal industry. That's equivalent to 13 mines the size of the Hazelwood pit. We currently have just three mines in the Latrobe Valley, and persistent and serious problems are emerging. From an emissions perspective developing new brown coal mines and export industries is ridiculous. From a local environmental perspective in the Latrobe Valley the cumulative impacts of mines on rivers and groundwater, agricultural land and community health is reckless.

5. Far from needing less environmental regulation we need more: Big industry and Conservative forces Australia-wide are waging an attack on environmental laws and protections branding them as ‘green tape'. In Victoria, the Baillieu government held an inquiry looking at ways to fast-track mining approvals processes. Many regulatory processes have been outsourced to the miners themselves. For instance, the EPA is not undertaking water quality monitoring of the contaminated water TRUenergy is dumping into the Latrobe River. Rather they are relying on company-provided data. The current shemozzle at Yallourn highlights exactly why independent and rigorous environmental regulation is important.

6. We've had a sneak preview of what the world looks like without one of our big generators, and the lights are still on: If there's one upside to the Yallourn disaster its that its shown that we can live without one of our largest and most polluting power stations. Yallourn and Hazelwood are both currently in negotiations (along with three other small power stations) for contracts for closure with the federal government. The Victorian government has criticised contracts for closure and questioned whether we'll be able to keep the lights on. While we haven't experienced summer's peak power demands yet, if we can maintain energy security when losing nearly all of a 1450 MW generator overnight, we should have no problems dealing with the staged closure of 2000 MW of brown coal over the next eight years.

If lessons are to be learnt from this disaster, it's that Victoria's regulatory environment and mine operators cannot be relied upon to cope with the proposed massive expansion of brown coal mining across the state, let alone the serious threat to the health of our environment and communities that it would create. The Baillieu government is not doing Victorians any favours by increasing our reliance on highly polluting and damaging coal.

Mark Wakeham is Campaigns Director at Environment Victoria.