Yallourn stuck on quarter capacity as scramble continues to save coal mine

EnergyAustralia’s Yallourn coal-fired power station continues to operate at a quarter capacity, with no clear decision yet on how to fend off the threat of flooding at the neighbouring brown coal mine that feeds the plant.

The company said it was extracting just enough coal from the mine to keep one of the power station’s four units ticking over, as it finalised plans with the Victorian government to divert the Morwell River.

The 1,480 megawatt power plant supplies about 20 per cent of Victoria’s electricity. That means, with three quarters of the units out of action, the state has temporarily lost 15 per cent of its generation capacity.

Extreme rainfall almost two weeks ago caused the Morwell River, which runs through the Yallourn mine, to swell to nearly 40 times its usual flow, putting strain on the man-made embankment that prevents the water from spilling into the mine.

As the water receded, it revealed cracks in the wall, raising the real risk that the mine would flood for the second time in less than a decade.

EnergyAustralia said in a statement on Tuesday it hoped to seal the visible cracks by the end of the week, weather permitting. However, a full assessment of the damage would likely require the river to be diverted entirely – a plan that EnergyAustralia is discussing with the Victorian government.

“Our focus remains on the immediate work in front of us,” energy executive Liz Westcott said. “That is, the continued safety of our people, undertaking temporary measures to seal the cracking, assessing options to divert the water away from the mine, and increasing mining activity where it’s safe to do so.

“Meanwhile, our work continues with the Victorian government to finalise a proposal that will help manage water flows to relieve pressure around the impacted area and enable longer-term repairs. We are working through the finer technical details together,” she said.

A spokesperson for the Victorian Energy Minister Lily D’Ambrosio confirmed no final decision had been reached.

Last week the risk of flooding prompted D’Ambrosio to declare an “energy emergency” to allow the river to be diverted without going through the usual environmental processes.

Environmental groups believe there are three options: Divert the river into the disused western pit of the Yallourn mine; divert it into the disused Hazelwood pit some kilometres upstream; or divert it directly into the the Latrobe River. Each solution has environmental problems, they say.

Meanwhile, Westcott said mining was continuing and the company was able to “secure modest amounts of coal by selectively mining parts of our fields where it was safe to do so and within areas away from the area of concern.

“This has meant we’ve been able to maintain minimum generation on one unit and meet the evening energy peak,” she said.

“This will continue, and the community can be reassured that we are in constant contact with government, regulators and unions from a safety and environmental perspective, and work is always conducted according to strict requirements.

“Separately, we continue to update the Australian Energy Market Operator (AEMO) and we understand that they have reassured Victorians that there is enough power supply to meet demand.”