Engineers Australia

Why is rehabilitating the Latrobe valley brown coal mines so hard?

Emeritus Professor Rae Mackay

As thermal power generation comes to an end in the Latrobe valley, the rehabilitation and closure of the three lignite mines has become a ‘burning’ issue. Hazelwood mine is closed, while Yallourn is now slated for closure in 2028. Loy Yang has plans to continue through to 2048, though the speed of change of the power industry may also bring forward this timetable. Lignite mining is relatively easy if you look after groundwater pressures and keep a watchful eye on fire hazards, but the ease of mining has created a headache for rehabilitation and closure. Of course, I oversimplify! The three very large mine voids need constant management and monitoring to ensure stability is maintained. Their proximity to significant infrastructure means that they can’t be allowed to fail. Finding a solution for rehabilitation that will minimise ongoing management is being made tricky by climate change pressures on water management. Climate change is also playing a role in increasing instability risks.

This talk will explore the geotechnical issues for rehabilitation of the Latrobe Valley mines and the role that has been given to the newly created Mine Land Rehabilitation Authority in support of the planning for mine closure and the relinquishment of the mining leases.

About the speaker

Emeritus Professor Rae MackayChair, Mine Land Rehabilitation Authority Board

Rae held the role of Latrobe Valley Mine Rehabilitation Commissioner from June 2017 to June 2020 before becoming the Chair of the Mine Land Rehabilitation Authority Board. He has extensive mine rehabilitation related expertise, with more than 40 years’ experience as a practising engineer, hydrogeologist and academic. He was the Director of the Geotechnical and Hydrogeological Engineering Research Group (GHERG) at Federation University, working on issues of geotechnical stability and risk at the Latrobe Valley brown coal mines from 2011 to 2017. During this time, he was also a member of Victoria’s Technical Review Board, which had oversight of stability issues across the state’s mines and quarries. He was Head of Hydrogeology at Birmingham University, UK for 15 years before moving to Australia in 2011. He has worked on and researched a wide range of geotechnical, hydrogeological and water resources problems from deep geological disposal of nuclear waste to arid zone groundwater resource and agricultural development, spanning many countries around the world.

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