Gresswell, R, Foley, G & Faithful, J 2019, 'Hydrogeological modelling to inform closure planning for Hazelwood Mine', in AB Fourie & M Tibbett (eds), Mine Closure 2019: Proceedings of the 13th International Conference on Mine Closure
, Australian Centre for Geomechanics, Perth, pp. 1353-1366, https://doi.org/10.36487/ACG_rep/1915_106_Gresswell
The Hazelwood Mine, located in the Latrobe Valley of Victoria, ceased operation in 2017 after over 50 years of mining. The closure of the mine represents an important stage in the hydrogeological evolution of the Latrobe Valley aquifer systems. It marks the transition from the operational phase of mining which involved the significant depressurisation of confined aquifers to ensure safe mining conditions, to the closure phase when the mine will be filled to form a lake with the depressurisation system progressively shutdown.
Key hydrogeological issues associated with the closure include the rate of recovery of piezometric heads in the aquifers and the interaction of groundwater with the lake. Hydrogeological modelling is a critical component of closure planning, providing inputs to other technical studies required by resource managers to inform groundwater and surface water licencing aspects of the mine closure.
This paper describes the detailed hydrogeological modelling undertaken to support closure planning for Hazelwood, including:
Keywords: groundwater, lake, modelling, closure
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