Engineering geomorphology to inform rehabilitation design: a Yallourn case study

Authors: Chan, I; Sullivan, T; Nash, T; Tatnell, L Download Paper Open access courtesy of:

DOI https://doi.org/10.36487/ACG_repo/2615_48

Cite As:
Chan, I, Sullivan, T, Nash, T & Tatnell, L 2026, 'Engineering geomorphology to inform rehabilitation design: a Yallourn case study', in AB Fourie, G Boggs, J Heyes & M Tibbett (eds), Mine Closure 2026: Proceedings of the 19th International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 1-15, https://doi.org/10.36487/ACG_repo/2615_48



Abstract:
Understanding how landforms evolve and perform is key to predicting long-term behaviour. Engineering geomorphology applies this knowledge to both natural and human-modified terrain, and inspection of such landforms and how they perform can inform design decisions for safe, stable and sustainable mine rehabilitation. Conventional closure design often overlooks long-term performance, relying on assumptions or limited data. This paper demonstrates a performance-based geomorphic approach to guide slope design and closure planning. A case study from the Yallourn mine in the Latrobe Valley examines 110 natural slopes and 16 cut slopes in the Haunted Hills Formation (HHF). Natural slopes were assessed by height and angle across multiple land facets, while cut slopes were evaluated for geometry and performance indicators such as erosion and instability. Results indicate that cut slopes up to 25° generally perform well long-term, while more mature flatter landforms up to 15° (4H:1V) are common. These findings were used to establish the basis of rehabilitation slope angles for the HHF at Yallourn, with refinement for site-specific conditions where present. The case study demonstrates that engineering geomorphology enables evidence-based, site-specific design, reducing reliance on conservative assumptions and improving confidence in long-term landform performance.

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