Jones, B, Sullivan, T, Chan, I & Tatnell, L 2026, 'A first-principles approach to mine closure and risk in a complex system: Yallourn Mine', 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. 1-18, https://doi.org/10.36487/ACG_repo/2615_121
(https://papers.acg.uwa.edu.au/p/2615_121_Jones/)
Abstract: In mines with complex systems, it is difficult to capture key technical elements for successful closure planning and design using conventional geotechnical approaches. These conventional approaches typically rely on prescriptive processes, heuristics and reasoning by analogy derived from sites where the conditions that govern stability are often more predictable. This paper presents a first-principles approach to mine closure, demonstrated through a case study at Yallourn Mine in the Latrobe Valley, Australia. The Yallourn Mine constitutes a complex system with many mutually interacting components where stability is fundamentally sensitive to water loading. Substantial topographic relief surrounds the site, with large areas well above freespilling lake level, presenting a potential destabilising water load risk to mine batters. Successful rehabilitation involves the effective capture and controlled discharge of peripheral catchment water into the void, achieved through a pit lake and peripheral catchment drain system.
A first-principles approach derives the design solution from the basic facts of the system rather than from convention or analogy. Nonetheless, a logical risk-based framework is followed: a 2-tier risk evaluation, combining domain-specific technical risk ratings with a conventional consequence assessment to produce design criteria for each domain. Those criteria directly inform the peripheral drainage design, through targeted block sliding stability analyses along peripheral catchment alignments, from which drain requirement, extent and sizing are systematically derived. The process links the probability of hydrologic exceedance, geotechnical stability and consequence class into a coherent design framework. The integrated assessment produces practical drainage outcomes based on analytical results and validated by decades of empirical monitoring data.