Wooders, H, de Hennin, S & Bumtseren, S 2024, 'Critical Path analysis and management techniques in development scheduling at Oyu Tolgoi ', in Daniel Johansson & Håkan Schunnesson (eds), MassMin 2024: Proceedings of the International Conference & Exhibition on Mass Mining, Luleå University of Technology, Luleå, pp. 141-152.
(https://papers.acg.uwa.edu.au/p/2435_A-13/)
Abstract: Oyu Tolgoi is a block caving mine located in the South Gobi province of Mongolia. In July 2022, underground production commenced and as of December 2022, approximately 101 km of lateral development had been completed with a further 118 km required to support the greater Hugo North Lift 1 orebody. Given the complex, relatively non-linear nature of the Oyu Tolgoi underground development schedule, and with the strategic focus moving to planning future blocks, a deeper understanding of the critical path was required to ensure milestone drivers were well understood and managed. Drawing upon the well-published Critical Path Method (CPM) technique, a tool was developed to not only identify critical path activities but to also quantify the nearness of activities to critical path. Nearness to critical path could then be visually portrayed as a heat map or charted as a time series to aid in the mine planning process.  

This paper is intended to share critical path management learnings and insights gathered at Oyu Tolgoi as development scheduling practices continue to evolve. Critical path identification and management is now embedded in Oyu Tolgoi planning practices, resulting in simplified communication of schedule priorities to stakeholders, increased awareness of milestone drivers and quantification of schedule risk.