Barsi, D & Slingerland, N 2025, 'Complete closure landforms: geomorphic design with commingled tailings and waste rock ', in S Knutsson, AB Fourie & M Tibbett (eds), Mine Closure 2025: Proceedings of the 18th International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 1-12, https://doi.org/10.36487/ACG_repo/2515_78 (https://papers.acg.uwa.edu.au/p/2515_78_Slingerland/) Abstract: Traditional mine waste structures (waste rock dumps and tailings facilities requiring dams) have the potential to create long-term physical and chemical stability challenges and often require perpetual monitoring and maintenance. In response to this risk, commingled facilities have been proposed whereby waste rock and dewatered tailings are mixed and co-disposed of in one facility, supporting both physical and chemical stability. Additionally, an often-unrealised benefit of commingled materials is the ability to compact and shape them similarly to natural soils. This work investigated the closure implications of the present (traditional) mine waste management approaches used at mine sites around the world. Failures of closure landforms were investigated and categorised, contributing factors for the failure mode were identified, and potential mitigation or prevention measures identified. The assessment indicated that commingled mine waste materials in combination with a geomorphic landform approach results in substantial opportunities, including reduced long-term monitoring, reduced long-term water treatment, and reduced lifecycle costs. Keywords: commingled mine waste, geomorphic landform design, opportunity assessment