Heyes, J, Arvidson, H, Nirmalrajan, N & Mueller, S 2025, 'Inclusion of mineral waste in mineral resource and ore reserve reporting processes as a catalyst for responsible mine closure', 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. 1-15, https://doi.org/10.36487/ACG_repo/2515_26 (https://papers.acg.uwa.edu.au/p/2515_26_Heyes/) Abstract: Mineral Waste[footnoteRef:3] (MW), for which estimates of quantity and quality are not required to be explicitly revealed like Mineral Resource and Ore Reserve (MROR) estimates in current minerals reporting, is emerging as a critical factor in sustainable mining and is therefore a material matter for reporting. Traditionally considered as burden, or a low-priority byproduct, MW volumes in open pit mines often far exceed those of ore[footnoteRef:4] and can lead to significant environmental, social and financial consequences. Despite existing reporting codes such as the JORC Code (JORC 2012), the integration of MW into MROR reporting remains inconsistent and when done at all, is largely retrospective. This paper argues for a paradigm shift toward predictive MW reporting as a standard inclusion in MROR reports, enabling mining companies to proactively manage risks, optimise resource development and utilisation, and enhance transparency for stakeholders. [3: A definition of MW is explored as the antithesis of mineral resource in the JORC Code (JORC 2012).] [4: In this paper, the term ‘ore’ is intended to include all saleable commodities including coal, diamonds, industrial minerals etc.] Key considerations include definitions and terminology, modifying factors such as geochemical characteristics, metallurgical recovery, market conditions, and environmental risks such as acid and metalliferous drainage (AMD). Additionally, robust mine reconciliation processes for both ore and MW are essential to align predictions with operational realities, ensuring that MW is accounted for and managed effectively. Data governance and technology-driven reconciliation play a pivotal role in ensuring reliable, auditable, and transparent MW disclosures. By integrating MW into MROR reporting, the mining industry can shift from reactive compliance to transparency, social understanding and acceptance, proactive sustainability, reducing closure liabilities and unlocking latent value in previously disregarded materials. This paper explores the opportunities, challenges, and justifications for making forward-looking MW reporting a key pillar of responsible mine closure. Keywords: mineral waste, mineral resource and ore reserve reporting, mine closure, sustainable mining, competence