Remy, M, Clode, K, Motchan, T & Kerr, H 2024, 'Water treatment development plan for Rio Tinto closure assets', in AB Fourie, M Tibbett & G Boggs (eds), Mine Closure 2024: Proceedings of the 17th International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 1311-1320, https://doi.org/10.36487/ACG_repo/2415_95
(https://papers.acg.uwa.edu.au/p/2415_95_Clode/)
Abstract: Effective water management is paramount in mitigating the environmental and social impacts of mine closures. In response, Isle and Rio Tinto Closure (RTC) have embarked on a collaboration aimed at minimising the financial, environmental and social risks associated with mine closure, with a particular focus on water management and treatment. This effort is underscored by a commitment to best practices, adaptive operating philosophies and the integration of new technologies designed to significantly reduce treatment costs and minimise health, safety, and environmental risks without compromising on environmental performance.
The challenge lies in the unique quality of water at each site, which may vary in terms of salinity, pH level and metal content, as well as the fluctuating volumes requiring treatment. Our comprehensive assessment of water management and treatment practices across 10 RTC assets has provided a foundation for identifying operational improvements and technological innovations. These include proposals for alternative technologies at sites with existing water treatment plants to reduce operational costs, meet compliance requirements more efficiently, streamline procurement processes, and lessen environmental impacts through reduced chemical and energy usage.
For sites without established treatment facilities we recommended a range of suitable acid rock drainage prevention methods, water management strategies and water treatment processes tailored to individual site conditions. In instances of tightening discharge limits we advised on effluent polishing techniques to meet future regulations. Furthermore, alternative discharge routes were explored for one site, with corresponding treatment recommendations provided.
This paper will detail the opportunities identified as feasible through collaboration with local site teams, initiating business cases for their implementation. These findings not only highlight the potential for operational and environmental improvements but also pave the way for future innovations in mine closure strategies.

Keywords: mine closure, water treatment, compliance, innovation