Isotope techniques for sustainable water resources management in mining-related settings: A state-of-the-art review

Mining activities can significantly alter surface and groundwater systems. Therefore, sustainable water resources management has become a central requirement and strategic necessity for responsible mining. This requires tools capable of characterizing water sources, flow paths, and contaminant dynamics to support informed and responsible decision-making. Stable and radioactive isotopes are powerful tracers of the origin, age, movement, and transport of water and its constituents, as well as indicators of the water-rock interactions affecting groundwater and surface water quality. This paper reviews publications from 2022 to 2024 that discuss advancements in isotopic techniques and their applications, with the goal to promote the adoption of integrated isotopic and geochemical methods in mining-related assessments. The review is organized into three sections: 1) the understanding of hydro(geo)logical circuits: water sources and circulation, mixing processes, hydro(geo)logical alteration, river-groundwater interactions and groundwater age; 2) the assessment of mining-related contamination processes: contamination by S or by N compounds, discrimination between mining and other contamination sources, the use of minor and trace element isotopes, the salinity issues, and the identification of gas production and exchange; and 3) the application of isotope approaches for monitoring the impact of mining and assessing remediation measures, whether natural or engineered. Finally, the intrinsic strengths and weaknesses, as well as the external opportunities and limitations to the application of isotopic approaches are discussed. The review summarizes the commonly encountered sources and processes in mining settings and provides graphical outputs to assist with interpreting new experimental data, highlighting environmental isotopes as “sustainable investigation tools”. • Isotopic approaches in mining-related settings are assessed with a SWOT analysis • Graphical outputs to assist with interpreting new experimental data are provided • Environmental isotopes represent fully-fledged “sustainable investigation tools”