Risk-informed instrumentation of tailings storage facilities

Surveillance through instrumentation and monitoring is crucial for evaluating performance and ensuring the safety of tailings dams. This importance has been well recognised by technical groups and peak industry bodies, which have released numerous publications emphasising the necessity and benefits of, and the developing techniques for, tailings dams monitoring. The attention to instrumentation has further intensified with the introduction of technologies such as InSAR, marketed specifically for the tailings industry, and the monitoring requirements outlined by the Global Industry Standard on Tailings Management (GISTM). However, the collapse of the Brumadinho dam, equipped with over 100 piezometers and several inclinometers, demonstrated that an extensive surveillance program with large quantities of instruments alone cannot prevent dam failures. Moreover, there is no one-size-fits-all solution for surveillance programs. A standardised approach to instrumentation and monitoring is neither feasible nor beneficial as each facility has unique characteristics and risks. For safety monitoring to be truly effective it must be tailored to the specific failure modes and risk controls of the facility, ensuring that deviations from expected performance are detected early enough to provide actionable warnings. This paper presents a robust, risk-informed framework for developing effective safety surveillance programs that allow tailings storage facilities owners to detect the deteriorating performance of tailings facilities and potential failure conditions, and which align with the tailings dam management framework adopted for the forthcoming revision of the Australian National Committee on Large Dams Guidelines on Tailings Dams.