Abstract
Tailings storage facility failures often result in release of large volumes of tailings and water, directly impacting environment and economy, and pose a high risk to the lives of workers and communities in the areas downstream of the facilities. The United Nations reported about forty such incidents in the past decade, raising the alarm of communities nearby Tailings Storage Facilities due to the potential scale of these events.
The Trigger Action Response Plan (TARP) methodology aims to identify key monitoring parameters relating to dam safety. The pre-defined trigger levels are provided for performance criteria and describe actions to be taken if these values are exceeded. Risk levels classify events where these values trigger a response to mitigate or eliminate risk.
These parameters are usually monitoring of deformations, settlements, pore pressures and phreatic levels. Specialized instrumentation, such as piezometers, inclinometers, shape arrays, and survey monuments, is used to obtain those parameters.
Based on the instrumentation available at each facility, a series of crucial cumulative information is collected, allowing improved knowledge of the monitored TSF structure. It also enhances risk-based decision-making by increasing the understanding of uncertainties and the potential for expected deviations during operations.
This document presents the recommended operating parameters based on historical data, current instrumentation readings, and model analysis of a TSF built in the ’80s, recently reinforced with a buttress and instrumented with 13 piezometers in 12 locations, and 13 survey monuments with one control point.
Finally, conclusions and lessons learned are provided, aiming to give a framework of where to take the future of instrumentation and TARP, presenting potential options such as automatization of instrument readings, generation of graphs and models in real-time, and telemetry, among others.
