Integrated risk management in mine closure: the C_RI model as a strategic planning tool

The decommissioning of mining operations presents multidimensional complexities and potential environmental, socioeconomic, and reputational liabilities. Conventional risk assessment methodologies in this context often lack integrated approaches and adequate parameterization for comparability between different scenarios. This article proposes the development and application of the Closure Risk Index (C_RI), an innovative methodology that integrates concepts adapted from Failure Mode and Effects Analysis (FMEA), Probable Maximum Precipitation (PMP), and Human Development Index (HDI). The methodological systematization included: identification of potential failure modes; parameterized risk characterization; adaptation of PMP principles to estimate maximum potential impacts; incorporation of HDI concepts for normalization of risk indicators; and matrix integration for calculating the C_RI as a weighted average of normalized indicators. The application of the model in a case study at the Córrego do Meio Mining Group demonstrated its effectiveness in hierarchizing risks and comparing alternative scenarios, revealing that critical risks were associated with water contamination and social-community impacts. Analysis of risk matrices demonstrated the general reduction of risk levels after implementing control measures. The C_RI model proved to be a robust and transparent tool for strategic planning of mine closure, allowing prioritization of mitigating measures and optimization of resource allocation. Its applicability transcends the case study, constituting a significant methodological contribution to sustainability in the mineral sector.

Keywords:
mine closure; integrated risk management; closure risk index (C_RI); mining decommissioning; mining sustainability.