DAR as a Pillar of GISTM Governance: Evaluation of the Cumulative Impact of Deviations in Proactive Tailings Risk Management. Case Study.
Authors: Adolfo López1, Carlos Faundes1, Thiare Magallanes1, Juan Carlos Paredes1
Conference: 2nd International Symposium on Tailings Deposits
Date: March 11-13, 2026
1 Knight Piésold S.A., Santiago, Chile
ABSTRACT
The Global Industry Standard on Tailings Management (GISTM) requires a formal Management of Change system by incorporating the Deviation Accountability Report (DAR) (Requirement 6.5). This paper presents an approach for developing a DAR based on two tailings storage facilities within the same mining group, operating under differing contexts that influence their respective risk profiles.The DAR consolidates and evaluates the cumulative impact of design and operational deviations on the facility risk level. Deviations arising during construction and operation-such as embankment raises, geomembrane damage, and temporary reductions in freeboard-are analyzed. These deviations are linked to Potential Failure Modes (PFMs) and their cumulative effect on both the probability and consequences of failure, as reflected in the project risk matrix and risk profile. The primary value of the DAR lies in strengthening governance, by requiring technical evaluation and hierarchical approval of deviations, and by facilitating updates to critical documents such as the Design Basis Report and the Operation, Maintenance, and Surveillance Manual. Formalizing the process through DAR records and a change log ensures proactive tracking aligned with actual facility conditions. The case studies demonstrate that, beyond regulatory compliance, the DAR is a key tool for adaptive risk management and accountability in tailings storage facilities.
Download the full paper.