Governance of Containment Structures: How International Lessons Are Redefining the Standard

The new level of requirements for dams, tailings dams and dikes

Over the past decade, the mining industry has moved beyond the logic of mere minimum technical and regulatory compliance and has begun operating under much higher expectations. The governance of tailings dams, waste rock piles, stockpiles, containment dikes, and associated structures has become a topic of discussion for boards of directors, institutional investors, and global public opinion.

Three movements explain this change. First, high-profile disasters, such as Mount Polley, Mariana, and Brumadinho, exposed systemic flaws in the way containment structures are designed, operated, and supervised, going far beyond mere “miscalculations.” Second, an explicit global pattern emerged, materialized in… Global Industry Standard on Tailings Management (GISTM), which brings together principles and requirements that integrate technical, social, environmental, and governance aspects. Third, global investors have begun to act in a coordinated manner through initiatives that demand transparency at the facility level and concrete evidence of adherence to safety and governance standards.

In this context, containment structures cease to be seen as peripheral infrastructure of the operation and begin to be treated as critical risk assets, with a direct impact on the cost of capital, ESG assessment, social license to operate, and business continuity. For operators in Brazil, the central question is no longer “Am I complying with current legislation?and it becameIs my governance over containment structures comparable to that of companies valued by the largest global investors?.

Governance of containment structures as a system

In the practice of large global mining companies and in strategic consulting reports, governance is not synonymous with organizational chart. It refers to the design of how critical decisions are made, escalated, challenged, and revised throughout the lifecycle of the structure.

When applied to containment structures, this governance is organized around five components that need to be consistent with each other.

First of all, the Architecture of responsibilities and critical rolesGISTM introduces and consolidates three central figures: 

• Accountable Executive, ultimately responsible for the structure before the board;
• Engineer of Record (EoR), responsible for the technical integrity and consistency of the design, operation and modification history;
• Engineer responsible for the installation, focusing on day-to-day integrity, data integration, and coordination of corrective actions. 

In mature organizations, these roles have clear formal mandates, direct access to decision-making forums, and mechanisms to protect against conflicts of interest.

Secondly, the decision-making and scaling modelDecisions such as raising, reinforcing, decommissioning, altering operating regimes, or accepting a certain level of geotechnical uncertainty are not treated as local engineering issues. They follow formal approval pathways, with predefined risk criteria, mandatory participation from corporate geotechnics, risk management, legal departments, and, whenever necessary, board or council review. Objective triggers, such as combinations of instrumentation readings, anomalies in inspections, and results from new modeling, determine the escalation.

Thirdly, integrated information flowsInternational experience shows that good practice requires a single database where instrumentation, inspections, interventions, numerical analyses, and operational events converge into a single repository with traceability. From this database, reports and dashboards adapted to different hierarchical levels are generated without any "parallel versions"Regarding reality, senior management has access to summaries that preserve the technical substance and allow for a clear view of residual risk."

Fourthly, the lines of defense and technical independenceModels aligned with GISTM and modern corporate risk frameworks are structured along three lines. The first corresponds to the operation and maintenance of structures. The second comprises the corporate technical function, including geotechnics, hydrology and hydraulics, hydrogeology, and risk management, which defines standards, supervises, and questions decisions. The third encompasses internal audit and independent technical review through recurring external panels.

Finally, culture and incentivesWithout a proper culture, formal design cannot be sustained. Cases of rupture reveal patterns of normalization of deviations, reluctance to deliver bad news to management, and an implicit incentive to prioritize production and short-term CAPEX at the expense of structural integrity. More mature companies are beginning to associate a significant portion of management goals with indicators of the integrity and governance of containment structures, and not just with volume and cost-per-ton targets.

What do major disasters teach us, beyond geotechnics?

Independent investigation reports and analyses of Mount Polley, Mariana, and Brumadinho converge on one troubling point: it is rarely a single miscalculation or an isolated incident in the field. The collapse is almost always the result of a chain of decisions, omissions, and incentives.

A key lesson is that technical failures almost always reflect a decision-making failure. The issue is not just insufficient data, but the fact that the associated uncertainties are not treated as a central element in the decision-making process, leading to design revisions, increased safety margins, and adjustments to the monitoring strategy.

A second lesson is that compliance does not replace governance. The problem is not the absence of rules, but failures in the integration between monitoring and project data, in the internal capacity to question risk trajectories, and in the existence of clear escalation and veto mechanisms in the face of signs of deterioration.

A third lesson concerns conflicts of interest and excessive reliance on external reports. The lesson is straightforward: responsibility for risk cannot be outsourced because it is a shared responsibility. External reports are important inputs, but they are not a substitute. accountability Internal regulations do not replace the company's obligation to understand, accept, or reject residual risk in a conscious manner.

These elements fueled the formulation of GISTM and reinforced, for investors and regulators, the perception that the way a company manages its containment structures is, in practice, a quality test of its own corporate governance.

Brazil faces a robust framework and an execution challenge.

From a regulatory standpoint, Brazil is not a scenario of regulatory vacuum. On the contrary, the country has made significant progress since the major disasters.

The National Dam Safety Policy established the principle of entrepreneur responsibility and structured duties for monitoring, reviewing, and communicating risks. ANM Resolution No. 95/2022 consolidated and updated safety standards for mining dams, defined classification criteria by Risk Category and Associated Potential Damage, reinforced the requirement for automated monitoring systems for more critical structures, and formalized the role of the Engineer of Record. States such as Minas Gerais created specific policies for emergency action plans, defined requirements for interfacing with Civil Defense, and, in some cases, restricted new dams in occupied self-rescue zones.

Despite this framework, practice still shows an asymmetry between what is in the standard and what is observed in the field. It is common to find tailings dams with relatively robust governance arrangements alongside structures with weaker controls, even though they may present significant potential damage. The Engineer of Record often accumulates high personal responsibility, but with limited decision-making power over CAPEX and operational priorities. Instrumentation and inspection data are growing in volume, but remain dispersed across different systems, without converging into an integrated risk dashboard accessible to senior management. Risk Impact Reports (RISR), Risk Prevention Programs for Dam Safety (RPSB), Dam Safety Certificates (DCE), Emergency Action Plans for Dams (PAEBM), and rupture studies are frequently treated as contractual products, and not as drivers of strategic decisions and investment prioritization.

In summary, the country has a regulatory framework that aligns with global standards, but its competitive advantage, and real risk reduction, lies in its ability to implement governance that approaches international best practices.

A four-layer reference framework for the Brazilian context.

Taking GISTM, ICMM guidelines, and public practices of large global mining companies as a reference, it is possible to structure a four-layer framework adapted to the Brazilian reality.

The first layer is the board and senior management..

This level needs to define a specific risk appetite for retaining structures, explicitly stating, for example, minimum safety margins above normative criteria, a stance towards legacy structures with obsolete designs, and criteria for accepting geotechnical and hydrological uncertainties. It is also at this level that the [missing word - likely "agreements"] are formalized. Accountable Executives For critical structures, risk or sustainability committees are structured with an explicit mandate to periodically review the portfolio of structures, monitor the implementation of recommendations from independent reviews, and evaluate major investment decisions from an integrated risk perspective. When this happens, containment structures cease to be "local engineering problems"and they come to occupy a formal place on the company's strategic risk map."

The second layer is the corporate function of containment structures..

This refers to the "technical brain"Governance. This function must bring together and articulate geotechnics, hydrology, hydraulics, hydrogeology, tailings management, corporate risk and, in many cases, sustainability and the environment. Its mandate includes establishing internal policies, minimum design and operation criteria, standards for rupture studies and PAE/PAEBM (Preventive Emergency Action Plan/Preventive Emergency Action Plan for Mining Dams), requirements for monitoring, decommissioning and closure. Independence from the operational structure and production targets is an essential element. This function also needs to be integrated into..." Enterprise Risk Management and to corporate ESG, connecting risk decisions of the structures to financial impact analysis, the perception of critical stakeholders, and the requirements of financiers and insurers.

The third layer is the site and operations level..

Here, governance translates into operational discipline and good processes. Change management must be structured so that any relevant alteration in geometry, disposal method, drainage, pumping, hydrological regime, or contractual operating arrangement is formally recorded, technically evaluated, and accompanied by an explicit impact analysis on safety factor, performance margins, and residual risk. Procedures need to provide clear triggers for restricting or halting operations, lowering water levels, executing emergency reinforcements, and immediate communication to higher decision-making levels. Inspection routines should classify anomalies by criticality and link each class to deadlines and responsible response personnel. Continuous training programs are necessary so that operation, maintenance, and contractor teams know how to interpret instrumentation, recognize early signs of instability, and execute emergency plans unambiguously.

The fourth layer is independent review and transparency..

Independent review panels, with multi-year mandates, clear scopes, and autonomy to access data, conduct field visits, and interview teams, are a central component of models that purport to align with the global standard. Internal and external audits should assess not only formal adherence to the standard but also the effectiveness of the governance model, analyzing decision flows, response times, record quality, and the rate of implementation of critical recommendations. Finally, transparency with investors, communities, and authorities, in line with global initiatives for the disclosure of data on dams and containment structures, contributes to reinforcing this. accountability and discipline.

Governance for the entire portfolio, not just for tailings dams.

A distinctive feature of more mature organizations is the expansion of the governance scope beyond conventional tailings dams. Tall waste rock piles in complex terrains, buffer piles associated with the beneficiation plant, water, sediment and mud containment dikes, remaining pit slopes and containment structures in pits are now treated as part of a single portfolio of containment structures.

This means that criticality criteria, the requirement for EoR-like roles, the application of change management processes, instrumental monitoring, and independent review no longer depend solely on traditional regulatory classification but are defined by real risk. In other words, the question ceases to be "Is this structure formally classified as a dam according to regulations?” and becomes “What is the potential harm associated with this harm, and what level of control and governance is compatible with that harm?.

An implementation agenda from the current state to the target state.

Companies seeking to approach global standards tend to organize their governance improvement journey into clearly defined phases.

The first step is a maturity diagnosis..

This step involves evaluating existing governance in relation to GISTM, ICMM guidelines, and ANM 95/2022 requirements, identifying gaps in governance architecture, processes, data, culture, and independent review, and, whenever possible, conducting benchmarking with global peers.

Next, a target model is defined.

At this stage, the company designs the desired architecture of roles, forums, and information flows, establishes criticality criteria, and segments its portfolio of containment structures into groups with distinct levels of requirements, integrating the theme into... Enterprise Risk Management and to discussions regarding mine planning and medium- and long-term CAPEX.

The third step involves redesigning critical processes..

Change management processes, disruption study and scenario planning cycles, CAPEX and OPEX prioritization, and management of recommendations from consultants and regulatory bodies should be reviewed, standardized, and integrated. In parallel, it is crucial to consolidate instrumentation, inspection, and intervention data into a single platform capable of generating appropriate dashboards for both technical teams and senior management.

From there, it is recommended to test the new model using pilot programs..

A subset of critical structures can be chosen for full application of frameworkThis allows for the identification of necessary adjustments before rolling them out to the entire portfolio. This approach reduces implementation risks, generates practical learning, and accelerates the institutionalization of new routines.

Finally, it is necessary to work on culture, training, and governance metrics..

Training programs aimed at leadership, technical areas, and operational teams help align language, criteria, and expectations. Structural integrity and governance goals need to be included in managers' performance indicators. Simple indicators, such as the proportion of critical recommendations implemented on time, the percentage of structures with up-to-date independent review, and the number of change management events completed with formal risk re-analysis, allow monitoring the evolution of governance over time.

Conclusion: Governance as a proxy for corporate maturity

The way a company governs its containment structures has become, in practice, a direct indicator of its risk management maturity. In Brazil, where recent history includes some of the world's largest geotechnical disasters, the space for superficial narratives is limited. Regulators, investors, communities, and the Public Prosecutor's Office tend to demand convergence not only to local regulations but also to demonstrable global standards.

Companies that view the governance of containment structures merely as an exercise in meeting minimum requirements will continue to operate in a high-risk zone, exposed to low-probability, high-impact events with potentially irreversible human, environmental, financial, and reputational consequences.

On the other hand, organizations that consistently internalize international lessons, structure a robust governance model, and integrate geotechnical risk into the core of corporate decision-making will have a greater capacity to reduce the probability and severity of critical events, preserve and generate value in assets currently penalized by risk perception, and strengthen their social and regulatory license to operate in the long term.

In short, governance of containment structures has ceased to be a sectoral issue and has become a consolidated test of management quality. Those who understand this clearly and act with technical depth, organizational coherence, and transparency will be better positioned in a sector where the level of demand has changed structurally and is not likely to regress.