An engineered mining pile with drainage and geotechnical monitoring infrastructure in Brazil.
Brazil is moving toward a dedicated national framework for the safety management of mining piles, adding another layer of scrutiny for operators already managing complex tailings, permitting and closure obligations.
The National Mining Agency, or ANM, opened Public Hearing No. 2/2026 on a draft resolution covering safety criteria for mining piles, including waste-rock dumps and dry-stacked tailings facilities. Written contributions are open from Aug. 31 through Oct. 14, while the virtual public session is scheduled for Sept. 11 at 9:30 a.m. Brasília time.
The proposal is not yet a binding regulation. Until ANM publishes a final resolution, operators remain subject to existing requirements, including NRM-19, Brazil’s mining regulatory standard for waste dumps and tailings piles. But the consultation signals that regulators are preparing to formalize more detailed, risk-based expectations for engineering, monitoring, emergency planning and mine closure.
For companies assessing mining ESG compliance in 2026, the practical question is no longer only whether a pile has a permit. It is whether the operator can demonstrate, through an auditable record, that the structure remains safe throughout its operating and post-closure life.
Brazil’s proposed mining-pile regulation
The draft resolution under discussion is part of ANM’s regulatory agenda and aims to establish safety criteria specifically for mining piles. That distinction matters because a pile is not automatically treated as a conventional tailings dam under Brazilian law.
Mining piles can include:
- Waste-rock dumps;
- Ore stockpiles;
- Dry-stacked tailings;
- Other stacked mining residues and materials.
These structures have different failure modes from impounded tailings dams. Slope instability, erosion, seepage, foundation weakness, settlement and drainage failure may be more relevant than the liquefaction and overtopping risks commonly associated with water-retaining dams.
ANM’s official hearing page provides the draft resolution, its regulatory impact analysis and the link for written contributions through the Brasil Participativo platform.
The draft will be assessed against a regulatory baseline that already requires substantial documentation. As summarized by Ignea, NRM-19 requires prior geotechnical, hydrological and hydrogeological studies, qualified technical responsibility, monitoring and control systems, drainage measures, contingency planning and restrictions on locating structures in hazardous areas.
The likely change is not a shift from regulation to regulation. It is a move toward clearer classification, more consistent reporting and stronger evidence that controls are working.
The rulebook is becoming more complex
Mining companies must distinguish between three related but separate compliance tracks.
First, NRM-19 remains the principal reference for waste dumps and tailings piles until ANM publishes new criteria.
Second, tailings dams are governed by the National Dam Safety Policy and ANM rules that have developed significantly since the Mariana and Brumadinho disasters. ANM Resolution No. 220/2025 consolidates and updates the safety framework for mining dams, with provisions taking effect in stages.
Third, occupational safety requirements can affect the use of land around mining structures. Updated NR-22 rules introduced restrictions on facilities located within a tailings structure’s safety perimeter, according to Ignea’s analysis of the 2026 requirements.
This overlap creates a compliance challenge. A facility may satisfy one technical standard but still face questions under another regime involving worker exposure, environmental licensing, emergency response or closure.
Brazil mining-pile compliance tracker
| Area | Current position | What operators should document |
|---|---|---|
| Mining piles | NRM-19 remains in force while ANM develops new criteria | Approved design basis, geotechnical studies, qualified technical responsibility and change history |
| Public participation | Written comments open through Oct. 14; virtual hearing scheduled for Sept. 11 | Internal review of the draft, submitted comments, technical assumptions and management responses |
| Tailings dams | Governed under a separate dam-safety framework, including Resolution 220/2025 | Risk classification, inspections, independent reviews, emergency plans and transition deadlines |
| Monitoring | Seepage, displacement, stability and drainage controls are central to NRM-19 | Calibration records, raw data, alert thresholds, maintenance logs and escalation actions |
| Closure | Closure planning must account for long-term stability and environmental rehabilitation | Closure design, funding assumptions, post-closure monitoring and trigger-action plans |
| Permitting | Licenses remain exposed to agency review, litigation and community challenges | Permit conditions, correspondence, technical opinions, consultation records and evidence of compliance |
Permitting disputes are raising the cost of weak records
Recent disputes show that a permit is not a permanent shield against operational or legal challenge.
In January, Reuters reported that Brazilian authorities shut down waste piles at Sigma Lithium over safety concerns. The company later cited an official ANM technical statement declaring the safety of its waste piles, illustrating how quickly the distinction between a regulatory allegation and a technical finding can become central to public reporting, investor analysis and litigation.
The episode also demonstrates why operators need a complete evidence trail. A company should be able to show what regulators inspected, which design assumptions were tested, what monitoring data was reviewed and how any corrective actions were closed.
Other cases illustrate the wider permitting risk. Federal prosecutors challenged the reinstatement of an installation license for Belo Sun’s Volta Grande gold project in Pará, according to BNamericas. The dispute includes concerns about the project’s tailings dam, potential chemical risks and effects on Indigenous communities.
In Minas Gerais, the reopening and transfer of a license connected to the Jangada mine and the former Córrego do Feijão operation has also attracted scrutiny. These disputes are not identical, but they point to a common trend: permitting decisions are increasingly assessed against historical failures, cumulative impacts and the credibility of the operator’s controls.
At the same time, broader environmental licensing reforms have created uncertainty over the division of authority between federal, state and municipal agencies. That uncertainty increases the value of conservative engineering assumptions and precise records. If jurisdiction or permit conditions are later challenged, the operator’s documentation may become the first line of defense.
What operators should document now
1. Engineering basis and design changes
The core file should explain how the pile was designed, built and modified. It should include:
- Site investigation results;
- Foundation conditions;
- Slope geometry and factors of safety;
- Material characterization;
- Water balance and drainage design;
- Construction quality records;
- As-built surveys;
- Design changes and technical approvals.
The record should also identify who accepted technical responsibility for each stage. A current design that cannot be reconciled with construction records creates avoidable ESG and legal exposure.
2. Monitoring data and decisions
Monitoring should not be treated as a collection of isolated readings. Operators should preserve the full chain from measurement to decision.
That means maintaining records for piezometers, inclinometers, survey prisms, settlement markers, rainfall stations, seepage points and visual inspections. Data should include calibration, maintenance, outages, quality checks and alert thresholds.
More importantly, the file should show what happened after an alert. A reading that crossed a threshold, triggered a site inspection and resulted in a documented engineering decision is more defensible than a dashboard full of unexplained historical data.
Geotechnical instruments provide the evidence trail behind slope and seepage decisions.
3. Governance and independent review
The company should define who can stop work, restrict access, increase inspection frequency or notify regulators. Responsibility should not be left to informal site practice.
Board and executive reporting should distinguish between:
- Routine performance;
- Emerging conditions;
- Confirmed nonconformities;
- Unresolved technical uncertainties;
- Actions requiring capital or operational change.
Independent technical reviews should be preserved with the underlying data and management responses. If the company disagrees with a recommendation, that disagreement should be documented rather than removed from the record.
4. Closure and post-closure planning
Closure cannot be a final-stage environmental document. It should be integrated into design and operating decisions from the beginning.
Operators should document the intended final landform, drainage performance, erosion controls, revegetation approach, water-quality objectives and post-closure monitoring period. Plans should also identify trigger levels and actions if seepage, settlement or erosion exceeds expectations.
For dry-stacked tailings, closure planning should address long-term cover performance, wind and water erosion, slope stability and the consequences of climate variability. For waste-rock dumps, it should address acid-generating material, drainage chemistry and physical regrading.
Closure planning must connect final landform, drainage, rehabilitation and long-term monitoring.
Mining ESG compliance 2026: base, bull and bear scenarios
The following framework is designed to help operators and investors assess regulatory direction. It is a policy scenario analysis, not an investment recommendation.
| Scenario | Regulatory outcome | Operational effect | Main risk |
|---|---|---|---|
| Base case | ANM finalizes a dedicated pile-safety resolution after reviewing public comments, with phased implementation and continued reliance on NRM-19 during the transition | Companies must inventory piles, close documentation gaps and align monitoring with risk classification | Overlapping requirements and uneven interpretation across licensing authorities |
| Bull case | The final rule provides clear definitions, proportional requirements, transition periods and consistent reporting standards | Better comparability, more predictable permitting and stronger confidence in engineered dry-stacking projects | Compliance costs rise initially, especially for older facilities with incomplete records |
| Bear case | The rule is delayed or produces broad obligations while permitting disputes and court challenges continue | Projects face redesigns, operating restrictions, additional studies or license challenges | Regulatory fragmentation, community opposition and weak historical documentation amplify delays |
The base case is the most useful planning assumption. Operators should prepare for a final rule that does not erase existing obligations and may require additional evidence rather than simply new equipment.
The compliance priority is evidence
Brazil’s proposed mining-pile regulation arrives as the sector faces pressure to expand critical-minerals production while demonstrating stronger environmental and social controls. That tension is visible in lithium, copper and other energy-transition supply chains, where permitting timelines and ESG performance increasingly influence project credibility.
Skillings readers tracking these markets can place the issue alongside our coverage of the lithium price outlook and the wider critical-minerals supply-chain strategy.
For mine operators, the immediate task is practical: map every pile, confirm its regulatory classification, reconcile design and as-built records, test monitoring systems, and update closure assumptions. For investors, lenders and policymakers, the key question is whether those controls can be independently verified.
The September hearing is one step in that process. The larger shift is toward a mining ESG compliance model in which safety is measured not only by the absence of a failure, but by the quality, continuity and credibility of the evidence showing how risk is managed.
