This position statement sets out ICMM members’ approach to the governance of tailings storage facilities (TSFs) for the mining and metals industry to minimise the risk of catastrophic failure of tailings facilities.

Tailings storage facilities at all our operations meet or exceed regulatory requirements, and we work to continually improve the management of these facilities. Planning, design, construction, operation, decommissioning and closure are carried out in a manner such that:

• Structures are stable
• Solids and water are managed within designated/approved areas
• Facilities comply with regulatory requirements
• Facilities conform to applicable standards, internal policies, industry best practices and the technical guidelines of the jurisdictions in which we operate

We have comprehensive systems and procedures in place for the safe operation and monitoring of tailings facilities that follow best practices, organized around interrelated activities that include:

1. Surveillance Technology: Dictated upon site-specific conditions and approved designs, our sites employ surveillance systems such as GPS hubs, piezometers, inclinometers, pressure gauges, remote sensing and other technologies to monitor tailings dams, abutments, natural slopes and water levels. The surveillance information is evaluated against established response levels that include pre-determined mitigation activities should trends of unusual performance arise
2. Staff Inspections: Tailings dams are inspected by trained operators and expert technical staff as frequently as several times daily, with formal staff inspections at least once per month
3. Annual External Inspections: Formal dam safety inspections are conducted at least annually by an external Engineer of Record, a fully licensed, qualified individual in the relative jurisdiction, who has their qualifications vetted by our Tailings Working Group. Independent, qualified engineers also conduct periodic reviews, with timing dependent upon the consequence classification of the facility. For all facilities, the annual inspection reports are provided to the appropriate authority in each jurisdiction
4. Internal Review: On a formal rotation basis every two to three years, we conduct internal management review of our tailings facilities. These Tailings Governance Reviews evaluate each site’s conformance with our internal tailings guidance documents and policy. In addition, informal and more frequent reviews of our facilities are carried out by one or more members of our Tailings Working Group during routine site evaluations, which assist in reinforcing the issues discussed during the most recent governance reviews
5. Detailed Third-Party Reviews: Comprehensive third-party dam safety reviews are conducted by a qualified independent tailings reviewer(s), vetted by our Tailings Working Group, every five to 10 years for active and inactive facilities. The frequency of inspection is based upon the consequence classification for each facility
6. Independent Review Boards: Our operations and projects with existing or planned major tailings storage facilities have Tailings Review Boards made up of independent experts from relevant fields, such as geotechnical, hydrogeological, hydro-technical and geochemical. These boards meet from once to several times per year, depending upon the nature of the facility and the issues being considered by the board, to conduct a third-party review of design, operation, surveillance and maintenance of our storage facilities

Each facility also has a detailed Operations, Maintenance and Surveillance (OMS) manual and Emergency Preparedness and Response Plan, both of which are regularly updated. We maintain site-specific Tailings Management Systems that conform to or exceed industry standards of practice, that demonstrate responsibility and leadership through the commitment and actions of our employees, and that are developed through consultation with communities. We continually review our facilities and procedures and are committed to maintaining the highest standard of safety at our operations.

Antamina and Fort Hills, joint venture operations where Teck is not the operator, both have Tailings Review Boards in place as well. Teck also provides senior experts to Antamina’s Tailings Technical Committee.

Teck has a Tailings and Water Retaining Structures Policy and associated guidance documentation that provide a consistent company-wide approach to how we manage the risks inherent with tailings. In addition, Teck has a companion Tailings Governance document that provides clear guidance on roles and responsibilities related to tailings management across all Teck projects, operations and legacy properties. Teck’s Health, Safety, Environment and Community (HSEC) Management Standards also include general guidance on tailings and mine waste management. These management standards, the associated guidance documents, and our adherence to them, are overseen by the Safety and Sustainability Committee of the Board.