Tailings Dams and Residue Storage Area Management
Alcoa is an industry leader in the management of tailings and residue storage. We have rigorous protocols in place to supervise the design, construction, operation and closure of storage impoundments that have been developed over decades of safe operating practice. Active, inactive and closed facilities are managed through a governance structure with global oversight, annual independent third-party inspections as required by regulation, long-term management plans including capital needs and clearly defined location, functional and Corporate responsibilities.
Our protocols also require use of suitable measures to prioritize our activities based on potential risks and consequences and, where appropriate, the development of effective emergency response plans. And, of course, Alcoa’s corporate culture encourages and values transparency and reporting.
Aligned with our commitment to safe, sustainable operations, Alcoa has also led new industry and company improvements in the management of impoundments. Some examples include:
- Storage of bauxite tailings within the mined footprint to reduce disturbance of land;
- Progressively moving from traditional wet storage to solar drying and stacking, where practical, which significantly reduces the potential for impacts on the surrounding environment (alumina refinery residue only);
- Bauxite residue storage areas are typically engineered embankments and are either clay/bentonite lined or have a synthetic liner, or both;
- Underdrainage systems to reduce the water pressure on the embankments; and
- Residue filtration technology, like at our Kwinana and Pinjarra refineries in Australia, which reduces the moisture content of alumina refinery residue sufficiently to allow for more conventional ways to handle materials, like using conveyors and stacking
During 2022, Alcoa has revised the consequence categories of our tailings facilities in accordance with the Global Industry Standard on Tailings Management (GISTM) - ANNEX 2 - Table 1: Consequence Classification Matrix. These will be confirmed by Engineer of Record at each location in 2022/23.
In each case, it is important to note that the applicable rating system provides a classification of the potential consequences of a catastrophic failure, not the likelihood of failure.
Explore our inventory of bauxite mine tailings and alumina residue storage facilities
An interactive, searchable inventory of our bauxite mine tailings and alumina residue storage facilities is available. Note: the list is subject to change as facilities are developed, closed, or otherwise move through their lifecycles. This database was last updated on July 2022. The next annual scheduled update is July 2023.