Mining and processing activities generate mineral waste. Mineral wastes include:
- waste rock extracted during the mining process, and
- tailings which are the residue of process water and minerals that remains after processing.
Some of this mineral waste is chemically reactive and has the potential to form acid and metalliferous drainage (AMD). This can negatively impact water quality and the success of land rehabilitation if not identified early and managed effectively.
In implementing our control plans, we focus on characterising mineral waste and managing its storage to limit environmental impact and minimise operating and closure costs.
We manage waste rock by:
- using it as underground mine backfill
- stockpiling it where there is potential to extract metal value in the future and/or
- placing it in surface waste rock dump landforms.
We aim to minimise the amount of waste rock in surface landforms at closure. While some operations will be required to design closure strategies to manage historical legacies associated with waste rock placement, recent waste rock dumps at Rosebery and Las Bambas have been designed for closure from the outset.
Non-mineral wastes include oils and general refuse. We comply with all local jurisdictional requirements regarding waste characterisation, hazardous waste transport and management, and onsite waste disposal facility design, management and closure.