Recycling

When we extract minerals from rock, we create mineral and non mineral waste. Mineral waste includes mined rock, tailings and slag, which are produced at very large volumes, have only limited value, and can pose environmental hazards if poorly managed. Most of our mineral waste is placed back into mined areas or is stored in engineered on site disposal facilities.  Non mineral waste includes such materials as coal ash from power plants, specialized aluminium smelter wastes, construction and office debris and mining-related wastes such as used oil, tires, and spent chemicals.  Non mineral waste is produced in much smaller volumes and is more commonly managed through offsite disposal or recycling.

Through improvements in mine planning (see Improving performance together) we are improving the efficiency with which we extract ore and manage our waste areas. These improvements are expected to increase productivity, reduce fuel costs and lower greenhouse gas emissions as mines develop.

How we manage our waste

In order to reduce our impact on the environment with two different kinds of waste, we use a mixture of strategies:

• Mineral waste - the waste of the mined resource that remains after the product has been shipped. This includes waste rock, tailings and slag. Acid Rock Drainage (ARD) is a common environmental problem associated with chemically reactive mineral wastes.
  
  We generally manage mineral waste through responsible onsite disposal.  Where possible mineral waste is used for in pit or underground backfill, or is recyled and reused on site for other beneficial purposes.
  
• Non mineral waste - primarily auxiliary materials that support our mining and mineral processing such as tyres, oils, batteries, refractory lining and domestic rubbish.
  
  We reduce or eliminate non-mineral waste by recycling or reusing it wherever possible.

Careful management of mineral waste is critical to reduce costs while maximising the recovery of ore. Due to the large volumes of material involved any improvements in mineral waste management can have significant savings, from daily savings in reduced energy consumption through to minimising future closure costs.