Rehabilitation

We have committed ourselves to making a 'net positive impact' on biodiversity at our operating sites around the world. No other company in the mining sector has ever made such a commitment.

But in order to achieve our goal of net positive impact at a site, we must first use what we call a 'mitigation hierarchy' to decrease the size of our final or 'residual' impact. 

How we use mitigation hierarchy

At a well planned and managed site, mitigation hierarchy may involve a combination of three factors:

• Avoidance - we design the sites so as to avoid encroaching on, where possible, habitats and areas of high biodiversity value.
• Mitigation - where we do have an impact, we try to reduce the size of it by, for instance, using pollution controls on water discharges.
• Rehabilitation - following disturbance, we rehabilitate the land to a form and state agreed by stakeholders.

We conduct progressive rehabilitation, wherever possible, to reduce the impacts on the environment and minimise the residual impact of the site.  Generally this is recorded at the time of closure. The length of time an operation has been running and its method of mining will influence the size of an area available for rehabilitation.

Some land is required for long term infrastructure - such as roads and processing plants - most of which cannot be rehabilitated or decommissioned until the mining operation has ceased.

The nature of the mining operation will also influence the ability to undertake progressive rehabilitation. For instance, retaining access to the ore at vertical surface mines means that most of the land remains open until mine closure.

Our results

Our 2006 results show that, 24 square kilometres of land was rehabilitated in the last reporting period, a 38 per cent increase from 2005.  Weipa and Richards Bay Minerals rehabilitated areas previously disturbed for ore access. Kennecott Utah Copper rehabilitated parts of its tailings dams, and Hunter Valley Operations rehabilitated large areas of spoil dumps.

Major contributors to rehabilitation are horizontal surface mines where rehabilitation is an integral part of the life of a mine.
We have now rehabilitated a quarter of our total footprint of 1,513 square kilometres. The remaining footprint will be progressively rehabilitated as the land becomes available.

Sixty per cent of the total land rehabilitated had been previously disturbed for ore access or were rock dumps or tailings impoundments.