Our commitment to the environment
As a primary aluminium producer, our mining, refining and smelting activities have the potential to impact the environment. Producing primary aluminium generates emissions and by products such as mine tailings, refinery residue (red mud), and fluoride and greenhouse gas emissions.
All Rio Tinto Aluminium operations, research facilities and offices are accredited to ISO 14001, an accepted international standard that sets out the requirements for an effective environmental management system. Operations proactively identify opportunities to mitigate the effects of activities. Rio Tinto Aluminium operations have the clear objective to continuously improve year-on-year environmental performance. Operations are regularly audited by independent accreditors to identify areas for potential improvement.
During 2006, Rio Tinto Aluminium reviewed the classification system for health, safety, environment and community incidents. In September, we adopted a classification scale of one to five, depending on potential severity.
The number of recorded environmental incidents in 2006 increased to 52 compared to 30 recorded incidents in the previous year. While the increase in the number of incidents in 2005 was the result of a growing asset portfolio (with the first full year of production at the Yarwun alumina refinery), during 2006 we encountered a number of challenges.
In particular, at Weipa we recorded two category four environmental incidents as a result of sewerage spills caused by problems including power outages, pump blockages, pipe blockages and pump failures. We received a penalty infringement notice from the Queensland Environmental Protection Agency as a result of these spills.
To mitigate the impact of environmental incidents, we implemented several engineering remedies and procedural changes throughout he year. We will continue to examine the root causes of all environmental incidents and where necessary make changes to prevent re-occurrence. The target for 2007 will stretch operations to achieve a 50 per cent reduction in the number of environmental incidents classified as category two (medium impact).
The target for higher category incidents will remain zero.
Water management
Water usage is an important environmental indicator, particularly in areas where there are competing interests for available water and potential impacts associated with drought conditions. Accordingly, water efficiency programmes are continually being evaluated and implemented at Rio Tinto Aluminium to increase the amount of water recycled.
During 2006, Rio Tinto Aluminium Weipa and Rio Tinto Aluminium Yarwun undertook water diagnostics to identify opportunities to conserve and recycle water where possible. In 2006 at Rio Tinto Aluminium, we used less fresh water compared to 2005. Ninety three per cent of our total water consumption was used at the Weipa bauxite mine and the Yarwun alumina refinery in Gladstone. Rio Tinto
Aluminium Weipa consumed 1.2 kilolitres of water per tonne of bauxite (kL/tonne). Rio Tinto Aluminium Yarwun consumed 3.2 kL/tonne of alumina produced.
Land management
Rio Tinto Aluminium manages over 2,500 square kilometres of land of which most is located around Weipa. As the basis for our land management plans, we aim to understand the current and potential uses of the land we manage, its ecological and social value and community expectations regarding development.
At Weipa, our objective is to minimise the mine's footprint by rehabilitating areas no longer required for mining purposes. This process brings the already mined land back to near pre-mining condition (or to a condition suitable for another agreed alternative), while mining continues in other areas. Discussions with Traditional Owners, local communities and regulators are essential as part of 'life after mine' planning. These discussions assist in determining the end use of the land and guide the approach taken for rehabilitation and revegetation.
The long term target for rehabilitating land at Rio Tinto Aluminium remains a ratio of 1:1. In 2006 at Weipa, we disturbed 1,162 hectares of new land and rehabilitated 529 hectares of disturbed land. This represents a ratio of nearly 2:1.
For Rio Tinto Aluminium Weipa's entire life span to date, we have disturbed 9,995 hectares and rehabilitated 8,898 hectares of a total land holding of 264,667 hectares. There was no land disturbed or rehabilitated at any other Rio Tinto Aluminium operations in 2006.
In 2007 our focus for land rehabilitation will remain on Weipa. During the year, as part of a partnership with The University of Queensland's Centre for Mined Land Rehabilitation we will compare Weipa's
rehabilitation with the rest of the mining industry. This ongoing partnership aims to re-establish our rehabilitation to world's best practice.
Waste management
Waste management Rio Tinto Aluminium managed operations look at the opportunities available to minimise waste such as recycling, supply and product alternatives, reduced packaging, and improved operational practices and process design. Some of the by products of the aluminium production process are recycled and others are designated as wastes requiring disposal. Potential opportunities exist to
re-use large volume materials such as red mud and Spent Cell Lining. We are investigating these options and other possibilities to minimise and preferably eliminate waste.
Fluoride emissions management
The smelting process emits fluoride which has the potential to cause harm to vegetation. Monitoring at all Rio Tinto Aluminium smelters has shown no effect on the surrounding vegetation. In 2006 fluoride emissions increased at Rio Tinto Aluminium Bell Bay, Boyne Smelters Limited and New Zealand Aluminium Smelters Limited (NZAS). Rio Tinto Aluminium smelters report their emissions in further detail.