 |
|
|
|
|
|
|
Bauxite Residue
Alcoa's alumina refineries in Western Australia process bauxite ore mined in the nearby Darling Range. The refineries extract alumina from the ore and the remaining material, consisting primarily of iron oxides and quartz, is stored in Residue Storage Areas. Around two tonnes of residue are produced for every tonne of alumina extracted. The residue does contain some residual alkalinity, hence the storage areas are lined to reduce the risks of seepage to the groundwater. "Wet disposal” residue storage practices were adopted during the 60’s and 70’s, whereby residue was placed in large storage areas where it settled slowly, and water was recycled to the refinery. Development work began in the early 1980’s on improved storage techniques and in 1987 "dry stacking" was adopted. This process produces a thickened residue which is spread in layers over storage areas. Additional water is removed through a combination of drainage and evaporative drying. Each layer is dried to the point where earthmoving equipment can move across the surface. Dry stacking of residue is now fully operational at all three of Alcoa’s Western Australian refineries, and is now being adopted by other minerals industries as best practice. The advantages include reduced environmental risk, more stable landform for immediate rehabilitation and a wider range of potential land uses for storage areas in the future.
Wagerup Long Term Residue Management Strategy
The Wagerup alumina refinery's extensive community involvement programme was recently strengthened with the formation of a working group to be consider the revision Wagerup's Long Term Residue Management Strategy (LTRMS). The LTRMS is designed to inform both government and the wider community of Alcoa’s long term residue planning and management strategies.
By involving community and government stakeholders in the development of the updated LTRMS, the concerns and queries of the local community, local Government and regulatory authorities are considered in the planning phase and Alcoa’s responses to these issues are transparent and documented. The working group comprises members of the local community, state and local government and Alcoa who will consider and provide advice on long term and strategic issues in residue management.
As part of the group's commitment to ensuring the outcomes of its deliberations are widely available, meeting reports will be published on this site. In addition, the outcomes of meetings and details of future meetings will be published in the Harvey Reporter newspaper, and meeting reports placed in the Waroona and Harvey libraries and Yarloop Learning & Drop-In Centre.
For more information about the community involvment process, please contact independent facilitator Leigh Hardingham on 0427 943 879 or Alcoa community relations officer Jodie Read on 9733 8620.
Meeting 1 - 19 September 2005
Meeting 2 - 10 October 2005
Meeting 3 - 31 October 2005
Meeting 4 - 21 November 2005
Viewing documents in PDF format requires Adobe Acrobat Reader, which is available as a free download from the Adobe Web site.
|
|
|
|
|
