Benambra Mine, Benambra, Victoria, Australia

Department of Primary Industries (DPI)

2005 - 2006

Situation

From 1992 to 1996, the Benambra Mine operated as an underground base metal mine producing zinc and copper concentrate. In 1996, the Mine was placed into administration and mining operations ceased immediately without the undertaking of any environmental rehabilitation.

The unplanned closure of the mine created an array of environmental problems and in 2005, the DPI engaged us to undertake design and documentation of a rehabilitation plan for the entire site, including the tailings dam.

We had been involved with the Benambra Mine since the late 1980’s, having undertaken site investigation for the original tailings dam and subsequent design, documentation and construction management of the tailings dam embankment.

The DPI’s objective was to achieve a stable and environmentally self-sustaining site that conformed to industry best practice and met stakeholder, community and legislative requirements.

Solution

Our rehabilitation plan for the site covered a range of components, including:

  • Re-engineering the Tailings Storage Facility (TSF) to satisfy long-term closure design criteria and minimisation of contaminant production;
  • Creation of an anaerobic wetland, downstream of the TSF;
  • Disposal of remnant sulphidic waste into the TSF;
  • Removal and disposal off site of all hydrocarbons, hydrocarbon contaminated soils, chemicals, plastics and steel waste;
  • Crushing and co-disposal of all concrete; and
  • Landscaping and re-vegetation of the mine site and associated access roads.

We engaged and worked collaboratively with environmental, contamination and geochemical consultants as well as the DPI to achieve mutually acceptable solutions that met the DPI brief.

Since the project involved the expenditure of considerable public funds, a detailed design address was presented to all stakeholders, including State Government departments, Local Government Shires and Councils and other affected parties. The address presented the issues at stake and the design solutions in detail, but in a manner readily understood by a lay person. Any and all questions raised by the stakeholders were addressed either by the DPI and/or ATC Williams.

A similar presentation was delivered to contractors bidding on the project, prior to a tour of the site during the tender period.

Outcome

Despite the mine’s remote location, the strict environmental requirements and sometimes adverse weather, the project was successfully completed within a 4.5 month time-frame in 2006.

The project was subsequently recognised by the industry as an outstanding achievement.

Awards:

  • 2006 - The Victorian CASE Earth Award for ‘Environmental Excellence.’
  • 2006 - The National CASE Earth Award for ‘Environmental Excellence.’
  • 2006 - The Australian Mining Magazine’s Australian Mining Prospect Award for ‘Excellence in Environmental Management.’

Similar Projects:

For further information please contact:

Charles Vuillier on 0435087562 or via email at charlesv@atcwilliams.com.au