Olympic Dam expansion approval
Frequently asked questions
What expert advice was the decision informed by?
To ensure the decision was based on the best available scientific information, the proposal was subjected to independent expert reviews—including by Geoscience Australia, the Australian Radiation Protection and Nuclear Safety Agency, and the Supervising Scientist.
These reviews made recommendations to ensure that the proposal meets world best practice environmental standards for uranium mining, and that the risks to the environment, including groundwater and native species, can be acceptably managed.
The assessment involved extensive public consultation, including more than 4,000 submissions on the published assessment documentation. In making his decision, the minister took public comments made on the project environmental impact statement into consideration.
What are the key approval conditions?
The approval conditions require BHP Billiton to strictly manage or avoid any environmental impacts, not just during operations, but well beyond the life of the project.
The conditions apply to all parts of the project, including the proposed desalination plant in the upper Spencer Gulf, and will ensure that the gulf and its marine life—including the giant cuttlefish—are protected.
The measures that the company will use to achieve these goals must all be detailed in an extensive and thorough environmental management and monitoring program, which must be approved by the minister before work can begin.
Ongoing monitoring will ensure that any issue can be tackled immediately, and the program must be reviewed every three years to ensure it remains effective over time, and takes account of the latest scientific information.
BHP Billiton must also do a comprehensive review every 10 years to ensure they are using the best practicable technology to minimise environmental impacts and risks.
How long is the approval valid for?
The approval is valid for 50 years, allowing 10 years for progressive mine closure and rehabilitation after 40 years of mining and processing.
Has BHP Billiton commenced work on the expansion?
BHP Billiton has commenced some preparatory works such as re-alignment of roads, site works for machinery lay-down areas and maintenance facilities, and the expansion of the Olympic and Roxby villages to accommodate additional workforce numbers. The company cannot commence removing overburden (the material located above the ore body) until the minister has approved a comprehensive environment protection management plan.
How will radiation be minimised?
The Australian Government is committed to world best practice environmental standards in uranium mining.
BHP Billiton must ensure radiation remains below regulatory limits set by the Australian Radiation Protection and Nuclear Safety Agency throughout, and well beyond, the life of the project.
Tailings and rock storage facility
Extensive modelling and testing, which has been reviewed by the South Australian Environment Protection Authority and the Australian Radiation Protection and Nuclear Safety Agency, confirms that radiation at the rock storage facility will remain at less than half the regulatory limit.
Seepage will be neutralised within four metres when it comes into contact with the naturally occurring limestone below the tailing and rock storage facility. The underlying limestone is up to 60 metres deep, so provides a substantial buffer against seepage.
Post-closure
Risks from post-closure radiation will be minimal, but before mining can start, BHP Billiton must submit a closure plan describing international best practice measures to tackle long-term residual risks from radiation.
When the mine is closed, BHP Billiton must cover the tailings storage facility to protect the environment in the very long term, including from erosion.
A person continuously exposed to radiation levels after the mine closes would receive less than one-fifth of the regulatory limit of radiation (0.2 milliSieverts per year, compared with the regulatory limit of 1 milliSievert per year).
If at any time it becomes apparent that the company has not set aside enough money to close the mine according to the approval conditions, the minister can demand a bond to ensure the future cost of rehabilitation and closure is met.
How will the impact of seepage be minimised?
The company has designed the tailings storage facility to minimise seepage, including by recycling as much of the liquid waste as possible, building larger cells with greater evaporation capacity, and installing a liner beneath the central decant system.
Modelling and testing has shown that seepage will be neutralised within four metres when it comes into contact with the naturally occurring limestone below the tailings and rock storage facility. The underlying limestone is up to 60 metres deep, so provides a substantial buffer.
If any seepage does move away from the tailings facility, it will move towards the pit, where it will be contained.
As a precaution, the approval conditions require BHP Billiton to continue ongoing monitoring and groundwater modelling to show that the seepage is acceptable, and contained.
How will risks of site and soil contamination be minimised?
BHP Billiton must manage radiation exposure and site contamination during operations and well beyond the life of the project.
The company must develop criteria that clearly specify how it would investigate and respond to a leak or spill for each type of contaminant.
The company will be required to report material incidents and fully fund all activities needed to repair any leaks or spills.
How will groundwater be protected?
The approval conditions will ensure groundwater, including the Yarra Wurta springs and Great Artesian Basin, is protected from significant adverse impacts of water extraction or seepage.
Stuart Shelf/Andamooka Limestone/Tent Hill aquifers (drawdown)
The approval conditions require ongoing monitoring and plans for a response to residual risks.
BHP Billiton must do further research to add to understanding of the hydrogeology of the Stuart Shelf, including recharge mechanisms, and impacts to the regional groundwater system from the open pit.
Great Artesian Basin/Yarra Wurta springs
Expert advice from Geoscience Australia confirms there are no, or very low, risks of impacts on the Great Artesian Basin.
There is strong existing evidence that the Stuart Shelf and the Great Artesian Basin are not connected. This conclusion is supported by the expert advice.
But if a connection did exist, modelling shows that pressure in the Great Artesian Basin would not be affected. This is because even a worst-case drawdown would still maintain a positive flow to the Great Artesian Basin.
As a precaution, BHP Billiton must further investigate the hydrogeology of the Yarra Wurta Springs, the Stuart Shelf, and the area between the Stuart Shelf and the Great Artesian Basin—the Torrens Hinge Zone.
This information must be used to further improve and validate a regional groundwater model to ensure a full understanding of the aquifers' environmental values and sensitivities, so that risks can be avoided.
If the minister is not satisfied that the level of risk is acceptable, he can require additional measures, including a reduction of water extraction.
Improved regional groundwater models will also be essential for future decisions on water allocations.
Will further extraction from the Great Artesian Basin be allowed?
The water needed for the expansion of the Olympic Dam mine will come from the desalination plant at Point Lowly.
BHP Billiton has an existing licence from the South Australian Government for water extraction from the Great Artesian Basin. The company cannot extract more water under that licence for the expansion.
But extra conditions require BHP Billiton to do further research to gain a greater understanding of groundwater in the area, and to put in place a response plan, should any water extraction cause significant adverse impact to mound springs.
How will birds be protected?
The approval conditions require BHP Billiton to put in place measures to reduce impacts on birds, not just on the expansion, but on existing facilities.
This includes preventing bird access to surface water with netting or other barriers, and establishing other ways of deterring birds, such as real time monitoring so that flocks of birds approaching can be quickly dispersed.
The company must phase out the use of evaporation ponds as soon as practicable, and ensure bird deaths are reduced each year.
BHP Billiton has also made design changes to further reduce impacts on wildlife. For example, evaporation ponds won't handle excess liquid waste, which will remove large open bodies of water.
How will the impacts of the desalination plant on marine life and the giant cuttlefish be minimised?
Extensive modelling—which was done under various seasonal and tidal conditions and has been reviewed and confirmed by independent experts—has shown that discharge water from the plant would disperse rapidly, well before it reaches any areas of significant marine habitat.
The approval conditions specify that the desalination plant must not result in significant adverse impacts on marine habitats and species, including the giant cuttlefish.
Before any work can begin, BHP Billiton must do further testing and modelling over 12 months and under various flow scenarios, with the help of an expert panel, to help determine final dilution thresholds and to demonstrate the diffuser will be able to meet those thresholds under all conditions.
Conservative maximum limits for the brine dilution have been set (1:70 at 100 metres from the diffuser, and 1:85 at the nearest cuttlefish habitat), and modelling has shown that most of the time the brine will be three times as dilute as those limit (mostly 1:258, and at worst case 1:107).
If the discharge water dispersion from the plan goes over a certain level, or unacceptable impacts are detected, BHP Billiton will stop discharging until the issue is resolved.
An environmental management and monitoring plan must describe how impacts will be minimised, and the measures that will be in place to avoid salinity changes in the upper Spencer Gulf.
This plan must be reviewed every three years, to ensure it remains effective, and takes account of the latest scientific information to protect the environment in the upper Spencer Gulf.
Throughout the life of the project, BHP Billiton must monitor giant cuttlefish population abundance and distribution to improve our knowledge and management of the species.
Construction can only take place outside of the giant cuttlefish breeding season, and the outfall pipe must be installed by tunnelling to avoid disturbance to the sea floor.
Were greenhouse gas emissions considered?
The Australian Government has a clear market-based policy to reduce greenhouse gas emissions, and BHP Billiton has committed to reducing emissions by 60 per cent from 1990 levels by 2050.
The South Australian Government is requiring the company to develop and annually review a greenhouse gas and energy management plan to set interim targets and measures towards achieving this goal.
Will transport of copper and uranium be safe?
Given the low levels of radionuclides in the concentrate, which are well below regulatory limits, risks of radiation doses to people on the travel route are negligible.
But as a precaution, BHP Billiton must ensure there will be no environmental impacts from transporting copper and uranium. Radioactive material must be safely transported in enclosed wagons, stored in sealed sheds, and loaded into dedicated ships using an enclosed conveyor system.
How will the impact of the infrastructure corridors be minimised?
Of all the options BHP Billiton considered, the chosen infrastructure corridors for the water pipeline, electricity pipeline, and a rail line are those that minimises environmental and heritage impacts.
In some cases, BHP Billiton must develop management plans outlining how impacts on heritage and archaeological sites and sensitive areas, such as springs, will be minimised, and no construction can begin until the minister has approved them. These plans must show adequate consultation with affected Indigenous groups.
The corridors will be revegetated following construction.
How will dust be minimised?
Impacts on air quality will be strictly regulated and monitored by the South Australian Government under state law.
BHP Billiton must make sure that dust is kept to a minimum and has no adverse health impacts on nearby residents. How the company will do that must be demonstrated in an air quality management plan.
This includes through a real-time dust and weather monitoring system to predict and monitor dust concentrations, and ensure action can be quickly taken if limits are exceeded.
The company must continue to engage with the community and local health services, and keep abreast of new information to ensure the monitoring and response plans stay up to date.
How will unavoidable impacts, such as land clearing, be offset?
The vegetation to be cleared is widely distributed across the region, so the impact of this clearance on nationally protected matters is acceptable.
BHP Billiton must provide an offset area of about 140,000 hectares—eight times the projected clearing associated with the project.
The company will also be required to contribute to biodiversity conservation priorities, landscape scale linkages, the protection and recovery of threatened species, and programs for environmental research.
BHP Billiton will also provide continuing financial, scientific, managerial, and professional support for the Arid Recovery site.
What if BHP Billiton doesn't comply with the conditions?
BHP Billiton will be held accountable if they don't comply with the strict conditions imposed on this project.
The company must develop an environment and monitoring program that sets strict early warning limits to ensure immediate action can be taken if any of those limits are exceeded.
The plan will drive continuous improvement and must be reviewed every three years to ensure it remains consistent with scientific developments and best practice.
The company must also review its technology every 10 years so that technological improvements can be introduced to reduce the project's environmental impact.
Were social impacts considered?
In making his decision, the minister considered the potential social impacts of the proposal, but did not impose conditions relating to South Australian Government and local government responsibilities and to commitments made by the proponent.
BHP Billiton has committed to developing a social management plan to identify areas for action, including targets for local employment, workforce accommodation, and strategies for dealing with rental prices and availability.
BHP will locate the camp for construction workers away from Roxby Downs, and will prepare a masterplan for Roxby Downs.
Where will the uranium be exported to?
The Australian Government only allows the export of uranium mined in Australia to countries where it will only be used for peaceful, non weapon and non-military purposes.
How was duplication between governments reduced?
The Australian, South Australian and Northern Territory governments have worked together to share expertise and to ensure conditions provide a very high level of environmental protection.
Will the conditions apply to existing mining activities at Olympic Dam?
Yes. Through this approval, the minister's conditions will apply to the entire operation.
Where can I find more information?
To get more information on this project, including the full conditions, go to the:
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