Dealing With Dust In Port Hedland, Western Australia
Low-frequency microwave moisture analyser in use.
Few, if any, environmental issues in the Company's Iron Ore operations (BHP Billiton 85 to 100 per cent) at Port Hedland have a higher priority than dust management. As reported in previous case studies, this issue is the community’s principal industry concern, particularly among households and businesses near the port area and our Nelson Point facilities.
Against this background, we have made a formal commitment to reduce ambient dust levels and improve water use efficiency as part of a major business growth strategy. The planned benefits from the program in place include:
- Real evidence of reduced dust levels
- A comprehensive approach to research and management of dust issues
- Extensive community and government environment, health, planning and development agency involvement
- Improved public engagement, reporting and information
- Incorporation of dust control priorities in planning
- A complementary focus on water use efficiency.
New targets have been set for improvements in air quality, community amenity, operational response and water use efficiency (see table and graph below).
The Mayor of Port Hedland, Stan Martin, commented: "Dust has been an issue in Port Hedland for more than 40 years. It won’t be solved overnight, but I think the program put in place by BHP Billiton is making some progress. At the same time, people have a much better understanding of the problem and the way it is being tackled."
The Challenges And Opportunities
Company plans for business growth create a combination of challenges and opportunities. The challenges come from the inherent potential for increased airborne dust levels as production and shipping increases. The opportunities are based on the introduction of new technology and operating strategies for continuous improvement in dust management per tonne of production.
The health-related challenge associated with dust is to understand how iron ore dust compares with other dusts in relation to potential impact on human health. To this end, over the past two years we have been assisting a three-part study with the Western Australian Department of Health (DoH) and the Department of Environment and Conservation (DEC) to further this understanding.
Results to date from ongoing research have indicated a low level of any health risk from dust in Port Hedland. The draft literature review, which includes a review of international literature, has theorised that there may be vulnerable groups within the population that may experience ‘short-term’ effects, such as irritation of the airways, as a result of exposure to both fine and coarse particulate matter. It is our intention to continue to work collaboratively with the DoH and DEC and to independently pursue research to further our scientific knowledge and understanding of any potential health impacts associated with our operations.
How We Are Doing It
Enclosed car dumpers reduce dust emissions.
Our commitment to reduce ambient dust levels and improve water use efficiency has demanded a comprehensive approach based on the following key initiatives:
- A new environmental agreement with the state government to meet specified dust targets
- Capital projects:
- Moisture conditioning technology.
- State-of-the-art crushing and screening equipment near our Newman mining operations
- enclosed car dumpers
- Direct loading of ships
- Decommissioning and removal of old stockpiling and processing facilities
- Rehabilitation of former stockyards
- Workforce education
- Additional monitoring equipment
- A 'cleaning and greening' program
- Water recycling and conservation programs
Technology Advances
A key advance in dust management has been the development and refinement of iron ore moisture conditioning. Moisture helps to reduce dust; however, too much moisture makes handing difficult and inefficient. It also wastes a precious resource in the arid Pilbara region.
To find the right balance, our own technology centre and the CSIRO have combined to develop reliable tests, effective spray systems and low-frequency measuring technology for optimum moisture regimes.
Involving The Community
We have involved local residents and business operators through:
- Detailed community surveys and consultation to identify key issues, impacts and options for improvement.
- Workshops to set priorities and develop communication, information and response strategies
- Information packs and public reporting initiatives.
Community representatives set the following priorities:
- Reduced dust emissions
- Central business district clean-up
- External building cleaning
- Landscaping and tree planting
- Car cleaning and covers.
Setting New Targets – The Way Ahead
The following table outlines our dust and amenity performance targets.
| Performance Aspect | Target |
|---|---|
| Air quality related – long-term average | Improvement in the annual average number of airborne particles with a diameter less than 10 micrometres (PM10) monitored at the Port Hedland monitoring site to a long-term target of 30 micrograms per cubic metre (µg/m3) (see graph below). |
| Air quality related – short-term average | Improvement in the 24-hour average PM10 monitored at the Port Hedland monitoring site to a long-term target of 70 µg/m3 with less than 10 exceedences per year. |
| Amenity related | Improvement in the annual average total suspended particles (TSP) monitored at the Port Hedland monitoring site to a long-term target of 65 µg/m3. |
| Amenity related – community perception | Improvement in amenity (relating to the Company's iron ore dust) within the western end of Port Hedland. |
| Amenity related – community satisfaction | Improvement in community satisfaction with Company management of dust impacts. |
| Operational response | Effectively employ real-time dust event mitigation process. |
| Water use efficiency | A 10 per cent reduction in fresh water consumption per tonne of iron ore (produced) during the period 2006 to 2012. |
Going Forward
We will be continually implementing and monitoring our comprehensive dust management program to reach the new targets.
