NorthParkes Airblast 1999

24/11/1999 - NorthParkes - Windblast, Airblast

On the 24th of November 1999, NorthParkes E26 Mine was in a maintenance shutdown, there were approximately 65 persons working undergound at about 2:50 pm. A catastrophic event occurred over a period of about 4 minutes, where the ore body above the cave back collapsed into the void, creating an air blast wich travelled through underground workings of the mine, in particular through the exploration drive at One Level.

The force of the air blast was such that roof bolts and metal mesh were bent, motor vehicles destroyed and four workers within the vicinity killed. Two of those persons, Ross Bodkin and Michael House were employed by North Parkes Mine, the other two, Stuart Osman and Colin Lloyd-Jones were employed by the contracting company Pontil.

Workers on other levels felt the effect of the blast but were not injured.

This accident claimed the lives of 4 people, these were: Colin Lloyd-Jones, Michael House, Ross Bodkin, Stuart Osman


1. The circumstances and causes of this event and the findings and recommendations of the inquest shall be made known to the Mining Industry through appropriate technical publications and technical forums.

2.In addition to recommendation 1 above it is recommended that the Department of Mineral Resources of New South Wales bring the findings and recommendations of this Inquest to the attention of the Mining Industry and the education establishments servicing the Mining Industry.

3. Any Mine Operator intending to employ the process of block cave mining to identify and analyse the elements of all the risks associated with its block cave operations and .develop and maintain hazard management procedures for the management of specific risks.......Management of the major hazards in a block cave mine must include recognition of the fact that these three issues are interrelated and cannot be managed as discrete elements

4. In order to establish the hazard management procedures referred to in recommendation 3, the two controls, height of muckpile and air gap above the muck pile in a block cave mine, require more specific definition.

5. North Parkes Mines install and maintain a monitoring system capable of measuring at appropriate intervals the caveback location and muckpile location and a seismic monitoring system capable of assessing the frequency, magnitude and the location of caving activity for the duration of the progression of the cave.

6. Mine design and operation. The mining industry should incorporate the following specific recommendations into all relevant codes of practice or industry guidelines for safe mine design and operation:......

7. Mine operators use their best endeavours to ensure that all underground mines have adequately assessed all risks and develop and maintain a hazard management procedure to cover all hazards associated with the mining method used or proposed to be used at the mine. The hazard management procedure shall include:..............

8. Mine operators use their best endeavours to ensure that the risk management process used at a mine satisfy the standards in the DMR’s guidelines for risk management - MDG 1010 Risk Management Handbook for the Mining Industry and MDG1014 Guide to Reviewing a Risk Assessment of Mine Equipment and Operations, subject to the review detailed in Recommendations 11 and 12 below................

9. Mine operators use their best endeavours to ensure that all risk assessments and their outcomes be incorporated in the overall safety management plan for the operation.

10 The mining industry and relevant stakeholders use their best endeavours to ensure that mines:......................

11. The Department of Mineral Resources, in consultation with the mining industry and   relevant stakeholders, review its guidelines for risk management- MDG1010 Risk Management Handbook for the Mining Industry and MDG1014 Guide to Reviewing a Risk Assessment of Mine Equipment and Operations in light of the North Parkes experience. The review should include information on: .....................

12. The Department of Mineral Resources review its publication Minerals Industry Safety     Handbook, documenting the  lessons and outcomes from this Inquiry and include:-...............

13. Universities, recognised training authorities and other educational organisations, in      consultation with relevant regulatory authorities, mine operators and professional  associations, review their courses in mining engineering, geotechnical and related fields to ensure that adequate content is given in all courses associated with mining operations, as to engineering principles, design, uncertainty and risk management. Specifically such review shall seek to ensure that, the disciplines of core risk identification and fundamental principles of rock engineering behaviour, relative to different mining methods and ground conditions is incorporated as necessary.

14. Where a new mining method is introduced by a mine owner into any mine within NSW, the Regulator should familiarise itself and relevant Officers in the core risk of such method, so that they have a good working knowledge of current best practice in that mining method, to enable them to evaluate any proposal by the mine and to fulfil its responsibilities.

15. DMR Inspectorate personnel should have a protocol for seeking, and a means of accessing specialist resources or advice, as required, in order to satisfy themselves that certain action proposed by a mine operator is suitable for the task. This means of access may be in the form of in-house resources; ability to engage independent experts directly; or  ability/authority to ask the mine to engage an agreed independent expert or second opinion.

16. Finally I recommend that further research be encouraged within and on behalf of the Mining Industry into the issues of the fundamental understanding of air blasts - air blast mechanisms, prediction and control strategies (including bulkhead design), inter-relationship with caving behaviour and rock failure mechanisms and subsequent design procedures. The outcomes from such further research should then be directed into ongoing review and refinement of the various guidelines and design processes and parameters referred to above.