The Resources Regulator will lead a causal investigation into an incident at Peak Gold Mine last month where there was an unexpected initiation of electronic explosive detonators.
The misfire incident occurred at Peak Gold Mine’s New Cobar and Chesney site on 18 May 2022. No-one was in the vicinity of the misfire and no-one was injured.
On the day of the incident, two locations were loaded for firing with electronic detonators.
The electronic detonators were placed at a development face and a stope at the mine site. The system was designed to fire simultaneously however there was a communication issue and the system would not initiate.
The shotfirer working at the development face replaced the electronic detonators at the development face with more conventional electric detonators that could be fired from the 240-volt mains firing line. The intention was to fire the development face only.
The stope shotfirer was expected to do further investigations before the stope was fired.
The development shotfirer did not disconnect the original stope electronic detonators before firing the development face.
The detonation at the development face occurred as the workers expected. However, the stope partially initiated and there was evidence of cratering and rock/emulsion ejection.
This was completely unexpected and should not have occurred due to the different firing signals required by the two different types of detonators to commence initiation.
Following notification of the incident the following notices were issued to the mining operation:
- s198 non disturbance notice of the scene and all associated blasting infrastructure including the magazine.
- S195 prohibition notice for all blasting activities on site
- S155 request for information
On 19 May 2022 inspectors from the Regulator attended the scene and undertook a site assessment. A causal investigation is underway.
The purpose of the causal investigation is to quickly understand the causes of the incident and provide timely information to the industry to reduce the likelihood of a recurrence.
An Investigation Information Release (IIR) will be published on our website within a fortnight.
