News

Investigation over unexpected misfire event

unexpected misfire

A casual investigation is underway into an unexpected misfire incident that occurred at Peak Gold Mine’s New Cobar and Chesney site in NSW on May 18.

No-one was in the vicinity of the misfire or injured as a result of the blast, which occurred from an unexpected initiation of electronic explosive detonators.

The cause of the incident was a communication issue between an electronic detonator at a development face and a stope at the mine site, both of which had been loaded for firing.

The system was designed to fire simultaneously; however, the system would not initiate due to an unknown communication issue.

The shot-firer working at the development face replaced the detonators with a conventional detonator that could be fired from the mains firing line, with the intention of firing the development face only.

The stope shot-firer was expected to do further investigations before the stop was fired to assess the problem, but the original stope electronic detonators were not disconnected before the development face was fired, causing the unexpected misfire.

The stope partially initiated, with evidence of cratering and rock ejection, which should have not occurred due to the different firing signals required by the two different types of detonators to commence initiation at the stope.

Following notification of the incident, three 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

Reflecting on hazards and workplace compliance, the NSW resources regulator spoke on these outcomes in the quarterly safety report released for January to March 2022.

“As a high-hazard regulator, we focus on compliance with legislative requirements associated with principal and other high-risk hazards, including mechanical and electrical energy and explosives,” the report stated.

“‘Fires or explosion’ are principal hazard classifications that feature regularly in incident notifications to the Regulator.”

Send this to a friend