Tailgate Infrastructure Contributes to Longwall Methane ExceedanceMines safety alert no. 379 | 16 September 2020 | Version 1
Power to a longwall face was tripped by an automatic methane sensor located at the tailgate. The responsible ERZC conducted an inspection to identify the source of the methane. During the inspection in the area of the tailgate shields, the ERZC detected greater than 2.5% of methane.
Purpose of this alert
- Draw attention to the occurrence of a serious incident in the mining industry.
- Increase risk awareness.
- Promote mines to examine and check that their controls are adequate.
How did it happen?
An investigation into the source of the methane was conducted. It was determined the discharge end of a pipe range delivering stonedust into the tailgate, was close enough to the faceline for the discharging stonedust and compressed air to disrupt the goaf stream. This caused methane from the goaf stream to accumulate on the face around the tailgate shields.
Corrective actions were taken to eliminate this, following which the ERZC was able to take effective action to dilute the methane to an acceptable level. The mine is investigating to identify all the contributing factors that caused this methane event.
SSEs and UMMs should review maintenance practices for tailgate infrastructure installations and ensure gas behaviour in and around the tailgate is managed to an acceptable level of risk at all times.
The investigations are ongoing and further information may be published as it becomes available.
The information contained In this publication is based on knowledge and understanding at the time of writing.
Authorised by Peter Newman - Chief Inspector of Coal Mines
Contact: Stephen Smith, Regional Inspector of Mines, +61 7 4936 0120 Stephen.Smith@rshq.qld.gov.au
Issued by Resources Safety & Health Queensland