Gympie was suspended from ASX trading today, at the request of the company, after the heating had worsened over the past few days.

“The mine’s gas monitoring equipment has detected abnormal gas levels in the mine. It appears that a mined-out area adjacent to the current SL4 longwall panel has developed a heating which indicates increased potential for spontaneous combustion of in-situ coal,” Gympie said in a statement on December 24.

Following the discovery of the problem the mine’s Safety Management Plan was activated and all personnel were evacuated from the mine.

Expert personnel and advisers, as well as the Mines Inspectorate and Union representatives, have been called to the mine to participate in the development of a plan to control the heating.

Gympie said management had already implemented actions to extinguish the heating. This may include drilling of a borehole from the surface and injecting an inert gas down the borehole to the point of heating.

“This process would take at least one week and the mine would likely be idle for some weeks,” Gympie said.

No persons will re-enter the mine until a safe working environment has been re-established, the company said. In the meantime, most production personnel have been requested to take available leave.

Customers were being advised and some shipments will need to be re-scheduled.

Southland is located in New South Wales in the Newcastle coal field and extracts from the 3.5 metre Greta coal seam.