Anglo American has kept its operations at the Grosvenor coal mine in Queensland suspended due to oxidation of coal and rising gas levels in the underground mine.
The company halted operations at the Bowen Basin site on May 6 following an underground gas ignition event, the first to occur in Queensland since 1994.
Anglo American metallurgical coal business chief executive officer Tyler Mitchelson said that suspending longwall mining elevated the risk of oxidation of coal, which was very low during normal operations.
The company has been monitoring gas levels to ensure the safety and integrity of the site, which have started to increase in the month following the mine suspension.
“Consistent with our risk management protocols, we made the early decision to fully restrict access to the mine when levels of certain gasses started to rise as a result of the inactivity on the longwall,” Mitchelson said.
“Over the past couple of days, we commenced a range of measures to stabilise the area.
“Once gas levels are proven to be stable, work will continue to ensure the ongoing safety and integrity of the mine.”
The company started a staged re-entry to the mine in mid-May upon receiving mine inspectorate approval to do so and after reconnecting gas monitoring equipment.
Grosvenor’s 800 employees and contractors, however, were sent home on full pay until it is safe for work to recommence.
All workers were accounted for after the accident, with five injured men sent to the Moranbah Hospital, and then later transferred to Brisbane.
Anglo American produced 540,900 tonnes at the Grosvenor longwall metallurgical coal operation during the March quarter, which represented a 47 per cent drop compared with the previous quarter’s longwall move.
The company is keeping its workforce closely updated regarding the incident and the eventual restart of operations once it is safe to do so.