Anglo American is considering longwall automation as a way to improve safety at the Grosvenor coal mine in Queensland.
Anglo American’s metallurgical coal business chief executive Tyler Mitchelson said the company had invested considerably in progressing the automation of its longwall equipment, and expediting this work would be part of the solution to reducing risks in underground mining.
The company is set to begin with a pilot study at the Moranbah North mine in Queensland to improve its site methane management controls.
Anglo American will use pressure sensors at Moranbah North to remove power from the longwall face as an additional control should a significant overpressure event occurs.
Mitchelson said while pressure sensors were already in use today across the industry, they had not been integrated for this particular purpose.
“It is unacceptable that five of our colleagues were seriously injured on 6 May and we will ensure that all relevant learnings from investigations under way and the Board of Inquiry are incorporated across our business,” he said.
Anglo American noted that though the source of the ignition had not been determined, there was a significant and unusual overpressure event on the day of the accident, where a large amount of methane was released into the longwall area. Seconds later, a brief ignition occurred.
There were also no non-compliant methane readings in the longwall area in the hours leading up to the incident.
“Since 2016, we have invested around $230 million on gas drainage and gas management activities at Grosvenor mine,” Mitchelson said.
“Despite this investment and extensive controls in place to prevent an underground ignition of methane, we need to further improve our controls to respond to the specific combination of factors of an unusual and large overpressure event in the vicinity of the longwall with a potential ignition source.”
Mitchelson reaffirmed that mining at the Grosvenor mine would not resume until it was safe to do so.
The Grosvenor workforce has remained on full pay since the accident.
Four of its five injured employees have been released from hospital. The fifth employee remains in a stable condition.