About two and a half weeks ago during the scheduled longwall move, an area of the mine began registering higher gas levels. The mine also has recorded slightly elevated temperatures caused by low-level oxidation of some coal.
Mine management removed people from underground, contacted the Queensland Mines Inspectorate and industry experts, and began mobilising resources to correct the situation.
Steps taken have included pumping nitrogen near the face to reduce levels, with recent indications that process is yielding success with current gas levels below their peak, according to Peabody President - Australia George Schuller.
"The health and safety of employees is always the number-one priority at Peabody," he said.
"Our gas monitoring and safety systems are designed specifically for these types of events and detected the elevated levels of gas in a timely manner.
"We will continue to conduct our response efforts in a safe and sustainable way, with our employees returning underground when it is safe to do so."
Peabody said it is well over halfway through the two-month longwall move at this point, with the majority of major equipment already transferred and 78 shields remaining to be moved.
Services such as power, ventilation and normal water management activities in the mine continue, and the mine is shipping from inventories.
Prior to this time, the company had been trending to the upper end of its 2018 metallurgical coal sales volume targets, and those targets have not been revised.
