South32 said it has recommenced production at its Appin metallurgical coal mine in Australia following a review of operating procedures.
Longwall 707 restarted production today, ahead of the return to a two longwall configuration in the December 2018 quarter.
"We have completed a detailed review of Illawarra Metallurgical Coal's operating systems and processes to address the unacceptable levels of performance that have been achieved as the Appin Area 9 project ramped-up to capacity," chief executive Graham Kerr said.
"Longwall utilisation rates of 30% to 40% are significantly below industry benchmark levels and an opportunity exists for us to sustainably improve productivity in order to maximise the value of this high quality, long life resource."
Illawarra Metallurgical Coal produced 819kt of coal during the September 2017 quarter, including 494kt of metallurgical coal and 325kt of thermal coal.
At 9:14am: (LON:S32) South32 Limited share price was -0.75p at 190.5p