Peabody Energy intends to permanently seal the area where high methane levels have been concentrated after it reported fire in its North Goonyella mine.
Chinese copper demand has been so strong in the past few months that top producer Codelco has almost sold out of supplies for next year, well ahead of schedule.
In August, BHP had shut an acid plant following a boiler tube failure, disrupting copper processing. Underground mining at the site continued as normal.