The consortium will run for five years.
Glencore attributed most of the fall to 3.7Mt to the timing of coal extraction at Hail Creek.
The coordinator-general will undertake an assessment of environmental, social and economic impacts.
Under the 18-month contract extension, Thiess will provide mine planning, design and execution.
Glencore is spending $500 million to extend operations at Mt Isa and Townsville.
Glencore's CTSCo project is Australia's most advanced onshore CCS project.
Aussie coal dominated by Swiss and Chinese, says Tinkler.
Glencore Mt Isa plant the latest east coast facility facing closure.
COVID-19 affected the demand in part of the major importing countries.
APD claims it retained the sub-surface strata and associated mineral rights.
Where temporary shutdowns are necessary, they will coincide with the September school holidays.
Coking coal production for H1 2020 of 3.7 million tonnes was 0.6Mt or 14% below H1 2019.