The mine extension would also secure employment for more than 230 employees and allow the mine to produce about 71 million short tons, Peabody president - Australia George J. Schuller Jr said.
"Not only does that improve safety for our operators, it enables faster haulage speeds of our high quality reserves," he said.
"We are extremely pleased to be able to continue to provide employment for people in regional and remote locations."
Federal Resources Minister Matt Canavan said Australia remained the go-to source for the world's met coal supplies, and North Goonyella was a benchmark mine providing some of the world's highest quality hard-coking coal.
"It's exciting to see projects like Goonyella South continuing to fortify Australia's reputation for the high quality coal required for steelmaking in emerging cities," Canavan said.
"This mine produces premium quality coking coal for steelmaking and meets a strong demand for growing economies in Asia.
"The latest Queensland Resources Council State of the Sector report shows very healthy investment in projects in the Bowen Basin and a surge in greenfield exploration. Jobs in the Mackay region grew by 7.5% in the year to April 2018."
QRC CEO Ian Macfarlane said Peabody had longstanding relationships with Indian steelmakers and a recent report from the Office of the Chief Economist highlighted the growth in metallurgical coal exports to India - increasing 22% over the past 12 months and forecast to overtake China as the world's largest importer of metallurgical coal by 2020.
"The Indian steel story will continue to grow along with its urbanisation story," Macfarlane said.
"The Queensland resources sector can help meet the needs of growing economies, and create jobs and investment here in Australia."