Whitehaven Coal has commenced open cut mining at its Maules Creek coal mine.
The work comes just days after the first wave of new workers began at the mine.
The miner carried out two blasts last week in preparation for full scale mining.
Whitehaven CEO Paul Flynn stated that "this is an important milestone for Maules Creek and Whitehaven".
"We have been focused on delivering the Maules Creek project for all our stakeholders, including the local community, for a considerable period of time.
"With the commencement of the box-cut, the transition from construction to operations is well underway," he said.
The miner added that Maules Creek is currently on budget and schedule to deliver first saleable coal in March next year.