The New South Wales Planning Assessment Commission (PAC) has given the green light to let Rio Tinto’s Bengalla mine keep running for the next 24 years.

But the approval has some contingencies.

The PAC has told the state government there will be some consent conditions for the big Hunter Valley coal mine extension.

Rio Tinto’s Bengalla open cut coal mine near the town of Muswellbrook will now undergo a $690 million “continuation project”, which will see mining activity move to the west of the town.

The PAC has imposed draft conditions relating to nearby property acquisition, noise levels, biodiversity and what to do with the giant void left when the mining is over.

The commission says it wants robust conditions to help mitigate the impacts of the mine.

It found that the original proposal did not adequately address the significant risks of the continuation, and suggested some improvements to Rio’s plan.

The PAC’s final approval will be subject to those conditions.