The Rix's Creek South Mine, northwest of Singleton, will stay open until 2040, after a decision by the state's Independent Planning Commission was announced on Saturday.

NSW Planning and public spaces minister Rob Stokes said the decision - which will allow the mine to be expanded - will secure almost 300 jobs.

The matter had been referred to the commission due to some local opposition but it was given the green light after what the three-person panel described as careful consideration of "all the evidence and weighing the community's views".

Factors considered included noise, visual and heritage impacts.

On concerns around greenhouse gas emissions, the commission said these had been "adequately minimised as far as practicable".

It added that the approval is conditional upon owners Bloomfield Collieries Pty Ltd taking all reasonable steps to improve energy efficiency and reduce emissions over the next 21 years.

Other positives around the application include "economic and social benefits as a result of employment opportunities and revenue to the State", the commission said in its decision.

Mr Stokes welcomed the decision as "great news for the people of the Upper Hunter and the community of Singleton".

The publication followed an announcement on the issue being mistakenly revealed eight days ago due to an "administrative error", the commission said.

Australian Associated Press