In its efforts to expand its Warkworth coal mine in New South Wales, Rio Tinto is leaning on the support it has received from the community and the 900 submissions backing the project.

The Australian reported that Rio Tinto has been working to expand the Hunter Valley mine since the Land and Environment Court put the brakes on plans earlier this year, after Rio Tinto had already received government approvals to proceed.

Rio Tinto has appealed against the court decision. The company lodged a new application for a smaller expansion in November, allowing it to access 350 m of land to keep its production at an economic level.

Rio Tinto's subsidiary Coal & Allied said that more than 900 submissions supporting the project were received by the Department of Infrastructure and Planning against 140 opposed to it.

Rio Tinto Coal Australia managing director Chris Salisbury said the number of positive submissions sent a clear message that people and businesses valued and depended on the Mount Thorley Warkworth operation.

"In addition to providing the work for more than 1,300 employees and contractors, the operation spent more than $600 million with close to 1,000 suppliers last year," he said.

"Securing a timely approval is critical to the Mount Thorley Warkworth mine remaining economically viable . . . this modification will give us time to look at options to provide a longer-term future for the mine."

The state government has recently changed the regulation for mine approvals and weight will now given to the economic benefits, including job creation, of the operation.

The Hunter Central Rivers Alliance, which comprises of 40 community groups, complained yesterday that the NSW government and Rio were “colluding” to rush the expansion through the approval process.

The group complained about Rio submitting a new, smaller, expansion plan while it waited on the outcome of the legal challenge on the NSW Land and Environment Court's decision to stop the wider expansion.

"The government gave the public only two weeks to comment on the proposed mine expansion, after springing it on us without any warning," John Krey, from the Bulga Milbrodale Progress Association, said.