The NSW Department of Planning released a 66-page report yesterday endorsing the project, which will go to the government’s Planning Assessment Commission for approval or rejection.

Ashton wants approval to lift production from 5.45million tonnes a year to 8.6million tonnes a year for at least seven years.

It says it will spend $83million developing the mine, which will provide continued employment for 160 mineworkers.

The department says Ashton owns 49 of the 56 properties in Camberwell village, but it acknowledges the mine extension would have ‘‘significant’’ adverse impacts on another eight private properties in or near the southern end of the village.

The department says Ashton has changed its plans in response to submissions to allow another 200 metres of buffer between the mine and the village but this and other concessions are not enough for Camberwell residents Deidre Olofsson and Wendy Bowman, who both spoke out against the project yesterday.

The department says Ms Bowman’s property covers almost half of the land needed for the proposed Ashton South East open-cut mine.

‘‘To date, Ashton has been unable to purchase [the] property,’’ the department’s assessment says. ‘‘Without this property, the project is not economically viable and would not proceed.’’

Ms Bowman said yesterday that she had no intention of selling her property and while the departmental assessment talked of ‘‘requirements to acquire properties significantly affected by noise and dust’’ she did not believe she could be forced into selling.

Mrs Olofsson, who is involved in a legal battle over Ashton’s access to Camberwell Common, said open-cut mining was destroying the Hunter Valley.