The court action follows a separate Land and Environment Court hearing in June during which a senior NSW Office of Environment and Heritage officer conceded there had been mine subsidence in the area that included the significant site.

In a summons lodged with the court last month by Robert Lester, on behalf of the Wonnarua people, Ashton is alleged to be "causing harm" to the Aboriginal site without an Aboriginal Heritage Impact Permit and in breach of the National Parks and Wildlife Act.

The Office of Environment and Heritage confirmed it had launched an investigation.

The summons was lodged the same day Ashton was in court over attempts to obtain an Aboriginal Heritage Impact Permit over part of the Camberwell site. In December last year Ashton received consent for a modification of its 2002 consent to mine in the area.

It applied to the then Department of Environment for the permit in late January, and on April 21 appealed to the Land and Environment Court against a deemed refusal by the department.

The Office of Environment and Heritage asked the court to refuse Ashton's appeal. The department told the court later there was a prospect the parties could reach agreement.

The permit action returns to court on August 9 after a Land and Environment Court judge on July 7 upheld an appeal by the Wonnarua people that there had not been sufficient consultation.

A spokesman for Ashton said the company could not comment. The summons matter is in court on Friday.