A new heritage report on Ravensworth Estate and its surrounds has reinforced the area's cultural significance to the Upper Hunter's indigenous community.
The NSW Department of Planning commissioned the report as part of its assessment of Glencore's proposed extension of the Glendell coal mine.
The existing mine, which employs about 300 people, is approved to continue operating until 2024.
The Continued Operations Project would extend the mine's life until approximately 2044 and result in the extraction of an additional 140 million tonnes of coal.
The new report by Hector Abrahams Architects found the Ravensworth Estate, which is located within the footprint of the proposed mine extension, was "likely ... to meet the threshold for state heritage significance for its historical heritage value".
It also found that mining in the area would violate the traditional relationship between the Aboriginal peoples and their land.
The claim is supported by Colonial records that show a series of attacks and counter-attacks between Aboriginals and settlers occurred at the Ravensworth Estate and the adjoining Lethbridge Estate between 1825 and 1826.
But historians are divided on the exact location of the massacre. Glencore disputes that a massacre occurred on the site of the proposed mine extension.
Regardless, the new report acknowledges the significance of the series of violent events to the local Aboriginal and wider community.
For Wonnarua people particularly, the review notes that "there is social value attached to this specific bounded place of the Ravensworth Estate for at least some Wonnarua people."
Plains Clan of the Wonnarua People spokesman Scott Franks said the report confirmed the area's spiritual and social significance to Aboriginal people.
"We have lost a lot of Country to coal mines and we do not want this area to suffer the same fate," he said.
"This location contains the remains of our people and the earth is filled with our people's blood, our women, children and warrior's spirits continue to roam those lands known today as the Bowman and Lethbridge estates.
"Because the spirits of our people are unsettled, no cultural ceremony has been allowed for our peoples spirits to move to the next place, back to the sky with our protectors."
Surgeon James Bowman established the Ravensworth Estate in 1824.
The homestead comprises four sandstone buildings and a timber cottage.
Dismantling and relocating the homestead buildings is among the options being considered as part of the project.
