Dr James Whelan, the researcher and community organiser for a not-for-profit environmental legal practice, will brief Lake Macquarie councillors on Monday night on the remediation of two local power stations and their associated ash dams.
The Environmental Justice Australia representative told the Newcastle Herald he was concerned the council "may not be as active as it could be" in preventing "another Pasminco".
He said he will argue local government representatives need to seek a remediation plan for Eraring and Vales Point before their eventual closure.
"Lake Macquarie city council takes in the whole of the Eraring ash dam and half of Vales Point's," he said.
"They should be at the negotiation table with the state government and operators of those two power stations to ensure adequate bonds are set for the remediation of the power stations."
Dr Whelan presented similar concerns to the council in March last year, recommending the council "urge the NSW Government to hold bonds sufficient for the cost of decommission and rehabilitation" and ensuring the process met "world's best practice".
He said there are currently "no consistent standards" set for rehabilitating ash dams, which cover hundreds of acres of land in the Lake Macquarie LGA.
"The clock is running, if you like, on those power stations," he said.
"The companies have a social contract to the communities where they are operating, and we expect them to honour that."
He will also speak on the issue of lowering pollution emission limits for both power stations at the council meeting. He said a recent review of Eraring and Vales Point's environmental licences resulted in no substantial changes.
At the time, however, the Environment Protection Authority said licence changes recommended as part of a 2018 review would be implemented "progressively throughout this year ".
Dr Whelan will brief Lake Macquarie councillors at 5.30pm before the ordinary council meeting at 6.30pm on Monday, February 25.