Col Maybury, a member of Hydro’s community reference panel, said he was concerned about the company’s plan to store about 80,000 tonnes of spent pot linings in specially engineered holding cells at the site.

Spent pot lining is the lining from pots used in aluminium smelting.

They can leach fluoride and cyanide, which are toxic.

Hydro management has told the Mercury repeatedly that the company would ensure the linings were safely stored and would monitor the special cells in perpetuity.

But Mr Maybury said acid waste from coal mines could be used to neutralise the dangerous chemicals in the spent pot linings and make them safer to store.

He said he was concerned that leaching from the pot linings could eat through the storage cell walls over several years and contaminate land and water ways from Kurri Kurri to Maitland.

“We’ve put up a simple procedure that’s very cheap to treat the spent pot lining with old coal mining acid, which is a scourge,” Mr Maybury said.

“It neutralises it and makes it far safer to then keep in the ground.”

Hydro Aluminium Kurri Kurri managing director Richard Brown said the company had been working closely with the Environmental Protection Authority to prepare remediation plans for the site.

The company wants to remediate the smelter site and turn it into residential and commercial land in the coming years.

He said the Department of Planning and Environment would place an environmental impact statement on public exhibition mid-year.

Mr Brown said the company would also prepare a submission that would ask Cessnock City Council to rezone the land.

“The overall project has now been renamed ReGrowth Kurri Kurri, to focus on the future potential of the site,” he said. 

“The overall project proposal includes business and industrial development on and near the current smelter site, residential development between Loxford and Gillieston Heights, to the west of Cessnock road, and the conservation of around 1300 hectares of the 2000ha site.”