Weston Aluminium will pay $200,000 towards environmental and community improvement works after an Environment Protection Authority investigation identified offences including a breach of the company's environment protection licence.
The investigation followed a November 2021 fire at the Kurri plant.
It found the company had breached its environment protection licence regarding the storage of waste material. This included pharmaceuticals and other clinical and related wastes. It also stored paints, solvents and clinical and related waste without appropriate labelling and sufficient segregation.
The company also failed to immediately notify relevant authorities following the fire and unlawfully transported and deposited waste at a neighbouring premise, resulting in land pollution. The estimated combined volume of this material is more than 18,800 cubic metres.
"Our investigation uncovered a series of breaches which posed a threat to the environment in Kurri Kurri," EPA acting executive director of operations Steve Orr said.
"Weston Aluminium, under direction from the EPA, has prepared a revised Fire Waste Management Plan, improved their waste storage practices, cleaned up waste at the neighbouring premises and are creating a remediation plan for the site."
"Under the terms of the undertaking, Weston Aluminium will pay $200,000 towards environmental initiatives carried out by Mindaribba Local Aboriginal Land Council, which will support a dedicated funded role to undertake a detailed audit of illegal dumping on conservation lands and introduce strategies to prevent and detect illegal dumping in the Kurri Kurri-Cessnock area."
Western Aluminium has also agreed to pay the EPA's investigation and legal cost of $43,065.
Weston Aluminium managing director Garbis Simonian said the company was remorseful for the offences.
"Of course it would have been better if it hadn't happened but we also accept the incident had an impact on the community," Mr Simonian said.
"We have taken measures so that it doesn't happen again. We have strengthened our security and also educated our staff to eliminate risks so someone can't break in and do what they did."