Koppers Australia’s Mayfield plant in Newcastle has recorded a naphthalene spill.
According to the EPA the minor incident occurred after pipe was blocked during maintenance and cleaning, the Newcastle Herald reported.
Newcastle plant consists of two continuous tar distillation units and a naphthalene still.
The incident comes as the NSW Office of Environment and Heritage, of which the EPA is part, announces a change to environmental legislation in the state.
It called on the public to submit comments to the proposed changes to improve the way environmental incidents are reported and managed.
Gary Whytecross, the OEH’s acting chief environmental regulator, said the change will see industries in the state required to identify who should be notified and when in the event of an incident.
"The proposed changes put an onus on any industry in NSW who holds an Environment Protection Licence to prepare, implement and test pollution incident management plans," Whytecross said.
"These plans will need to include proposed actions to be taken to protect communities and the environment from a pollution incident and clearly specify the procedures to inform local communities and relevant authorities.
"It’s about ensuring that serious pollution incidents are avoided to every the extent possible, but if they do occur they can be handled quickly and effectively."
The ongoing spills at Orica prompted the change in legislation.