Documents obtained by the ACF under Freedom of Information revealed the $12,600 fine levied by the Federal Department of Environment and Energy.

Inpex was found to have breached its environmental approval by boiling wastewater containing PFAS chemicals at its Darwin Harbour plant.

The department's internal advice states the offence "may have placed the immediate environment including Darwin Harbour at risk of heightened PFAS levels", the ACF said.

The department fined Inpex in April.

In a statement yesterday, an Inpex spokeswoman said: "Inpex considers this process was done in accordance with all approvals but nevertheless made the requested payment when a notice was subsequently received".

"It is not clear whether the community was notified of the offence beyond a brief reference to the infringement on the department's website," according to the ACF.

"Inpex has been caught releasing highly toxic chemicals into the Darwin Harbour environment, which is home to threatened wildlife, yet the fine it has received is nothing but a slap on the wrist," Environment Centre NT director Shar Molloy said.

"Darwin Harbour is home to protected marine animals such as dugongs, rare sawfish, sea turtles and several types of dolphin, along with dozens of native bird species."

PFAS is potentially toxic to human health and is the subject of continuing court cases in Australia and the USA.

The historical release of PFAS from Defence Force bases and airports has raised concern in communities, including Katherine in the NT, where residents have been found with high levels of the substance and restrictions have been put on eating fish and crustaceans from local rivers.

"The impact of PFAS on the environment is not fully understood, but recent research for the Defence Department finds exposure poses a risk to ecosystems," Ms Molloy said.

"That the only public notification of this incident seems to be a one line statement from the Federal Department of the Environment, shows how deficient the Northern Territory's environmental laws are.

"The NT Government and companies like Inpex that profit from operating here owe it to the NT community to protect us and the environment we love and rely on from toxic industrial pollution."

Protect Country Alliance spokesman Graeme Sawyer said: "This Inpex incident further demonstrates the gas industry cannot be trusted. They have no decent plan for their dangerous waste byproducts.

"They have no respect for Territorians or our environment and will do what ever it takes to save a few dollars. This corporate greed has to change.

"The small fine imposed here will not make any difference to big corporations choosing to put human health and our waterways at risk."

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