The Commonwealth has not admitted liability in the suit, which accused Defence of failing to adequately prevent PFAS from entering soil and groundwater.

In a press conference, Prime Minister Anthony Albanese said that the case pre-dates the election of his government but acknowledged the problems with the “forever chemicals”, which accumulate in the body without naturally degrading.

“PFAS has been an issue, and its use, around many communities, particularly those around airports,” he said.

“People have, across a range of communities, suffered from the use of this. It’s another example of where we have to get occupational health and safety right.

“We need to get it right in the first place — that would avoid these sort of actions. The biggest concern that I have with PFAS isn’t, of course, a financial one — it is the health outcomes of people who are affected by it.”

In a statement, Craig Allsopp, joint head of class actions at Shine Lawyers — which has been representing the plaintiffs — said the settlement would head off the possibility of a high-risk trial.

“The settlement money, if approved, will go some way to compensate the seven communities in this class action for their losses; however, many are still stuck on contaminated land,” he said.

A federal parliamentary committee in 2018 called for a ban on the use of PFAS in aviation firefighting on military bases, and the establishment of a coordinator-general to manage the fallout from their use.

The recommendations were two of nine included in the report by a joint standing committee on foreign affairs, defence and trade inquiry into the management of per- and poly-fluoroalkyl substances (PFAS) contamination in and around Australian Defence Force (ADF) bases.

“The committee has recommended that a coordinator-general be appointed with the authority and resources necessary to more effectively coordinate the whole of Commonwealth government effort in respect of PFAS contamination and to ensure a clear and consistent approach to community consultations and to cooperation with state, territory and local governments,” said the foreword to the report.

PFAS are man-made chemicals that have been commonly used in firefighting foams. The best-known examples of PFAS are perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonate (PFHxS). They have been linked to adverse health outcomes such as birth defects and cancer.