Residents of Wagga Wagga and Richmond in NSW, Wodonga in Victoria, Darwin in the Northern Territory and Townsville in Queensland, Edinburgh in South Australia and Bullsbrook in Western Australia allege their land and water supplies have been contaminated by PFAS chemicals used in military bases.

Law firm Shine Lawyers said it will file the class action, which seeks compensation for residents who have experienced significant drops in property prices, in the Federal Court in NSW on Thursday.

Shine Lawyers' Special Counsel Joshua Aylward argues every aspect of the residents' lives has been impacted by the contamination and in some cases land values have decreased by more than 50 per cent.

"These toxins are permeating the environment around them, with high levels found in rivers and creeks, livestock, crops, drinking water, and in people's blood," he said in a statement.

"Property prices are plummeting as a result of this contamination."

Mr Aylward claims the residents were exposed to PFAS as a result of the government's negligence and the class action is holding them to account for failing residents.

Residents affected by the contamination are automatically involved in the action unless they choose to opt out at a later date.

Lead applicant Reannan Haswell says she moved to Bullsbrook, northeast of Perth, 10 years ago with her partner Beaux Tilley.

They now hold serious concerns about their family's safety.

Mr Tilley says they're afraid to let their children drink or bathe from their water supply.

"We're trapped on property with little or no value as a result of our exposure to PFAS," he said in a statement.

Shine Lawyers in February this year reached an in-principle agreement with the Department of Defence over PFAS contamination which impacted residents in Oakey in Queensland and Katherine in the Northern Territory.

Australian Associated Press