The Commonwealth agreed to pay $22 million to people living in Wreck Bay, on the NSW south coast, after the toxic foam used at nearby defence sites leaked into sacred waterways.
The settlement of the civil action, brought by the Wreck Bay Aboriginal Community Council, was approved by the Federal Court in 2023.
Members of the Wreck Bay Indigenous community on Tuesday told a federal inquiry of their continued concerns about contracting cancers and their inability to fish and swim in their waterways.
Shine Lawyers' Craig Allsopp, who worked on the case, said there was anecdotal evidence that defence staff made "snow" fields out of the firefighting foam during Christmas celebrations.
Without realising the toxicity of the foam, workers also sprayed the foam to farewell colleagues.
"They just had no idea," Mr Allsopp told the inquiry sitting in Nowra.
"I don't think there's any doubt that this land is contaminated."
The inquiry is examining the social, economic and environmental effects of PFAS (per- and polyfluoroalkyl substances), including sources of exposure and the adequacy of regulations.
PFAS chemicals are known for their heat, water and stain resistance and have been commercially produced for decades for use in firefighting foam, aviation, carpets, cookware, fabric and cosmetics.
PFAS was once used in firefighting and the chemicals have been detected near defence bases and airports around Australia.
The defence department has remediated 28 sites since 2015, including two near Wreck Bay, where 21 million litres of water has been treated to limit further contamination.
"We remove PFAS from the water, which is the way we will limit its capacity to continue moving off base and through both groundwater and surface water into communities," acting associate secretary Celia Perkins said.
David Goldberg, who worked as a GP in Wreck Bay from 2000 to 2008, said he suspected the community was subject to a cancer cluster likely due to PFAS exposure.
Two patients from one family died before the age of 50, one from breast cancer and the other from bowel cancer.
"I'm aware that many people are dying, that most of them it's from cancer," Dr Goldberg said.
Dr Goldberg said it was statistically impossible to prove cancer clusters due to small sample sizes, but there was international evidence that PFAS was a likely carcinogen.
While it was highly likely PFAS was having health effects, there was no doubt the contamination had diminished the cultural practices of the Indigenous community, he said.
They were unable to swim, fish or grow vegetables in order to reduce potential harms.
"What price do you put on that for a non-stick frying pan?" Dr Goldberg said.
"I don't think it's worth it."