Testing undertaken at St Thomas Aquinas Primary School identified the presence of PFAS on the school's oval and near playground equipment at levels which exceed national safety guidelines.

PFAS contamination was also identified at the neighbouring Ginninderra Christian Church site.

Government testing has also revealed eight other sites operated by the Emergency Services Agency are contaminated with PFAS at concentrations exceeding the recommended threshold for ecological and human levels.

The school and church sites are next to the former West Belconnen fire station site, which was sold in 2016 and redeveloped into a childcare centre, despite health authorities raising concerns over the plan.

PFAS, which has been linked to chronic diseases, was used in firefighting foam in the ACT until 2005.

Associate Professor Robert Niven, who is based at the University of New South Wales in Canberra, said the grounds of St Thomas Aquinas Primary School should be closed until they can be completely remediated, as PFAS-contaminated soil can be ingested when it is blown in the wind.

"That's actually quite a significant risk of exposure," Professor Niven said.

Ross Fox, the director of Catholic Education in the Archdiocese of Canberra and Goulburn, said St Thomas Aquinas Primary School had secured its own testing in 2019 after a parent raised concern over the school's proximity to the former fire station.

"That testing identified elevated levels and obviously we immediately then engaged with the ACT government and then they took carriage of it, as such. We then fenced the area involved," Mr Fox said.

An area along the school's western boundary, which is next to the old fire station site, has been fenced off. A small area next to a playground and within 20 metres of the school's building has also been fenced off. The area between the fenced off sections remains unsecured.

Mr Fox said it was unclear why the elevated levels had been detected in areas at a significant distance from the old fire station site. The school has acted according to advice from the ACT government and the Chief Health Officer.

"It's unclear exactly how some of the elevated levels have come to be present. But at all times we've had the relevant areas fenced off. And we're working very closely in discussions with the ACT government ... about the best form of remediation," he said.

"Our interest has been at all times to ensure that obviously there's no risk to human health of anyone at the school."

Mr Fox said he hoped remediation work could be completed promptly to restore the school's full amenity.

However, Professor Niven said the whole site should be fenced off until it could be remediated.

"Once these chemicals get into the body, they don't go away. They bind very strongly to proteins. ... We can only act to protect the future, so I think they should act. I think they should do something about that now. And not just think that fencing off a few patches is going to be sufficient," he said.

A post-election briefing to the Minister for Police and Emergency Services Mick Gentleman, released under freedom of information laws, noted the PFAS test findings at the school and church sites.

The briefing said the Justice and Community Safety directorate engaged GHD Pty Ltd in January 2020 to conduct testing at the former West Belconnen fire station, eight current fire stations and the primary school and church sites.

"An independent auditor (Ramboll) has been engaged to review all stages of the former ACTFR West Belconnen site investigation, consistent with [Environment Protection Authority] processes," the briefing said.

Professor Niven said the ACT government should make the testing reports for the school and church sites publicly available and also release the results from the eight other locations.

Other affected sites include the Fyshwick, Gungahlin, Ainslie, Chisholm, Phillip and Kambah fire stations and the former Greenway fire station.

Government testing should be expanded to adjacent sites for all other previously identified PFAS- contaminated locations, to capture potential contamination from run off, Professor Niven, who is establishing an Australian Research Council-funded PFAS testing laboratory, said.

"We've got to learn from experience. The fact that it was missed the first time, OK. It's something we need to get on top of," he said.

An ACT government spokesman previously told the Sunday Canberra Times only "low levels" of contamination were detected on the site and an environmental management plan was in place.

"Required actions have been undertaken at this site," the spokesman said in November 2019.

Per- and poly-fluoroalkyl substances, collectively known as PFAS, were widely used in firefighting foams from the 1970s, and were also used in non-stick cooking surfaces and fabric waterproofing solutions.

READ MORE:

ACT government advice provided to St Thomas Aquinas Primary School said there was no conclusive evidence the group of more than 4000 chemicals caused specific illnesses.

The national Environmental Health Standing Committee recommends minimising exposure to PFAS while further research is completed.

But Professor Niven said there was a strong body of evidence PFAS was responsible for human diseases.

"There's a lot of controversy about this but I consider that that view is incorrect, that there is evidence that PFAS is responsible for cancer, particularly cancer of the kidneys and cancer of the testicles," he said.

The ACT government was contacted for comment on Wednesday, but did not respond to a series of written questions.