A letter from Metropolitan Fire Brigade chief executive executive Jim Higgins to staff on October 11, supplied to The Courier, said MFB’s regular testing regime at the facility identified “a low reading of PFOS at the point of delivery (hydrant)”.

“The level returned was equivalent to 40 parts per trillion, which is below both the US EPA and the Interim Commonwealth guidelines published by Enhealth for drinking water. The US EPA standard is 70 parts per trillion,” the letter read.

“On receiving the results and in accordance with our protocol MFB immediately switched over to mains water and stopped using water from VEMTC’s treated water system.”

PFOS was also found at the now closed Fiskville CFA training complex, with the site tested in the past for residues from firefighting foams used until 2007 which contained the dangerous chemical.

PFOS is also found in everyday products such as make-up, shaving cream and paper packaging.

Professional firefighters now trained at the Craigieburn site after the closure of Fiskville.

Ballan volunteer firefighter Ian Ireland said the findings raise questions over the Fiskville closure.

“They condemned Fiskville for PFOS, but here we are with a brand new facility that  has (also) recorded levels of PFOS,” he said.

“It's not good enough.

“And this (Craigieburn) is a place where volunteers can't train at.

“It raises my concerns and a lot of other people's concerns about the real story behind Fiskville in relation to PFOS.

“Release the documents and show the people where the high readings were at Fiskville.”

Mr Higgins’ letter stated that no elevated levels of PFOA (another hazardous chemical) were found on the site, while water rings mains were flushed for cleansing, while mains water was tested as a precaution

A secondary letter from MFB work health and safety director Michael Coffey on Thursday, also supplied to The Courier, said the a second sample of tests results “show a lower reading for trace amounts of PFOS – 30 parts per trillion – than the first test, but validate action taken to address above background levels”.

“MFB switched to mains water at VEMTC upon receipt of the first results and will remain on mains water until satisfied the the treated water process is safe and we have determined the case of the elevated levels,” the letter read.

“Our review is ongoing and will involve further tests of VEMCT’s water processing.”

The Courier sought more information from MFB on the findings, including how PFOS got on the site, when the mains water would be switched back on, if training at the VECMT had been cancelled and what additional measures had been taken to ensure the chemical is removed from the site.

However, an MFB spokesperson declined to comment.

Emergency Management Victoria was also contacted for comment.