A former instructor at the CFA Fiskville training ground says he has proof they knew about contaminated water and made it worse by trying to fix it.
Firefighting recruits were put in danger when the Country Fire Authority added bacteria to try to clean up contaminated water at a training centre, a former instructor says.
Mick Tisbury, a Metropolitan Fire Brigade firefighter for 26 years, says the CFA was aware of contamination in the dams as early as 1988 and failed to act, except by adding bacteria Pseudomonas Aeruginosa to try and remove poisonous hydrocarbons from the water.
But he says that plan backfired, causing numerous health problems for trainee firefighters including skin, lung, eye and ear infections, blood poisoning and urinary tract infections.
"As an instructor, I am very concerned that I unknowingly subjected recruits and firefighters to training in contaminated water," Mr Tisbury told a Victorian parliamentary inquiry into the closure of the site.
One of those recruits could have been Trevor Lansdown, who visited Fiskville many times during the 1980s and says he's still suffering from symptoms linked to contaminated water.
In a submission to the inquiry, Mr Lansdown says he was diagnosed with Merkel Cell Carcinoma, a rare skin cancer usually found in pale women over 50 years of age in the 1990s.
He again became unwell when he returned to Fiskville in 2002, this time with severe stomach pains.
Top ranking CFA officials have previously said they had no knowledge of claims the water was contaminated, and deny they failed to act.
Numerous independent reports dating back to 1988 show the water was unsafe, including five in 1996 that all said urgent action was required.
A report in February 2007 by Ecowise, now known as ALS, said levels of Pseudomonas Aeruginosa in dam one were off the charts, recording 33,000 organisms per 100 millilitres.
The safe level is less than 10 organisms per 100ml.
"The presence of Pseudomonas Aeruginosa at these levels indicates the water is unsuitable for primary contact," the report said.
This was the first time levels of the bacteria were tested at the dam, Mr Tisbury says, and training continued despite the risks to recruits.
"If you bugger up, tell your people," Mr Tisbury said.
Michael Whelan, a former firefighter and union rep, said a worker told him in 1992 chemicals at Fiskville had made him ill.
"I repeatedly and forcefully told the CFA senior management specifically the deputy chairman, chief officer and industrial officer that this had occurred," he said.
Mr Whelan said the matter went nowhere.
The MFB ceased training at Fiskville in October 2012, but CFA recruits continued to train there until it was shut down in March 2015.
Monday was the last day of the hearings and the committee will provide an interim report in the last sitting week of parliament.