University of Melbourne chemical engineering lecturer Gabriel Da Silva said the Campbellfield fire posed two major chemical exposure risks.
One was to first responders and factory workers exposed to the fumes. The other was the run-off from the fire – and the chemicals used to contain it – entering local waterways.
«We don’t know what the bulk chemicals were yet, possibly methyl ethyl ketone and acetone and things like that,» Dr Da Silva said
«Then also waste levels of other compounds of varying toxicity.»
Chemicals contained in firefighting foam deoxygenates water, which can be fatal for insects, fish and other aquatic species.
Dead fish were among the marine life which washed up on the banks of Stony Creek following a toxic chemicals blaze in a Footscray warehouse last year.
Run-off from Friday’s fire flowed into Merlynston Creek. And while authorities claim to have contained the run-off within that creek, the potential to contaminate waterways throughout the city was real.
The Merlynston is a tributary of the Merri Creek, which flows through Melbourne’s northern suburbs before meeting the Yarra.
Once highly-degraded, volunteers and professionals have painstakingly restored habitat along the Merri Creek for decades.
Merri Creek Management Committee’s Michael Longmore said those efforts appeared to have paid off around 2010 when platypuses were spotted in the creek around Coburg. They had been seen most years since and are «really vulnerable to changes in water quality».
The Merlynston meets the Merri in Coburg North.
The Merri may have dodged a bullet this time, with Melbourne Water claiming to have contained the run-off to within a constructed wetland, near the head of the Merlynston Creek.
Melbourne Water said it had people on-site within one hour of the fire. They used sandbags and bunding to prevent the water from flowing downstream.
Pumping trucks took 800,000 litres to a licenced waste disposal facility. A further 5 million litres have since been diverted from runoff through the sewer network for treatment.
Melbourne Water’s Kirsten Shelly said there may have been «a small volume of fire water runoff that passed through to Merlynston Creek early in the event before the containment site was set up, however these volumes would have been minimal.»
On Saturday, the Environment Protection Authority issued a warning for people and pets to avoid contact with the water from those wetlands downstream to the Jack Roper Reserve.
But Mr Longmore said – had the fire broken out «just a few blocks to the east» and flowed directly into the Merri – it could have been an environmental disaster on a much larger scale.
«Ecosystems in and around the Merri Creek are extremely fragmented and [are still] really struggling,» he said.
«Species like the [endangered] growling grass frog are in such a vulnerable state already, things like this could push them over the edge.»
Dr Da Silva warned more chemical fires were inevitable unless drastic regulatory changes were enforced.
«The way we’ve been dealing with [chemical waste is by] sticking it in barrels in urban fringe factories and leaving it there until, god knows what happens to it,» he said.
«Unless something changes, we should expect more of this.»
Dr Da Silva said there should be a register of stored chemicals. Also chemicals should ideally be recycled or disposed of – saying incineration was a better option than uncontrolled blazes.
He backed Mr Longmore’s call for a beefed-up EPA to crack down on improper waste storage to prevent more fires.
«Australia is a big country, we don’t need to store [these chemicals] in urban areas,» he said.
Joe Hinchliffe reports breaking news for The Age.