The management of a Victorian coal mine insists it did what it could to reduce the risks of an "unprecedented" bushfire, which sparked a blaze that burned for weeks.
The operator of the Latrobe Valley's Hazelwood Power Station is on trial over the fire, which started inside a worked-out coal mine on February 9, 2014 and burned for 45 days.
"It (Hazelwood Power Corporation) was and is a good corporate citizen caught by circumstances which... at the very least were rare and unprecedented," the company's barrister Ian Hill QC told the jury in his closing address on Thursday.
He urged jurors not to look at the case with hindsight but rather consider whether the company was aware of the risk or ought to have known of the risk of the fire.
Two bushfire fronts impacted the mine and one of those fires appeared to have been started by arsonists, Mr Hill told the jury.
"They are difficult to prepare and plan for," he said and added that employees at the mine faced "war-like conditions" during the blaze.
"It's easy to be wise in hindsight, but not so easy... for the experts to propose suitable and available ways of eliminating or reducing the risk."
The employer followed the legislative requirements, he said.
But prosecutor Sally Flynn QC argued the fire risk from bushfires was well known and should have been taken into consideration.
"Coal mining is an undertaking that has several obvious hazards and risks. Most obvious is the risk of fire," Ms Flynn said on Wednesday.
She said the risk of fire at the site was ever-present and Hazelwood Power Corporation failed to properly take this into account and did not take reasonable practicable measures to prevent them.
The case was not about the outcome but the risk of fire and whether the company put in reasonably practicable measures to limit risk, she said.
"Just because something hasn't yet occurred it doesn't mean you don't have to plan for it," the prosecutor said.
Smoke from the blaze also affected people in the town of Morwell and one woman lost her voice and attributed it to the mine fire.
The company is charged with breaches including failing to do an adequate risk assessment, failing to install alternative power and failing to have a reticulated water pipe system for worked-out mines.
The closing arguments in front of Justice Andrew Keogh will continue into Friday.