Illustration: Matt Golding Potential criminal charges would further expand the fallout from the mine fire, which lasted 45 days and saw vulnerable residents of Morwell advised to leave their homes because of the danger posed by the smoke and ash. The French government-owned company, GDF Suez, is already staring down likely court action over $18 million in costs the Country Fire Authority wants it to pay for the massive firefighting effort to quell the 2014 emergency. In a statement, EPA head Nial Finegan said the investigation was a priority, but the authority would take its time to consider its legal options once the assessment of its evidence was complete. "The EPA recognises the impact the Hazelwood mine fire had on the Latrobe Valley community and local air quality and we are actively pursuing all legal avenues to bring those responsible to account," Mr Finegan said.

It is understood the EPA's latest legal advice is due to be delivered at the end of the month. Under the EPA Act some of the charges open to the authority include: Causing or permitting an environmental hazard

Causing or permitting pollution of the atmosphere

Or, aggravated pollution. These charges carry maximum fines each from about $350,000 to up to $1.5 million, depending on the offence. The mine fire was sparked on February 9 by embers from surrounding bushfires.

The separate advice prepared by the green legal group, Environmental Justice Australia, says the mine fire resulted in the emissions of pollutants including carbon monoxide, particulate matter, nitrogen dioxide, sulphur dioxide and others. During peak times several of these pollutants exceeded standards set out in state environment law. In its advice Environmental Justice Australia points to findings in the first stage of the Hazelwood fire inquiry that GDF Suez's failure to have adequate fire prevention and management plans was a factor in the fire taking hold in the coal and ultimately becoming as bad as it did. In particular the failure to cover and wet open coal, and therefore creating conditions where the fire could take hold, meant it was arguable the mine owners had committed an offence of permitting an environmental hazard, the advice says. The advice was requested by green group Environment Victoria. Its chief executive, Mark Wakeham, said there was a clear case and after 18 months it was time for the EPA to take action over what he described as one of the state's worst pollution events.

"If the Hazelwood fire doesn't lead to a prosecution, there need to be serious questions about whether the EPA has the powers it needs and the powers the community expects," he said. Spokesman for GDF Suez Trevor Rowe said it would be inappropriate to comment with the mine fire inquiry ongoing. State Environment Minister Lisa Neville said: "The EPA should use its powers to ensure we protect our communities."