The owners of Victoria's Hazelwood coal mine will face accusations of causing air pollution during a mine fire.

The Hazelwood mine fire started in February 2014 and burnt for 45 days, leaving the Latrobe Valley covered in smoke and ash, and leading to the premature deaths of several residents, authorities say.

Victoria's Environment Protection Authority has now placed formal charges on four companies with a stake in the mine: Australian Power Partners B.V., Hazelwood Churchill Pty Ltd, Hazelwood Pacific Pty Ltd and National Power Australia Investments Limited.

The charges allege that the fire created an atmosphere that was:

  • noxious or poisonous or offensive to humans
  • harmful or potentially harmful to the health, welfare, safety or property of humans
  • detrimental to any beneficial use made of the atmosphere

The companies have pleaded not guilty.

A directions hearing has been set down for next month.

Victoria’s Workcover Authority has launched separate prosecutions of a fifth company, Hazelwood Power Corporation, another owner of the Hazelwood power station.

Hazelwood Power Corporation has pleaded not guilty to 10 alleged workplace safety breaches.

French corporation Engie is the parent company of all five entities being prosecuted.

The charges come with maximum fines of $10 million.