Under its Terms of Reference, the Board of Inquiry must report on the origin and circumstances of the Hazelwood mine fire, including how it spread into the mine.

The Hazelwood mine fire started as a series of smaller fires that ignited in the northern, eastern and south-eastern batters of the mine on 9 February 2014. For the purposes of this report, the Board refers to all fires within the mine as the ‘Hazelwood mine fire’ or ‘mine fire’.

In order to ascertain the origin and circumstances of the mine fire, the Board has considered Victoria’s particular vulnerability to fire, the fire activity in the vicinity of the mine in the days leading up to the mine fire, and witness observations at the time the mine fire ignited and spread.

Victoria is one of the most fire prone areas in the world. Victoria is at risk of bushfire every summer. Leading up to and during 9 February 2014, Victorians were given explicit warning that they were to prepare for potentially catastrophic fire conditions.

On 7 February 2014, the Hernes Oak–McDonald’s Track fire started approximately five kilometres to the north-west of Morwell. At approximately 1.15 pm on 9 February 2014, the fire broke containment lines and became known as the Hernes Oak fire. At approximately 1.40 pm on 9 February 2014, several fires ignited near Driffield. Those fires quickly joined to form one fire front. This fire is referred to as the Driffield fire.

The Hernes Oak and Driffield fires were burning in close proximity to the Hazelwood mine. Embers were first seen spotting into the mine just prior to 2 pm on 9 February 2014. At around 2 pm, GDF Suez mine personnel observed the first fire in the Hazelwood mine. The fire quickly spread and was well established in the Hazelwood mine by early evening on 9 February 2014.

The Board accepts the evidence of GDF Suez personnel who saw embers in the air over the mine in the afternoon of 9 February 2014. The Board also accepts the evidence of the Fire Services Commissioner regarding embers spotting into the mine. This evidence was supported by Mr Jaymie Norris, Acting Manager of the Strategic Bushfire Risk Assessment Unit at the Department of Environment and Primary Industries. Mr Norris produced a simulation of the likely fire behaviour on 9 February 2014 based on the conditions of that day. Independent expert Mr Roderic Incoll, Bushfire Risk Consultant, further supports the evidence of GDF Suez personnel and Mr Norris about the likely fire behaviour on the day, having regard to the weather conditions.

The Board concludes that spotting from other fires was the most likely cause of the Hazelwood mine fire. Based on the information before it, the Board concludes that the fire did not start within the mine, either from a hot spot or from the operating area.

It is difficult to determine with precision which of the one or more external fires was responsible for the spotting of embers into the Hazelwood mine. On the evidence provided, the Board concludes that spotting from the Hernes Oak fire was the more likely cause of the Hazelwood mine fire, while spotting from the Driffield fire may have also contributed.

Victoria Police consider the cause of both the Hernes Oak-McDonald’s Track fire and Driffield fire to be suspicious and are investigating both fires.

The Board’s Terms of Reference expressly provide that the Inquiry not prejudice any investigation into the fire by Victoria Police, and that the Board work cooperatively with other investigations to avoid unnecessary duplication. Based on the evidence of Detective Inspector Michael Roberts, Victoria Police, the Board accepts that investigation of the causes of the Hernes Oak-McDonald’s Track and Driffield fires is properly the province of Victoria Police.