Fire and Emergency New Zealand rural regional manager Mike Grant said Fenz was working closely with the property owner, "who had been hugely supportive", but it would be up to the Fenz legal team and national office as to whether charges would be laid.
The fire, which broke out on the afternoon of January 3, took a team of 40 firefighters and eight helicopters with monsoon buckets nearly two days to bring under control.
About 200ha of steep hillside pasture was burnt but no lives, houses or livestock were lost.
Mr Grant said a senior fire investigator was on the scene the morning after the fire started and established it had been started by ashes from an outdoor fireplace which had been discarded on the property.
He said the ashes were put into a steel drum, where they sat for two days before being put on "a clearish gravelly area" close to the property’s boundary with Hillend Station. The property owner saw the area smoking two days after they put the ashes down. After soaking them with a hose and leaving a sprinkler on them all night, they believed the problem was sorted.
"About three days after that the fire took off, but they had mowed their lawns and put some lawn clippings on them as well," he said.
Mr Grant said the legislation regarding the recovery of costs for a fire changed on July 1 last year, when Fenz was formed.
"Whereas in the past the rural and local fire authorities would have sought cost recovery directly from those identified as being responsible for a fire, that law has since changed.
"There is still scope within the new legislation for cost recovery but we have to do that through legal avenues, through the courts, and we haven’t got to that stage.
"The cost of the fire has been estimated at between $500,000 and $600,000 but is expected to go higher.
"Costs are still coming in. It’s only two weeks since the fire and a lot don’t invoice until the next month," he said.
"You could safely assume that 60% to 70% of the costs so far are aircraft costs but in saying that there were a lot of ground crews and costs associated with that," Mr Grant said.
The final report on the Mt Alpha fire is to due to be released within the next fortnight but it is an internal document "and that’s where it will stay at this stage". The ODT went to the property involved yesterday to speak to the owners but no-one answered the door.
Mr Grant said the owners would have been advised by their insurance company not to speak to the media.
He said any damage to neighbouring property would probably be handled by their insurance company as it did not involve Fenz.
