A grassfire burning between Wee Jasper and Yass in the New South Wales Southern Tablelands is now under control, but fire crews remain nervous a change in weather conditions could see the blaze jump containment lines.
The fire's status is currently at advice level and there is no threat to homes in the area.
The blaze, which authorities were alerted to on Saturday afternoon, has burnt through more than 2,000 hectares in the Narrangullen area south of Burrinjuck Dam.
About 80 Rural Fire Service (RFS) volunteers from NSW and the ACT, along with two water bombing aircraft, have so far managed to protect homes and sheds, apart from an old uninhabited cottage.
"It had long grass right up to the cottage, it was almost undefendable," NSW RFS Southern Tablelands district manager Peter Alley said.
"We had units there: they tried their best but couldn't save it in the end."
Dozens of sheep have had to be euthanased and rangers are still assessing a herd of cattle that were in the path of the blaze.
Wee Jasper Road remains closed, with smoke visible across the Yass Valley and parts of the ACT.
By lunchtime on Sunday, heavy machinery had been used to contain the fire.
"With all the crews and all the dozers and the graters that we've got here today, we're pretty confident we can hold it in the containment lines," NSW RFS group leader Eric Gruber said.
"But that will depend on the wind that picks up this afternoon or the next day or two.
"We'll be mopping up here probably for a good week with the heavy timber."
He said there was a risk the fire could turn back towards Wee Jasper if an easterly wind picked up.
'Months and months of rebuilding'
The fire rolled through the Cavan West property "very quickly" on Saturday evening, destroying fences, gates and injuring some livestock.
"With the heavy fuel load it was very hard to contain, even with the trucks rolling working in a line with a convoy," Mr Gruber said.
Cavan Station general manager Matt Crozier said they were still assessing the damage across two properties and rounding up livestock.
"We've got fences down and burnt, gates open everywhere," he said.
"Animal welfare is the first priority, we try to get the animals safe and onto food and water.
"There'll be months and months of rebuilding and refencing all our land."
Fire likely started by lightning strike
Superintendent Alley said the fire probably started from a lightning strike on Thursday.
"It was fairly remote to start with and then under the conditions of yesterday it grew quite rapidly," he said.
With the large grass fuel load in the region, Superintendent Alley said he "lost count" of the number of fires his crews managed on Saturday.
Some of the other fires were also started by lightning, but Mr Alley said "just as many" were ignited by angle grinders and welders — despite Saturday's total fire ban.
"They can expect a visit from the police for using those implements on a total fire ban day," he said.
