It's 5.30am.
Some 520km southwest of Sydney, at Lockhart in the northern Riverina, the temporary digs are home to him and 200 others helping construct the country's largest energy transmission project.
He generally works two weeks on and a week off.
Mr Mansfield is the logistics superintendent for the 164km stretch of the EnergyConnect high-voltage tower network being completed to link NSW, Victoria and South Australia.
It's a two-and-a-half-hour drive to see his family - far but manageable compared to the distances many of his colleagues have to travel home.
While efforts have been made to improve the experience for fly-in, fly-out workers, such as those living in the camp, Mr Mansfield says it can still take a toll.
Especially for those with longer stints between time off.
"The minimum days that our guys are doing is 10-and-a-half-hour days and that's in rain, hail and shine," he tells AAP.
"It can mentally start to affect people without them realising it."
Mr Mansfield says Elecnor Australia, engaged by transmission network operator Transgrid to do the construction work, has taken steps to improve the quality of life on the camp.
He has been particularly impressed with the on-site gym, with staff proactively approaching workers to encourage them to drop in for a class.
"I didn't realise how just doing a circuit in the gym with a crew would get me meeting different people in different groups," he concedes.
Once complete, EnergyConnect will span 900km.
It's been billed as the kind of infrastructure that will improve grid reliability and security and help underpin the broader energy transition from coal to renewables.
Mr Mansfield's role in the almost-complete mega-project involves ensuring the right materials are in the right place at the right time between Dinawan and Wagga Wagga.
Building happens in stages.
Foundations go in first, then the steel towers.
Finally, conductor wires are strung into place.
Managing logistics across the mammoth undertaking has its challenges, Mr Mansfield says, with his section alone involving 50,000 tonnes of steel for the towers.
"In a span of 160 kilometres. It's hard being in all places at one time," he says.
And like any big project, it hasn't been all smooth sailing.
There have been cost overruns, delays and criticism from the electrical union, which has taken Transgrid to the Federal Court over alleged long-term use of outsourcing without consulting employees.
Mr Mansfield says local communities in his section have been broadly welcoming, with some understandable concerns from farmers, including fears vehicles could bring in weeds and disease.
That's meant hosing down equipment thoroughly before entering some properties.
"You can imagine the size of the machines that we were taking in there, and we had to clean them like they had just come off the showroom floor," he says.
Reflecting on his years spent on the project, Mr Mansfield says he's proud to have played a small part in building the next generation of infrastructure.
"You look up and see these towers and the sheer size of them and you think, 'you know, there was nothing here 18 months ago'."
Back at ground level, it's the little things that can keep workers upbeat, such as the occasional sightings of wildlife.
Snakes are a less welcome sight.
"We've got a fair contingency of New Zealand people, and obviously, New Zealand doesn't have snakes," Mr Mansfield says, suppressing a smile.
"You'd think nothing would scare them but, yeah, they see a snake and they can run very fast."