The preferred contractor for the original Scott Base redevelopment will not participate in the tender for the scaled-down project, announced last year, and will instead focus on NZ-based social infrastructure projects. That is according to Anthony Leighs, chair of Leighs Construction, who has a 20-year-plus history of building in Antarctica: “Up until this point, we are the first and only builder to build for the New Zealand Government in Antarctica,” he told BusinessDesk today.
The new design, which uses a small modular construction methodology and conventional on-site framing rather than the original larger-scale modular construction methodology, comes after cost blowouts and safety concerns led the New Zealand Government to appoint an Independent Review Panel (IRP) to examine a range of scenarios to extend the life of the Antarctic base.
“The new plan means Antarctica New Zealand will not proceed with the proposed three-building design using a large module construction methodology. Transport of the modules carries too great a risk, and the need for fewer new buildings made it less viable,” according to the panel led by Bob Hall, Waren Warfield, Peter Leslie and Adam Feeley. However, the new plan will not start from scratch, according to Sarah Williamson, Antarctica New Zealand’s CEO who said “a lot of the design work (will be) translated from large to small module construction.”
“This is a project like no other”
With a goal “to turn the key by the 2028/29 season,” Antarctica New Zealand will appoint a new contractor for the works next month:
“Early contractor engagement… is critical as it offers a more cost-efficient design; improved cost certainty; opportunity to accelerate project delivery; and enables better identification and allocation of risk,” said Leon Grice, Antarctica New Zealand’s board chair. “The RFP seeks proposals for a main contractor that can provide invaluable input to critical elements such as logistics and construction in remote and hostile environments and designing cost-effective modular buildings.”
“In terms of timing and logistics, this is a project like no other,” according to Jamie Lester, technical principal, building structures at WSP, who spoke about the redevelopment in 2022. Speaking about the previous design, Lester said the building in Antarctica has its challenges:
“It’s a very short construction season with only a four-month window between November and February, when there is enough daylight and it is not so cold….The sea isn’t navigable until January – all of the materials for the following year have to be delivered then, so building can start promptly the next summer.”
And then there are the structural foundations, which, thanks to permafrost, can freeze and thaw. Speaking to the Engineering Matters podcast, Lester said that a range of options were considered, including building on concrete pads anchored to the permafrost, a method for ground refrigeration used a lot in Canada: “Ice is quite elastic, and therefore very difficult to excavate with a machine. It will have to be done using drill and blast techniques, which is very labour-intensive.”
There’s also the problem of working in the coldest climate on Earth: “When I was there in November (2021), it was 5˚C, but felt more like 19˚C with the wind chill,” he said. “The atmosphere is also extremely dry, which affects our choice of materials for the project. In particular, shrinkage of timber is a big problem, so any wood used must be specially treated.”
The changing face of Scott Base and other bases in Antarctica…
According to Elise Grange of the University of Canterbury, the original Scott Base (built in 1957) was constructed from timber parts prefabricated and shipped to Antarctica from Melbourne, Australia – used in the framing, cladding and window frames: “At the Scott Base between 1957 to 1999 Oregon rafts on Jarrah sleepers were used, (but) this has since changed to Pinus Radiata jackstuds and bearers set in 1.5 metres into the ground using ‘Antarctic concrete’ – this does not incorporate cement but uses gravel, water and steel reinforcing rods.”
Despite engineers replacing much of the timber used in cladding, framing, and linings with alternative materials, the majority of buildings in Antarctica now stand on timber poles (and not steel stilts) to allow for snowdrift: “Timber meant that due to the contour of the land, the foundations could be easily adjusted and, therefore, save time.”
