Ms Safiotti spruiked the project in February, days after being told TBM Grace had been shut down. (ABC News: Marcus Alborn)
Just over a month ago, Premier Mark McGowan and Transport Minister Rita Saffioti donned hard hats and high-visibility clothing to talk up the progress of work on the $1.8 billion train line to Perth Airport and Forrestfield.
“We are very pleased with progress, it is a very exciting project for Western Australia,” Mr McGowan said at the time.
But at no point of that media tour was it mentioned that one of the two boring machines being used to create the tunnel had to be halted earlier that week, even though Ms Saffioti had been told three days earlier.
More than four weeks later, that machine — dubbed Grace — is yet to start up again.
It was first halted due to a pair of “ground disturbances” on Perth Airport land, and investigations into what caused those problems are expected to continue for weeks more.
“At the time Grace was stopped and there were some initial investigations underway,” Ms Saffioti told Parliament on Tuesday.
“It is a significant project and there will be issues along the way.”
The admission from the minister has drawn heightened criticism from the State Opposition, which has attacked the Government for not revealing the issue to the public until details emerged yesterday.
“It goes to the carriage of the most important capital works program underway in this state,” Opposition Leader Mike Nahan said.
The Liberals were also furious that the Government used its Lower House majority to cut-off debate about the issue, a tactic very rarely used in the WA Parliament.
Earlier, Ms Saffioti downplayed the problem with the airport rail line — saying there were always likely to be some issues with constructing tunnels in a part of Perth where that had not occurred before.
“This isn’t significantly delaying the project nor increasing the cost and they’re the two key issues you need to be aware of,” she said.
“The important thing is that it was picked up straight away and that the processes are now being analysed.”
The machine was shut down last month after ground disturbances at the airport. (Supplied: WA Government)
Premier in the dark on tunnel problem
While Grace has drawn to a prolonged halt, officials said it had previously been ahead of schedule and the other tunnel boring machine — Sandy — has continued to operate, dismissing the prospect of delays to the project.
The tunnel is due to be completed in 2020 and will provide an underground link from Bayswater to Forrestfield via the airport, with trains running above ground into the city.
Mr McGowan, who said he was only told of the ground disturbance problem yesterday, insisted the issues were not significant cause for concern.
“What happens in any construction project is there’s sometimes issues and I understand it those issues are being dealt with,” he said.
“I don’t think it’s unusual for there to be issues on construction sites, there’s issues on every single construction site.”
No cause for alarm, engineer says
Engineers Australia WA transport spokesman Brendan Marsh said the range of soils found on the Perth Airport land — gravel, sand and clay — meant ground disturbances were to be expected, particularly at the start of the project.
Grace and the other boring machine were put to work on the project in November. (Supplied: WA Government)
“[Machine operators] will be reviewing their settings, so they’ll be monitoring how easily the machine cuts through the material and what they need to respond with,” Mr Marsh said.
“When they get the settings absolutely refined, that impact [on the surface soil] will reduce and reduce.”
Mr Marsh said the tunnel was being drilled through the ‘Ascot Formation’, a geological structure known for its highly variable soil.
“They’re starting at the very low-risk end of the project, getting familiar with the material,” he said.
“This is what we expect on a project like this.”