Work has stopped on tunnels at the trouble-plagued Snowy 2.0 pumped hydro project after workers raised concerns about underground “refuge chambers”.
The portable chambers are a “last resort” for workers trapped underground. They are about the same size as a shipping container and are designed to provide protection for up to 24 hours.
Two tunnel boring machines carrying the chambers have now stopped work after staff raised concerns about them with management.
The $12 billion project aims to link two large dams in a remote stretch of the Kosciuszko National Park and is expected to eventually provide up to 2.2 gigawatts of power to the national grid — enough to power 3 million homes for a week.
One of the stalled machines, named Florence, has been forced to stop tunnelling twice before: once for nearly a year after hitting soft ground, and again for two months after hitting hard ground.
Both Florence and another tunnel boring machine, Lady Eileen Hudson, haven’t moved since early last week.
With both machines not operating, underground work on Snowy 2.0 has largely halted, though a third machine — Kirsten — has continued.
In a statement, Snowy Hydro said it expected work to resume shortly once the concerns of workers are addressed.
“Some underground work at Snowy 2.0 has temporarily stopped while principal contractor Future Generation Joint Venture (FGJV) takes steps to ensure a back-up safety system meets strict safety requirements,” it said.
“Snowy Hydro expects FGJV to maintain the highest safety standards and requires the contractor to resolve matters relating to certification, management plans and additional training requirements, before underground work in these two areas can begin again.”
Latest delay to critical mega project
Snowy 2.0 has faced a long list of issues since work began on the “mega project” in late 2019.
The expected cost has blown from $2 billion to $12 billion since it was initially proposed and the timeline for completion has moved from 2021 to 2028.
Problems with Florence, which is working on the project’s largest “headrace” tunnel, have been a major concern — eventually forcing Snowy to acquire a fourth tunnelling machine last year.
There have been other delays too, including a partial tunnel collapse and a sinkhole opening up.
The project has a tight time frame to meet its deadline of offering its first power in 2027, which is largely dependent on how quickly the tunnels can be built.
The national energy market operator has pointed to delays to Snowy 2.0 as a significant future threat to reliability in the power grid.
Given this delay is due to concerns around safety and training, rather than complex technical problems, Snowy Hydro said it is confident work will resume relatively quickly.
“[The contractor] has advised Snowy Hydro that it expects all work to resume shortly. All surface work on Snowy 2.0, as well as some underground work, is continuing unaffected,” the statement reads.
