By lyndamyer
Due to a surface depression in Snowy 2.0 project, a TBM has been stopped but Australia’s Snowy Hydro says that the solid construction progress is being made.
TBM Florence, which is excavating the headrace tunnel at Tantangara, was transitioned from soft material into harder rock conditions in December 2022 and a depression developed on the surface above the machine. However, as Snowy Hydro stated the integrity of the tunnel had not been compromised, and tunneling was advancing while work to remediate the surface depression was carried out with applying a safety exclusion zone around the surface depression.
While plans to remediate a surface depression above the Tantangara adit are concluded, in reaction to a report by the Australian Broadcasting Corporation, a statement on Snowy Hydro’s website says the TBM is temporarily halted.
According the statement: “Across the project, and as anticipated, the ground conditions encountered by the Snowy 2.0 TBMs are highly variable, ranging from soft, sandy ground to extremely hard rock. Complex and variable ground conditions are not unusual in such projects. Snowy Hydro and the Snowy 2.0 EPC contractor, Future Generation Joint Venture, are focused on delivering the project safely and in a manner respectful of the sensitive environment, while managing impacts caused by external events including Covid-19, high material costs, global supply chain constraints, labour shortages across the Australian construction industry and ongoing weather conditions.”
“Commercial claims on construction projects are also common. As with other major infrastructure projects, Future Generation Joint Venture has experienced significant impacts from Covid resourcing and supply chain challenges. Claims submitted to Snowy Hydro by the contractor continue to be assessed and paid appropriately, in accordance with contractual requirements,” added in the statement.
Snowy Hydro says: “Solid construction progress is occurring across a large number of Snowy 2.0 work fronts. At Lobs Hole, the Talbingo intake is well under way, the main access tunnel excavation by TBM Lady Eileen Hudson is completed and the emergency, cable and ventilation tunnel excavation by TBM Kirsten is close to completion.”
Meanwhile, the determined budget for the Snowy 2.0 with A$5.9bn (US$4bn) value has remained unchanged since the project approval.
Connecting Tantangara Reservoir (top storage) with Talbingo Reservoir (bottom storage) through 27km of tunnels and a power station with pumping capabilities, Snowy 2.0 is Australia’s largest renewable energy project.
The advantages of advancing this project will be enabling water to be released for energy generation at times of peak demand and pumped back to the top storage when there is excess renewable energy in the system, ready to generate again.
