New South Wales government has awarded AUD1.8 billion (US$1.3 billion) new twin metro rail tunnels contract for Western Sydney Airport metro line to CPB contractors and Ghella. The scope involves the development of 9.8 kilometers of twin metro rail tunnels in two sections.

The Station Boxes and Tunnelling contract includes:

• 9.8 kilometers of twin rail tunnels in two sections. The 4.3-kilometer northern tunnels run from St Marys to Orchard Hills and the 5.5-kilometer southern section of tunnels runs between the Airport Business Park and the Aerotropolis Station;
• Excavation and civil works for new stations at St Marys, Orchard Hills, Western Sydney International (Nancy-Bird Walton) Airport, and Aerotropolis;
• Four hard rock Tunnel Boring Machines (TBM);
• Building one of the two temporary precast concrete factories for the project on the Western Sydney International site;
• More than 67,000 concrete segments to line the twin tunnels;
• Two TBM launch sites at Orchard Hills and Western Sydney International and two TBM retrieval sites at St Marys and Aerotropolis Station

The tunneling works are expected to be finished in late 2024 after which track laying and fit-out work for stations will be carried out.