For the tunnel section (extra ordinary) "wear to the cutting equipment on the tunnel boring machines" due to the abrasive nature of the granite in the geology is mentioned.

Last Civil Contract for Cross Island Line Phase 1 Awarded

The Land Transport Authority (LTA) has awarded the civil contract for the design and construction of Bright Hill interchange station and tunnels under Cross Island Line Phase 1 (CRL1) to Penta Ocean Construction Co., Ltd. at a contract sum of around $526 million. With the award of this contract, LTA has appointed contractors for all 12 stations for CRL1.  

2.      Penta Ocean has a strong track record of undertaking infrastructure, building and tunnelling projects in Singapore. The company previously worked on Bright Hill station along the Thomson – East Coast Line (TEL). They are currently constructing the station, tunnels as well as the Customs, Immigration and Quarantine Building for the Johor Bahru – Singapore Rapid Transit System Link as well as the tunnel between Suffolk Walk and Novena Rise for the North-South Corridor.

3.      Construction works for CRL1 Bright Hill station are expected to start in the second quarter of 2022, with passenger service expected to commence in 2030. When completed, commuters can conveniently transfer between CRL and TEL using this interchange station.

Engineering Highlights

4.      Bright Hill station is located along Sin Ming Avenue where the ground is made up of predominantly Bukit Timah Granite. Due to the abrasive nature of such ground conditions which is expected to cause some wear to the cutting equipment on the tunnel boring machines, close monitoring will be carried out to ensure optimal equipment performance.

5.      The new station will also be connected to a new Transit Priority Corridor (TPC) along Sin Ming Avenue to give commuters more accessibility options via bus and active mobility travel modes. When the TPC is fully completed in 2029, residents in Sin Ming area will have more access options to Bright Hill MRT station and recreational spaces such as Bishan-Ang Mo Kio Park. Educational institutions such as Ai Tong School and Eunoia Junior College will also be within convenient reach by public transport and active mobility modes.

About the CRL

6.      The CRL is Singapore’s eighth MRT line. It will serve existing and future developments in the eastern, north-eastern and western corridors, linking major hubs such as Jurong Lake District, Punggol Digital District and Changi region. The CRL will have almost half of its stations as interchanges with other rail lines, making it easier and more convenient for commuters to travel across the rail network.

7.      CRL1 is 29 kilometres long and comprises 12 stations from Aviation Park to Bright Hill^[1]. This will serve residential and industrial areas in Loyang, Tampines, Pasir Ris, Defu, Hougang, Serangoon North and Ang Mo Kio and benefit more than 100,000 households. With CRL1, common recreational spaces such as Changi Beach Park and Bishan-Ang Mo Kio Park will be more accessible by public transport. Studies on the details of subsequent CRL phases are ongoing.

https://www.lta.gov.sg/content/ltagov/en/newsroom/2022/3/news-releases/last_civil_contract_for_CRL_phase_1_awarded.html

Singapore Land Transport Authority drawing and release.