The Circle Line Stage 4 C855 project is a design and build project which STECS undertook in the name of a joint venture with Woh Hup and Alpine Mayreder. This project includes construction of Holland Village Station, Buona Vista, Kent Ridge and One North Station, 8.25km TBM tunnels and 0.35km C&C tunnel. Two 6.35m diameter EPB machines and two 6.35m diameter slurry machines were used to construct the bored tunnels. The contract value is S$399.91 million.