
Chiltern Tunnel North Portal
Trains will emerge from the Chiltern Tunnel into South Heath cutting which will be 16 metres deep. The portal will be on farmland just north of Frith Hill. The construction compound will be approximately 1.5ha in size and be in place for eight years. Access to the compound will be via a newly constructed temporary haul road. Realignment of one PRoW (Public Right of Way) will be required. Footpath GMI 13 will be closed during construction and then be permanently diverted to the south of the tunnel portal. The former Weights & Measures Gym (previously the Black Horse public house) will be demolished to allow permanent access to the portal from Frith Hill. A series of piles will be installed to support the last section of the tunnel through soft clay.