Two of HS2's longest tunnels have reached the halfway point of excavation, the rail company has announced. Giant tunnelling machines have been excavating the high-speed rail project's route under the Chilterns in Buckinghamshire for the past 18 months, and are now halfway through the 10-mile tunnel.
The machines have excavated enough chalk and flint to fill more than 500 Olympic swimming pools. Martyn Noak of HS2 Ltd described it as an 'important tunnelling milestone'. The Chiltern tunnel is the longest on the HS2 project, designed to improve links between London, Birmingham and the north of England.
The project has faced criticism about its impact on the land, with campaigners fighting against plans to build on woodland. The two tunnels, between the M25 and South Heath, have five shafts for emergency access and ventilation near Chalfont St Peter, Chalfont St Giles, Amersham, Little Missenden and Chesham Road.
The 1.3 million cubic metres of excavated chalk and flint will be used for a chalk grassland restoration project at the south portal. HS2 Ltd said the project would see the creation of 127 hectares of new landscaping, wildlife habitat and biodiverse chalk grassland.
Mr Noak added: 'This tunnel will take HS2 underneath the Chiltern hills, safeguarding the woodlands and wildlife habits above ground as well as significantly reducing disruption to communities during construction and operation.' However, Penny Gaines, chairwoman of campaign group Stop HS2, previously argued that the project was 'based around saving a few minutes on train journeys, but it's far more environmentally friendly not to travel at all'.
