ANTI-HS2 campaigners have today (Apr 25) launched their case for 'Going Underground' to preserve and protect the Chilterns Area of Outstanding Natural Beauty.

The campaigners say a new study launched today proves the viability of a 24.7km tunnel, which would preserve the protected Chilterns AONB.

The study, produced by Peter Brett Associates, has been commissioned by Chiltern District Council, in association with Aylesbury Vale District Council, Buckinghamshire County Council and the Chilterns Conservation Board.

It proposes a revised Green Route, all in tunnel, which goes under the River Misbourne at Chalfont St Giles as far as the A404.

The route then follows a line east of Little Kingshill and west of Little Missenden to cross under the River Misbourne, Chiltern Line and A413. It then runs parallel to the A413 passing to the east of Great Missenden with an intervention gap close to the A413 south of Bowood Lane.

This is close to existing transport routes, lessening the effect of this open section. Access to the required gap for emergency purposes is accessible from the A413 and will be entirely underground.

The government's current proposed route takes HS2 through the widest part of the Chilterns AONB, which the report states will 'militate rather than mitigate the impact'.

Benefits of this new proposed Green Route include:

- Significantly less impact on the environment and communities in the Chilterns AONB

- The route offers better operational alignment and passes through better and more consistent ground conditions below the water table

- With a gradient of less than one per cent, energy requirements and wear on the tracks would be reduced. The government's current proposed route has a gradient of three per cent

- The Green Route avoids Bacombe Hill, near Wendover, which is the area of greatest slope instability

- Logistically, tunnelling could start at both ends of the tunnel with worksites located at either end minimising disruption to exiting transport infrastructure

- Chalk slurry from boring can be transported long distances by pipeline before treatment and reuse, reducing cost and impact of transportation

- Chalk spoil from open excavations could be used as construction fill material

The cost of the Green Route is estimated at £1.85bn, representing 1.5 to two per cent of the overall construction cost of HS2 Phase One. However, this should be viewed with the considerable mitigation of the effects of the route on the Chilterns AONB and would avoid extensive compensation costs, which have not been factored in at this stage.

Permanent and irretrievable loss of environment on the government's current proposed route is rated 'very high' - and as this latest report demonstrates, is avoidable. As the report states, the technology is available, engineering solutions exist.

The question now is whether a small additional financial cost at construction stage, set against savings across the project's whole life, is worth preserving a beautiful and unique part of the countryside.

In a recent poll in Countryfile News, 93 per cent of respondents said HS2 should not be built.

In the recent responses to the Environmental Statement, a continuous tunnel was the most preferred mitigation measure.

Rt Hon Cheryl Gillan, MP for Chesham and Amersham, said: "If HS2 is to go ahead, any government responsible for this project should provide the maximum protection for the AONB through a full tunnel. This special environment is valuable for future generations and should not be destroyed where extra tunnelling could provide a solution to its safeguarding."

Leader of Chiltern District Council Nick Rose said: “HS2 would create a huge and ugly scar through parts of the AONB. Our proposal represents a huge improvement over the existing government proposed scheme and avoids the reckless damage that the rail line would cause.”

Chief Officer at the Chilterns Conservation Board Steve Rodrick said: "The Chilterns AONB is natural heritage and we expect those responsible for designing the HS2 railway to protect this special place. A long bored tunnel is the only acceptable solution."

Leader of Buckinghamshire County Council Martin Tett said: "The Chilterns are a nationally-designated Area of Outstanding Natural Beauty and a treasure for the whole country. Protecting and enhancing them is one of our key responsibilities we owe to future generations."

Leader of Aylesbury Vale District Council Councillor Neil Blake said: "While we accept that investment in our rail infrastructure is required, I don’t feel that the proposed HS2 project is the best use of public money, nor is the cost of damaging irreplaceable natural heritage acceptable. However, if the project is to go forward, I urge the government to consider our alternative tunnel options that help to avoid permanent environmental damage."

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