Of course these sort of proposals are a dime a dozen, but considering the proposers in this case are a former DfT civil servant and someone involved with HS2 and Sizewell C it seems to be worth taking somewhat seriously.
www.bbc.co.uk
How the Norway method could revive Peak District road tunnel
Experts say "drill and blast" techniques in Norway could be used, slashing the cost to £2bn.
A proposed tunnel linking Manchester and Sheffield through the Peak District could generate billions of pounds in economic benefits and cut journey times by up to 30 minutes, its backers have claimed.
Trans-Pennine Connect, developed by infrastructure group Future Works, would see a 14-mile (22km) dual carriageway built beneath the Derbyshire national park.
The scheme does not yet have government backing, but its promoters said it would remove traffic from some of the park's most environmentally sensitive areas and allow sections of the existing route to be restored to nature.
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The project would also involve moving existing electricity infrastructure, which campaigners have said could clear the way for the restoration of the Woodhead rail route between Manchester and Sheffield.
The idea of a tunnel has been considered before, but concerns over cost have prevented it from progressing.
The project's backers said it could be funded without direct support from Westminster.
Future Works said a previous government assessment estimated a tunnel could cost £10.6bn using conventional UK construction methods, including large tunnel-boring machines.
The group is instead proposing the use of a "drill and blast" tunnelling technique commonly used in Norway.
Supporters of the approach said it relied on smaller specialist teams and the natural strength of the surrounding rock, reducing costs significantly.
The organisation estimates that, based on Scandinavian construction costs, the tunnel could be built for less than £2bn, with savings helping to fund the reinstatement of the Woodhead railway.
They said the tunnel costs could be recouped through tolls over time.