On 2015\06\04 15:58, Mizter T wrote:

On 04/06/2015 09:43, Jim Chisholm wrote:
So reports BBC:
http://www.bbc.co.uk/news/uk-england-london-33002819

"Tunnelling work in London has been completed in the £14.8bn Crossrail
scheme.
Eight boring machines have been cutting their way through earth to
create 26 miles (42km) of tunnels."


AFAIAA, there haven't been any tunnelling mishaps, which is perhaps
worthy of note and acclaim.

What would a "tunnelling mishap" be? I remember the NATM problem at
Heathrow, but that was surely a rare incident.