Having only just started working on the controversial tunnel, Shell’s engineers are already facing significant problems.
As local people always predicted, the doib, an unusual blue/grey mineral soil found under peat bog, is causing issues.
This is the first time such a machine has had to deal with this unstable viscous material. This once again highlights the experimental nature of the project.
Despite having taken more than a year to design and build, according to our sources the TBM got stuck after 30 meters having only just reached the doib. As we write there’s no end in sight for this headache.
The tunnel and pipeline cuts right through Sruwaddacon Bay which is a designated conservation site, a candidate Special Area of Conservation (SAC) and Special Protection Area (SPA).
Shell has insultingly named the Corrib TBM ‘Fionnuala’ after the female of the Children of Lir, one of the legends most closely associated with the Erris region.
Although the environment’s help is welcome, we could always use more people here. Now that the spring is here come and help make 2013 another unlucky year for Shell.
Background information on the tunnel (source : Shell.ie) :
“The TBM for the Corrib tunnel was designed and built in Schwanau, Germany by Herrenknecht, one of the world’s largest makers of TBMs.”
“The tunnel will have an external diameter of 4.2m and an internal diameter of 3.5m and will run at depths of between 5.5m and 12m under Sruwaddacon Bay”
“When constructed, the tunnel will [if it’s built] be the longest tunnel in Ireland and the longest gas pipeline tunnel anywhere in Europe.”
“As the TBM moves forward, a series of 1.2m wide concrete rings made up of precast interlocking concrete segments is erected. These concrete rings, which are fabricated in Ireland, will eventually line the entire tunnel.”
“As the cutter head rotates, hydraulic cylinders attached to the spine of the TBM propel it forward a few feet at a time.”