The pipeline route

The whole area is completely unsuitable as it is both a Special Area of Conservation and Special Protected Area. The land is also boggy and has a history of both landslides and bog fires. There would actually be 3 pipelines: unrefined gas, electric cables and outfall pipe containing toxic chemicals. This development is so unprecedented that there is no relevant legislation and regulations. Shell uses the same landfall site for all the routes and intends to build an experimental valve station on part of the Broadhaven Bay Special Area of Conservation. The European Court of Justice has recently ruled against Ireland in relation to the implementation of the EU Birds Directive.

Proposed pipeline route

The Pipeline
The Corrib pipeline is not a ‘’normal’’ pipeline given its potential to operate under exotically high pressures and because of the unknown gas compositions associated with gas field production. This can seriously increase the likelihood of pipeline failure. Centre for Public Inquiry, p.6, 2005 Bord Gais pipelines contain refined, scented gas and run at 16 – 70 bar pressure. The proposed Shell pipeline contains unrefined, unscented gas and relies on an experimental valve station to reduce the pressure from 345 bar to 144 bar.

Pipeline information

1. Unrefined gas pipeline
   Proposed pipeline total length 92km
   Unrefined & untreated gas, scentless, with very high methane content, over 90% by volume
   350m under seabed
   When onshore, will be buried 4 m below ground but as it is in unstable peat, this is not guaranteed.
   27.1mm thickness pipe
   508mm /20” external diameter
   
   Pressure
   From wellhead-landfall, 83km, 345 bar
   At Land fall - pressure reduction valve (experimental) aims to reduce pressure to 144 bar, dropping to 90-110 bar after first year. This valve is not able to stop the gas in case of an emergency,
   From Landfall-Refinery 9km max. 144 bar. This of course relies entirely on the experimental pressure reduction valve which has never been used before.
2. Control Umbilical
   Carries power and communication cables and hydraulic fluid to operate the sub sea equipment, and liquids added to the gas gas to prevent it freezing and inhibit corrosion.
3. Polyethylene outfall pipelinel
   Takes waste water (including some waste chemicals) from the terminal to be discharged at sea, buried along the shore length in the same trench as the gas pipeline.

All information taken from Advantica report