Oil company Shell will apply for permission to tunnel under the seabed off the Mayo coast in the Republic of Ireland as part of the latest plan to get gas from the Corrib field.

Shell plans to build a 5km pipeline with a 3.5m diameter 5m below the seabed at Scruwaddacon Bay. An option for an open trench pipeline through the bay will also be submitted to An Bord Pleanala (ABP), Ireland’s Planning Board.

The plan will cost up to EUR 100M (USD 133M).

Shell will submit the plan because it believes that a tunnel cutting through the bay is ABP’s preferred option.

In a letter to Shell, ABP gave the directions to “modify the pipeline route, so the route at this location would be within Scruwaddacon Bay.”

The letter said the development should include a revised environment impact statement.

When Shell submits the new applications, a period of public consultation is likely to take place again. This is expected to cause delays to the project.

Shell has advertised for tenders for specialist contractors to bore the tunnel. Construction of the tunnel would take at least one year.