Marine survey in Atlantic off Mayo coast

THE Department of Transport has been advised of a geophysical marine route survey operation in the northeast Atlantic, off the Mayo and Galway coast.

Survey activity began on June 7 and is scheduled to be completed by early November, weather permitting.

A marine notice published ahead of the operation said all survey activities will take place within the Irish TS, Irish CZ and Irish EEZ.

The survey will be conducted by the RV Ridley Thomas, which will undertake 24/7 cable route survey operations.

Survey operations will include the stern deployment of a sonar towfish tethered with steel cable at varying water depths to collect geophysical/bathymetric mapping data for a proposed undersea telecommunications cable.

The towfish towing wire layback will be three times the water depth behind the vessel stern.

The maximum depth of the tow operations will be 100 metres. The sonar sensor will be towed approximately 20-40 metres from the seafloor.

The survey corridor is 500 metres centred on the survey centreline and will include cone penetration tests and gravity coring. This will take place outside of the 12 nautical miles boundary only to the end of survey operations within the EEZ; total length of the centreline is approximately 175 kilometres.

All vessels operating within the area have been requested to keep their distance, maintaining a safety zone around the survey vessel, and pass at minimum speed to reduce vessel wash.

The full notice is published on gov.ie.