Irish and British Coastguard units are to participate in the first joint counter-pollution, salvage and search and rescue exercise on Lough Foyle today.
Code-named "Drontheim", the exercise will also involve the North's Environment Heritage Service (EHS), Donegal County Council and the emergency services and port authority in the Foyle area of Co Derry.
The exercise is expected to continue until tomorrow and will be co-ordinated by a salvage control unit and a marine response centre. The aim is to test how the Irish Coast Guard and the British Maritime and Coastguard Agency (MCA) work together, along with the associated agencies.
A "major marine accident" will be simulated on the lough, and those involved will respond to the situation as it unfolds, according to Mr Mark Clark of the MCA.
The EHS will be testing its response to shoreline pollution, and an environmental group will also be established for the exercise to provide advice on the environment, fisheries and public health to the counter-pollution teams. The Bord Iascaigh Mhara college in Greencastle, on the Inishowen peninsula, will provide the base for the exercise "control".
"Exercises of this kind are invaluable in testing multi-agency search and rescue, counter-pollution and salvage procedures during a major incident at sea," Mr Brett Cunningham, controller with the MCA, says.
"The exercise will place heavy burdens upon the various response organisations and should be testing, while still allowing the opportunity for learning."
The Irish and British rescue agencies have held joint search and rescue operations and training in the Irish Sea, but this will be the first of its type to involve environmental response elements and salvage. Earlier this year, the Irish Coast Guard was involved in a major counter- pollution response in Donegal when fuel had to be offloaded from the single hull oil tanker, Princess Eva.