Officials insisted Donegal had not been overlooked by the Government's crisis response team - despite claims of a missing map at its control centre.
While detailed charts for the east, west and south of Ireland hung at the heart of the National Emergency Co-ordinating Centre in Dublin on Monday and Tuesday, none were on display for the most northern county.
Staff at the HQ flatly denied any blunder, claiming number four in the series of Ordnance Survey maps, showing the northern end of the island, had been removed for a senior civil servant to use in a back office.
A top official in the taskforce said the maps on the wall changed from time to time, with those on display in the control room only a sample of what was available.
"The maps that were used were computer generated which allowed Met Eireann to overlay stuff on them," he said.
"The maps that are up on the wall are part of a series of maps that we have. If someone had gone in here four weeks ago the only maps they would have found would have shown Malahide because of an exercise being carried out.
"We also have a sophisticated facility for printing large maps, literally at the flick of a switch."
Donegal Fine Gael TD Joe McHugh, who questioned whether Donegal really had become the "forgotten county", was given a tour of the emergency response centre to assure him the maps of his home county were available.
The taskforce official said charts and maps used in planning response to the volcanic ash crisis were provided on an overhead projector and TV screen.
The official said the ordnance survey map covering the most northern county had been removed by a member of staff at the centre and was posted to a separate conference room.