The Office of Public Works has denied there is any threat to the Unesco World Heritage status of Skellig Michael, off the Kerry coastline, as a result of works being carried out on the national monument.
The OPW was responding to a debate on an archaeologists' website over its management of the monastic island, sparked off by Connemara-based archaeologist Michael Gibbons.
Mr Gibbons says he is seriously concerned about accidental damage caused to the island's South Peak oratory or hermitage, built by the monastic community sometime between the 6th and 8th centuries, and comprising three separate terraces on the edge of rock some 218 metres above sea level.
In a submission to the Institute of Archaeologists of Ireland (IAI) forum, which he has forwarded to the Heritage Council, Mr Gibbons says that such damage took place under OPW contract, resulting in "over-restoration" of sections of the oratory and replacement of original stonework.
This "over-restoration" has resulted in a "reconstruction" of sections of the oratory, rather than conservation of the original, he claims. "We do not allow potters to restore our Bronze Age pottery or goldsmiths to repair the Ardagh Chalice, nor should we allow unsupervised and untrained workmen - no matter how skilled in the art of rebuilding - to restore the jewel in the crown of Western monasticism."
Mr Gibbons questions the absence of published management and evaluation strategies for the monument, as required by Unesco World Heritage status guidelines, which would have ensured that such unauthorised work was not undertaken.
Independent evaluation is critical to preventing over-restoration of sites, and no restoration should be done on the Skelligs beyond the "absolute minimum necessary", he said.
OPW archaeological and architectural staff members Grellan Rourke, Dr Ann Lynch and Edward Bourke have refuted Mr Gibbons's criticisms, describing them as "ill-informed and unjustified". The project team is highly skilled and multi-disciplinary, they state, and any dry-stone work by masons is inspected by an architect and archaeologist.
The OPW has acknowledged the absence of a management plan, but said a management strategy was set out in the 1996 application for World Heritage Site status. The "formal process of preparing a management plan" has been initiated by the Department of the Environment, and OPW officials will play a full role in this.
It adds that a detailed report was prepared by the Department of the Environment in 2005 as part of a periodic review of the World Heritage Site designation.
Heritage Council chief executive Michael Starrett confirmed that it had received a complaint about the work on Skellig Michael, which it had forwarded to the Department of the Environment for evaluation before making any formal comment.