A UNESCO report on State management of the world heritage site at Skellig Michael off the Kerry coast has found that conservation works have "dramatically altered" the appearance of surviving remains on its South Peak.
However, the 6th century monastic outpost will still retain its "outstanding universal values" intact if the conservation work is documented in an academic publication, the Unesco mission report has found.
The report, due to be released today by the Unesco world heritage committee in Quebec, Canada, has been welcomed by Minister for the Environment John Gormley. He is also publishing the first management plan for Skellig Michael today.
The Unesco study upholds some of the criticisms of State stewardship to date, in recommending that a site manager be appointed. It also says that a "durable agreement" should be negotiated with Skellig Michael ferry operators.
It recommends that an academic advisory committee be appointed by the Office of Public Works (OPW), and it is critical of the OPW for failing to consult with archaeologists and other stakeholders before embarking on the South Peak conservation works.
The Unesco mission to Skellig Michael took place late last year as a result of concerns highlighted by independent archaeologist Michael Gibbons, and submissions from organisations such as the Royal Irish Academy and the Skellig boatmen. A draft management plan had already been initiated in response to the criticisms.
While the OPW has responsibility for management of the complex, Mr Gormley's department is responsible for policy.
Mr Gibbons maintained that serious damage had been done to the South Peak oratory, including destruction of an altar. It was built by the island's monks some time between the 6th and 8th centuries when they laid out three terraces on the edge of rock some 218m (715 feet) above sea level.
An "over-restoration" by the OPW had resulted in a "reconstruction" of sections of the oratory rather than conservation of the original, Mr Gibbons claimed. He also queried why no management plan had ever been published since it was given world heritage status in 1996.
The Unesco report summarises the criticisms as a failure to apply best archaeological practice, and a perception that the OPW conservation plan was driven by "architectural rather than archaeological imperatives".
"Because the rationale for the works and the actual process was largely discussed in-house, criticisms were inevitable," it says, and this was exacerbated by a "lack of publication".
"The new work is in its own way almost as remarkable as the original work. The monument as now reconstructed will become the popular vision of Skellig. For this reason it is essential that detail of the works should always be made explicit and the new work should be distinguishable from the old in all future publications," the report says.
In securing an agreement with the Skellig boatmen, the Unesco committee recommends that the OPW invites the boatmen to an annual meeting, and it should establish and publicise future criteria for the issue of permits.
It also emphasises the need for a site manager to liaise between official and stakeholder interests. It says that a detailed visitor study should be carried out and an environmentally acceptable solution should be found to the lack of toilet facilities on the island.
Mr Gormley has welcomed the "very positive findings", and says that his 10-year management plan aims to "protect, conserve and promote an appreciation of Skellig Michael".