The historian, Prof Roy Foster, has joined heritage groups and local residents in opposing retention planning permission granted by Offaly County Council to a controversial sawmill in the Aghancon Valley.
Prof Foster, the Irish Georgian Society, An Taisce and the Aghancon Concerned Residents' Association have appealed the retention permission for T&J Standish Sawmills (Roscrea) Ltd to An Bord Pleanála.
The move is the latest in a long-running controversy over the sawmill, which operated for several years without planning permission, and has been served by the Environmental Protection Agency with several pollution control warning notices.
This followed the discovery of Chromium VI, a carcinogenic found in wood preservatives, in local watercourses.
The sawmill is located beside Leap Castle, a protected structure and national monument built by the Carroll family in the 16th century. It is currently being restored by its current owners.
The EPA has begun legal proceedings against the sawmill, which is the largest producer of fencing stakes in the country. It also directed the owners to discontinue the use of a preservative that caused contamination of ground and surface water on the site, and to install new treatment units. In 2003, Bord Pleanála overturned an earlier retention permission after finding that "no part of the existing development on the application site is authorised by way of planning permission".
However, the sawmill continued to operate, and its owners told council enforcement officers that most of the 50 staff were prepared to go to jail in defence of their jobs. Legal proceedings brought by residents to close the sawmill were adjourned in the High Court last July. Last month, the council granted a second retention permission.