The NRA's archaeological survey work on the route of the M3 has been diligent and thorough, suggests Fred Barry
The discovery of what the National Roads Authority (NRA) believes to be a national monument at Lismullin on the route of the M3 motorway has generated much comment about the archaeological investigative practices of the NRA and the nature and significance of the site.
The M3 project is the product of a four-year planning process which began in 1999, leading to An Bord Pleanála's decision to approve the proposed motorway in 2003. This followed a 28-day oral hearing which addressed all issues of concern, including potential impacts on the Hill of Tara and the archaeology of the area.
That process, which included 10 route options, took into consideration engineering, the environment, archaeological sensitivities, safety and cost.
The selected route was regarded by the county council and the NRA as the best because it gave archaeological protection a high priority in balance with other needs such as:
avoiding house demolition where possible;
avoiding placing the motorway too close to houses;
limiting the fracturing of residential communities;
minimising the splitting and disruption of farms;
minimising visual, noise and air quality impacts;
ensuring the route fulfils its transportation purpose.
The authority takes seriously its responsibilities in relation to archaeology and commits significant financial and personnel resources to ensure that archaeology is dealt with at all stages in full compliance with legislation.
We expect to spend in excess of €200 million on archaeological work on national road schemes over the seven-year period of the National Development Plan. For the M3 project, we have spent €23 million to date on archaeology, and more than 400 archaeologists have been employed.
The M3 involved desktop, field and geophysical surveys, following which the scheme was archaeologically tested. Some 160 sites were identified in 2004, including Lismullin, and seven additional sites also came to light. This rate of discovery is consistent with experience on other national road schemes.
The interim results of this archaeological work have been extensively publicised via a dedicated M3 website (www.m3motorway.ie), NRA Archaeological Discoveries series leaflets, and articles in Archaeology Ireland and the NRA's new archaeology magazine Seanda.
In relation to Lismullin, a total of 810 objects were recovered during the topsoil assessment and, typically, the majority of these were modern in the form of nails, bolts and other agricultural debris.
Upon completion of the topsoil assessment, careful mechanical topsoil removal commenced. This was carried out slowly, using flat-bladed buckets, and under constant archaeological supervision and control. The site was revealed to be a series of smaller sites of varying dates from Bronze Age to early modern.
The whole area was then trowelled by hand in order to identify all archaeological features. Additional features were identified during this phase of archaeological review. They consisted of a series of arcs of small stakeholes which were not visible prior to excavation, because surface evidence had been removed by centuries of ploughing. The stakeholes are small, shallow (15-25cm, six to 10 inches) and difficult to distinguish from the sub-soil.
No one archaeological assessment technique can identify all archaeological remains hidden below topsoil.
It is widely acknowledged throughout Europe that archaeological test trenching, as used by the NRA, is the most successful methodology for identifying such sites. A combination of extensive testing and geophysical surveys, as carried out on the M3, is acknowledged as archaeological best practice. It was the combination of these phases of careful and deliberate assessment that led to the discovery of the enclosure at Lismullin.
The significance of the site was established by NRA archaeologists, and an on-site meeting was held with both the Department of the Environment's chief archaeologist and the director of the National Museum. Following this, the authority submitted its findings to the Minister, who will issue his directions in due course and the NRA will fully implement them.
The M3 will comprise a total of 110km (68 miles) of new road and a further 34km of access roads. Work is continuing, with the exception of a zone in the vicinity of the Lismullin site.
After years of delay during the planning period and legal challenges (all of which supported the professionalism of those acting on behalf of the NRA and Meath County Council), we look forward to finally improving the quality of life, and the safety, of today's residents of Meath and Cavan.
Fred Barry is chief executive of the National Roads Authority