2016:029 - Belcamp, Balgriffin, Dublin 17, Dublin

Testing was carried out at the site of a proposed mixed-use residential and commercial development at Belcamp Hall, Balgriffin, Co. Dublin in response to a request for further information from Fingal County Council (Planning Refs.: Fingal Co. Co. F15A/0609, Decision order PF/0263/16). The assessment incorporated the results of a geophysical survey of the development area and test trenches were placed based on the results of that survey.

The proposed development site is located to the north of the N32 and north of the Mayne River and is bounded to the east by the R107 (to Kinsaley and Malahide) and to south-east by existing industrial development. It comprises the lands of the former 18th-century demesne of Belcamp Hall and was in use as a school until 2009 (Belcamp College), which was run by the Oblate Fathers since 1893. Two archaeological sites are recorded within the proposed development area boundary, the site of a ringfort (DU015-033) and a ring-ditch (DU015-116).

Testing took place over 4 days from 3 May 2016 and no features, finds or deposits of archaeological significance were identified. The sites DU015-033 and DU015-116, which were previously thought to be a ringfort and a ring-ditch respectively, have been shown, as a result of test trenching, to be early modern landscape design features, possibly tree-rings.

In total 18 test trenches were excavated within the greenfield area in the eastern half of the proposed development site, to determine the nature, date and extent of the cropmark sites and to investigate potential landscape design features identified on aerial photography. These features were thought to relate to the entrance alignment of an earlier house at the site. Testing also targeted other potential features identified during the geophysical survey.

In general the topsoil was 0.3m deep across the field and contained many 19th- and 20th-century finds such as delph, glass, brick fragments, sea shells and nails. For the most part the topsoil overlay compact yellow silty sand with occasional variations to yellow sandy clay and yellow grey sandy gravel in places. No features or finds of archaeological significance were identified in any of the test trenches. Modern agricultural furrows oriented east-north-east/west-south-west were identified throughout the field and in trench T5 an earlier set of furrows were also identified oriented north-south. Other than the furrows, the natural subsoil was sterile and had the appearance of having been reduced or levelled somewhat in the past and this corresponds well with the field having been previously used as playing pitches for the school.

Trench 16 was placed to assess enclosure DU015-033 which was indicated through aerial photography and geophysical survey. Two ditches were identified in the trench corresponding to the results of the geophysical survey. Two sections were hand excavated across the ditches which were found to measure a maximum of 2.25m in width and 0.6m in depth. The fills of these two ditch sections indicated that they were the same feature and the enclosure indicated on the geophysical survey and aerial photographs. The ditch sections each contained three fills. The upper fill (C14) comprised a loose brown deposit similar to topsoil, 0.1m deep. Below C14 most of the ditch was filled with what appeared to be redeposited natural subsoil which contained snail shells, sea shells (oyster), red bricks, glass and slate fragments (C15). The basal fill (C16) was a clayier version of C15 and contained similar finds to those recovered from C15. A stone drain (C18) was also present within this ditch, along the outer edge in both sections excavated, and it appeared from the fills that it was part of the original construction of the ditch feature. The combination of the modern finds recovered from the fills and the drain within the outer edge suggest that this feature is an early modern landscape design feature, rather than a ringfort as was previously thought. Based on the testing results this enclosure has an outer diameter of c.14m.

Trench 11 was placed to assess enclosure DU015-116 which was also indicated through aerial photography and geophysical survey. Two ditches were identified in the trench corresponding to the results of the geophysical survey. Two sections were excavated across the ditches with the careful assistance of a mechanical digger guided by hand excavation and were found to measure a maximum of 2.7m in width and 1m in depth. The fills of these two ditch sections corresponded with each other, indicating that they were the same feature as the enclosure indicated on the geophysical survey and aerial photographs. The basal fill (C12) was a gritty grey clay 0.08m deep and it was overlaid by a pure yellow grey silty clay 0.18m deep (C10). Above C10 was a deposit of grey-yellow silty clay 0.18m deep with frequent inclusions of snail shells and some inclusions of red bricks (C9). Above C9, C8 made up the bulk of the fill of the ditch. C8 was 0.3m deep comprised yellow clayey silt with frequent small stones and snail shells. This deposit appeared to be comprised of redeposited natural subsoil. Above C8 was a deposit of mid-brown soft sandy silt 0.14m deep with some modern inclusions (C7). The ditch was sealed by a dark brown deposit localised to the ditch with frequent modern inclusions (C6). Like enclosure DU015-033, a stone drain (C13) was also present within this ditch, along the outer edge in both sections excavated, and it appeared from the fills that it was part of the original construction of the ditch feature. The combination of the modern finds recovered from the fills and the drain within the outer edge suggest that this feature is an early modern landscape design feature, rather than a ring ditch as was previously thought. Based on the testing results this enclosure has an outer diameter of c.24m.

Faint responses suggestive of a further enclosure were identified in the geophysical survey in the east of the area and trenches T2, T3 and T4 were placed to investigate these anomalies. Variations in the natural subsoil present in trenches T3 and T4 may have caused these responses and test sections excavated through these variations confirmed the deposits as natural subsoil.

Courtney Deery Heritage Consultancy, Lynwood House, Ballinteer Road, Dublin 16