2011:021 - DRUMNAGREAGH HYDRO SCHEME, DRUMNAGREAGH, Antrim

Monitoring of groundworks within the footprint of a proposed water pump house and associated pipe trench was carried out over a two-day period between 8 March and 4 May 2011 as an extension to previous testing carried out at the site in 2010 (Excavations 2010, no. 31). Monitoring of removal of topsoil along the line of the water pipeline trench (0.35m wide) from the pump house to the eastern corner of the field boundary and the footprint of the pump house itself (2m x 2m in size) revealed topsoil 0.3–0.4m deep lying directly on an orange stony, gravelly boulder clay subsoil; no archaeological deposits were noted within either of these two trenches. Monitoring of removal of topsoil from the line of the proposed pipe trench up through the southern portion of the PDA revealed topsoil to range in depth from 0.2m to 0.4m from south-west to north-east. During removal of topsoil three areas of potential ditch activity were noted c. 20m from the north-east field boundary and 16–24m from the south-west field boundary, each surviving as a deposit of dark brown loamy soil containing light charcoal flecking.

The narrowness of the pipe trench (0.3–0.4m wide) hindered hand excavation of these features. Further monitoring of pipe trench excavation carried out on 4 May confirmed the existence of three large, ditch-like features. Ditch 1 was uncovered 19m from the north-eastern boundary of the site and survived as a large, subsoil-cut feature c. 2m wide and 0.6m deep, extending along a north-west/south-east alignment. The basal fill of the ditch consisted of a 0.2m-thick deposit of dark brown/grey stony clayey silt, while the remainder of the ditch was filled by a dark brown–black mottled orange silty clay containing a few large stones/boulders. Towards the south-western end of the field a further two ditch features were uncovered. The first of these (F5), 16m to the north-east of the field boundary ditch, was the most substantial. It survived as a subsoil-cut feature 3m wide and 1.35m deep with steep sides and a flat base. Three main deposits were noted within its fill. A 0.3m-thick basal deposit consisting of a mid-brown mottled orange, loose sandy gritty silt containing light charcoal flecking was overlain by a mid-brown sticky silty clay which was lightly charcoal-flecked and from which a number of fragments of animal bone (cattle metacarpal) were recovered during sampling. The ditch was capped by a black friable silty clay containing charcoal flecking. A second, less substantial ditch was noted a further 1.75m north-east of ditch F5, again surviving as a subsoil-cut feature 2m wide and 1.25m deep. Several fill deposits were noted from within the ditch. The basal deposit consisted of a grey/brown sticky clay containing numerous medium-sized (c. 0.25m) stones. This was overlain by a backfill deposit of black sticky silty clay, moderately charcoal-flecked, which in turn was overlain by a capping deposit consisting of a mid–dark brown friable silty clay containing a number of small stones. A small deposit of orange/brown redeposited subsoil also capped the ditch. No finds were recovered from this feature during sampling.

Archaeological investigations associated with the proposed insertion of a hydro-electric power scheme at Drumnagreagh, Glenarm, Co. Antrim, were carried out in response to planning conditions imposed upon the development by the NIEA Historic Monuments in relation to the existence of Scheduled Monument ANT030-003, an ecclesiastical site of early medieval origin located adjacent to the south-eastern boundary of the site. Archaeological evaluation in the form of hand-dug test pits adjacent to the south-eastern boundary indicated the existence of a shallow ditch extending north-east/south-west across the eastern end of the site. The recovery of several fragments of struck flint and Bronze Age pottery suggested a prehistoric date for this feature.

Further monitoring of groundworks associated with the excavation of the proposed water pipe trench also uncovered three more ditch features, which appeared to extend north-west/south-east across the field. While no datable artefacts were recovered from these features, a number of animal bone fragments recovered from the ditch at the north-west end of the site suggest a similar function to that uncovered during testing.

The small-scale nature of development works at the site—ground reduction works being confined solely to the excavation of the pump house and pipe trench—has produced partial evidence for archaeological activity within the PDA. Excavation of the 0.4m-wide pipe trench has positively proven that archaeological remains do extend across the development area, but the limited nature of excavation works makes it difficult to ascertain the true extent and nature of these remains, outside that of identifying a series of subsoil-cut ditches.

FarrimondMacManus East Belfast Enterprise, 308 Albertbridge Road, Belfast BT5 4G