2009:737 - LISHEEN WIND FARM, BARNALISHEEN/DERRYVILLE/ KILLORAN/COOLEENY/DERRYFADDA, Tipperary

Test excavation took place at the Lisheen wind farm extension, Co. Tipperary. The northern and southern proposed extensions to the wind farm, in open countryside with a mixture of bog, forestry and arable land, were tested. The permitted development consists of twelve wind turbines of 95m hub height and blade diameter of 90m, three borrow pits, construction of internal site tracks, upgrading of existing access tracks and associated works. No subsurface archaeological deposits were encountered in the northern extension. Potential archaeology in the form of a liner double ditch was revealed in the southern extension close to the proposed location of Turbine 30. This may have medieval association to a previously unrecorded enclosure c. 100m to the north-west. Local knowledge states that the now-inaccessible interior of the enclosure retained the collapsed remains of a church wall. The assessment was conducted between 27 January and 11 February 2009. Test excavation occurred between 15 and 21 December 2009 using a mechanical excavator.
Test-trenches were excavated up to 2m in width along the full extent of the proposed wind turbine and adjacent hard-stand locations as well as the three borrow pits in Lisheen South. At the time of test excavation, Turbines 24 and 25 (and hardstands) proved inaccessible due to forestry at these locations. However, it is proposed to test-excavate these areas post-tree-felling, prior to commencement of works.

The proposed new trackways or roads received 30% testing. Ten-metre-long trenches were excavated along the line of the roads and set apart by 20m intervals. Within Lisheen North, Turbines 22, 23 and 26 received 80m test-trenches. Ten-metres of new road associated with Turbine 26 were test excavated. The remainder was inaccessible to test excavation due to density of the existing forestry; however, these locations will be assessed at a later date post-treefelling. The proposed new road sections from Turbine 22 to Turbine 23 (including a short section to the south-east of Turbine 23) had 230m of test-trenches excavated over a distance of 700m. The remaining road section will involve upgrading of the existing track.
In Lisheen South, test-trenches were excavated at Turbines 27 (70m), 28 (80m), 29 (75m), 30 (80m), 31 (80m), 32 (80m) and 33 (80m). The proposed new road commenced at the south-west end of the site c. 200m south of Turbine 32. It will link from this point to an existing farm track that will receive upgrading. The remainder of the site will entail construction of the new access road. This will be 3.41km in length, of which testing took place at lengths of 10m trenches set 20m apart (30% coverage).
The 57 test-trenches in Lisheen North achieved depths consistent with the surface of the natural subsoil. The depths varied between 0.2m and 0.55m. Turbine 26 showed the greatest variation in stratigraphy. It was excavated in forestry and comprised up to 2.5m of peat, overlying grey silt with limestone bedrock outcrops.
In Lisheen South 104 trenches were excavated. In general the depth of the trenches varied between 0.1m and 0.4m. Between the south-western extent of the proposed new road and Turbine 30 (Cooleeney), the trenches were 0.1m to 0.35m in depth. The depths of the test-trenches increased to 0.4–0.65m for part of the proposed road, from c. 60m east of Turbine 27 over a length of 80m.
The western half of the proposed development (Derryfadda) retained a different stratigraphy. This higher land had clay topsoil varying in depth from 0.1m to 0.3m, with some trenches between Borrow Pit 1 and Turbine 30 receiving depths of 0.35–0.45m. New road trenches from Turbine 28 to Borrow Pit 2 were some of the shallowest at 0.1–0.2m in depth. This was due to the shallow nature of the limestone bedrock. The stratigraphy consisted of clayey topsoil overlying yellow/pale-brown stony silty clay. The stratigraphy altered from Turbine 30 eastwards into Cooleeney to dark peaty topsoil over grey/white silty clay.
Some features were identified in a number of test-trenches. The remains of 19th-century deposits were revealed in Trench 61. This was situated in the northwest corner of the field in which Borrow Pit 3 is located and on the line of the new road. A 10m north to south trench was initially excavated. Upon exposure of this deposit, the trench was extended to 15m in length and a further eastward perpendicular spur (measuring 2.5m north to south by 2.2m) was excavated to uncover the full extent of the feature. The feature was mechanically excavated to its basal level along the original north to south trench line. Assessment of the feature identified some animal bone (sheep or goat), red brick and some glass. The majority of the deposit consisted of small to large angular limestone. It was initially thought that this may have been the infill of a quarry. However, no bedrock was exposed. The deposition of the material was interpreted as the infilling of a natural hollow, possibly to level the field. The animal bone and other material was seen as the opportune dumping of material or rubbish while infilling the hollow. Local knowledge asserts that eighteen families once lived in the area during the pre-Famine period. The remains of a number of derelict farmsteads survive in the area. The deposit was therefore interpreted as agricultural landfill, with domestic refuse contemporary with this period. It was roughly oval in plan, measuring 9m north to south by 4m. In profile the deposit’s edges were shallow, at 0.1–0.15m on all sides, which defined a shallow profile to a maximum depth of 0.4m in the centre.
Trenches 86 and 93 revealed a parallel ditch feature excavated into the natural subsoil. It had no surface indications. Trench 93 was excavated along the line of Turbine 30 and its associated hardstand area, while Trench 86 was situated in the field to the north of the turbine and on the line of the new road, immediately to the north-west of Turbine 30. The enclosure known as ^the monastery’ is situated 100m to the north-north-east. The enclosure is on the crown of a west-facing slope and the parallel ditch’s orientation appears to run broadly parallel to the base of the slope, of which the revealed portion is c. 10–15m west of the base of slope. It is orientated north-west to south-east. The easternmost ditch was situated in the western extent of Trench 86, while its more western counterpart fell between Trenches 86 and 87 (to the west). The ditches were excavated. The easternmost ditch was exposed in the northern end of the test-trench. It ran from the trench’s end diagonally in the eastern baulk, without showing its eastern extent. The trench was therefore mechanically extended eastwards for 2.5m at 2.4m from its northern end.
The general stratigraphy consisted of 0.3m of sandy topsoil overlying yellow/grey silty clay with frequent inclusions of small decayed and undecayed limestone. The ditches were dug into the subsoil and retained a topsoil fill that was more silty in nature. They were set between 3.8m and 4.2m apart, with the western ditch running from the trench’s western end into its eastern baulk, appearing at 7.6m from the trench’s northern end and disappearing at 34m from the trench’s southern end. The dimensions and profile of this trench were found to be the same as in Trench 86.
The eastern ditch measured 2.2m in overall width and formed a shallow south-west to north-east profile, receiving an overall depth of 0.22m into the natural subsoil. The western ditch was narrower, at 1.6m in width. It had a similar profile and was 0.17m in maximum depth. No artefacts or other materials were found in the excavated portions of the ditches. Similarly, there were no other deposits or features found in the trenches. The soil surface between and overlying topsoil between the ditches had no additional materials. The available evidence therefore suggests that it does not appear to have functioned as a road. Townland boundaries can frequently be marked by a double-ditch structure.

However, they tend to be closer together and have deeper profiles. The double-ditch feature is not situated at a townland boundary, the nearest of which is 150m to the west. It runs in a north to south direction and comprises a significant drainage channel, roughly halfway between the proposed locations of Turbines 27 and 30. It may be possible that the double ditch has some association with the enclosure, given their relative proximity. It is considered that this feature should be treated as archaeological in nature and resolved accordingly.