Mynydd y Gwair Wind Farm - RWE.com

Contents 

Mynydd y Gwair Wind Farm 

9 Non Avian 130 

9.1 Introduction 130 

9.2 Baseline Ecological Conditions 131 

9.3 Results 134 

9.4 Habitat and Botanical Survey Results 136 

9.5 Evaluation of the Ecological Resource 148 

9.6 Assessment of Impacts 154 

9.7 Mitigation and Monitoring 162 

9.8 References 175 

Appendices (Volume 2) 

A9.1 Citations of SSSIs 

A9.2 Bat Survey October 2005 

A9.3 Bat Survey October 2007 

A9.4 Bat Survey May 2010 

A9.5 Bat Survey June 2010 

A9.6 Invertebrate Habitat Appraisal 

A9.7 Selection Criteria Checklist 

A9.8 Badger Survey Report 

A9.9 Peat Survey Report 

Figures (Volume 3) 

Fig 9.1 Non Avian Ecology Study Area 

Fig 9.2 Habitats on the Main Study Area 

Fig 9.3 Peat Resources 

Fig 9.4 Habitats on Blaen Gerdinen and Blaen Yr Olchfa Fach Survey Areas

9 Non Avian 

9.1 Introduction 

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9.1.1 This chapter deals with the potential impacts of the proposed wind farm on ecological 

resources other than ornithological (avian or bird) assets. 

Explanation of Study Areas 

9.1.2 Ecological studies commenced in 2004, early in the evolution of the project, and baseline data 

has therefore been collected in various areas in and around the current application site. 

These various ecological study areas are shown in Figure 9.1. 

9.1.3 A much broader area of land than the current application site was covered initially, both to 

inform the development design and also to ensure that baseline use of the locality by wideranging 

species such as birds of prey was covered at a wider range than simply where 

turbines and other wind farm infrastructure were likely to be built. In response to initial 

surveys, scoping and consultations, additional areas of land were brought in for particular 

specialist studies. 

9.1.4 As the project design developed, and the preferred location of the turbine array and access 

infrastructure was decided, later phases in the baseline survey process became more 

focused. The wind turbine locations within the application site have themselves been selected 

by an iterative process taking into account the results from the wider ecological study area as 

well as other environmental and technical disciplines. 

9.1.5 The study areas shown on Figure 9.1 comprise: 

Main Study Area (MSA) – the Main Study Area equates to the original site boundary 

(see Chapter 3, Site Selection) at the beginning of the site design process in 2004. As a 

consequence it covers what is now the proposed wind farm site and also significant areas 

beyond the application site boundary. The boundaries of the MSA are roughly defined by 

Pentwyn Mawr to the north-west, Penlle‟r Castell to the north-east and they wrap around 

the Lliw Reservoir to extend onto Banc Maestir Mawr and Mynydd Garn Fach to the 

south. 

Bat Study Areas – targeted areas within the MSA where bat transects and emergence 

studies were carried out are shown on Figure 9.1. Each transect or emergence site is 

shown in greater detail in Appendices 9.2 to 9.5. 

Access Route Study Area - this comprises those parts of the proposed wind farm 

access route that lie outside the Main Study Area. By way of cross-reference with the 

Wind Farm Terminology Plan (Figure 1.3) this comprises Section 1 of the Access Route 

(new track) and all portions of Section 2 (existing road) where works might be needed 

that could affect habitats or species off the existing tarmac. It should be noted that the 

numbered points and „segments‟ used to describe individual parts of the route in this 

chapter are not the same as the „sections‟ used elsewhere in this ES. Studies along the 

access route formally included 30m either side of the proposed track but in practice the 

habitats are so open that features within 50-100m of the line were clearly visible. The 

Access Route Study Area with the numbered ecological survey points and segments is

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shown on Figure 9.1. 


Blaen Gerdinen Study Area – is a holding of five small fields, the location of which is 

shown on Figure 9.1 with greater detail on Figure 9.4. One field, (where the proposed 

substation will be located) falls within the application redline and overlaps with the MSA. 

The other four fields would comprise exchange land for the purposes of the Commons 

Application (see Chapter 13 Land Use). 

Blaen yr Olchfa Fach Study Area – this is a larger holding to the south-east of the 

Upper Lliw reservoir wholly earmarked for exchange land for the purposes of the 

Commons Application (see Chapter 13 Land Use). It is shown in detail on Figure 9.4 with 

the location relative to the application site shown on Figure 9.1. Structure of Chapter. 

9.1.6 This chapter commences by describing the methods used to gain an understanding of 

existing ecological conditions within the various study areas, and then presents and evaluates 

the results. The impact assessment methodology is then described, followed by consideration 

of the design measures taken in the course of wind farm design to avoid or reduce ecological 

impacts. The likely significant effects before any applied mitigation or compensation 

measures are then assessed. Applied mitigation, compensation and monitoring measures are 

then described, with an assessment of their likely effectiveness and the means by which they 

would be secured if consent for the wind farm is given. Cumulative and residual impacts are 

then assessed. 

9.2 Baseline Ecological Conditions 

Methodology 

Consultation 

9.2.1 At the commencement of the project in 2004, the requirements, methodology and scope of 

the ecological studies was established in consultation with officers from the Countryside 

Council for Wales (CCW). Formal Scoping Opinions were received in 2004 from CCW and 

RSPB (Appendix 1.1). 

9.2.2 Further consultation was carried out with CCW during 2007 to ensure the data collected since 

2004 was updated appropriately. As a result of this a further bat survey was undertaken in 

Autumn 2007 and badger surveys were continued on an ad hoc basis as an adjunct to the 

monthly bird studies. Surveyors undertaking these studies also checked for any changes in 

habitats up to the end of 2007, and for the appearance of additional species (e.g. otter 

activity) that had not been recorded before. Additional checks of habitat at the locations of 

potential widening works along the access route were carried out in July 2008. 

9.2.3 Following the submission of the planning application for a previous 19 turbine scheme in 

2008, CCW submitted an objection on the grounds of inadequate information on visual impact 

and bats. In the wake of this a survey protocol was devised in consultation with CCW for 

further bat work, which was duly carried out in September 2009. Further supplementary 

surveys were also carried out in May and June 2010. 

9.2.4 The most recent round of consultation with CCW was in late 2011 and related to 

supplementary work on peat depth to inform revisions to the scheme (See Appendix 9.10).

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Desk Studies 


9.2.5 Various nature conservation consultees were contacted in 2004 to request existing records 

for the area. These included CCW, Glamorgan Badger Group, Glamorgan Bat Group, 

Glamorgan Moth Group, Swansea county ecologist, the local bird recorder and the RSPB, 

plus the Welsh Kite Trust. CCW, the RSPB, the Welsh Kite Trust and Swansea county 

ecologist were all re-consulted in 2007-2008. 

9.2.6 The South East Wales Biodiversity Records Centre (SEWBReC) was consulted in 2012 to 

obtain any ecological information that has emerged since 2010. Any additional ecological 

information presented as evidence by parties at the 2010 Public Inquiry into the previous 

2008 application, and not otherwise captured by SEWBReC has also been used to inform this 

revised and updated assessment. 

Phase 1 Habitat Survey 

9.2.7 Habitat and botanical surveys relating to the project were first carried out during 2004 and 

2005, and subsequently updated by surveys in 2006, 2007 and 2008. A comprehensive resurvey 

of the habitats on the main wind farm site was carried out in 2011. 

9.2.8 Habitat surveys of the Blaen yr Olchfa Fach Study Area and the Blaen Gerdinen Study Areas 

were carried out in 2007 and 2012. The majority of these two areas will form exchange land in 

the Commons Application (see Chapter 13 Land Use). 

9.2.9 The methodology used for the habitat surveys has varied from extended Phase 1 survey 

(NCC 1990) through to more detailed botanical surveys in targeted areas of the main wind 

farm site to identify National Vegetation Classification (NVC) communities. The more detailed 

work has involved expert examination to compare the main constants and other associated 

species present and the vegetation structure with NVC descriptions and keys (Rodwell (ed) 

1991, Rodwell (ed) 1992), and in a few instances the collection of quadrat samples of more 

difficult to classify vegetation. 

Peat Studies 

9.2.10 In line with a change of position post 2008 from CCW on the depth of peat deposits 

considered „significant‟, surveys of peat depth were carried out by Bioscan in 2010 and 

submitted as Supplementary Environmental Information prior to the public inquiry that year 

(See Appendix 9.9). More recent peat surveys over the winter of 2011/12 were carried out to 

inform revisions to the turbine array and track alignment in order to minimise the impact on 

peat resources as far as possible. 

9.2.11 For the 2010 and subsequent studies carried out by Bioscan, the methodology has been 

informed by consultation and discussions with CCW, reference to guidance notes (e.g. Jones 

et al 2010) and standard methodological texts (e.g. Avery 1980). 

9.2.12 In the 2010 study (Appendix 9.9), peat depth and humification was assessed by taking 

samples with a 60mm Dutch auger, with a 30cm screw auger used for additional samples to 

assess depth and the spatial extent of peat cover. The degree of peat humification was 

assessed using the approach described by Avery (1980) which is based on the Von Post 

scale. Samples were taken along the proposed main and internal access track alignments as 

well as along two perpendicular transects centred on the proposed turbine locations at that

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time, and at various other locations where useful to inform mapping. 


9.2.13 The further targeted peat depth studies in 2011/12 used a fibre-glass peat probe to measure 

depth along a series of linear transects aligned perpendicularly to sections of proposed 

internal access track identified as affecting deeper peat. Grid sampling of peat depth was also 

carried out around two proposed turbine locations close to the edges of deeper peat deposits 

in order to inform micro-siting. The proposed sampling locations and methodology were 

agreed with CCW prior to survey work being carried out (See Appendix 9.10). 

Fauna Surveys 

Badger Surveys 

9.2.14 Searches of all study areas (other than the outer envelope of the Bird Study Area) for any 

signs of badger activity (such as setts, runs, latrines, passages through boundaries, hair, 

prints or foraging excavations) were made during the course of other studies periodically 

between 2004 and 2007, with further work carried out in 2010 following the discovery of a 

seven-entrance sett in potential conflict with the main access track alignment on Mynydd 

Garn Fach. This included detailed topographical survey of the sett itself in order to guide an 

appropriate design and mitigation response, as well as a re-survey of badger activity in the 

wider area in and around the proposed wind farm site. The sett at Mynydd Garn Fach has 

continued to be monitored up to March 2012, and continued checks of the wider wind farm 

have been made periodically to assess any changes in badger activity. 

Bat Surveys 

9.2.15 Initial bat activity surveys were carried out on 10 and 11 August 2005 and designed as 

requested by CCW in scoping consultation to gain an overview of the species present in and 

around the Main Study Area. In order to do this plantation edges and other features with 

higher potential for bat foraging were preferentially selected in order to maximise the chance 

of detecting bat activity. Three transect areas were chosen – the locations of all in relation to 

the wind farm area are shown on Figure 9.1 with further detail provided in Appendix 9.2. Dusk 

surveys of each transect were carried out, recording all bat passes both from heterodyne 

records in the field and MiniDisc recordings from frequency division bat detectors, for follow 

up analysis with the computer program „BatSound‟. 

9.2.16 Further bat surveys were carried out in the autumn of 2007 targeted on former mine workings 

in the southern part of the Main Study Area and outside it to the north (locations shown on 

Figure 9.1 and Appendix 9.3). The former areas were monitored using Duet bat detectors on 

2nd October 2007 for three hours after the first bat activity was recorded, with one accessible 

hole also watched through an image intensifier. Any bats entering, passing or circling around 

entrances were recorded. The latter area to the north of the Main Study Area was found to 

have all entrances closed with no opportunity for bat roosting. 

9.2.17 No buildings would be affected by the wind farm or construction works along its access route. 

However, there are locations in the abandoned Bolgoed-uchaf holding at the lowest point of 

the access route (Segment 1 on Figure 9.1) where trees with bat roosting potential might be 

affected by works. These trees were examined during 2004 from the ground using binoculars, 

then features with bat roosting potential were inspected more closely for bats or their signs 

(droppings, staining etc) using ladders and inspecting holes with a fiberscope and torches. 

These trees were further subjected to full tree-climbing inspections, where this was safely

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possible, in 2010. 


9.2.18 Further bat surveys of the main wind farm site were carried out in September 2009 and May 

and June 2010 using multiple surveyors walking transects designed to maximise coverage of 

the habitats or landscape features most likely to be used by bats (in particular the Lliw and 

Dulais headwater gully systems). As well as heterodyne and frequency division detectors, 

time-expansion detectors were also employed on these surveys. 

9.2.19 The bat survey reports from 2005 and 2007 are attached as Appendices 9.2 and 9.3 

respectively. These surveys were carried out by Greena Ecological Consultancy. The reports 

of the further bat surveys by Bioscan in 2009 and 2010 are attached at Appendices 9.4 and 

9.5 respectively. 

Otter and Water Vole Surveys 

9.2.20 A search of stream corridors for any signs of otter or water vole activity was made during 

2004, both in the course of other studies and supplemented by a special survey in August of 

that year. Surveys were repeated during the course of other verification surveys in the 

summer of 2005 and again in the winter of 2006 and early summer of 2007. As well as the 

MSA the surveys also covered those limited parts of the nearest shore of the Upper Lliw 

Reservoir where sufficient access permission was available for visibility. The stream corridors 

within the wind farm site were again checked for evidence of either of these species in 

summer 2011. 

Invertebrates 

9.2.21 During the baseline surveys for the previous 19 turbine planning application, the suitability of 

the upland habitat types for scarce Lepidoptera species known from the locality was 

assessed. Incidental records of invertebrate species have also been kept throughout the 

various surveys up to and including 2011. In addition, a specialist re-assessment of the 

likelihood of scarce invertebrate species being present was carried out on 2nd August 2011 

(report at Appendix 9.6), which included some direct and observational sampling as well as 

moth trapping carried out at a location in the central part of the site on the evening of the 

same date. 

Other Fauna 

9.2.22 Incidental observations of any other fauna of note have also been recorded as a matter of 

course, with particular attention paid to searching any natural refugia suitable for reptiles or 

amphibians. Waterbodies within the MSA were also assessed for their suitability or otherwise 

for amphibians, including great crested newts, being searched for amphibian eggs during 

spring and early summer visits in 2004 and 2005 where appropriate substrates were present. 

These surveys have not been repeated since because the subsequent design refinements 

have resulted in the current application site not including or adjoining any waterbodies 

suitable for great crested newts. 

9.3 Results 

Desk Study Results 

9.3.1 There are no Sites of Special Scientific Interest (SSSI) located within any of the ecological

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study areas. The site is shown in the context of designated areas on Figure 1.5 of Chapter 1, 

Introduction. 

9.3.2 Citations of nearby SSSIs are attached in Appendix 9.1. The nearest SSSIs are situated 

within 0.2km and 1.3km of the Main Study Area. These are the Graig Fawr Pontarddulais 

SSSI and the Hafod Wennol Grasslands SSSIs respectively. A further three SSSIs are 

located within 6km of the proposed wind farm site. These are detailed in Table 9.1 below. 

Table 9.1 SSSIs within 6km of the Proposed Wind Farm Site 

SSSI Distance from 

the Study Area 

Hafod 

Wennol 

Grasslands 

Graig Fawr 

Pontarddulais 

Rhosydd 

Castell-du & 

Plas-y-Bettws 

Caeau nant 

Garenig 

Ecological importance 

1.3 km west A series of hay meadows, pastures and rough grazings, 

supporting a wide range of grassland and moor communities. 

0.2km west Designated as a good example of upland vegetation 

2 km north west 

communities including dry and poorly drained acid grassland 

and soligenous mire. 

Designated for its large area of fen-meadow and drier, more 

neutral grassland, as well as associated areas of damp acid 

grassland, rush pasture and wet heath. 

2.5 km north Designated for its traditionally managed unimproved pastures 

and hay meadow. 

Nant y Crimp 6 km south-west Designated for its wet pastures, species-rich neutral grassland 

and semi-natural woodland. 

9.3.3 The Main Study Area was covered by a 1985 Upland Survey and Biological Survey of 

Common Land, the results of which were obtained from CCW and reviewed as part of this 

assessment. Although approaching 27 years old, and mapped according to the Ratcliffe-Birks 

vegetation system rather than the NVC, they allow some comparison of the vegetation 

present then with the situation both in 2004 (the time of the initial habitat surveys), and now 

(2012), affording an understanding of longer term trends in habitat condition on the site as 

well as enabling the location of any species or habitats of interest noted in the past to be 

checked. 

9.3.4 Based on this 1985 survey, supplemented with a brief site visit in 1999, the proposed wind 

farm site and much of the Main Study Area, as well as a wide surrounding swathe of upland 

extending to 1874 hectares has been identified by the City and County of Swansea as a 

candidate Site of Importance for Nature Conservation (cSINC) (Pentwyn Mawr and Mynydd 

Pysgodlyn cSINC). The selection criteria checklist for the site is attached at Appendix 9.7; the 

principal reasons for the proposed designation are the presence of UKBAP priority habitats, in 

particular Molinia-dominated rhos pastures and lowland heath assemblages scattered within 

extensive areas of Nardus-grassland. Secondary (supporting) features include the presence 

of bird and Lepidoptera species considered „scarce‟ in Glamorgan, although these are not 

defined on the checklist, as well as protected species such as great crested newt and badger. 

The Swansea ecologist has confirmed that the cSINC is based predominantly on secondary 

data derived from records held by CCW and others, and was unable, for example, to provide 

any further indication as to the specific location and/or source of the reference to great 

crested newts in the cSINC area. No great crested newt records for either the wind farm site 

or a 2km search area around it have been returned by SEWBReC in 2012, and there are no 

great crested newt records for land within 500m of the access track route. 

9.3.5 A large volume of species records have been supplied by SEWBReC for the application site

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and a search buffer that extends 2km from the main wind farm site and 500m from the access 

track route. 

9.3.6 For the wind farm site itself, there are relatively few records, most relating to bird species 

such as skylark, meadow pipit and red kite, although there are third party (i.e. non-Bioscan) 

records for hen harrier (2008), cuckoo, golden plover (flock of c.400 in April 2008) and 

common lizard (2004). Common lizard records from Mynydd Garn Fach were also provided, 

along with recent records for grasshopper warbler for that site (although not the higher, more 

exposed and heavily grazed parts crossed by the access route). Old records for grayling and 

wall butterflies from Mynydd Garn Fach were also provided, with other invertebrate records of 

note including old records for the dragonflies black darter, keeled skimmer and golden ringed 

dragonfly. 

9.3.7 Uncommon or scarce plant species attributed to locations on Mynydd y Gwair and/or Mynydd 

Garn Fach include oblong-leaved sundew, ivy-leaved bellflower and whorled caraway, but in 

all instances the locations of these are known to be outside the application site. Indeed a 

disproportionate number of the notable species records for Mynydd y Gwair or Mynydd Garn 

Fach appear to relate to areas of high quality mire north-east of the Upper Lliw reservoir 

(immediately north of Brynllefrith Plantation) and at the foot of the slopes west of the reservoir 

that were identified early in the ecological studies for the wind farm project and specifically 

avoided in the design process. Oblong-leaved sundew was reconfirmed at the former site by 

Bioscan in 2008. 

9.3.8 Amongst the records for land within 500m of the remaining sections of the access route 

(Blaennant Ddu to the A48 at Pontarddulais) are numerous uncommon or declining bird 

species, including barn owl, as well as species such as marsh fritillary and common lizard. No 

records have been received of any protected or notable species from the common land at 

Gopa Hill or the holding at Bolgoed-uchaf where the greatest levels of intervention will be 

required for farm track or path upgrades. 

9.4 Habitat and Botanical Survey Results 

9.4.1 Although the Main Study Area has been covered by habitat and botanical surveys at various 

times between 2004 and 2008, the following paragraphs focus on the habitats present within 

the current application redline and the proposed exchange land, these areas having been the 

focus of more recent studies and update work. Reference is however made to the wider MSA 

in places for context. 

9.4.2 The main wind farm site is first described (with reference to Figures 9.2 and 9.3) followed by 

the access road. The access route descriptions relate to „segments‟ of the route (labelled on 

Figure 9.1), in order to distinguish them from the access road „sections‟ referred to elsewhere 

in this ES. Finally, the baseline habitat conditions on the proposed exchange land at Blaen 

Gerdinen and Blaen yr Olchfa Fach are described with reference to the habitat maps shown 

on Figure 9.4. 

Main Wind Farm Site 

Overview 

9.4.3 The wind farm site occupies an extensive area of relatively gently undulating upland, with a 

predominantly south-facing aspect, which is incised by two main stream courses and some

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smaller tributary features. It encompasses the summit of Pentwyn Mawr as well as the 

majority of Mynydd y Gwair. The main theme of habitats and vegetation is of large and fairly 

homogenous areas of generally impoverished, grass-dominated plant communities, with 

transitions between community types typically manifested as subtle gradations spread over a 

few hundred metres, although in some places (such as the edge of former peat cuttings, or in 

discrete areas of high soil water movement) more defined edges can be seen. Boundaries 

between more or less distinct vegetation communities are drawn for convenience on Figure 

9.2 at the approximate places where they become more like one NVC type than another, but 

in reality such boundaries are frequently masked by this subtle gradation. 

Soils and Peat 

9.4.4 Given the locality, climate and altitude, variable blanket peat cover might be expected, 

however Figure 9.3 shows that the extent of deeper peat deposits on the site is restricted, and 

deposits over 0.5m (the minimum depth traditionally associated with blanket bog vegetation) 

are comparatively rare – being restricted to limited areas of the higher plateaux and some 

valley or headwater mires. This limited presence of peat can be readily observed on the site 

where the soil profile is locally exposed in gullies and ravines cut into steeper slopes. Such 

exposures betray a shallow mainly mineral soil with organic darkening confined to the top few 

centimetres of the horizon and little depth over the parent material. 

9.4.5 The main foci of deeper peat areas are shown on Figure 9.3. The deepest deposits 

(exceeding 1.5m) are associated with the valley head of the Dulais gully system, and related 

deposits extend northwards over the site boundary and across the watershed into the Afan 

Cathan catchment. Blanket peat that is generally of shallower depth also occurs on the ridge 

of higher ground between this system and the Afan Lliw gully to the east, and also on higher 

ground east of the Lliw gully. 

9.4.6 It would appear, therefore, that much of the original peat cover within the main wind farm site 

has been lost by one or more of the common causes of degradation, i.e. overgrazing and/or 

repeated cutting for fuel and burning, although disruption of peat-forming processes through 

atmospheric pollution may also be implicated. Although there are localised erosion gullies 

associated with foot and vehicle compaction and disturbance along the St Illtyd‟s Way track at 

the northern edge of the site, there is no evidence of any past attempts at artificial drainage, 

which can also initiate peat degradation. The vegetation present in the study area reflects this 

comparative lack of peat cover, being predominantly acid grassland, heath, or a commonly 

occurring degraded mire community, as described further below. 

Acid grasslands 

9.4.7 The upland slopes of Mynydd Garn-Fach to the south of the main wind farm site and crossed 

by the new-build section of access track are dominated by acid grassland conforming to 

community U5 in the NVC (mat grass Nardus stricta – heath bedstraw Galium saxatile 

grassland). Much of this area is of the species-poor subcommunity, with few species other 

than the U5 constants tormentil Potentilla erecta, sheep‟s fescue Festuca ovina and common 

bent Agrostis capillaris, with some wavy hair grass Deschampsia flexuosa. However purple 

moor grass Molinia caerulea is locally prominent on north-facing slopes, and there are also 

occasional areas where spear thistle Cirsium vulgare and other ruderal species occur, 

marking the beginnings of a transition towards rush-pasture. Poorly drained areas are also 

marked by patches and sometimes quite extensive stands of soft rush Juncus effusus, but 

with few other species. Taken together, this suggests it is possible there may have been

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intermittent attempts to improve this highly unpalatable and nutrient poor grassland type with 

fertiliser, although there is also evidence of past burning events. 

9.4.8 Moving northwards into the main wind farm site, this U5 vegetation increasingly occurs as a 

matrix with very similar U6 vegetation, characterised by the presence of heath rush (Juncus 

squarrosus). An increasingly prominent component of both these communities, and indeed 

blurring the transition between these types of upland acid grassland and mire-type vegetation 

as one continues northwards, is purple moor grass Molinia caerulea which attains high cover 

and abundance in both acid grassland and mire vegetation over much of the main wind farm 

site, but does not appear here to be indicative of any particular vegetation type over another. 

9.4.9 Other species, and particularly herbs such as tormentil and small sedges such as carnation 

sedge (Carex panicea) and green-ribbed sedge (Carex binervis), tend to be sparse overall, 

but they become more noticeable and abundant in small patches. Some of these areas of 

higher species-diversity are visually discrete, presenting an aspect of short, greener turf that 

is likely to be a consequence of higher soil water movement, consequent increased 

resistance to frost, resultant early season grass growth and therefore preferential grazing by 

livestock. These areas (termed „lawns‟ on Figure 9.2 because of their appearance) tend to be 

somewhat richer in species than the surrounding U5/U6 grasslands, with frequent small 

sedges, heath woodrush (Luzula multiflora), heath rush, mosses such as Rhytidiadelphus 

squarrosus and grasses such as velvet bent (Agrostis canina). 

9.4.10 Approaching the northern boundary of the application site, and especially on the drier slopes 

of Pentwyn Mawr and gully sides, the sub-shrubs heather (Calluna vulgaris) and most 

commonly bilberry (Vaccinium myrtillus) begin to make an appearance in the drier acid 

grasslands, while in damper examples, especially in the north and east, cross-leaved heath 

(Erica tetralix) and deer grass (Trichophorum cespitosum) become more evident. However, in 

the areas mapped as acid grassland on Figure 9.2, all the above-mentioned species remain 

very sparse or at best locally frequent in a grass dominated sward. 

9.4.11 On the steepest gully slopes, and often overstood in summer by bracken, there are areas of 

grassland referable to community U4 of the NVC (sheep‟s fescue Festuca ovina – common 

bent Agrostis capillaris – heath bedstraw Galium saxatile grassland). Besides the community 

name-species, tormentil is more common here and sweet vernal grass (Anthoxanthum 

odoratum) and heath grass (Danthonia decumbens) locally common. Other species of this 

more diverse acid grassland present include harebell (Campanula rotundifolia), heath 

woodrush, pill sedge (Carex pilulifera), common dog violet (Viola riviniana) and heath milkwort 

(Polygala vulgaris). There are also occasional individuals of ericoid sub-shrubs scattered 

through the sward, but the structure remains grassland in the areas mapped as such. 

Dry Heath 

9.4.12 Moving towards the summit of Pentwyn Mawr in the north-west of the site, ericoid species 

increase in abundance, eventually becoming more or less constant and, in patches locally 

dominant. This marks a transition from drier acid grasslands through bilberry–wavy hair grass 

heath (community H18) into the Calluna dominated dry heath community H12. The examples 

are degraded however, probably as a consequence of grazing pressure, with the sub-shrubs 

small and stunted and often sparse. Elsewhere, smaller areas of H18 and/or H12, some of 

greater intrinsic quality, if not extent, also occur on the steepest and most inaccessible lower 

slopes of the Dulais and Lliw gullies, particularly on the eastern sides, where they have 

evidently escaped grazing. In all these areas, the main difference between H12 and H18 lies

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in the joint abundance of heather and bilberry in the former. As discussed above, bilberry and 

cross-leaved heath also occur at low abundance in vegetation more clearly referable to acid 

grassland or degraded mire communities. 

Mire Vegetation 

9.4.13 Vegetation referable to the degraded blanket mire community M20, and more particularly the 

species-poor subcommunity M20a, occurs locally on the higher ground, although in many 

areas the transition between this and other vegetation types is very subtle, being demarcated 

by nothing more than an increase in the abundance of the cotton grasses Eriophorum 

vaginatum and E.angustifolium (the former usually dominant). Sphagnum cover, which is 

normally characteristic, can vary from locally frequent to almost entirely absent, with other 

mosses such as Aulocomnium palustre and in particular Campylopus introflexus often far 

more prominent. Other species characteristic of intact mire vegetation are generally sparse or 

absent in these areas. 

9.4.14 The soligenous mire system at the valley head of the Afan Dulais gully is much richer in 

Sphagnum, particularly Sphagnum auriculatum agg., but also with S. fimbriatum and S. 

subnitens, with other bryophytes including Calypogeia muelleriana and Pohlia spp. Localised 

representations of the „bog-pool‟ community M2 are present here. The vegetation here is also 

characterised by large tussocks of soft rush and purple moor grass, both of which are 

abundant elsewhere on the site, but the latter rarely achieves a pronounced tussock form 

elsewhere. Cross-leaved heath is also a characteristic component, but it is never more than 

sparse even here. A further feature of this and other soligenous or valley mire systems on the 

site is the increased prominence of Eriophorum angustifolium, often over E. vaginatum. 

9.4.15 Other much more restricted pockets of valley mire occur along the gully systems of the Afan 

Dulais and Afan Lliw, occurring on small areas of deeper peat on level ground beside the 

stream courses, or as vegetation through which the watercourse passes more diffusely. 

These mires, in some instances approximating to community M21 of the NVC, are the richest 

on the site, with characteristic associates including bog asphodel Narthecium ossifragum, 

marsh violet Viola palustris, cross-leaved heath, bog pondweed (Potamogeton polygonifolius) 

round-leaved sundew Drosera rotundifolia (on exposed peat faces) and bulbous rush Juncus 

bulbosus and the moss Rhynchostegium ripariodes in the channel. Marsh St John‟s wort 

(Hypericum elodes) and marsh pennywort (Hydrocotyle vulgaris) were also recorded here. 

Flushes 

9.4.16 Vegetation indicative of waterlogged ground, seepages or spring lines occurs commonly as a 

diffuse element within other vegetation types throughout the upland habitats on the main wind 

farm site, and, being characterised by the presence of dense stands of soft rush, can form a 

visually prominent component of the site‟s vegetation. The more extensive stands are 

mapped on Figure 9.2. In a few instances, Sphagna are present, sometimes with Eriophorum 

angustifolium, marking a transition towards species-poor representations of M6 mire. 

Other vegetation 

9.4.17 In the lower parts of the Lliw and Dulais ravines or gullies, the steep topography and resultant 

reduction in grazing pressure results in pockets of dry heath vegetation (as described above) 

on the steeper slopes, with more extensive areas on the western slopes in particular 

dominated by bracken (community U20) often in association with U4 grassland. In the more

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humid conditions closer to the watercourses themselves, and especially on rock exposures, 

pteridophyte cover is more characterised by hard fern (Blechnum spicant) with lemon scented 

fern (Oreopteris limbosperma) also present. 

9.4.18 A single „in-bye‟ field on the edge of the common also falls within the red-line area around the 

main wind farm site, being proposed as the location for the substation. This field forms part of 

the Blaen Gerdinen holding, and in common with the rest of that is managed either for silage 

or sheep grazing. The sward is a mixture of improved grassland species such as perennial 

rye-grass Lolium perenne, smooth meadow grass Poa pratensis and white clover Trifolium 

repens but also present and locally frequent are two species indicative of incomplete 

„improvement‟: yellow rattle Rhinathus minor and pignut Conopodium majus. The boundary 

banks retain little or no woody vegetation, but they support fragments of a richer acid 

grassland flora, referable to U4, with sheep‟s fescue, sweet vernal grass, heath bedstraw, 

sheep‟s sorrel (Rumex acetosella) and occasional mouse-ear hawkweed (Pilosella 

officinarum) as well as ferns such as male fern (Dryopteris filix mas), polypody (Polypodium 

sp), maidenhair spleenwort Asplenium trichomanes and black spleenwort Asplenium 

adiantum-nigrum. 

Comparison of Current Habitat Condition with the 1985 Upland Survey and 

Biological Survey of Common Land 

9.4.19 The overall balance of habitats reported in 1985 suggests that at some time in the intervening 

period grazing pressure may have been relaxed, although caution is needed in interpreting 

1985 maps that were reporting complex mosaics with boundaries between slightly different 

heath / grassland mixes recorded according to a different vegetation system. However, the 

1985 summary that “most of the area is dominated by Nardus, Juncus squarrosus and Molinia 

grasslands in a complex mosaic. Grazing is fairly heavy and the Molinia has not developed a 

tussocky form. Small patches of heavily grazed stunted Calluna and Vaccinium myrtillus 

occur on the N and W slopes of Pentwyn Mawr” still provides an accurate description of the 

main elements of vegetation on both the main wind farm site and the common land crossed 

by the access route at Mynydd Garn Fach. 

Exchange Land (Blaen Gerdinen and Blaen yr Olchfa Fach Study Areas) 

9.4.20 Habitat maps for Blaen Gerdinen and Blaen-yr-Olchfa Fach are shown on Figure 9.4. The 

study areas are 8.9ha and 34.2ha respectively. 

9.4.21 Both holdings are farms or former farms on the edge of the moor with small fields separated 

by „cloddiau‟-type earth / stone banks. At Blaen Gerdinen, most of these have lost their 

associated woody vegetation, other than scattered remnants, but at Blaen yr Olchfa the 

majority remain as clear hedgerow features, with hazel a prominent component, along with 

sessile oak, eared willow, hawthorn, blackthorn and rowan, albeit most are neglected and 

grown-out. 

9.4.22 Within these enclosed field units, the grasslands on both holdings have been subject to heavy 

agricultural improvement in the past, presumably in the 1960s to 1980s when substantial 

grants were available for such operations. There is also some evidence of boundary bank 

removal to increase field size, presumably contemporary with the other improvements. Some 

reversion towards semi-natural rush-pasture and acid grassland communities can be 

observed in the northernmost field units at Blaen yr Olchfa, suggesting that attempts at 

improvement here have been abandoned.

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9.4.23 Providing a contrast to these „improved‟ areas of in-bye land, there are small steep valleys 

along the western side of Blaen yr Olchfa, and the eastern side of Blaen Gerdinen which 

contain the upper reaches of streams whose valleys expand downstream. 

9.4.24 The main habitat interest of the Blaen yr Olchfa holding in particular is concentrated in these 

steep valley slopes and streamside areas, with representations of semi-natural vegetation 

including upland heath, mire, ffridd vegetation (mixed acid grassland, bracken and scrub on 

steep slopes), sessile oak and birch woodland with sallow and alder in damper areas 

adjoining the stream, and areas of conifer plantation. Much of the mire vegetation is 

dominated by dense Molinia or has been lost to extensive scrub invasion as a consequence 

of the lack of grazing. 

9.4.25 Mire vegetation can however also be found in association with spring lines and adjoining 

ground and also the stream courses that extend across the northern part of this site, along 

with dense gorse scrub, as well as in small artificial pond-type features in the northernmost 

field. Species associated with these areas include bog pimpernel (Anagallis tenella), star 

sedge (Carex echinata), heath grass (Danthonia decumbens), round leaved sundew, cross 

leaved heath, marsh bedstraw (Galium palustre), marsh pennywort (Hydrocotyle vulgaris), 

marsh St John‟s wort (Hypericum elodes), bog asphodel and bog pondweed (Potamogeton 

polygonifolius) among others. 

9.4.26 The farm complex at Blaen yr Olchfa Fach remains occupied and the stone barns in particular 

offer potential bat roosting sites. 

9.4.27 At Blaen Gerdinen, ecological interest is lower overall and more sparsely distributed, although 

despite the initial impression of wholesale „improvement‟ for agriculture, some of the fields 

managed for silage in rotation with grazing support species such as yellow rattle and pignut in 

a sward otherwise characterised by „improved‟ grassland associates. This includes the field 

identified for the substation. The farmhouse and outbuildings at Blaen Gerdinen are 

completely ruined, with parts only visible as ground traces, and there is little or no scope for 

bat roosting amongst the remnants. Other elements of ecological interest on this site are 

associated with the boundary banks, which support a species-poor representation of U4 

grassland or have sparse associations of fern species such as polypody and black 

spleenwort. Woody vegetation is limited to scattered bushes and, on the southern boundary, 

a hedge mainly of hawthorn. There is also a remnant shelter belt of more mature trees 

including sycamore, ash and rowan around the farmhouse and the end of the lane leading to 

it. 

9.4.28 In the extreme south-east the holding extends onto a small and abandoned field unit on the 

slope of the adjacent valley head. This area is ungrazed and heavily invaded by hazel, birch 

and rowan, with the understorey being a species-poor tussock grassland and rush-pasture. 

The only other area of similar habitat is in the extreme south-west corner of the north-west 

field. Previous surveys suggested the presence of mire vegetation in both of these locations, 

but in 2012 they were noted to support only species-poor soft-rush dominated vegetation. 

Access Route 

9.4.29 The access route contains features that could potentially be ecologically sensitive. Outside 

the numbered points and segments on Figure 9.1 it is understood that no works would be 

needed that could affect ecological features.

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9.4.30 Segment 1 on Figure 9.1 marks the position where the access route would leave the A48. Up 

to this point from the M4, this route would require no works potentially affecting ecology. Two 

alternatives were originally considered from this point; either through a small disused quarry 

(point 2) or uphill through an improved pasture field towards common land. For a combination 

of engineering reasons and potential ecological impacts on regenerating heathland, grassland 

and scrub vegetation and associated fauna in the quarry, use of point 2 was rejected and is 

not considered further. 

9.4.31 The new track (Segment 1 on Figure 9.1) will therefore leave the road using an existing 

gateway but potentially requiring removal of a section of adjoining species-poor hedge 

containing small ash trees that have been assessed to have negligible potential for bats. The 

access road would run coterminous with an existing farm track as it climbs through the field, 

potentially requiring some cut and fill that would affect species-poor improved grassland. It 

would then pass through a relict gateway marked by mature broad-leaved trees (ash and 

horse chestnut), and close to a ruined farmstead with further associated trees, before running 

along the western edge of a second improved grassland field. On the western side of the 

existing track here are further mature broadleaved trees (mainly sessile oak) and a poorlydefined 

hedgerow and fence marking the common boundary. All these trees have been 

assessed for their bat potential and are described under “bats” below. 

9.4.32 This tree belt then peters out into a scrubby fence-line and the proposed access route 

crosses this onto common land at Gopa Hill (Segment 3 on Figure 9.1). It firstly joins the line 

of an existing path that here runs between dense scrub dominated by gorse species, 

hawthorn and young oak. Ground flora vegetation off the line of the path is sparse and 

restricted to small areas of neutral-acid grassland dominated by crested dog‟s tail (Cynosurus 

cristatus), common bent, red fescue and sweet vernal grass (Anthoxanthum odoratum) with 

occasional herbs including tormentil, heath bedstraw and sheep‟s sorrel. 

9.4.33 In segment 4 (as shown on Figure 9.1) the vegetation opens out, being an acid / neutral 

grassland around the path edge passing into bracken fields of varying density. Sweet vernal 

grass is only occasional, the main grass mix being of more strictly neutral grassland species, 

typified by common bent, abundant crested dog‟s-tail and red fescue. However except for 

some white clover near the path, the herbs are more characteristic of acid conditions. None 

are more than occasional but heath bedstraw, mouse-ear hawkweed (Pilosella officinarum), 

sheep‟s sorrel, cat‟s-ear (Hypochaeris radicata) and hawkweed (Hieracium sp.) are all 

present, with foxglove (Digitalis purpurea) near the scrub and bracken edges. Heather is 

present but very sparsely scattered. 

9.4.34 After approximately 250m the proposed route reaches a gate marking the beginning of an 

existing unmetalled but artificially surfaced track that contours round the northern face of 

Gopa Hill, skirting the edge of the common, with improved farmland on the higher ground to 

the south and the steep north-facing scarp of the hill dropping away to the north. For most of 

its length until the tarmac highway is reached this track is cut into the hillside. The verges of 

the track, and the bank on the southern side, support acid grassland with scattered elements 

of heathland (both heather and bilberry) and also shade-tolerant plants such as wood sorrel 

(Oxalis acetosella), dog violet, (Viola riviniana) and male fern (Dryopteris filix-mas). There are 

occasional parts with some enrichment, probably from the use of the track by farm vehicles 

and / or from the improved fields above: typical plants include nettle and creeping thistle. 

There are also small individuals of the invasive alien rhododendron (R. ponticum) as well as 

other shrub species along the track verge.

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9.4.35 The common land north of the track (on the downhill scarp) drops away rapidly and supports 

ffridd-type vegetation, comprised of isolated patches of acid grassland of similar composition 

to those described above set within a dense tangle of scrub and bracken fields, with 

rhododendron, bramble, gorse and the occasional small rowan and birch. The scrub is limited 

in height possibly by weather exposure and forms an impenetrable tangle down to ground 

level on steep and sometimes near-vertical slopes. Occasional patches of fireweed 

(Chamerion angustifolium) are present in gaps. 

9.4.36 Near Cwm Dulais the proposed access route joins the existing metalled road of Heol y Barna 

and then runs coterminous with this across the unenclosed land of Bryn-bach Common. The 

existing carriageway is sunken within low 0.5m banks that support sheep-grazed U4 

grassland transitional to bracken fields or U5 Nardus stands in places. At segment 5 (Figure 

9.1) around 400m 2 of land in staggered strips either side of the road will be affected by 

localised road widening. These strips support a U4-type acid grassland in common with the 

surrounding land, and typified by sheep‟s fescue, common bent, wavy hair-grass, mat grass, 

heath woodrush (Luzula multiflora) and the moss Rhytidiadelphus squarrosus with herbs 

including heath bedstraw, heath milkwort, heath speedwell and sparse bilberry. Bracken and 

soft rush are locally prominent and small plants of rhododendron occur along the roadside 

banks. 

9.4.37 Very similar vegetation is affected at the „fiveways‟ junction at Segment 6 (Figure 9.1) where 

some 750m 2 of land immediately adjoining the existing carriageway will be affected by 

widening works. Again the roadway is set below the surrounding land level and the steeper 

banks adjoining it are less grazed, allowing species such as bilberry and the moss 

Polytrichum formosum to survive alongside early hair-grass (Aira pracecox), heath milkwort, 

tormentil and heath bedstraw amongst the more ubiquitous crested dog‟s-tail, sheep‟s fescue 

and common bent dominated grassland. Again bracken is locally prominent and young 

rhododendron occurs adjoining the road. 

9.4.38 A further area of minor road widening (approximate land take 123m 2 ) is proposed at segment 

7 (Figure 9.1). This affects the southern bank of the road which is quite steep at this location, 

but densely covered by bracken with a shaded out U5 grassland underneath. 

9.4.39 Modifications to the existing carriageway are next required near the isolated dwelling of Henglawd, 

which is passed on a sharp right-hand bend (segment 8 Figure 9.1). Opposite the 

house the grassland on the common here is restricted to species poor mat grass (U5) 

grassland with soft rush patches and some bracken patches very similar to the species-poor 

U5 on much of the main study area. Immediately by the roadside the presence of white clover 

and nettle suggests some enrichment. 

9.4.40 On the house side, the verge is in slightly better condition, with a new wall of traditional 

construction supporting little vegetation itself but with associated foxglove and fragments of 

acid grassland with a fescue-bent composition with heath bedstraw. One tree was identified 

as needing assessment for bat roosting potential, and this was inspected during the specialist 

bat surveys carried out in 2005 (see below). 

9.4.41 At point 9 (Figure 9.1) there would be a need to remove a small area of existing vegetation to 

allow passage around a narrow and very sharp left-hand bend. Here the vegetation is 

predominantly U5 grassland but there is evidence of disturbance from recent highway or 

drainage works. This was associated with additional common species of disturbed ground:

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spear thistle, dandelion (Taraxacum agg.), common mouse ear (Cerastium fontanum), annual 

meadow grass (Poa annua) and ratstail plantain (Plantago major). 

9.4.42 No further modifications to the access route are proposed before the access route leaves the 

existing metalled road near the isolated farmstead of Blaennant Ddu. Here the route will 

exploit a muddy track that angles off towards Mynydd Garn Fach. The track hugs the edge of 

the common for some 750m, running adjacent to field-boundary walls with improved in-bye 

grassland fields beyond, and with steep slopes falling away to the west and north-west. The 

verges of the track support a species-poor MG11 type grassland indicative of agricultural 

improvement and shot through with soft rush dominated flushes indicative of poor drainage. 

This grades downslope to more ffridd-type vegetation. 

9.4.43 After some 750m the track opens out onto the open common of Mynydd Garn Fach. From 

here to the main wind-farm site the track alignment affects species-poor U5 grassland, with 

localised soft rush flushes and small areas of disturbed ground and acid grassland transitional 

to U4 around former mine workings. 

Otter and Water Vole Survey Results 

9.4.44 Potential lying up habitat for otters is present along the main (Afon Lliw) stream corridor but 

such places tend to be in use by sheep taking shelter. Water vole is judged unlikely to use the 

study area on the basis of lack of suitable habitat as well as the lack of any signs found at any 

time during the 2004-2011 period. 

9.4.45 Otters are likely to find poor quality foraging even in the stream courses. However, these form 

corridors that could assist animals dispersing between catchments and occasional use for this 

purpose cannot be ruled out. The chances of catching the evidence of occasional transits 

such as this are small. 

Bat Survey Results 

9.4.46 Bats will forage over high moorland sites similar to Mynydd y Gwair, but such usage tends to 

be intermittent, with likely concentrations in still and warm summer weather coinciding with 

mass insect emergence and flight which bats will commute out of nearby valleys to exploit. 

Catching such events is difficult, and therefore the initial bat activity surveys were designed 

after consultation with CCW to give an overview of the local bat fauna by transect studies that 

concentrated on peripheral areas away from the proposed wind farm itself but where habitat 

structures suggested that bat usage would be more predictable. The transect locations and 

routes for these initial studies are shown on Figure 9.1 and in Appendix 9.2. 

9.4.47 Five species of bat were detected in these original transect studies. They included both 

common and soprano pipistrelles, noctule, brown long-eared and a Myotis 1 species (these 

often cannot be identified further without capture and examination in the hand), affording an 

appreciation of the species composition of bat populations local to the wind farm site. A full 

tabulation of passes by bat species and transect sections is given in Appendix 9.2, along with 

graphic representations of the number of bat passes in each transect section. These show 

that bat activity during the surveys was far from uniform but instead concentrations of 

1 Natterer‟s bat Myotis nattereri has been recorded within 2km of the wind farm site

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particular species occurred in relatively small areas, most often associated with habitat 

interfaces and/or the presence of water. 

9.4.48 Emergence surveys in two areas of former mine-workings on Mynydd Garn Fach (locations 

shown on Figure 9.1 and Appendix 9.3) were also carried out in October 2007 to assess 

whether these represented roost sites close to the proposed wind farm. Bats were found to be 

active in both these locations. At „Mine 1‟ (as labelled on Figure 9.1) a total of 14 passes by 

common pipistrelle, two unidentified pipistrelles, four soprano pipistrelle and one long-eared 

bat / Myotis passed the area feeding or commuting. At „Mine 2‟ only 11 such passes were 

recorded, all by common pipistrelle. No evidence was found that either of these former 

workings were used as roost sites however. 

9.4.49 Additional surveys of bat activity on the main wind farm site were carried out in September 

2009 and May and June 2010. These confirmed low-level use of the wind farm area by bats, 

the principal species involved being common pipistrelle, although possible soprano pipistrelle 

and Natterer‟s bats were also recorded. Higher levels of bat activity were found outside the 

wind farm area in nearby woodland and forestry habitats, consistent with previous 

assessments and survey results. Full reports of these surveys are provided at Appendices 9.4 

and 9.5. 

9.4.50 Overall, the various bat surveys carried out provide a robust base of evidence in support of 

the assessment that bat use of the proposed wind farm site is small-scale, intermittent and 

focused on the more sheltered gullies. Higher levels of activity are only likely to occur as a 

response to a convergence of favourable weather conditions with mass insect emergence 

and flight – e.g. of pyralid moth species feeding on the grasses on the site. Bats will commute 

out of better quality habitats in nearby valleys to exploit such conditions, but even then, use 

levels are likely to be focused in the sheltered gullies, with little use made of the exposed 

moor tops. 

Badger Survey Results 

9.4.51 Open moorland habitats typically provide poor foraging for badgers and where the animals 

are present at all, they typically occur at very low density compared to lowland habitats. 

9.4.52 Prior to 2007, no badger setts were located within the Main Study Area. It was considered at 

that time that use was probably limited to occasional crossing by dispersing animals. In May 

2007, however, badgers were found to have dug into the filling of an old mine shaft or adit 

immediately west of a farm track passing along the west facing slope of Mynydd Garn-Fach. 

As previously observed in such circumstances, there was relatively little spoil excavation (not 

much digging is needed before the remains of the mine chambers are encountered), but hair 

and / or evidence of bedding change were found in three out of six areas of disturbance. The 

other three areas of disturbance appeared to be minor collapses likely to have been triggered 

by the badger activity underground rather than entrances in use by the animals. 

9.4.53 Further badger activity was also noted on the eastern side of Mynydd Garn-Fach during bat 

survey work in October 2007, and this may have been a precursor to a colonisation event that 

resulted in a previously unrecorded sett being found within the redline boundary 

encompassing the main access track route during walkover surveys in early 2010. Field sign 

evidence suggested it was a main sett at the time, and indeed it has remained in continuous 

use since. As this sett appeared to conflict with the access track alignment, further detailed 

work was carried out to ascertain its precise location relative to both the redline boundary and

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to physical constraints such as topography and nearby hydrological systems. The full results 

of this survey are attached at Appendix 9.8. The design response to the emergence of this 

constraint is described later in this section. 

9.4.54 Signs of badger activity have been noted periodically along the route of the access track (for 

example a well-used badger track crosses the route east of segment 4 (Figure 9.1) and 

continues northwards down the steep scarp towards Cwm Dulais), and signs of badger 

activity have been noted in and around the disused quarry at point 2 of the access track. 

However no setts have been found at any point within 30m of the route alignment. 

Reptile Survey Results 

9.4.55 On the basis of sporadic sightings whilst carrying out other fieldwork since 2004, and the 

pattern of background records, common lizard appears to be thinly dispersed over much of 

the upland common land in the area. Sightings have however been concentrated in areas 

where the habitat structure is noticeably less affected by intensive grazing pressure, and 

consequently the species is likely to be scarce at best over both the main wind farm site, and 

the Mynydd Garn Fach sections of access track. 

9.4.56 In addition, slow worms have been found under refugia already present on lower ground 

outside the study area, immediately south-west of the Upper Lliw reservoir dam. This species 

is, however, less likely than common lizard to be making use of the open moorland. 

9.4.57 Suitable habitat for common lizard and / or slowworm also exists virtually throughout segment 

4 of the access route study area (Figure 9.1) and to a lesser extent because of dense scrub in 

segment 3. 

9.4.58 Although the habitats harbouring common lizard are ostensibly also suitable for adder, there 

have been no signs of this species throughout the survey programme, and no background 

records for it have been obtained from SEWBReC for either the application site or the 

surrounding areas of search. 

Amphibian Survey Results 

9.4.59 Although great crested newts are mentioned in the citation document for the proposed 

Pentwyn Mawr and Mynydd Pysgodlyn SINC, no specific location information is given and the 

cSINC covers a very extensive area which encompasses significant portions of land beyond 

the study area boundaries. Conversations with the Swansea County ecologist have not 

yielded the source of this quoted information, and no records for this species for land within 

2km of the main wind farm site, and 500m from the access road route, have been supplied by 

SEWBReC. Against this lack of substantiated records, it is also the case that within or 

immediately adjoining the study area there are, in fact, no water bodies suitable for breeding 

by great crested newt because the only pools are too acid. This has been confirmed by 

repeated observations through the survey programme including specific egg searches in 2004 

and 2005. No habitat changes are apparent up to 2012 that might change this view. 

9.4.60 Other amphibian species able to breed in waters that are too acid to support great crested 

newts include common frog and common toad, both of which have been recorded within the 

study area. Common frog breeding has been confirmed in mire vegetation on the eastern side 

of Mynydd Garn Fach, and the species has been found in other areas of mire vegetation

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associated with the Lliw and Dulais gullies and headwater systems, suggesting breeding 

there. The Upper Lliw reservoir provides a more likely breeding site for common toad. 

Other Mammals 

9.4.61 Foxes have been seen on several occasions, with breeding confirmed in 2008 in an earth dug 

into former mine workings on the north-western side of Mynydd Garn Fach. 

9.4.62 Brown hare has also been observed on the site, albeit sightings have been rare and this 

suggests that the local population is low and/or thinly dispersed. 

Invertebrates 

9.4.63 Invertebrate recording throughout the various studies has generally been in the form of casual 

observations focused on Lepidoptera, Odonata and Orthoptera species. 

Lepidoptera 

9.4.64 Amongst the butterflies, small heath (Coenonympha pamphilus) is widespread and generally 

the most abundant species on the upland areas of Mynydd y Gwair and Mynydd Garn Fach. 

Other less frequently encountered species include meadow brown (Maniola jurtina), 

gatekeeper (Pyronia tithonus) and small white (Pieris brassicae), with clouded yellow (Colias 

croceus), red admiral (Vanessa atalanta), painted lady (Vanessa cardui), small tortoiseshell 

(Aglais urticae) and peacock (Inachis io) present only as transients. Grayling (Hipparchia 

semele) was observed early on in the studies (e.g. 2004) but appears to have disappeared 

from the site in later years, a trend consistent with the national picture of decline for this 

species, and indeed the pattern of local third party records. 

9.4.65 Macro-moth species found on the site up to 2011 have included map-winged swift (Hepialus 

fusconebulosa), mother shipton (Callistege mi) and fox moth (Macrothylacia rubi). All three 

species would be expected here. During habitat survey work in 2011, fox moth was again 

observed, along with oak eggar (Lasiocampa quercus) and (of note) wood tiger (Parasemia 

plantaginis). 

9.4.66 Prior to 2008, the possibility of the scarce moth species double line (Mythimna turca) and 

white-line snout (Schrankia taenialis) was considered and a requirement for further survey to 

rule out their presence discounted on the basis that they do not favour the open grazed areas 

and any possible suitable habitat for breeding within the study area would be confined to the 

valley between the Lliw reservoirs and small sheltered areas in ravines. Although this 

approach was discussed and agreed with the local moth recorder, he subsequently gave 

evidence at the 2010 inquiry to the effect that such surveys should have been carried out. 

9.4.67 In August 2011, a specialist assessment of the site‟s potential value for these and other LBAP 

invertebrates was carried out, the report of which is given at Appendix 9.6. The conclusions 

were that the scope for any of these species to be present was either „nil‟ or „minimal‟. 

9.4.68 22 moth species were recorded as part of this assessment, including two common species 

(garden tiger and small phoenix) that are identified for attention in the national Biodiversity 

Action Plan process but only on a „Research Only‟ basis, to assess whether they are in need 

of further conservation attention.

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Odonata 


9.4.69 Small pools by the main Afon Lliw stream have been noted to support abundant large red 

damselfly (Pyrrhosoma nymphula). Although other Odonata species have been recorded from 

the area by third parties, including old records for black darter, keeled skimmer and golden 

ringed dragonfly, none of these species has been observed on the site by Bioscan during the 

various surveys, and it is likely that any surviving populations are centred on higher quality 

mire and open water habitats downstream and to the south of the wind farm site. 

Orthoptera 

9.4.70 Common green grasshopper Omocestus viridulus is probably the most frequently 

encountered Orthopteran species across the grazed upland areas, with field grasshopper 

Chorthippus brunneus also present. Of note in 2011 was confirmation of the presence of bog 

bush cricket Metrioptera brachyptera in the lower part of the Lliw gully, in a location falling just 

within the application site. There are relatively few other records of this species in South 

Wales and this therefore represents a significant record. 

9.5 Evaluation of the Ecological Resource 

Evaluation Methodology 

9.5.1 An evaluation of the ecological interest of the application site is given below based on the 

application of Ratcliffe‟s criteria (Ratcliffe 1977). Primarily these are size, diversity, 

naturalness, rarity, fragility and typicalness although additional secondary criteria of potential 

value, intrinsic appeal and position within the ecological or geographical unit may be taken 

into account if they make a special contribution to the study area's interest. 

9.5.2 Supplementary to the application of Ratcliffe‟s criteria is the consideration of the legal 

protection and/or conservation status afforded to individual species, or of the collective 

significance of species assemblages. 

9.5.3 Legal protection is defined primarily by reference to the Wildlife and Countryside Act 1981 (as 

amended) and the Conservation of Habitats and Species Regulations 2010 (as amended) 

which implement the European Habitats Directive into UK law. 

9.5.4 Formal conservation status for most species is defined by reference to the red data book 

system 2 or for birds by reference to the red and amber lists of species, as currently set out in 

Eaton et al (2009). Additional attention may also be drawn to species or habitats which are 

the subject of national or local biodiversity action plans drawn up in accordance with the UK 

government's commitments under the 1992 UN Convention on Biological Diversity (the „Rio 

Treaty‟). The Countryside and Rights of Way Act 2000 section 74 (supplemented by the 

Natural Environment and Rural Communities (NERC) Act 2006 section 40) affords a statutory 

basis to the biodiversity action plan (BAP) process, and local planning authorities and other 

government bodies are now required to „have regard‟ to the conservation of biodiversity in the 

exercise of their functions. Species and habitats in Wales that are of „principal importance‟ to 

fulfilling this duty (Species of Principal Importance (SPI) and Habitats of Principal Importance 

2 Following the British Red Data books published by the JNCC/RSNC and the Nationally Notable (Nationally 

Scarce) categorisations recognised by the JNCC

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(HPI) respectively) are set out in lists produced by the Welsh Government pursuant to section 

42 of the NERC Act 2006. 

9.5.5 A local biodiversity action plan (LBAP) for Swansea: “Promoting Swansea’s Natural 

Environment – a local biodiversity strategy and action plan” was published by the City and 

Council of Swansea in April 2005, and has been adopted as Supplementary Planning 

Guidance in support of the Unitary Development Plan (UDP) (Adopted 2008). The LBAP is 

currently undergoing a review by the Swansea Biodiversity Partnership to update actions and 

incorporate new species and habitats declared of principal importance in Wales by the Welsh 

Government since 2005. Contained within the document are a list of species and habitats 

prioritised for conservation action at local (Swansea) level. Certain additional species 

considered to be of importance in a local (in this case County) context are also identified. 

Where such species or habitats occur within the main study area, attention is drawn to them 

in the evaluation below. 

9.5.6 Legal and conservation status are factors material to the assessment of whether a site meets 

the threshold value and criteria for locally important sites in accordance with section 5.5 of 

TAN 5 Nature Conservation and Planning (Welsh Government (2009)). The relevant criteria 

in this context are provided within published guidelines for the selection of non-statutory 

wildlife sites in South Wales (Gwent Wildlife Trust 2004). These have been adopted by the 

Welsh Government and in turn by The City and County of Swansea. 

9.5.7 Context for the assessment of the ecological interest of the application site is provided by the 

survey information for the wider area collected since the inception of the project. This allows a 

high degree of confidence to be attached to assessments of comparative value against the 

wider local resource. 

Evaluation of Peat Resource 

9.5.8 The peat studies carried out since 2010 confirm that certain areas of the site would appear to 

support „significant‟ peat deposits, defined here (in response to comments received from 

CCW since 2008) as those in excess of 300mm in depth. 

9.5.9 Putting aside the intrinsic value of peat as an effectively irreplaceable resource, and the role it 

plays in archaeological or paleo-ecological preservation, the two principal ways in which peat 

resources are valued in ecological or quasi-ecological contexts are in terms of its role as a 

carbon store, and for the biodiversity value of associated vegetation. 

9.5.10 The importance of the on-site peat resources in carbon sequestration terms is assessed in 

Appendix 4.1 of this ES. In terms of biodiversity, the vegetation associated with the peat 

deposits within the application site is low in quality. Edge of range effects do not sufficiently 

explain the degraded nature of the vegetation, and therefore one or more negative 

anthropogenic influences is likely to be the key driver in the site‟s relative paucity of habitat 

and botanical interest – the most immediately apparent as having been implicated being 

overgrazing. Such degradation means that the common situation that deeper peat correlates 

with a significantly elevated level of habitat interest does not necessarily apply at Mynydd y 

Gwair. In most cases, the transition to vegetation of surrounding areas on shallower (e.g. 

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Evaluation of Habitats 


9.5.11 Both the main wind farm site, and the land proposed for the new access track across Mynydd 

Garn Fach, are dominated by species-poor upland communities of acid grassland, with 

localised representations of degraded heath and mire within the wind farm site itself. Although 

they cover a large area, these habitats are poor in species and are relatively damaged (and 

hence, unnatural), derivatives of more diverse mire vegetation that is likely to have historically 

been the dominant cover over the study area. 

9.5.12 It is considered that the species-poor acid grasslands that predominate both on the wind farm 

site and on Mynydd Garn Fach are of no more than immediate local (i.e. site-wide) value, 

given the preponderance of the habitat type throughout the upland areas of the locality. It is 

also assessed that they would not qualify under the Welsh Government adopted criteria for 

designating Local Wildlife Sites in Wales. This is despite more or less the entirety of the 

common land within the application site being identified by the City and County of Swansea 

for inclusion within SINC boundaries - principally the Pentwyn Mawr and Mynydd Pysgodlyn 

candidate SINC. 

9.5.13 The areas of degraded heath and mire vegetation might marginally qualify as “degraded 

areas with some potential for recovery”, but this is contingent on that potential being there. 

Encouragingly, some recovery would appear to have taken place in the upland heath 

component, at least in the 27 years since 1985. This is consistent with the checklist provided 

by the Council in support of the cSINC – it is these types of habitat that have been identified 

as conforming to local BAP categorisations, not the extensive areas of species-poor Nardus 

grassland. Collectively these do represent a resource of County (i.e. Swansea) value, in part 

because the blanket mires, though degraded, represent edge-of-range examples of the type. 

9.5.14 The small, more intact, mires within the gullies of both the Dulais and Lliw headwater 

systems, as well as the other more extensive examples outside the main wind farm site (but 

within the wider area studied since 2004), including within the Common Land exchange area 

at Blaen yr Olchfa would, by contrast, more clearly qualify as intact or largely intact mire 

habitats or degraded ones that still show some remaining distinctive features of the habitat 

types. These habitats are judged to be of County (e.g. Swansea) value in the context of their 

relative scarcity in the immediate local area, and because they support scarce species (e.g. 

bog bush cricket and oblong-leaved sundew). 

9.5.15 The holdings at Blaen Gerdinen and Blaen-yr-Olchfa Fach are dominated by agricultural 

grasslands that have been subject to past improvement and, in the context of such habitats 

being abundant locally and on a wider scale, they are of very limited biodiversity value, 

despite the presence (at Blaen Gerdinen) of a very few species of more interest such as 

yellow rattle and pignut. However, the traditional boundary networks, especially where a bank 

is combined with a hedge, are nonetheless small and degraded examples of a local and 

national BAP habitat and therefore of value on the immediate local scale. The mire remnants 

at Blaen-yr-Olchfa Fach, while also small and partly degraded, are better examples of a BAP 

habitat and contain some species rich areas. These are of moderate value on the local (here 

County) scale. 

9.5.16 The access route connecting the wind farm site to the A48 at Pontarddulais mainly exploits 

existing metalled roads, tracks surfaced with unbound hardcore or paths and tracks worn bare 

by frequent pedestrian and/or vehicular traffic. Where new track is proposed, the main habitat 

affected is species-poor acid grassland (on Mynydd Garn Fach), although there are much

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smaller areas of improved grassland, scrub, mature trees, acid grassland, bracken-dominated 

vegetation and dry heath affected where widening or upgrade works will be necessary. Even 

for the more semi-natural components of these habitats, the small scale of the areas affected 

means that their value, if considered in isolation, is low and at no point measurable above 

immediate local level. 

9.5.17 Although individual vascular plant species of local interest (e.g. round-leaved sundew) were 

found in association with some of the above habitats (as referred to in the text above), no 

scarce, rare or protected species of flora have been found within the application site at any 

stage. 

Evaluation of non-avian fauna 

9.5.18 Comparison of the 2009 and 2010 bat survey data for the wind farm site itself with the earlier 

surveys of plantation edges and other habitats surrounding the site confirms that the value of 

the site as a foraging area for bats (all European protected species) is low, with such use that 

is made of the area concentrated not surprisingly on the sheltered Lliw and Dulais gullies with 

their stream courses. With no roosting opportunities present within the site itself, bats using 

these features evidently commute into the area from roosts situated in surrounding, more 

optimal habitats - the most likely commuting routes are along the stream courses and into the 

wind farm site from the south. Little or no evidence of commuting or foraging activity across 

the exposed summits and watersheds was found, consistent with expectations. Usage of 

peripheral areas is typical of the upland fringes, with five species found altogether, and of 

these the two more commonly encountered pipistrelle species being the most abundant. 

9.5.19 Along the proposed access road alignment, better quality habitat for bats is available in 

places (except on open areas of common such as Mynydd Garn Fach). Evidence of a 

pipistrelle roost was found in the porch of the isolated house at Hen Glawdd, and trees with 

potential for bat roosting are present in association with the common boundary and an 

abandoned farmstead at the lowest section of the route near Pontarddulais. No roosts have 

however been found in these trees despite inspections in both 2007 and 2010. 

9.5.20 An active badger sett (protected under the Badgers Act 1992) is present in old mine-workings 

on the alignment of the proposed access route across Mynydd Garn Fach, but the upland 

areas in general, and the wind farm site in particular, are of relatively low value to this species 

in comparison with the surrounding valleys. Although present in local river systems, the wind 

farm site is of low to negligible value to otters (European protected species), although it may 

receive occasional use for transit between river catchments, and it provides highly suboptimal 

habitat for water voles (protected under the Wildlife and Countryside Act 1981 (as amended)). 

9.5.21 Reptile species require attention because of their partly protected status under the Wildlife 

and Countryside Act and because both common lizard and slow worm were recorded in 

habitats at the southern edge of the main wind farm site in the early phases of the baseline 

studies. Both these species are national Biodiversity Action Plan species and Species of 

Principal Importance in Wales. Although there have been no subsequent sightings, despite ad 

hoc searches of suitable habitats and extant refugia, these two species may be present at low 

to very low densities across the upland habitats of the main wind farm site, although in many 

areas the poor structural diversity of the habitats may militate against this. In terms of 

ecological value, the presence of common lizard is not unusual in upland situations and both 

species are known to be present and locally common in other areas of Swansea county. The 

study area is therefore unlikely to be a local or wider stronghold for either species.

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9.5.22 Although not subject to any statutory nature conservation protection, brown hare does have a 

species action plan under the national and local BAP and it is a Species of Principal 

Importance in Wales. However, very few sightings of this species have been made over the 

2004-2012 period and therefore use of the study area by this species is evidently very low. 

9.5.23 Due to significant national declines in recent years, grayling butterfly was added to the list of 

priority species under the UK BAP in 2007, is a Species of Principal Importance in Wales and 

is on the Red List of threatened butterflies. As confirmed by background records, this species 

could formerly have been expected to be present throughout the upland habitats of the 

locality, but although recorded by Bioscan in 2004, there have been no subsequent sightings, 

reflecting a national trend towards declining population and range contraction. 

9.5.24 Invertebrate faunas of degraded moorland and acid grassland tend to be of low diversity, with 

even the commoner species of interest restricted to those pockets with a more diverse habitat 

structure. The picture on the proposed wind farm site and on Mynydd Garn Fach appears 

consistent with this, with generally only a very restricted number of species observed, and a 

general absence of the specialist species that tend to be of higher conservation significance. 

Bog bush cricket was however recorded (a singing male) in mire habitats in the southern part 

of the Afan Lliw gully during 2011. The only other records for this species in Swansea appear 

to relate to the Gower, and therefore confirmation of its presence on Mynydd y Gwair is 

probably of county significance. 

Likely future in the absence of development 

9.5.25 In the absence of the proposed development, there is no reason to suppose that the land 

within the application site would not continue under the same land uses (i.e. either as grazed 

common or improved agricultural land). While there is an increasing political climate and 

mechanisms available for improving grazing regimes and other management for biodiversity, 

the uptake of such schemes and their results are difficult to predict in any particular place. A 

particular problem on the main wind farm site is the diversity of interested parties that would 

need to be brought together into a consensus to enable any agri-environment scheme to 

work. The likelihood of significant habitat management changes occurring is therefore 

assessed as low. 

9.5.26 In terms of the habitats and vegetation, the most likely result of this would be a degree of 

continued but slight recovery in the degraded upland habitats on the site in response to an 

apparent (but not confirmed) reduction in grazing pressure. The proposed development, 

except in the small areas used for turbine foundations and ancillary works, would not preclude 

any such recovery or indeed the imposition of any particular management regime on the 

upland commons. Accordingly the future of the habitats and flora on the site without 

development (i.e. under the status quo) is taken to be effectively the same (except for hard 

developed areas) as if the proposed development took place. 

9.5.27 Such recovery of vegetation and a consequent improvement in the diversity and conservation 

value of the upland habitats could translate to increased use of the upland areas by key 

species of conservation value. Depending on the degree of recovery, increased use by 

species such as common lizard and brown hare might be a long term proposition.

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Design Mitigation 


9.5.28 This section identifies aspects of the currently proposed scheme that have come into being as 

a direct or indirect design response to minimise or avoid ecological impacts. In some 

instances, reduction of ecological impact has been the sole purpose of design changes. In 

others, design measures have been adopted as a response to multiple environmental factors, 

and the reduction in ecological impact arising is part of a wider suite of benefits. 

9.5.29 The site design and layout has evolved over a period of 8 years, and the outputs from both 

engineering and environmental studies have fed into this process. A full description of the site 

design process can be found in Chapter 3 Site Selection and Design Evolution and is shown 

in the Site Evolution Diagrams (Figures 3.2a to 3.2e). In terms of ecological effects, the main 

relevant changes over time are as follows. 

9.5.30 The overall size and footprint of the Application Site has contracted significantly from 650Ha 

to 471.5Ha since it was initially considered in 2004, mainly as a result of the withdrawal of 

initial proposals to site turbines on Mynydd Garn-Fach and the exclusion of land around Banc 

Maestir-mawr from further consideration. Although a number of environmental factors 

influenced this choice, the result is a significant stand off from the habitat corridor of the lower 

Lliw Valley and associated features assessed as important as a commuting conduit for 

wildlife, including raptors such as goshawk and bats. 

9.5.31 Further changes to the design have been made since 2008 in response to detailed peat depth 

studies to avoid siting wind farm infrastructure on peat of even relatively shallow depth 

wherever possible. This has resulted in the number of turbines being reduced from 19 to 16, 

and the internal service track layout being re-configured to avoid deeper peat deposits 

wherever it is possible to do so. Where deposits in excess of 300mm depth cannot be 

avoided, floating track construction will be used to retain the peat resource in-situ. 

9.5.32 Regularly used and well tested measures have also been adopted, as set out in Chapter 11 

(Hydrology and Hydrogeology) to preclude any impact via changed drainage patterns or water 

chemistry to mire fragments within the Dulais and Lliw gullies, or indeed habitats associated 

with these watercourses downstream of the study area (including the Upper Lliw Reservoir). 

These include locating all turbine foundations, tracks, cabling and other ancillary equipment a 

minimum of 20m from ravine and gully habitats and associated mires and flushes. This has 

resulted in avoidance of the need for tracks or other features to cross gullies or significant 

watercourses. Drainage from tracks will be collected in track-side ditches designed to reduce 

water velocity and to filter out suspended sediments through being vegetated. 

9.5.33 The close proximity of the proposed wind farm to existing power lines, and the location of the 

substation has minimised the length of underground cabling required between the turbines 

and the substation and underground cable connection to onsite grid. The precise connection 

point to the existing lines has been located to the south of the old steading at 

Blaenffynhonnau in order to avoid any impact on the old field system or associated stream 

and mire vegetation there. 

9.5.34 The access route has likewise been chosen to minimise additional works required to the local 

road system that might have adverse effects on ecology. Where such works are inevitable, 

new routes have been chosen to avoid semi-natural habitats on common land as far as 

possible, for instance on Gopa Hill where existing farm tracks are exploited, and to avoid 

specific features such as trees containing structures with potential for bat roosts. The route,

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as described in Chapter 11 (Hydrology and Hydrogeology) has also been chosen to avoid the 

need for new bridgeworks that might risk impacts on (for instance) otter passage or bat 

roosts. A design amendment has been employed to maintain a minimum 30m stand-off 

between the main badger sett on Mynydd Garn Fach and the access route alignment. 

9.5.35 Finally, the substation has been placed in a field that has been subject to past improvement 

and is of low biodiversity value. The bank section requiring removal for its access is likewise 

degraded and of little value. These design measures have avoided any significant impact 

from the substation. 

9.5.36 Likewise, the transfer of the remaining holdings at Blaen Gerdinen, and the holdings at Blaen 

yr Olchfa Fach to common land has no negative implications for the conservation value of the 

grasslands present there - indeed there is likely to be an attendant reduction in intensive 

management that should see, over time, a reversion from improved grasslands dominated by 

ubiquitous broad-tolerance species, to acid grasslands more akin to those of the open 

common, as well as a reversion to more natural drainage patterns through neglect. Transfer 

might even bring more indirect benefits in the increased availability of grant aid for 

maintenance and / or restoration of the surviving boundary systems and mire areas. 

9.6 Assessment of Impacts 

Methodology 

9.6.1 The assessment methodology follows as far as possible the guidelines produced for 

ecological impact assessment by the Institute for Ecology and Environmental Management 

(IEEM 2006). The approach taken is set out below: 

Identification of Key Receptors 

9.6.2 The key ecological receptors are identified from the baseline information amassed from desk 

and field surveys. The decision as to which ecological receptors are „key‟ in this context is to 

some extent a value judgement, informed by factors such as national and local conservation 

status and legal protection. The current IEEM guidance recognises that professional 

judgement and a certain level of subjectivity is unavoidable when apportioning value to 

individual ecological receptors. However certain parameters and points of reference can be 

used to help ensure consistency – these are discussed below: 

9.6.3 Sites already possessing statutory or non-statutory nature conservation designations will have 

been subjected to some form of evaluation process in the past, and their importance defined 

at a geographical scale (e.g. international, national, local). For these, evaluation will generally 

reaffirm their qualifying attributes, or in some cases may identify where designation may no 

longer be appropriate. 

9.6.4 Factors such as extent, naturalness, rarity, fragility and diversity are all relevant to the 

determination of ecological value, and for the evaluation of sites and habitat features outside 

designated sites, these and other criteria as described by Ratcliffe (1977), may be applied. 

Ratcliffe‟s criteria are integral to the procedure for selecting both Sites of Special Scientific 

Interest and many non-statutory designation systems in the UK, and therefore remain an 

accepted standard for site evaluation.

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9.6.5 In applying these criteria, attention may be drawn to the relative scarcity or abundance of 

features within the survey area and in the wider geographical context. Some criteria are 

however absolute and not relative to scale. Ancient woodland, for example, is fragile 

irrespective of whether it is being considered in an international or local context. Similarly, the 

value of an otherwise poor habitat may be elevated if it is central to the survival of a rare 

species. 

9.6.6 Where evaluation is important for the purposes of informing decisions related to land-use 

planning and development control, the above approach needs to be supplemented by 

consideration of whether individual species are subject to legal protection3, or whether 

habitats or species are present which have been identified as „priorities‟ for biodiversity 

conservation in the UK4. Planning authorities have a statutory duty5 to further biodiversity 

objectives and the presence of such resources may therefore be material to the determination 

of development control decisions (Anon, 2005). 

9.6.7 Finally, attention may be drawn to species not necessarily subject to legal protection or 

identified by Government as a priority for biodiversity conservation, but which nonetheless 

have an „unfavourable‟ conservation status as defined by the Red Data Book system 6 or the 

Red and Amber lists for birds (Gregory et al. 2002), or which are otherwise known to be rare 

or scarce in a local or regional context. 

9.6.8 Scales of comparison varying from the international to the context of the local area may be 

used to define the measure of importance attached to individual features. The definition of 

geographic terms can vary, but in this evaluation the following geographic frame of reference, 

as contained within the current Institute of Ecology and Environmental Management (IEEM) 

guidelines (IEEM 2006), is used. This allocates importance at the following scales: 

International; 

UK; 

National (i.e. England/NI/Scotland/Wales); 

Regional; 

County, 

District; 

Parish; and 

Immediate local (within zone of influence only - i.e. the application site) 

3 

Principal legislation being the Wildlife and Countryside Act 1981 (as amended) and the Conservation (Natural 

Habitats &) Regulations 1994 (as amended) which implement the EC Habitats Directive. Some animals are 

protected under separate legislation (e.g. the Protection of Badgers Act 1992). 

4 

Biodiversity: The UK Action Plan (1994) Command 2428 and subsequent Habitat and Species Action Plans. 

5 

Further to section 74 of the Countryside and Rights of Way Act 2000, and section 41 of the Natural Environment 

and Rural Communities Act 2006. 

6 

Following the British Red Data books published by the JNCC/RSNC and the Nationally Notable (Nationally 

Scarce) categorisations recognised by the JNCC

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Determining the Sensitivity of Key Receptors 


9.6.9 In order to determine whether an individual effect on a key ecological receptor is „significant‟, 

the sensitivity of the affected habitat, site or species must be considered. The sensitivity of an 

individual receptor is a product of various factors including: 

habitat extent or population size (at a given geographical level) 

habitat or population fragility (including ability to recover) 

the rarity of a species or habitat; and 

susceptibility to environmental change (e.g. from disturbance or pollution). 

9.6.10 Applying the above criteria, sensitivity of individual receptors can be classified as follows: 

Table 9.2 Sensitivity 

Sensitivity Habitat Example Species example 

High 

Medium 

Habitat is highly susceptible to nutrient 

enrichment or invasion from competitive 

species 

Habitat has highly specialised hydrological or 

soil/geology requirements (e.g. calcareous 

fen) 

Habitat is present as small and isolated 

fragments vulnerable to edge effects 

Habitat takes an extended period to develop 

full suite of components (e.g. ancient 

woodland) 

Habitat can tolerate some elevated levels of 

pollution or will recover within a shortmedium 

term (e.g.

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Sensitivity Habitat Example Species example 

Low 

Habitat is highly resistant to nutrient 

enrichment or other forms of pollution and 

physical disturbance (e.g. improved 

grassland) 

Habitat has non-specific requirements that 

are readily met elsewhere 

Habitat is extensive and well able to 

accommodate localised or more extensive 

damage 

Habitat is easily recreated over a short 

timescale (e.g. improved grassland) 

Species is highly resistant to 

disturbance and pollution (e.g. most 

urban wildlife) 

Species‟ population is widespread 

and recolonisation in the wake of 

any localised range reduction likely 

to occur readily 

Species has high recruitment rates 

likely to lead to rapid recovery of 

population levels 

9.6.11 A certain amount of subjectivity and the application of professional judgment is unavoidable 

when determining sensitivity, however in addition to firsthand experience of the 

species/habitat and locality in question, a wealth of scientific literature and/or local 

conservation status information can often be drawn upon to inform such judgements. 

Impact Magnitude 

9.6.12 The following terms in Table 9.3 are used to quantify the „magnitude‟ of identified impacts in 

this assessment: 

Table 9.3 Impact Magnitude 

Impact Magnitude Definition 

Very High 

High 

Moderate 

Minor 

Negligible 

Significance of Effects 

An example of a very high magnitude impact would be direct mortality or 

displacement of a significant proportion of a species‟ population or loss of 

habitat at a level likely to remove its continued representation at the given 

geographical level being considered. 

An example of a high magnitude impact would be direct mortality, indirect 

displacement or habitat loss that would be likely to substantially reduce the 

population level or degree of representation at the given geographical level 

being considered. 

Moderate impacts include those likely to result in a net reduction of 

population or habitat representation (at least in the absence of effective 

mitigation or compensation) at the given geographical level being 

considered 

Minor impacts include those that may result in loss of a few individuals from 

a species‟ population or minor reduction in habitat extent at the given 

geographical level being considered. 

Negligible impacts are those that are not likely to give rise to measurable 

effects on population level or habitat representation at the given 

geographical scale. 

9.6.13 Whether a potential effect is „significant‟ or not at the given geographical level that the 

receptor is valued at, is determined by quantifying the magnitude of effect on each of the

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receptors identified. Thus for receptors of national or international value and high sensitivity, 

negative effects measured at high or very high magnitude are likely to represent a significant 

impact at that geographical level. At the other end of the scale, minor magnitude effects on 

receptors of low sensitivity and only immediate local value are likely to be below significance 

thresholds. Substantial effects on high value receptors that are of low sensitivity may fall 

either side of the significance threshold - in such cases mitigation may be able to be 

employed to ameliorate effects. A key consideration is whether the „integrity‟ of a site or 

ecosystem (e.g. its coherence of structure and function) and/or the „conservation status‟ of a 

species or habitat (e.g. the ability of a population/habitat to maintain itself at pre-development 

levels/quality) will be compromised. 

Cumulative impacts 

9.6.14 Cumulative or „in combination‟ effects on ecological resources have been assessed through 

obtaining where possible details of impact assessments for other consented, operational or „in 

planning‟ wind farm projects within the region. The process is unavoidably constrained by the 

availability of such information, which may be withheld on grounds of commercial sensitivity, 

and factors such as the degree to which other assessments have followed standard guidance 

– older impact assessments often contain no baseline survey data for bats for example. Such 

situations necessitate a degree of subjective application of professional judgement where 

necessary to address information shortfalls. Where this approach has been necessary, this is 

indicated and confidence predictions (see below) attributed accordingly. 

Impact Prediction Confidence 

9.6.15 For all impacts identified, confidence levels in this assessment are attributed based on the 

following criteria in Table 9.4 (as taken from IEEM 2006): 

Table 9.4 Impact Prediction Confidence 

Confidence Level Definition 

Certain/near certain Probability estimated at 95% chance or higher 

Probable Probability estimated above 50% but below 95% 

Unlikely Probability estimated above 5% but below 50% 

Extremely unlikely Probability estimated at less than 5% 

Key Receptors 

9.6.16 In terms of assessing the significance of ecological impacts arising from the proposed wind 

farm at Mynydd y Gwair, the following key receptors have been identified:

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Table 9.5 Key Receptors (Non-avian) 

Scale Key Receptors 


International None. The site is not subject to any international designation and no species are 

present either on-site or within the zone of potential influence in populations that could 

be considered to be important at international level. 

National None. The site is not subject to any national designation and no species are present 

either on-site or within the zone of potential influence in populations that could be 

considered to be important at national level. 

Regional / 

County 

1. Mynydd Psygodlyn and Pentwyn Mawr candidate SINC. The site forms part of the 

area proposed to be designated, although it does not contain representations of all the 

cited interest features. 

2. Peat resource. The deposits on-site represent a significant proportion of the 

Swansea county resource. 

3. Intact / species-rich soligenous/valley mires. Although small individually, the 

collective resource is measurable at County level 

4. Degraded blanket mire. Although impoverished and consequently of low inherent 

value compared with wider representations, the areas of degraded blanket mire on 

site are „edge of range‟ examples, lending an elevated degree of intrinsic interest. 

5. Dry-heath. Again the examples on the site are impoverished and consequently of 

low inherent value compared with wider representations, including within Swansea. 

6. Bog bush cricket. The apparent presence of an outlier population in the lower Lliw 

gully represents one of very few confirmed localities for this species in the South 

Wales region. 

District/Parish 1. Bats – only very low numbers of common species confirmed as using the site. 

2. Reptiles – very sparse populations of common lizard at best 

3. Locally uncommon plant species (e.g. round leaved sundew) 

Immediate 

local (i.e. site) 

Impact Sources 

Direct Impact Sources 

1. Acid grassland 

2. Improved and semi-improved grasslands 

3. Small areas of scrub/ffridd and mature trees (access route) 

4. Mammals other than bats (including badgers and brown hare). 

5. Invertebrates (other than bog bush cricket) 

9.6.17 Possible sources for direct effects on ecological resources from the proposed wind farm 

include the following construction activities: 

Construction of 16 wind turbines including related base-slab construction and the 

appropriation of additional areas for lay-down, assembly areas and contractors‟ facilities. 

Topsoil layers, including shallow (i.e.

P a g e | 160 


Construction of control building and substation compound at Blaen Gerdinen. 

Localised works of vegetation removal and excavation associated with widening existing 

metalled roads and or upgrading existing tracks or paths along the access route 

connecting the site to the A48 at Pontarddulais. 

Indirect Impact Sources 

9.6.18 Possible indirect effects on habitats are essentially limited to temporary dust deposition or 

localised disruption to soil water levels affecting vegetation close to access tracks or 

construction areas together with the potential for watercourses and ditch systems to be 

affected by increased silt loads arising from areas disturbed by construction operations. 

Similar effects could also arise from any de-watering operations connected with excavations 

for piling and base-slab construction. In the long term, changes in vegetation could arise from 

alteration to substrate and other effects occasioned by the new track network and platform 

areas beneath turbines. 

9.6.19 The principal secondary impact source for non-avian fauna relates to the potential for bats to 

collide with wind turbines. There is also the potential for the presence of turbines (and 

associated factors such as shadow flicker and any perceived change in the „openness‟ of the 

site) to lead to effective displacement of site use by higher fauna through avoidance 

behaviour. 

Construction Phase 

9.6.20 The potential for significant effects on habitat resources from the siting of turbines, access 

roads and other wind farm components has been minimised by confining such features 

wherever possible to degraded examples of upland vegetation that are assessed as of value 

only on the immediate local scale. Even where affecting areas that might be considered to 

meet the definitions contained within the local Biodiversity Action Plans for heath, acid 

grassland and other habitats, the area of such habitats affected is small, both in absolute and 

relative terms. A proportion of this landtake is expected to be temporary, lasting only for the 

duration of the construction phase, and thereby giving rise to short-term impacts. Whilst the 

remainder is a long term impact, only reversing once the wind farm site has been 

decommissioned and restored, it is minor in magnitude and in the context of the limited value 

of the habitats, not of significance at anything above the immediate local (i.e. site-wide) scale. 

The integrity of the Pentwyn Mawr and Mynydd Psygodlyn proposed Site of Importance for 

Nature Conservation, if adopted, would not be compromised by the presence of the wind farm 

(confidence: certain). 

9.6.21 Similarly, amendments to the design mean that areas of peat deposits greater than 300mm in 

depth are only affected in a handful of areas, and here they will be retained in-situ through 

use of „floating track‟ construction techniques. The total volume of peat excavated during the 

construction phase has therefore been restricted to approximately 20,000m3. As detailed in 

the Draft Construction Management Plan (Appendix 4.2) the entirety of this will be re-used in 

restoration on site. Because some loss of peat is likely to be inevitable as a consequence of 

this disruption, predicted impacts on this County value resource fall within the „moderate‟ 

category of magnitude. Confidence in this prediction is tempered by the possibility of such 

losses being compensated to some degree over the long term by recovery of peat forming 

processes in areas „re-wetted‟ (e.g. as a consequence of track alignments locally intercepting 

current erosion gullies) Because of such uncertainties as to the magnitude of any negative

P a g e | 161 


effect over the long term, confidence in the impact predictions in terms of the peat resource is 

set at „probable‟. 

9.6.22 Despite the restricted extent of the above-described habitat losses in comparison with the 

wider on-site and local resource, there remains the possibility, in the absence of applied 

mitigation, for impacts on fauna that are subject to legal protection. In respect of non-avian 

fauna, the access route alignment conflicts with an active badger sett and there is evidence of 

a diffuse population of relatively common but partly protected (from killing or injury) reptile 

species across at least parts of the upland area. In terms of the loss of available habitat for 

such species, there is no scope for impacts of anything above negligible magnitude in terms 

of local or wider populations, but the legal protection afforded to individual animals of these 

species requires that mitigation measures are taken, as detailed under „Mitigation‟ below. 

9.6.23 Direct impacts from access improvements for construction (i.e. along the access route 

between Mynydd Garn Fach and the A48) have also been restricted to habitats of low (i.e. 

immediate local) value and in all cases the landtake is minor in magnitude and too small in 

extent to give rise to habitat loss impacts of significance at any higher than immediate local 

(i.e. site) level. However measures to ensure legal compliance are required in respect of one 

area where a narrow gap between trees with potential for bat roosting has to be negotiated by 

the access route within the area identified as segment 3.on Figure 9.1. Bats typically use tree 

structures on an intermittent basis, so the worst case has to be assumed even if there is no 

evidence of roosting at the time of the baseline surveys. It is therefore proposed to offset the 

loss of bat roosting opportunities at this location by the provision of bat boxes on retained 

trees regardless of the lack of any evidence of a bat roosting issue here. . 

9.6.24 Control of emissions to air and water during construction, including potential runoff and 

pollution of watercourses, requires strict control for wider environmental as well as ecological 

reasons. These potential impacts, and the controls to minimise their risk, are described in 

Chapter 11 (Hydrology and Hydrogeology), and there is no need for mitigation over and 

above measures described there. 

9.6.25 Certain habitats on and downstream of the site depend for their maintenance on the current 

water regime, including its pH. In particular, the use of calcareous stone in access tracks 

could give rise to indirect impacts. However, as set out in Chapter 4 Project Details and 

Construction the use of calcareous material will be avoided for supply reasons even before 

ecological and any other considerations are taken into account. Accordingly no significant 

impact is likely from this source. 

Operational Phase 

9.6.26 During the operation of the wind farm the extent of habitat loss is expected to progressively 

reduce from that associated with the construction phase as a consequence of habitat 

recovery, in particular in areas used only on a temporary basis but also after re-instatement of 

soils (including peat) and associated vegetation along track shoulders and around turbines. 

Thus, there will be no additional direct impacts from land take on fauna or flora, post 

construction. 

9.6.27 The potential for air or water pollution from emissions or disturbance from maintenance or 

repair operations would be subject to the same strict controls as during the construction 

period (see Chapter 4, Project Details and Construction).These should be adequate to avoid 

the risk of significant impacts to ecology. No further mitigation is required for such impacts.

P a g e | 162 


9.6.28 Access controls in the form of locked gates and ditches will be employed to discourage any 

increase in inappropriate vehicular access to the common occasioned by the construction of 

the access road and internal service tracks. Successful prevention of unsanctioned use of the 

track network should ensure incidents are no more common than they are at present. 

9.6.29 The main sources of potential impacts on receptors from the operating wind farm therefore 

concern the potential effects of turbines on aerial fauna. Birds are dealt with in Chapter 10 

(Avian) and bats are addressed below. 

9.6.30 In general, wind farms on upland sites such as Mynydd y Gwair have a lower potential to 

have significant effects on resident bat populations than wind farms sited in other habitats in 

Britain by simple virtue of the more limited usage of such upland habitats by bats. The bat 

surveys carried out support this view, with bat activity generally concentrated in habitats at the 

periphery of the Main Study Area (and well away from the wind farm site). 

9.6.31 Bats may be more likely to traverse across upland areas when making post-breeding 

migratory movements. Studies in the US (e.g. Keeley et al 2001, Higgins et al 2007) have 

indicated that it is when undertaking such movements that bats may be particularly 

susceptible to collision with wind turbines, and post construction monitoring by Bioscan at a 

lowland wind farm site (Coldham in Cambridgeshire) also found collision fatalities of bats to 

be concentrated in the late summer period which is consistent with post-breeding migratory 

movements. 

9.6.32 The UK bat fauna does not include any species associated with the types of mass migration 

notable amongst some species in the United States. Smaller scale migrations evidently occur, 

but the available evidence suggests this is likely to be focused on features such as river 

valleys. In the US, wind farms sited on or near forested ridges have caused the largest 

fatalities of bats associated with migratory movements. At Mynydd y Gwair there are no such 

conditions: the local forestry does not extend over ridge tops in the wind farm area. 

9.6.33 The evidence from the baseline studies and from experience elsewhere therefore suggests 

that the risk of bat fatalities arising from collisions with the proposed wind turbines at Mynydd 

y Gwair is intrinsically low, and furthermore that the risk of any collision fatalities having 

population-level consequences for any of the species confirmed as using the site is negligible 

(confidence: near certain). 

9.6.34 No significant effects on other fauna, including open country species such as brown hare, and 

uncommon or scarce invertebrates, are anticipated during the operational phase. 

9.7 Mitigation and Monitoring 

Construction Phase Mitigation 

9.7.1 Appropriate mitigation measures to reduce the magnitude of identified effects on protected 

species and other ecological resources are contained within the draft Construction Method 

Statement submitted at Appendix 4.2. The full detail will be subject to agreement with the 

planning authority and relevant consultees at the post-consent stage, and as informed by any 

further monitoring studies recommended, but the main measures to reduce ecological 

impacts over and above those taken as part of the design process are as follows: 

Any works to trees affected or potentially affected by the access route construction works

P a g e | 163 


at Bolgoed-uchaf will only be carried out after further full inspections for bat roosts by 

licensed ecologists. If no evidence of current or recent roosting is found at the time, then 

felling can proceed without further action. Should a roost be discovered, then any bats will 

require exclusion prior to works under the terms of a Welsh Government license required 

separately from planning consent. In respect of the requirements of the licensing process, 

the need for construction access is overriding (Chapter 4 Project Details and 

Construction), the route has been chosen to minimise ecological impacts over 

alternatives and the detailed design has sought to minimise tree loss over possible 

alternatives that would require more trees to be affected. 

The linear nature of wind farm construction and associated habitat disturbance means 

that any attempt to wholly exclude and remove reptiles from the construction area prior to 

commencement would be impractical and most likely unsuccessful. Instead, all affected 

areas will be mown prior to the start of construction and arisings removed. Mowing will 

take place either at times of year when reptiles are dormant (e.g. winter) or in suitably 

warm conditions during the active season, to minimise the scope for that operation to 

itself impact on individual animals. The effect of mowing will be to make the area (other 

than the fringes likely to be used for basking) relatively unattractive to reptiles (as well as 

nesting birds). The mown areas will be stripped of vegetation during the reptile activity 

season to allow any animals still present on these fringes to escape. 

A comprehensive approach will be taken to mitigation of impacts on peat resources 

including use of floating track construction wherever peat deposits of >300mm have been 

identified from peat depth surveys, as well as special handling and storage measures for 

excavated peat and re-use of all peat resources on the site in restoration and habitat 

creation. 

Appointment of a Project Ecologist and Project Hydrologist to assist with construction 

phase surveys, monitoring and mitigation. The project ecologist‟s role will extend to 

briefing contractors working near the identified badger sett and monitoring to ensure no 

significant impact on this or any other protected species. 

9.7.2 The overall effect of these additional measures on ecological resources is taken into account 

in the assessment of residual impacts below. 

Assessment of Residual Impacts on non-avian ecology 

Construction 

9.7.3 Impacts on habitats and peat resources, including habitats potentially subject to local or 

national BAP initiatives, and forming part of the supporting interest of the Pentwyn Mawr and 

Mynydd Pysgodlyn candidate SINC, from small-scale habitat loss and potential for localised 

changes as a consequence of the wind farm construction are assessed as not significant on 

any geographical scale above the immediate confines of the site. No scarce, rare or protected 

plant species are at risk. 

9.7.4 In terms of protected fauna, the potential for bat roosts to be affected has been restricted by 

design and other mitigation to the need for works on a single tree. Compensation through the 

provision of artificial roost sites (bat boxes) equivalent to or exceeding the quantum of 

roosting opportunities lost is well tested as a compensation technique and there is no 

significant likelihood of the conservation status of any bat species being threatened, even in

P a g e | 164 


the event that the additional pre-commencement surveys referred to above indicate a change 

of circumstances that requires licensed mitigation measures to be adopted. The low level of 

bat use of this open upland site with its degraded habitat examples minimises the potential for 

significant effects from collision or displacement, both in terms of resident bat populations and 

any transient migratory movements. Residual impacts on bats are therefore assessed as not 

significant at any geographical scale. 

9.7.5 Impacts on habitats and peat resources, including habitats potentially subject to local or 

national BAP initiatives, and forming part of the supporting interest of the Pentwyn Mawr and 

Mynydd Pysgodlyn candidate SINC, from small-scale habitat loss and potential for localised 

changes as a consequence of the wind farm construction are assessed as not significant on 

any geographical scale above the immediate confines of the site. No scarce, rare or protected 

plant species are at risk. 

9.7.6 In terms of protected fauna, the potential for bat roosts to be affected has been restricted by 

design and other mitigation to the need for works on a single tree. Compensation through the 

provision of artificial roost sites (bat boxes) equivalent to or exceeding the quantum of 

roosting opportunities lost is well tested as a compensation technique and there is no 

significant likelihood of the conservation status of any bat species being threatened, even in 

the event that the additional pre-commencement surveys referred to above indicate a change 

of circumstances that requires licensed mitigation measures to be adopted. The low level of 

bat use of this open upland site with its degraded habitat examples minimises the potential for 

significant effects from collision or displacement, both in terms of resident bat populations and 

any transient migratory movements. Residual impacts on bats are therefore assessed as not 

significant at any geographical scale. 

9.7.7 Exclusion by habitat manipulation will remove the great majority of risk of any reptiles being 

harmed during construction. On the linear scale employed there is always a small risk of 

inadvertent harm to individuals even when full best practice precautions are employed. Soon 

after construction, any such impact would be compensated by habitat recovery and/or the 

additional habitat features associated with tracks and turbine bases. In the worst case the 

resulting minor magnitude impact would be significant on the immediately local scale, 

reducing within a few years to not significant. 

9.7.8 Similar conclusions can be drawn for all other non-avian species of note, including Species of 

Principal Importance such as brown hare, and the more uncommon invertebrate species 

present. 

9.7.9 Table 9.6 below provides a summary of the predicted impacts of the construction of the wind 

farm on non-avian ecological receptors, and their significance, both before and after 

mitigation is applied.

Impact 

Source 

P a g e | 165 

Table 9.6 Impact Summary – Non-avian Receptors (Construction Phase) 

DIRECT IMPACTS 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Receptor 

Mynydd 

Pysgodlyn 

and Pentwyn 

Mawr 

candidate 

SINC 

Peat 

resources 

Intact / 

species-rich 

soligenous 

and valley 

mires 

Degraded 

blanket mire. 

Value 

County 

County 

County 

County 

Sensitivity 

(to impact 

source) 

Predicted Effect 

Low Direct removal of 

contributing habitats 

(c.20ha of designated 

1874ha) 

Moderate 

Moderate-high 

Moderate-high 

Excavation of c20,000m 3 

of peat for access tracks, 

turbine bases etc 

Loss of c.2700m 2 of poor 

quality valley-head mire 

due to floating track 

construction. Other 

examples avoided. 

Loss of c. 1.7ha ha of 

impoverished M20a 

vegetation (approx 4% of 

on-site resource) 

Significance 

of Effect 

without 

Mitigation 


Mitigation / 

compensation 

Not significant None required. 

Significant 

impact at 

County level 

Impacts 

potentially 

significant at 

site level only 

Impacts 

potentially 



due to low 

quality of 

vegetation 

Peat will be stored 

and re-used in 

restoration. Floating 

track used where 

deposits >300mm. 

Shoulders of track 

will be dressed with 

peat to assist 

recovery of 

vegetation. Track 

may have beneficial 

„blocking‟ effect on 

hydrological 

patterns in areas 

affected by 

drainage 

Shoulders/cutslopes 

of tracks will 

be dressed with 

peat to assist 

recovery of 

vegetation. Track 

may have localised 

beneficial effect on 

Residual 

Impact 

No significant 

effect 

Not significant 

above site 

level 


above site 

level 


above site 

level 

Confidence 

Level 

Certain 

Probable 

Near certain 

Near certain

Impact 

Source 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

P a g e | 166 

Receptor 

Dry heath 

vegetation 

Bog Bush 

Cricket 

Bats 

(common 

pipistrelle, 

soprano 

pipistrelle, 

noctule, 

brown longeared 

bat, 

Myotis spp cf 

Natterer‟s) 

Reptiles 

(common 

lizard, slow 

worm) 

Locally 

uncommon 

Value 

County 

Regional 

District/Parish 



Sensitivity 

(to impact 

source) 

Moderate 

High 

Low 

Low 

Moderate-high 


Loss of c. 0.5 ha of 

impoverished H18/H12 

vegetation (approx 3% of 

on-site resource) 

None – site for cricket 

remote from construction 

works 

Negligible loss/alteration 

in poor quality foraging 

habitat availability. No 

roosts found in affected 

mature trees 

Minor magnitude 

loss/alteration of habitat 

availability. 

All stations remote from 

construction works 

Significance 

of Effect 

without 

Mitigation 

Impacts 

potentially 



due to low 

quality of 

vegetation 

No effect 

predicted 



No effect 

predicted 


Mitigation / 


hydrological 

patterns 




mineral soils to 

assist recovery of 

vegetation 

Residual 

Impact 


above site 

level 

Confidence 

Level 

Certain 

None required None Certain 

None required, 

although further 

confirmatory 

surveys of affected 

trees will be 

undertaken 

Habitat 

manipulation and 

displacement 

employed to reduce 

risk to individual 

animals 

Not significant Certain 


None required None Certain

Impact 

Source 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

Permanent 

and 

temporary 

landtake for 

construction 

P a g e | 167 

Receptor 

plant species 

(e.g. roundleaved 

sundew) 

Acid 

grasslands 

Improved 

and semiimproved 

grasslands 

Scrub/ffridd 

and mature 

trees along 

access route 

Mammals 

other than 

bats 

(badger, 

brown hare) 

Invertebrates 

(other than 

bog bush 

cricket) 

Value 

Immediate 

local 

Immediate 

local 

Immediate 

local 

Immediate 

local 

Immediate 

local 

Sensitivity 

(to impact 

source) 

Low 


Very minor loss in 

comparison with wider 

resource 

Significance 

of Effect 

without 

Mitigation 



Mitigation / 





mineral soils to 

assist recovery of 

vegetation 

Residual 

Impact 

Confidence 

Level 


Low Negligible Not significant None required Not significant Certain 

Low 

Negligible in context of 

wider resource 

Low Minor magnitude effect 

on badgers through 

disturbance 

Low 

Minor magnitude 

loss/alteration of habitat 

availability. 



None required, but 

bat boxes will be 

provided on 

retained trees at 

Bolgoed uchaf in 

any event 

Minimum 30m 

stand-off employed 


Not significant Near certain 

Not significant None required Not significant Certain

Impact 

Source 

P a g e | 168 

Receptor 

INDIRECT IMPACTS 

Indirect 

effects (dust, 

pollution) 

Indirect 

effects 

(hydrological 

change) 

Mynydd 

Pysgodlyn 

and Pentwyn 

Mawr 

candidate 

SINC 

Intact / 

species-rich 

soligenous 

and valley 

mires 

Degraded 

blanket mire. 

Peat 

resources 

Intact / 

species-rich 

soligenous 

and valley 

mires 

Degraded 

blanket mire. 

Value 

County 

County 

Sensitivity 

(to impact 

source) 

Low 

Moderate-high 


Potential for mobilised 

peat, mineral soils and 

hydrocarbons from 

construction plant to 

affect local watercourses 

substantially reduced by 

scheme design, but 

remains a theoretical 

impact source 

Localised change to 

hydrology causing 

indirect peat losses 

(through drying) in areas 

adjoining construction 

sites 

Significance 

of Effect 

without 

Mitigation 

Potential for 

significant 

effects up to 

County level if 

downstream 

mire and 

headwater 

systems 

deleteriously 

affected. 

Potential for 

significant 

effects is 

reduced by 

layout design 

and structure 

of on-site peat. 

Site 

observations 

indicate 

hydrological 

effects on peat 

adjoining 

excavated 

areas likely to 

be restricted to 

300mm) 

deposits to avoid 

disrupting 

hydrological 

systems. 

Compaction 

beneath trackways 

may address 

localised existing 

problems of peat 

drying. 

Residual 

Impact 

Minor 

magnitude 

effects 

localised to the 

immediate 

environs of 

construction 

works (e.g. 

within 10m). 


above site 

level. 

Residual 

negative 

effects of 

minor 

magnitude and 

localised to the 

immediate 

environs of 

construction 

works (e.g. 

Impact 

Source 

Indirect 


hydrological 

change, 

pollution) 

Indirect 

effects 

(hydrological 

change, 

pollution) 

Indirect 


hydrological 

change, 

pollution) 

P a g e | 169 

Receptor 

Dry heath 

vegetation 

Locally 

uncommon 

plant species 

(e.g. roundleaved 

sundew) 

Acid 

grasslands 

Improved 

and semiimproved 

grasslands 

Scrub/ffridd 

and mature 

trees along 

access route 

Value 

County 


Immediate 

local 

Sensitivity 

(to impact 

source) 

Low-moderate 

Moderate-high 

Low 


Potential for very 

localised effects from 

dust/pollution close to 

construction areas 

Potential for mobilised 

peat, mineral soils and 

hydrocarbons from 

construction plant to 

affect stations of such 

plants substantially 

reduced by scheme 

design, but remains a 

theoretical impact source 

Potential for very 

localised effects from 

dust/pollution close to 

construction areas 

Significance 

of Effect 

without 

Mitigation 

Impacts 

potentially 



due to low 

quality of 

vegetation 

Potential for 

population 

depletions 

significant up 

to 


level if 

downstream 

mire and 

headwater 

systems 

deleteriously 

affected. 



Mitigation / 


Detailed 

hydrological, silt 

and pollution 

management 

systems form part 

of Construction 

Management Plan 

Detailed 


and pollution 

management 




Detailed 


and pollution 

management 




Residual 

Impact 


above site 

level 

Confidence 

Level 

Certain 

Not significant Near-certain 


Indirect Bbadger, Minor magnitude effect Not significant Minimum 30m Not significant Near certain

Impact 

Source 

effects 

(disturbance) 

P a g e | 170 

Receptor 

brown hare, 

other nonavian 

fauna 

Value 

Immediate 

local 

Sensitivity 

(to impact 

source) 

Low 


on badgers. No 

significant effect on 

brown hare or any other 

fauna 

Significance 

of Effect 

without 

Mitigation 


Mitigation / 


stand-off from 

badger setts 

employed 

Residual 

Impact 

Confidence 

Level

P a g e | 171 

Operation 


9.7.10 No significant operational phase impact on bats is predicted due to the site‟s character and 

location, which is assessed as likely to preclude significant use either by resident populations 

or during migratory periods. 

9.7.11 No other significant operational phase impacts on non-avian ecological receptors are 

predicted. 

9.7.12 Table 9.6 below provides a summary of the predicted impacts of the operational phase of the 

wind farm on non-avian ecological receptors, and their significance, both before and after 

mitigation is applied.

Impact 

Source 

P a g e | 172 

Table 9.6 Impact Summary – Non-avian Receptors (operational Phase) 

Receptor 

OPERATIONAL PHASE 

Collision with 

wind 

turbines 

Disturbance 

(from 

presence of 

turbines and 

periodic 

maintenance 

activity) 

Bats 

Badgers, 

brown hare 

Value 


Immediate 

local 

Sensitivity 

(to impact 

source) 

Low 

Low 


Due to low levels of site 

use by bats, and the 

flight habits of the 

species involved, any 

collisions likely to be very 

rare and not significant in 

terms of local population 

levels and background 

mortality rates. 

Minor magnitude effect 

on badgers. No 

significant effect on 

brown hare or any other 

fauna 

Significance of 

Effect without 

Mitigation 

Mitigation / 



Residual Impact 

Confidence 

Level 

Not significant None required. Not significant. Near-certain. 


Minimum 30m 

stand-off from 

badger setts 

employed 

Not significant Near certain

P a g e | 173 

Cumulative Impacts 


9.7.13 The proposed wind farm at Mynydd y Gwair is understood to be the first such proposal of its 

scale for the City and County of Swansea. As such, it is not possible to consider cumulative 

impacts at the County level simply by reference to other wind farm projects within the same 

administrative area. 

9.7.14 However, a wind farm is under construction to the north of the site on land at Mynydd y 

Betws, over the County boundary in Camarthenshire. The location of this wind farm relative to 

Mynydd y Gwair is shown at Figure 6.9 of this ES. 

9.7.15 In order to assess the cumulative effect of these two proposed wind farms and the 

significance of any such effects, the ES for the Mynydd y Betws proposal was obtained and 

reviewed. 

9.7.16 The Mynydd y Betws site is essentially a similar area of upland, although with more varied 

topography and a preponderance of north-west facing slopes. The uniformity of habitats that 

is such a striking characteristic of Mynydd y Gwair is also less apparent at Mynydd y Betws, 

which appears to contain a more diverse suite of vegetation types including both wet and dry 

heath together with blanket bog. 

9.7.17 The extent of likely habitat loss or disruption proposed at the Mynydd y Betws site appears 

broadly comparable to that at Mynydd y Gwair. Relative to habitat features of interest, there 

are however subtle differences in the siting of the turbines and (in particular) the access track 

network, and these suggest that impacts on habitats and vegetation of marginally more value 

are likely at Mynydd y Betws, in large part due to stream crossings, the excavation of borrow 

pits for construction and less intensive efforts to avoid deeper peat deposits. At Mynydd y 

Gwair careful access track design has enabled any new stream crossings to be avoided and 

borrow pits are also not proposed. 

9.7.18 However, in common with wind farm sites generally, the extent of habitat loss likely to arise 

from the proposed Mynydd y Betws wind farm is relatively modest, and in combination with 

such effects at Mynydd y Gwair, the cumulative effect is not considered to be significant at 

any geographical level above the immediate context of the two sites. 

9.7.19 Impacts on (non-avian) protected fauna at Mynydd y Betws also appear to be minimal, 

although no bat survey work was carried out at that site in line with scoping responses from 

CCW. 

9.7.20 The cumulative effect of both wind farms on birds is assessed in Chapter 10 (Avian Ecology). 

Impact Summary 

9.7.21 The wind farm scheme represents the culmination of an iterative process of site selection and 

design which, over time, has seen a significant contraction in both the extent of the 

development area and number of turbines proposed within it. The process has seen a 

corresponding reduction in the inherent scope for ecological effects, with the current scheme 

the least likely to give rise to significant impacts. 

9.7.22 Informing that process has been a wealth of ecological information from studies in and around 

the wind farm site since 2004. A very high level of understanding of baseline conditions has

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been achieved, with habitats and vegetation classified, mapped and evaluated and a wealth 

of survey information amassed for birds (Chapter 10 Avian Ecology), badgers, bats, water 

voles, otters and invertebrates in particular. 

9.7.23 The proposed wind farm site sits within an extensive swathe of upland habitats much in 

keeping with the surrounding area. Remnant and in some instances potentially recovering 

examples of heath and mire communities are present, but in general these occur only as 

degraded fragments or diffuse examples amongst acid grassland of restricted value and 

diversity, itself reflective of high grazing intensity and an absence of blanket peat. This 

featureless aspect and fairly monotypic habitat structure harbours not only an impoverished 

breeding bird community dominated by a very few common species (see Chapter 10 Avian 

Ecology), but also does not appear to be of particular value to the local populations of any 

other species of fauna or flora. 

9.7.24 The site has no statutory nature conservation designation, although it is contained within an 

extensive „candidate‟ non-statutory Site of Importance for Nature Conservation identified by 

the City and County of Swansea. The wind farm affects only a very small part of this 

„proposed‟ designation, and does not impinge on any high quality examples of the key habitat 

features of interest mentioned in the draft citation. 

9.7.25 By far the greatest scope for the wind farm to give rise to impacts on non-avian ecological 

resources is during construction. There will be temporary and (smaller-scale) permanent 

losses of habitats during the construction of the 16 turbines, and the interlinking access tracks 

and cable routes. Localised habitat losses will also occur along the road network used to 

access the site, and the construction of a sub-station and grid connection will necessitate 

minor additional land take. Compensation land has been identified that will be „exchanged‟ as 

new open access common land, but in any event the losses of habitat occasioned by these 

activities are restricted and affect resources of limited value that are well represented in the 

locality. With the adoption of strict codes of working in respect of peat resources and site 

drainage, direct habitat losses or indirect habitat damage during construction will be of minor 

magnitude, and such effects are not predicted to be significant at any geographical scale 

above the immediate confines of the development boundary. 

9.7.26 Mitigation measures, including appropriately timed removal of vegetation in advance of 

construction, are proposed to counter the potential for construction phase effects on reptiles 

and nesting birds that could generate issues of legal compliance, even if not significant in 

terms of these species‟ local or wider conservation status. Indirect disturbance of upland 

fauna may also occur during construction, potentially resulting in temporary displacement of 

certain species from affected areas, however the extent of habitat in the upland area is ample 

to accommodate any temporary displacement without giving rise to significant effects and in 

any event no highly sensitive species occur on the wind farm site. 

9.7.27 The main scope for post-construction or operational effects relates to the possibility of longerterm 

displacement and/or collision risk effects on aerial fauna, principally birds and bats. Birds 

are addressed in Chapter 10 (Avian Ecology). In respect of bats, a number of common bat 

species occur in the surrounding area, where habitats are better suited to them, but use of the 

site by these populations is at a much reduced scale and in particular activity in the exposed 

areas of airspace where turbine rotors will operate is evidently minimal, in keeping with the 

exposed and featureless nature of the terrain. No significant risk to the conservation status of 

either local or wider bat populations has therefore been identified.

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9.7.28 Cumulative impacts have been assessed with specific reference to the wind farm under 

construction nearby at Mynydd y Betws. Despite a rather more diverse habitat assemblage at 

that site, and factors such as the use of borrow pits there, the extent of overall habitat loss 

likely to arise from construction of the Mynydd y Betws wind farm is not dissimilar to that of 

the Mynydd y Gwair proposal. In the context of local availability of such habitats, the 

cumulative effect is not therefore considered to be significant at any geographical level above 

the immediate context of the two sites. The in-combination effects of the two wind farms on 

avian fauna are assessed in Chapter 10. In respect of non-avian protected fauna they are 

assessed as likely to be minimal, although in respect of bats the degree of certainty attached 

to this assessment is reduced by the fact that no bat survey work was carried out at that site. 

9.8 References 

Avery, B.W. (1980). Soil Classification for England and Wales (Higher Categories). Soil 

Survey Technical Monograph No 14. 

Gwent Wildlife Trust (2004) „Guidelines for the Selection of Wildlife Sites in South Wales‟. 

HMSO (1994) „Biodiversity – the UK Action Plan‟. 

IEEM. (2006). „Guidelines for ecological impact assessment in the United Kingdom‟(Version 7 

July 2006) 

Jones (et al) 2010. Assessing the Impact of Windfarm Developments on Peatlands in Wales. 

CCW Guidance Note 14 th January 2010. 

NCC (1990). A Handbook for Phase 1 Habitat Survey: A technique for Environmental Audit.

Mynydd y Gwair Wind Farm - RWE.com

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