Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Afon Claerwen Hydro Scheme

Preliminary Ecological Appraisal

September 2017 Version no.2

Report prepared by: Laura Cottrell MSc BSc (Hons) Neil Parker CEnv MCIEEM

Environment Systems Ltd. 9 Cefn Llan Science Park Aberystwyth Ceredigion SY23 3AH

Tel: +44 (0)1970 626688 www.envsys.co.uk

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Executive Summary

Environment Systems was commissioned by Elan Hydro Ltd to undertake a desk study and habitat survey to support a proposed 1.1 MW hydro scheme in the Elan Valley, on the Afon Claerwen.

The aims of the study were to assess the nature conservation value of the survey area, the likely presence of rare or protected and notable species, and to identify any features, habitats or species, which could constrain the development. Mitigation and enhancement measures are also discussed, where relevant.

The site comprises areas of semi-natural woodland, marshy grassland, heathland, modified wet bog, improved and semi-improved acid grassland. The site is surrounded by broadleaved woodland, acid grassland, heathland and agricultural land with associated hedgerows. The habitats are suitable to support protected and notable species but with use of appropriate and sensitive design measures, it is considered that the potential for impact on these species can be avoided and mitigated.

The intake and approximately 1.2 km of the pipeline lie within a Site of Special Scientific Impact and Special Protection Area. There will be a small loss (0.17 ha) of modified wet bog. Given the small area, amounting to less than 0.01%, of the overall SSSI, SAC and SPA that the loss will not impact on the integrity of the wider qualifying features. It will therefore be necessary to engage the local planning authority and Natural Resources Wales to consider the need to screen the development proposals for Habitat Regulations Assessment as well as agree the mitigation options identified. Information relating to the sites and the screening for the Habitat Regulations Assessment is provided in Section 5 of this report.

Provided the measures identified in this report are developed into construction method statements/plans the effects of the development on ecological receptors will be largely mitigated and will avoid significant ecological effects.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Table of Contents

1. Introduction ...... 1 Development Description ...... 1 Objectives of the Study ...... 1 2. Methodology ...... 3 Desk Study ...... 3 Field Survey ...... 3 Limitations ...... 4 3. Results ...... 5 Statutory Designated Sites ...... 5 Protected and Priority Species ...... 6 Extended Phase 1 Habitat ...... 7 Protected and Priority Species ...... 10 4. Development Aspects with Potential for Significant Ecological Effects ...... 11 Construction Aspects ...... 11 Operational Aspects ...... 11 5. Habitat Regulations Assessment – Screening Information ...... 12 Elenydd-Mallaen SPA ...... 14 Elan Valley Woods SAC ...... 16 Elenydd SAC ...... 18 6. Discussion ...... 19 Designated Sites ...... 19 Invertebrates ...... 22 Reptiles ...... 22 Birds ...... 23 Otter & Water Vole ...... 23 Badger ...... 24 Bats ...... 25 Other Notable Species ...... 25 7. Conclusion ...... 26 8. References ...... 27 Figures ...... 29 Figure Series 1 – Designated Sites Plan ...... 29 Figure Series 2 – Phase 1 Habitat Map ...... 29 Appendix A – Layout Drawings ...... 30 Appendix B –BIS Protected Species Results ...... 31 Appendix B – Phase 1 Habitat Survey Target Notes and Species List ...... 34 Appendix C – Photographic Plates ...... 35 Appendix D – Dust Management Plan Information ...... 49 Appendix E – Twyi and Claerwen Invertebrate Survey: Technical Note...... 50 Appendix F – Grassland/Heath Extraction and Restoration Method ...... 51

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Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

1. Introduction

Environment Systems was commissioned to undertake ecological survey to support the development design, planning submission and consenting for a hydro-electric scheme operating on the Afon Claerwen in the Elan Valley.

Development Description The development is located approximately 10 km southwest of Rhayader (National Grid Reference SN 89553 61784) between the Claerwen and Caban-coch reservoirs. The development is a run-of- river hydro-electric scheme with a capacity of 1.1 MW. Electricity will be generated by abstracting water from a location approximately 1.7 km downstream of the Claerwen Dam. A proportion of the flow (which has already been agreed and licenced by Natural Resources Wales) will be abstracted from the river and fed through either a pipe approximately 1.8 m in diameter or twin smaller (1.2 m) pipes. The pipe(s) will be laid underground and the alignment will broadly follow the southern side of the unmade track for approximately 2 km at which point it will return to the river via a hydro- electric turbine.

The turbine will be housed in a small building with dimensions of approximately 10 m x 8 m. In addition to the turbine house there will be a second building and compound containing electrical switchgear and transformer allowing connection to the Distribution Network Operator's (DNO) substation. Both buildings will be cladded in appropriate local materials. Power will be exported along an underground cable to be owned and operated by the local DNO. There will be no requirement for overhead lines. The power house and DNO substation will be located in an improved grassland field as shown in the layout drawings provided in Appendix A – Layout Drawings. Access to this location will be made available by making improvements to an existing track including some realignment) which falls from the public highway road. The existing track is well used by off-road vehicles. This access route will remain after the construction work is complete to allow future vehicle access to the turbine house and transformer compound.

Construction works are intended to take place during the spring and summer period and are expected to extend to between six and nine months. Plant and machinery used will include small numbers of excavators, concrete mixers and standard HGVs. It is anticipated that no more than two abnormal loads will be in operation during the construction period. During the laying of the pipeline an excavation corridor of approximately 200 m in length would be operation at any one time. The average depth of the excavation is likely to be 2.8 or 2.2 m (maximum diameter of single or twin pipes plus 1 m cover) subject to the ground contours. Temporary French drains will be provided to divert surface water away from the excavation. The total construction corridor, including the areas identified for the temporary deposition of spoil and turves, could be up to approximately 40 m in width.

Objectives of the Study As the development has the potential to affect sensitive ecological receptors such as habitats and protected species, it was deemed necessary to undertake a Preliminary Ecological Appraisal (PEA) to help guide the design evolution and assess potential negative and positive effects. The objectives of the study were therefore:

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

• Carry out an ecological desk study to obtain records of designated sites and protected species held by third parties; • Undertake a field survey to determine habitats present on-site; • Undertake a field survey to identify any habitats or features suitable to support protected or priority species; • Prepare an initial assessment of the likely effects on identified ecological receptors; • Define the scope of the required Ecological Impact Assessment (EcIA) to input into an Environmental Statement (ES) for the wider Environmental Impact Assessment (EIA); and • To make recommendations for further survey, assessment and/ or mitigation measures.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

2. Methodology

Desk Study A desk study was completed to identify statutory and non-statutory designated sites, and any known protected or priority species, within 2 km of the development.

The Biodiversity Information Service for Powys and Brecon Beacons National Park (BIS) was consulted to provide records of protected and priority species within 2 km of the site boundary. In addition, the Multi-Agency Geographic Information for the Countryside (MAGIC) website was consulted alongside publicly available datasets provided by National Resource Wales (NRW), to identify statutory designated sites and priority habitats within 2 km of the development.

The UK Biodiversity Action Plan (BAP) website was consulted to determine whether species and habitats identified (by both the desk study and the field survey) on and around the site are subject to specific action plans either under the UKBAP or Local BAP.

Field Survey The survey area was defined to encompass the development site including:

• 40m construction zone either side on the pipeline and additional access tracks; • Intake weir, intake chamber and construction compound • 40m construction zone around cut back rock escarpment to intake area • Main site and powerhouse construction compound • Buried tailrace and discharge to river • Construction access route • Indicative cable route from the powerhouse to the power houses at northeast of Caban-coch reservoir near the Elan Valley Visitor Centre.

2.2.1. Extended Phase 1 Habitat Survey An extended Phase 1 Habitat Survey (JNCC, 1993 as amended) was conducted throughout the survey area. Phase 1 Habitat Survey is a standard technique for rapidly obtaining baseline ecological information over a large area of land. It is primarily a mapping technique and uses a standard set of habitat definitions for classifying areas of land on the basis of the vegetation present. For this survey, the technique was modified (or extended) to provide more detail over a smaller area and give further consideration to fauna. The standard habitat definitions were used.

The dominant and readily identified higher plant species from each habitat type within the survey area were recorded and their abundance was assessed on the DAFOR scale:

• D - Dominant • A - Abundant • F - Frequent • O - Occasional • R - Rare

These scores represent the abundance within the defined area only and do not reflect national or regional abundances. Plant species nomenclature follows Rose (2006).

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Incidental records and field signs of fauna were also made during the survey. Habitats identified were evaluated for their potential to support protected species and other species of conservation concern, including Biodiversity Action Plan Priority Species. Effort was made to search for field signs of protected species considered likely to be present in the area based on the desk study results. This included searching all watercourses within the survey area for signs of otter and water vole, assessing all trees and structures for presence of raptor nests and bats and searching areas of dense undergrowth, hedgerow and woodland for signs of badgers.

A search was also made for evidence of the presence of invasive plant species listed on Schedule 9 of the Wildlife & Countryside Act 1981 as they are subject to strict legal control.

The surveys were undertaken by Laura Cottrell MSC BSc (Hons) and Neil Parker CEnv MCIEEM on the 24th & 30th May 2017, who have a combined experience of 20 years in ecological survey and assessment.

Limitations The species data collated during the desk study is mainly derived from records submitted by members of the public and ad hoc surveys undertaken by volunteers. Therefore, it should not be considered as a definitive list of the protected species and other species of conservation concern that occur in the local area.

The Phase 1 Habitat survey was conducted at an optimal time of the year. No limitations are therefore foreseen in terms of vegetation identification.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

3. Results

Statutory Designated Sites

3.1.1. Elenydd-Mallaen SPA The development is located partly within the Elenydd-Mallaen Special Protection Area (SPA). The site covers an area of 30,022 ha and is qualified for its breeding season populations of peregrine Falco peregrinus (1.3% of UK population), red kite (9.4% of UK population) and merlin Falco columbarius (0.5% of UK population). Habitats that support these breeding raptor species are found in the Elan Valley Woods SAC and Elenydd SAC & SSSI.

The location of the Elenydd-Mallaen SPA, as well as all other described below, in relation to the development is shown in Figure Series 1 – Designated Sites Plan.

3.1.2. Elan Valley Woods SAC The Elan Valley Woods Special Area of Conservation (SAC) covers an area of 438.74 ha with the nearest stand of woodland situated approximately 260 m north from the pipeline route. The qualifying features for the SAC are the presence of old sessile oak woods (91A0). The habitat supports a rich invertebrate fauna, in addition to plant assemblages and fungi. Notable local species of bryophyte include Bazzania trilobita, Plagiochila Spinulosa and Saccogyna viticulosa, which are accompanied by the lichen species Arthonia vinosa, Catillera sphaeroides and Thelotrema lepadinium. The habitat additionally serves to facilitate breeding red kites Milvus Milvus. The available information from JNCC estimates the primary qualifying feature, old sessile oak woods, covers approximately 288.25 ha. European dry heaths (4030; 33.78 ha) and Tilio-Acerion forests of slopes, screes and ravines (9180; 7.02 ha) are qualifying features but not a primary reason for SAC selection.

3.1.3. Elenydd SAC The Elenydd SAC covers approximately 8581 ha. The boundaries of the SAC are over 500m east of the development at its nearest point. Calaminarian grassland of the Violetalia calaminariae (6130; 25.83 ha) is present as a result of heavy metal extraction at Cwm Ystwyth, which has facilitated the colonisation of a number of scarce heavy metal-tolerant species. Vezdaea cobria, Lecanora handelii, Gyalidea subscutellaris and Ditrichum plumbicola are species of lichens and bryophytes that are responding positively to the habitat. Blanket bogs (7130; 3331.72 ha) are also a primary reason for SAC selection and Elenydd is considered to hold the largest tract of blanket mire in the uplands of central Wales. Active blanket bogs in the area are considered a priority feature. Oligotrophic to mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or of the Isoeto- Nanojunctea (3130; 60.26 ha) and European dry heaths (4030; 404.63 ha) habitats are present but not a primary reason for SAC selection. Floating water plantain Luronium natans (1831) is known to be present in the upland lakes of the Elenydd as they have been relatively unaffected by natural systems modification (e.g. abstraction etc.).

3.1.4. Elenydd SSSI The Elenydd Site of Special Scientific Interest (SSSI) covers an area of 22,770 ha, the site is of interest for its breeding raptors (species as above), blanket bog vegetation, mountain lakes supporting floating water-plantain, examples of watershed mires supporting rare plant species: such as the headwaters of the rivers Elan and Claerwen, the pool & hummock mire at Cors Lwyd and mire complex at Cors Goch. The development is partly located within the SSSI.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

3.1.5. Caban Lakeside Woodlands SSSI The Caban Lakeside Woodlands SSSI covers an area of 11.5 ha and supports a range of mosses and liverworts associated with humid situations with decaying wet wood. The SSSI supports a range of lichens typical of acid barks, naturally basic bark and standing dead wood and has suitable conditions for rare lichen species Catillaria globosa and Ptychographa xylographa. The proposed cable route would run through the most westerly edge of the SSSI.

3.1.6. Caeau Penglaneinon SSSI Caeau Penglaneinon SSSI covers an area of 5.5ha, featuring species rich grasslands. Nominated as county ‘Coronation Meadow’ due to being an outstanding example of species-rich grassland. The proposed cable route is adjacent to the eastern edge of the SSSI.

There are no sites designated for bat, dormouse, or great crested newt interest within 2 km of the site boundary.

Protected and Priority Species Within 2 km of the development 122 protected and/or priority species were provided by the BIS data search. A full list of the 122 species is included in Appendix A with distribution of species in taxon groups provided in Table 1.

Table 1: WWBIC and NBN Gateway grouped protected and/or priority species results Taxon Group No. of Species Key Species with Relation to the Development Insect 57 Includes moths, beetles, butterfly and spiders Lichen, liverworts, moss 38 Stag’s-horn clubmoss, bog pawwort, varnished hook- and clubmoss moss Plant 9 Wood bitter-vetch, fragrant orchid, eyebright, cornflower, chamomile, globeflower, small-flower sticky eyebright Fish 2 Brown trout, Atlantic salmon Bird 55 Red kite, peregrine, skylark, curlew, hen harrier, merlin, song thrush, fieldfare, pied flycatcher, cuckoo, spotted flycatcher, tree pipit, wood warbler, yellowhammer, bullfinch Amphibian 4 Smooth newt, palmate newt, common frog, common toad Reptile 3 Slow worm, common lizard, adder Mammal 24 Otter, badger, water vole, various bat species

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Extended Phase 1 Habitat Habitats recorded on site included:

• Semi-natural broadleaved woodland • Wet modified bog • Plantation coniferous woodland • Flush • Acid grassland • Running Water • Semi-improved acid grassland • Bracken • Marshy grassland • Species poor-intact hedge • Improved grassland • Rock exposure • Dry heath • Buildings/ urban features

A copy of the Phase 1 Habitat Map for the site is provided in Figure Series 2 – Phase 1 Habitat Map. Photographs are provided in Appendix C – Photographic Plates.

3.3.1. Semi-natural broadleaved woodland A small area of semi-natural broadleaved woodland associated with the steep riparian corridor was located within the 25m north of the pipeline (SN 89139 61884). The canopy is open and consists primarily of downy birch Betula pubescens with occasional sessile oak Quercus petraea, goat willow Salix caprea, rowan Sorbus aucuparia and ash Fraxinus excelsior. The ground layer is grazed by sheep and is consistent with the surrounding semi-improved acid grassland (see section 4.6). Bluebells Hyacinthoides non-scripta and bracken Pteridium aquilinum were occasional within the ground flora. (Photograph 4)

The cable route runs along a public footpath with stands of semi-natural broadleaved woodland either side of the track. The stands of woodland are situated on a steep slope leading down to the road. The composition of species within the canopy layer is constant and dominated by sessile oak with occasional ash and downy birch. The shrub layer contains occasional rowan. The ground flora is dominated by bilberry Vaccinium myrtillus abundant with common bent Agrostis cappilaris and frequented with moss species such as lawn moss Rhytidiadelphus squarrosus, wood hair moss Polytrichum formosum and red stem moss. Other grass species found within the woodland was sweet vernal grass Anthoxanthum odoratum. (Photographs 13 and 15)

3.3.2. Plantation coniferous woodland A stand of coniferous woodland is located to the south of the proposed pipeline route SN 89195 61792. The understory is devoid of plant growth and the canopy is dominated by a spruce species.

The cable route runs along a path that is adjacent to a large plantation of coniferous woodland. As before there is no understory and the canopy is a mixture of Norway spruce Picea abies, sitka spruce Picea sitchensis, Douglas fir Pseudotsuga menziesii and Scot's pine Pinus sylvestris with some European larch Larix decidua.

3.3.3. Marshy grassland Areas of marshy grassland totaling 2.67 ha are situated to the north of the site near to the pipeline route (Photograph 9). Large dense tussocks of purple moor grass Molinia caerula dominate the areas. Other grass species present are sweet vernal grass Anthoxanthum odoratum, tufted hairgrass Deschampsia cespitosa occasionally and Yorkshire fog Holcus lanatus rarely. Rush species present within the grassland are soft rush Juncus effesus and articulated rush Juncus articulatus. Herbaceous plants recorded within the marshy grassland were tormentil Potentilla erecta, greater bird’s-foot-trefoil 7

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Lotus pedunculatus frequently, marsh thistle Cirsium palustre, marsh violet Viola palustris and marsh bedstraw gallium palustre were all recorded occasionally within the area. Common sorrel Rumex acetosa, marsh pennywort Hydrocotyle vulgaris, sneezewort Achillea ptarmica, and marsh willowherb Epilobium palustre were found rarely within the marshy grassland. The area is grazed by sheep.

3.3.4. Acid grassland The majority of the pipeline lies within areas of acid grassland (Photograph 5). The distribution of species varies throughout the site but the composition of species remains constant. More dominant grass species include sheep fescue Festuca ovina, sweet vernal grass and common bent. Other grasses found within the sward were red fescue Festuca rubra and Yorkshire fog. The sward is predominantly short as it is grazed by sheep but there are tussocks of mat grass Nardus stricta and tufted-hair grass in areas. Sedge species found with the grassland were common sedge Carex nigra, carnation sedge Carex panicea, green ribbed sedge Carex binervis and star sedge Carex echinata. In wetter areas associated with the riparian corridor rush species become more dominant these include soft rush and sharp flowered rush Juncus acutiflorus. Mosses present were Rhytidiadelphus squarrosus, Pleurozium schreberi, Dicranum scoparium and Polytrichum commune. Tormentil and heath bedstraw were constant throughout the grassland. Lousewort Pedicularis and heath milkwort Polygala serpyllifolia were present in the sward along with meadow buttercup Ranunculus acris, common sorrel Rumex acetosa, sheep sorrel Rumex acetosella and field wood rush Luzula campestris.

3.3.5. Semi-improved acid grassland Areas of semi-improved grassland are located within the development area. These areas are grazed and in places and enclosed by fences. The diversity of species is less than that of the unenclosed acid grassland and is frequented by species more associated with improved grasslands such as perennial ryegrass Lolium perrene and white clover Trifolium repens. However, there is still a diversity of herbaceous plants in parts of the sward and can therefore be classed as good semi-improved acid grassland.

An area of clear-fell coniferous woodland was located adjacent to the cable route. The timing of this was at least five years ago giving the habitat time to rejuvenate and is best described as acid grassland. The sward height is at least 50cm with the dominant species being red fescue, other grass species are sweet vernal grass and common bent grass. Tormentil is occasional with fox glove Digitalis purpurea.

3.3.6. Improved grassland An area of improved grassland is located where the proposed power house and length of pressure pipeline is to be positioned (Photograph 1). The grass is heavily grazed by sheep and cattle and has an abundance of perennial ryegrass and frequented by white clover. Other species found within the grassland are Yorkshire fog, ribwort plantain Plantago lanceolata, creeping thistle Cirsium arvense and common mouse-ear Cerastium fontanum (Photograph 1). Areas adjacent to the river are frequented with soft rush.

3.3.7. Dry heath The proposed cable route runs along the public footpath within areas of dry heath. (Photograph 12). Common heather Calluna vulgaris is the dominant shrub with bilberry being a constant and very conspicuous but the abundance varied across the site. Other common species within this community included tormentil, bell heather Erica cinerea, deergrass Muhlenbergia rigens, heath bedstraw and purple moor-grass Molinia caerulea. Other forbs present included ribwort plantain and heath milkwort. There were occasional patches of male-fern Dryopteris filix-mas. The ground layer was abundant with 8

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal moss species such as red-stem Pleurozium schreberi, Hylocomium splendens and common haircap moss Polytrium commune. There were occasional small rowan seedlings present up to about 50 cm tall. Tormentil occurs frequently along with heath bedstraw. Grass species that were recorded are sheep’s fescue, red fescue, common bentgrass and sweet vernal grass, however these are less dominant than the Erica species. Rarely occurring species were barren strawberry Ranunculus strerilis, common sorrel and foxglove. The lichen Cladonia sp. was occasional throughout the habitat. At the very start of this habitat from the main road, bracken is abundant.

3.3.8. Wet modified bog An area of wet modified bog was surveyed at where the intake compound is to be located. The vegetation resembles that of a drying degraded blanket bog. In the wetter areas, there are Sphagnum sp. that appear to be drying out. Among the bryophyte species recorded are Pleurozium schreberi, Rhytidiodelaphus sp. and Polytrichum commune in places these species dominate giving an indication of the degradation of the bog as it has become too dry. Other species present are sedges such as the cotton grass Eriophorum angustifolium and Eriphorium vaginatum. Grass species recorded were tufted hairgrass, sweet vernal grass, common bent. Herbaceous plants consisted of creeping cinquefoil Potentilla reptans.

3.3.9. Flush A flush was located within the acid grassland. This is sphagnum sp. rich with an abundance of small sedges. Sedge species include the two species of cotton grass, carnation sedge, star sedge and common sedge. In the wetter areas species such as common butterwort Pinguicula vulgaris, bog asphodel Narthecium ossifragum and round-leaved sundew Drosera rotundifolia were recorded. Other species observed were marsh violet, greater bird's foot trefoil and heath-spotted orchid Dactylorhiza maculata.

3.3.10. Intact species-poor hedge There are two traditionally laid hedgerows that separate the improved grassland fields where the power house is to be located. They are species poor with willow, hazel Corylus avellana, rowan and beech Fagus sylvatica. The ground flora is consistent with that of the surrounding improved grassland.

3.3.11. Running water The Afon Claerwen runs from west to east to the north of the site. An area of the river is located within the site boundary to the north of the site. The river was fast flowing with many large boulders.

Small streams are present throughout the development ZoI. Target notes 3 and 4 show the location of small streams that are associated with the species poor hedgerows. The stream at the time was slow flowing and is flanked by shallow banks that are have the frequent presence of soft rush and bramble Rubus fruticosus.

3.3.12. Buildings An old stone building was located along the pipeline construction zone (Photograph 6). The building was in a very poor state of repair with goat willow trees growing within it.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Protected and Priority Species Protected and priority species recorded on site during the survey included:

• Wheatear (Oenanthe oenanthe) • Small copper (Lycaena phlaeas) • Long tailed tit (Aegithalos caudatus) • Greylag geese (Anser anser) • Meadow pipit (Anthus pratensis) • Green dock beetle (Gastrophysa • Red kite (Milvus milvus) viridula) • Raven (Corvus corax) • Otter (Lutra lutra)- scat • Dipper (Cinclus cinclus)

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

4. Development Aspects with Potential for Significant Ecological Effects

Construction Aspects During the construction phase, there will be direct loss of a linear strip approximately 2.5 km of land spanning approximately 20m wide plus associated construction compounds. The total land take required for construction is 6.22 ha. Construction details are described in Chapter 4.

In summary, the main construction elements are:

• Creation of a 1.7 km pipeline up to 2.8 m excavation • Creation of a concrete tailrace • Installation of Coanda screens and concrete conveyance channel into intake chamber. Intake chamber (including any pumps required) will be finished with stone facing. • Powerhouse (0.008ha / 10m x 8m) block built with stone face • Intake construction compound – approximately 0.06 ha temporary land take and powerhouse construction compound – approximately 0.11 ha temporary land take. Both will have turf removed and filled with gravel. Soils to be stockpiled and reinstated at end of construction phase. • Pipeline will only be built in 200m sections with temporary French drains and silt traps installed. Soils will be stockpiled along the pipeline before reinstating and landscaping once each section is complete. • In river works for watercourse crossings will include: • the fluming and surfacing of the streams to enable vehicle access up to the intake and upper penstock section • The removal of fluming/ access arrangement followed by temporary diversion of the tributary to enable burial of the penstock below the tributary bed • The reinstatement of the natural tributary bed and restoration of normal flow. • Each watercourse crossing will take up to three weeks and will take place between June and September. • Construction to last between 9-12 months. Some works must be completed during spring/ summer due to abstraction license conditions

Operational Aspects During operation, there will be no ongoing physical or direct works to the built hydro scheme. Activities will be limited to monitoring and maintenance. The coanda screens that will be installed are self-cleaning with the exception of large build-up such as branches, leaves and general river material. This will be cleaned out by hand, as will the intake channel, intake/syphon chamber and tailrace.

The powerhouse will require ongoing access and maintenance. This will be via a van or standard road going four-wheel drive vehicle. Maintenance to the powerhouse is largely restricted to the internal workings such as the turbine and control panels etc. The building fabric will be maintained as required with it being possible to use the access track to temporarily store material (i.e spare slates, scaffolding for re-roofing after approximately 60-100 years).

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

5. Habitat Regulations Assessment – Screening Information

Species and habitats of conservation status is considered in relation to their inclusion on the EC Habitats Directive (94/43/EEC) and Conservation of Habitats and Species Regulations 2010 (as amended). For wild birds, species of conservation status is considered in relation to their inclusion on the EC Birds Directive (79/409/EEC). In practice, these features are identified as designated sites including SACs (habitats and species exc. Wild birds) and SPAs (wild birds). The development is in close proxcmity and at times within three SAC and SPA. As described in Section 3.1, these are the Elenydd SAC, the Elan Valley Woods SAC and the Elenydd-Mallaen SPA.

Article 6(3) and (4) of the EC Habitats Directive (94/43/EEC) requires an Appropriate Assessment for “Any plan or project not directly connected to the management of the site but likely to have a significant effect thereon, either individually or in combination with other plans or projects”. It is therefore considered that a methodological approach using European Commission Environment DG’s ‘Assessment of plans and projects significantly affecting Natura 2000 sites’ (2001). This approach will use the following four stage process to assess the need and scope of Appropriate Assessment:

• Stage One Screening - identification of likely impacts alone or in combination; • Stage Two Appropriate Assessment - Consideration of the impact upon the identified features of the Natura 2000 site alone and in combination with other plans and projects with respect to that sites conservation objectives; • Stage Three Assessment of Alternatives - Where adverse impacts are identified, this stage assesses the alternative mechanisms of delivering the desired result without having adverse impacts; • Stage Four - An assessment of compensatory measures required where no alternatives exist and the scheme is adjudged to need to proceed on the grounds of Imperative Reasons of Overriding Public Interest (IROPI).

At any point in the process depending upon the results of that part the process may be able to cease. A copy of the flow chart for Article 6(3) and (4) procedure in relation to the aforementioned stages of the guidance is provide in Figure 1.

To facilitate discussion with the Local Planning Authority, Powys County Council, and the Statutory Nature Conservation Organisation, Natural Resources Wales, a matrix of impacts that includes direct and indirect effects; short and long-term effects; construction, operational and decommissioning effects; and, in-combination and cumulative effects has been prepared. The methods used to predict these effects will be based on the direct measurements of habitat loss using GIS software and will display the area lost and proposals for in-situ mitigation. Compensation measures are not being included in the assessment.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Figure 1: Flow chart for consideration of effects on a Natura 2000 site (European Commission, 2001)

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Elenydd-Mallaen SPA

5.1.1. Elenydd-Mallaen SPA and the Development Zone Figure 2 demonstrates that the development falls almost entirely within the Elenydd-Mallaen SPA. The SPA itself is designated for its breeding season populations of peregrine (1.3% of UK population), red kite (9.4% of UK population) and merlin (0.5% of UK population). In terms of breeding requirements for these species, none of the habitats present offer nesting potential for red kite or peregrine falcon.

Figure 2: Elenydd-Mallaen SPA and the Development Zone of Influence (ZoI) (yellow is the SPA extent; blue diagonal lines is the SSSI extent; red boundary is the development ZoI; and orange is the cable route and construction access route to the site). The Extended Phase 1 Habitat Survey confirmed that there are no specific optimal heath habitats in the development zone itself and that the majority is acid and marshy grassland with a few small areas of sub-optimal habitat that may be use including wet modified bog and flush. However, it should be noted that the byway that runs through the length of the development zone is heavily used by off-road enthusiasts and is therefore well disturbed. The Extended Phase 1 Survey and breeding bird survey conducted during May and June 2017 also confirmed absence of nesting merlin throughout the development zone.

The development site however does remain to provide hunting and scavenging ground for all three species and this will be at least temporarily lost during construction works. The long-term effects of the built development are likely to be negligible because the only above ground elements will be the intake weir and chamber, realigned access track locations, the powerhouse and tailrace. Given the

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal small footprint that these will equate to (i.e. less than 1 ha) it is unlikely that a significant change in the availability of prey species (such as upland passerines) and carcasses will occur.

5.1.2. Elenydd-Mallaen SPA and the Cable Route Figure 3 demonstrates that the cable route only partly falls within the Elenydd-Mallaen SPA. The cable route follows a series of forest tracks and open pathways. To the southwest portion of the cable route approximately 800m passes through the SPA. The immediate surrounding habitats (i.e. within 50m either side of the route) contains semi-natural deciduous woodland, dens/continuous bracken, scattered bracken, mixed semi-natural woodland and dry dwarf shrub heath. The breeding bird survey results (Environment Systems, 2017) shows that no nests were found in this area and there was a general lack of results for the qualifying species. The habitats however remain of interest to these species and do offer a range of services to individual birds such as day and night roosting, hunting and scavenging.

Figure 3: Elenydd-Mallaen SPA and the central region of cable route ZoI (yellow is the SPA extent; blue diagonal lines is the SSSI extent; orange is the cable route and construction access to the development site; and red boundary is the development ZoI). Given the type of works to be undertaken to construct the cable route (i.e. trench, cable laying and re- surfacing) it is likely that the only impacts are disturbance and displacement. The built asset will be buried so there will be no long-term habitat loss. Although construction of the development itself will need to be completed during spring/summer months to tie-in with Flood Risk Activity Permitting and other water environment requirements such abstraction licensing, the cable route can be timed to avoid the main breeding season for important bird species.

Figure 4 demonstrates that the cable route will also pass along the boundary of the SPA at the northeast end of the cable route. At this location, the cable will be buried into the existing tarmac road and is therefore not going to result in temporary or permanent habitat loss. Works may be a

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal disturbance which could temporarily displace birds within 300-500m of the works due to loud noise. However, this is no more uncommon then a normal re-surfacing of the road itself and is unlikely to be a long-term significant effect. Similar to the southern section of the cable route, it is possible to avoid the breeding bird season to install the cable in this location late July onwards (subject to Ecological Clerk of Work monitoring and checks of the nearby disused quarry).

Figure 4: Elenydd-Mallaen SPA and the northeast section of the cable route ZOI (yellow is the SPA extent; blue diagonal lines is the SSSI extent; orange is the cable route and construction access to the development site; and red boundary is the development ZoI).

5.1.3. Elenydd-Mallaen SPA Screening Summary The bird species of conservation concern for the SPA have not been found to be currently nesting within 500m of the development zone or cable route. Disturbance and displacement will occur during the construction works at any point in the year as there will be a temporary loss of hunting, scavenging and roosting habitat. It is however considered that there is sufficient alternative habitat to supply these required features for the short construction period as each 200m section is completed and works advanced along the linear route. The effects on the SPA are therefore likely to be very limited and will not affect the long-term population status’ of any of the three species of importance.

Elan Valley Woods SAC Although the Elan Valley Woods SAC is located within the 50m zone of influence of the cable route, only two patches are directly affected digging and trenching work to bury the cable. Figure 5 shows the locations where the cable route intersects the SAC. At these locations both areas of woodland were found to be mixed semi-natural woodland during the Extended Phase 1 Habitat Survey. The figure also demonstrates that the cable route has been designed to buried in the existing forest track to reduce impact on any of the surrounding habitats. The only likely effect therefore is construction dust settling on vegetation important to the SAC feature (old sessile oak woods and Tilio-Acerion forests of slopes, screes and ravines) which includes an assemblage of bryophyte and lichen species. 16

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

To prevent significant effects relating to dust accumulation and change in pH levels etc., of base habitats for bryophytes and lichens a Dust Management Plan (DMP) will be implemented. Information to be taken forwards into a draft DMP is included in Appendix D – Dust Management Plan Information. This will be refined through discussion and consultation with NRW and the construction contractor to ensure fit-for-purpose measures will be installed for each section of trenching that has potential to affect the receiving SAC features.

Figure 5: Elan Valley Woods SAC intersections with the cable route (green shows the SAC extent and orange is the cable route ZoI following the existing forest track).

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Elenydd SAC The Elenydd SAC is located over 500m from the cable route at its nearest point and over 900m from the development at its nearest point. A copy of the designations plan showing the various designated sites is provided in Figure Series 1 – Designated Sites Plan. Caliminarian grassland of the Violetalia calaminarie which is reliant on heavy metals from former mining works is one of the qualifying features of the SAC. Given the absence of these habitat types and environmental factors that need to come together to form this type of habitat, it is certain that this habitat will be unaffected by the development of cable route works.

Blanket bogs and mire is another primary reason for designation of this SAC. This habitat has potential to also be present outside of the SAC itself and may be designated under SSSI status elsewhere. Within the likely zone of influence (i.e. within 40-50m of the pipeline and cable routes) there is one small area of wet modified bog and one area of flush. These are surrounded by marshy and acid grassland which is generally in poor condition due to extensive sheep grazing.

European dry heaths are a feature of the SAC but not a primary qualifying feature. Within the development zone of influence there are three area of dry dwarf shrub heath. All three areas are located within 50m of the cable route. Only one of these areas will be directly affected by digging works with the other two only affected by aspects such as construction dust. The Extended Phase 1 Habitat Survey confirmed that these habitats are typical of the dry heath vegetation communities found in the local area. By using commonly used and appropriate mitigation measures such as turf lifting, storage and replacement with enhancement via re-seeding from local provenance it will be possible to return the trenching part of the habitat can be satisfactorily restored once construction is complete. The areas adjacent to the cable route can be protected by dust suppression measures such as damping down.

Other features such as oligotrophic and mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or of the Isoeto-Nanojunctea and floating water pennywort are unlikely to be affected by the works both temporarily and permanently due to their absence and distance from the working zone of influence.

In summary, the Elenydd SAC is unlikely to be significantly affected by the development at both construction and operational stages. A small area of supporting dry heath habitat will be directly affected but can be easily mitigated. Given that this habitat is at a sufficient distance from the SAC itself, there will be no significant impact to the habitat itself (i.e. there will be no long-term habitat fragmentation or loss of habitat extent).

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

6. Discussion

Designated Sites Designated sites include SSSI, NNR and LNR. SACs and SPAs are included in Section 5.

6.1.1. Elenydd SSSI The intake weir and pipeline is partly located within the Elenydd SSSI. Within the SSSI area of the development ZoI 11 habitats are present. The estimated temporary loss of the habitats is shown in Table 2. The planned works will include the turf stripping and retention to be replaced.

Table 2: Development area by habitat within Elenydd SSSI Habitat Area of development within SSSI habitats Intake weir, pipeline, powerhouse and tailrace Coniferous plantation 0.04 ha Acid grassland 3.37 ha Semi-improved acid grassland 3.45 ha Improved grassland 0.03 ha Marshy grassland 1.08 ha Scattered bracken 0.06 ha Wet modified bog 0.08 ha Flush 0.05 ha Rock exposure 0.08 ha Track 0.6 ha Cable route Acid grassland <0.01 ha Continuous bracken 0.07 ha Dry dwarf heath 0.52 ha Mixed semi-natural broadleaved woodland 0.16 ha Coniferous plantation 0.03 ha Scattered bracken 0.02 ha Semi-improved acid grassland <0.01 ha Semi-natural broadleaved woodland 0.05 ha Track 0.28 ha Features highlighted in orange are those identified as features of the SSSI.

Wet modified bog As originally proposed, the location of the construction compound at the intake weir is located partly on wet modified bog which can be very difficult to restore once disturbed. Assessing the available scattered bracken and acid grassland adjacent suggests that the construction compound could potentially be optimised to avoid the bog itself. This would effectively reduce the available working width at the intake weir but would protect the majority of the wet modified bog and so the feasibility of this is would be taken forward into more detailed review and assessment in more detailed design stages. There will also be opportunity within the construction period to implement restoration techniques to improve the condition of the bog. Subject to stakeholder consultation and agreement this may include identifying and blocking of small watercourses or installing impermeable plastic 19

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal corrugated along flow pathways to encourage re-wetting of the wet modified bog area. The resulting paludification effect would be a low-energy area of ponded water and higher water levels in the section of bog immediately upslope of the dam, encouraging development of hummock-forming species of Sphagnum bog mosses. The overall effects once a suitable method has been implemented it is likely that although the SSSI feature is of high conservation status the ultimate effect would result in a minor positive impact.

Grassland The loss of acid and marshy grassland, the majority of which will be temporary with the laying of the pipeline, is locally extensive and of typical diversity for the region. This suggests that the limited loss will not affect the long-term integrity of the SSSI. Nevertheless, to ensure that the habitat is restored to its current diversity a methodology for extracting existing areas of acid and marshy grassland will be implemented. The overall effects once a suitable method has been implemented, such as that recommended in Appendix F – Grassland/Heath Extraction and Restoration Method, it is likely that although the SSSI feature is of high conservation status the ultimate effect would result in a negligible to minor impact.

Flush The UK BAP priority habitat upland flush is defined as ‘peat or mineral-based terrestrial wetlands in upland situations, which receives water and nutrients form surface and/or ground water sources as well as rainfall'. It is a varied habitat category but is typically dominated by sedges and their allies, rushes, grasses and occasionally wetland herbs and/or a carpet of bryophytes’ (Maddock, 2008). The acid flush habitat within the site is equivalent or approaching this definition. Upland flush UK BAP habitat is widespread but local throughout the Wales (Maddock, 2008). The extent of this habitat has not been recorded as it has not been comprehensively surveyed in many areas (Maddock, 2008). There was 0.06 ha of acid flush within the site. The quantity and condition of this habitat is considered of local importance. The flush will be affected by proposed layout but impacts could be minimised by micro-siting and implementing methods to retain soils and strip turves in the method provided in Appendix F. The overall effects once a suitable method has been implemented it is likely that although the SSSI feature is of high conservation status the ultimate effect would result in a minor impact.

Dry dwarf heath UK BAP dry dwarf shrub heath (within the upland heath BAP habitat) in favourable condition is defined as being ‘dominated by dwarf shrubs such as ling heather, bilberry, crowberry and bell heather’ (Maddock, 2008). Annex 1 European dry heath includes dwarf shrub dominated vegetation with ling heather, bilberry and bell heather (JNCC, 2013). The dry dwarf shrub heath is similar to these definitions. There was 0.52 ha of dry dwarf shrub heath within the cable route and the heath extends extensively to the north and west from this point. The temporary loss of the heath along this stretch of the cable route is unlikely to be considered of significance as it will be possible to restore the heath area once the cable has been installed. The route follows the existing footpath through the heath (Photograph 12) but will need some equipment to dig enough of a trench to install the cable. Therefore, temporary loss is likely to be restricted to within 5 m of the path itself. The overall effects once a suitable method has been implemented, such as that recommended in Appendix F, it is likely that although the SSSI feature is of high conservation status the ultimate effect would result in a negligible to minor impact.

Semi-natural broadleaved woodland The planned route of the cable is to follow existing roads, tracks and footpaths. At two locations adjacent to Craig y Mynach (NGR 290424, 261714) the cable route will be in close proximity to the woodlands. It is planned to use a micro-siting approach at these locations to prevent any direct 20

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal effects on the woodlands. This will be achieved by calculating the Root Protection Areas (RPAs) in accordance with BS5837:2012 Trees in relation to design, demolition and construction and installing suitable fencing to act as no work and no dig areas. The protection zone will be maintained for the duration of the works and no access permitted including for storage of materials, ground disturbance, burning and/or contamination within the fenced area. Given that effects on the woodland will be avoided the impact would be negligible.

6.1.2. Caban Lakeside Woodlands SSSI The cable route will pass through the Caban Lakeside Woodlands SSSI (shown in Figure 6). At both locations, there is an existing forestry track which is generally well used (Photograph 16). The cable route is intended to follow the track throughout its entire length, at no point will the works deviate from the track itself. It is therefore considered that the effects will be limited to dust arising from the digging of the trench and accidental spillages. Both aspects can be easily mitigated by using damping down methods and ensuring that any refueling and mixing required is completed outside of the SSSI and transported into the work location along the track. Dust arising from vehicles travelling along the track is only slightly increased beyond normal levels of use. This is likely to result in a negligible to minor negative impact (i.e. not significant).

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Figure 6: Cable route and Caban Lakeside Woodlands SSSI & Caeau Penglaneinon SSSI (green shows the Caban Lakeside Woodlands SSSI; blue shows the Caeau Penglaneinon SSSI and orange is the cable route ZoI following the existing forest track).

6.1.3. Caeau Penglaneinon SSSI The cable route will pass along the side of Caeau Penglaneinon SSSI (shown in Figure 6). At no point will the cable route enter the SSSI. Dust arising digging and from vehicles travelling along the track is only slightly increased beyond normal levels of use and is likely to result in a negligible to minor negative impact (i.e. not significant).

Invertebrates Invertebrate surveys were previously completed during 2011 along the Afon Claerwen. Although the results are now likely to be out of date, they do provide a baseline of information that can be used to help inform the need for assessment. A copy of the Technical Note prepared at the time of survey is provided in Appendix E – Twyi and Claerwen Invertebrate Survey: Technical Note.

Biological Monitoring Working Party (BMWP) and Average Score per Taxon (ASPT) were calculated for each of the invertebrate samples. The total scores which is a combination of values from each taxon are banded into poor, moderate, good, very good and, excellent water quality. Lotic- invertebrate Index for Flow Evaluation (LIFE) scores were also calculated to represent benthic invertebrate data to flow regime and flow ranges. Finally, species rarity for invertebrates was recorded using the Red Data Book and Nationally Scarce statuses provide by JNCC.

In summary of the aforementioned technical note the samples taken from the Claerwen demonstrated moderate biological water quality. Scoring taxa (BMWP) was an increasing trend from sample location C1 above the proposed intake weir location to the downstream sample location C6a near the proposed tailrace. ASPT scores demonstrated a different pattern but still with the highest score at the downstream sample locations. LIFE scores were similar across all six sample locations. No legally protected, UK or Local Biodiversity Action Plan or Red Data Book invertebrate species were recorded. No mollusc or crustacea species were recorded.

The results indicate that there is limited invertebrate interest in the Afon Claerwen and that this is likely to be linked to acidification, nitrogen pollution, habitat degradation, afforestation and base-poor geology within the catchment. The invertebrate interest is therefore considered as a negligible to low ecological receptor and is not recommended to be taken forward into full EcIA.

Reptiles There are records of two reptile species within the area and it is considered that reptile species such as slowworm Anguis fragilis, grass snake Natrix natrix and common lizard Zootoca vivipara are widespread and under recorded.

The heathland adjacent to the cable route is of value for reptiles, offering foraging opportunities along with the woodland that have the potential to support reptiles. No hibernacula were found on site during the Extended Phase 1 Habitat Survey.

Common reptile species may occasionally be present within the heathland however this habitat is not intended to be affected by the construction and operation phases and can be easily mitigated. A watching brief will be employed to supervise the grass removal and soil strip ahead of pipeline installation and laying the power cable. Where required additional measures such as purpose-built reptile fencing will be erected, however this is not considered necessary at this time. 22

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Birds The site supports a range of birds typical of habitats within the area, including potentially some of conservation interest. Elenydd-Mallaen SPA located directly adjacent to the site, supports red kite, peregrine and merlin which may occasionally forage across agricultural land in the area. The effects on these species is discussed in Section 5.1.

Passerine species such as pied flycatcher, yellowhammer, bullfinch and spotted flycatcher etc. which are more associate with woodland and hedged farmland habitats are all know to be present in the area. A breeding bird survey is currently in progress and will be reported separately to give a more in- depth overview of the breeding bird assemblage that may be affected by the development and cable route. To date the surveys, show that standard mitigation measures can be employed to avoid disturbance and displacement during the breeding season.

In order to avoid impacts on nesting birds and to ensure compliance with the provisions of the Wildlife and Countryside Act 1981 (as amended), it is recommended that any initial ground works and associated vegetation removal take place outside (i.e. September-February inclusive) of the bird breeding season. If vegetation works are necessary during the breeding season, breeding birds and their nests will be protected by a watching brief. Potential nesting habitat would be hand-searched by a suitably experienced ecologist prior to works commencing. Only once the appointed ecologist is satisfied that site clearance works will not result in harm to breeding birds may works proceed.

Existing traditional hedge laying techniques have already been employed along a number of the field boundaries to the eastern part of the pipeline. These will provide enhancement to farmland birds and further habitat enhancement can be advised, although scope for this is limited given the landscape type and habitats already present on site.

Otter & Water Vole A search of the river and watercourses within the 100m of the pipeline was conducted during the Extended Phase 1 Habitat Survey. The weather conditions preceding the survey were dry for at least 48 hours meaning any evidence was likely to be retained and found during the survey. There are also records of otter and water vole within the vicinity from the local record centre search.

An otter scat was found at the western end of pipeline route on the existing byway track. A number of features on the Afon Claerwen were found to be suitable to support otter. These include a slide over protruding base rock on the north bank approximately 55m from the development ZoI (NGR: 289393, 261885). A second suitable holt location was found approximately 113m from the development ZoI (NGR: 289016, 262147).

No features or evidence of otter presence was found along the small watercourses which cross the development zone. These small watercourses varied from having some flow to being heavily trampled wet areas which had been closely cropped by livestock (sheep) or damp linear depressions with occasional water pools dominated by soft rush.

No evidence of water vole was found throughout the development ZoI.

As otters are a highly mobile species, there is always potential for otters to move around the development site and surrounding area as part of a wider territory. At present, there are no features which appear suitable to provide a couch or holt within 100m of in river works. There is a small risk for individual otters to attempt to move through or investigate the construction zone and become

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal entrapped within excavations such as pipeline trenches, borrow pits and building foundations during the construction and decommissioning phases. There is also potential for otters to enter uncapped pipes during night-time hours to take refuge (i.e. lie-up for a day), and become trapped inside the pipes (potentially leading to harm).

Disturbance to otters is only likely to occur during construction and decommissioning phases. During operation of the development the only disturbance will come from cleaning the intake weir and tailrace of debris (i.e. leaves, sticks, logs and stones). Maintenance works to the powerhouse and intake chamber etc., will be limited to 4x4 vehicles with small hand-held tools and equipment. During construction disturbance by machinery and human movements as well as noise and blast/vibration impacts are likely to lead to the temporary abandonment of any use of the Afon Claerwen and surrounding areas by otters in that period. It is evident that otter use the river and that the works may cause temporary displacement.

Without following best practice during the construction period there is potential for sediment-laden run-off and pollutants (i.e. fuel, chemical and concrete spills etc.,) to enter the Afon Claerwen, which could affect to the aquatic environment on which otters rely. Should this type of incident occur, it is almost certain that the availability of prey, as well as the ability of otters to commute and rest within their habitual range will be affected. This could lead to loss of failed attempts to rear young or displacement from a territory. Therefore, best practice such as Planning Policy Guidance Notes 5 & 6 will be applied and followed through the construction management plan with an Ecological Clerk of Works appointed to check and monitor measures including silt traps and fuel bunds and working zones are all implemented and adhered to in order to prevent these potential negative effects.

Badger The desk study results confirmed that badgers are known to be present in the area. The Extended Phase 1 Habitat Survey confirmed that a mixture of optimal and sub-optimal habitats that provide for sett building and foraging opportunities are present. The construction zone of the pipeline itself is largely of sub-optimal sett-building habitat due to the exposed nature of the acid and marshy grassland present. However, a number of habitat features such as a small area of coniferous woodland, the wooded area below the disused mine and the wooded river corridor all offer some opportunity.

During the Extended Phase 1 Habitat Survey a search for signs of badgers (e.g. existing and disused setts, pad marks, latrines, hairs or obvious setts) was conducted. The search was completed throughout the construction zone and up to 50m from the construction ZoI (including the cable route). No evidence was found during the survey, particularly there was absence of any signs of existing or disused setts, fox earths and rabbit warrens. It is therefore considered, that at present badgers are likely absent from the development in terms of resting, mating and rearing cubs. However, it remains likely that badgers do pass through and use the construction area for commuting and foraging as they are highly mobile species.

In line with standard good construction practice ground excavations during the construction phase will be covered overnight or fitted with a means of escape for badgers and other species (i.e. otter, water vole, amphibians and reptiles etc., as described above) that could become trapped. All construction materials will be stored in secured compounds or raised off the ground.

It will also be necessary to ensure that prior to construction badgers are still absent from the development ZoI by undertaking pre-construction surveys within at least 50m of construction works. If

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal a sett(s) are identified within 30m and works are considered to be of a scale and duration that could cause disturbance, a scheme of mitigation will be agreed and implemented.

Bats The desk study results confirmed that several bat species are known to be present in the area including: brown long-eared bat; Daubenton’s bat; Natterer’s bat; soprano pipistrelle; common pipistrelle; whiskered bat; and Brandt’s bat.

The Extended Phase 1 Habitat Survey confirmed the presence of a number of features that provide suitable habitat for roosting and foraging including numerous mature trees, the Afon Claerwen and other waterbodies, the network of hedgerows and areas of woodland.

There are several mature trees within and in close proximity of the construction zone. At present, it is understood that none of the trees will be removed and can be retained post-construction. It is therefore unlikely that there will be negative effects on bats arising from the development proposals.

The laying of the pipeline and infrastructure associated with the development is not anticipated to result in the significant loss of foraging habitat or fragmentation of linear features, which may provide important flight routes for bats. The semi-improved grassland that is directly affected offers relatively good quality foraging habitat for bats as there will be a high number of insect prey, however due to the lack of linear features and trees within the pipeline development site, the habitat is considered to be of low interest for bats. The operational site will not be lit at night and hence no lighting effects will occur.

Other Notable Species No other notable species were encountered during the survey and none are considered pertinent to the appraisal. No sightings of brown hare or hedgehog were made. However, brown hare and hedgehog have been recorded within the surrounding area and may occasionally frequent the habitats of the site.

In line with standard good construction practice ground excavations during the construction phase should be covered overnight or fitted with a means of escape for mammals or other species that could become trapped. All construction materials should be stored in secured compounds or raised off the ground.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

7. Conclusion

The development site contains features of nature conservation ranging from international importance to site level value. The Extended Phase 1 Habitat Survey and desk study confirms the quality of these habitats and where there is risk to the integrity of these features as well as the opportunities to restore them to achieve biodiversity gain.

Habitats in the construction zone of the development itself (i.e. the intake weir, construction compounds, pipeline, re-aligned track sections, powerhouse and tailrace) are of high conservation value being BAP priority and features of designated sites. The highlight habitat is the wet modified bog where the intake construction compound has been located in the current layout. Although the bog is of low quality in itself, it is of conservation importance and forms part of the SSSI interest. Work is therefore underway to assess alternatives to locating the construction compound in the adjacent scattered bracken and acid grassland. This would be likely to have a lesser impact in the long-term as there will be more confidence in restoring these habitat types. It is likely that there will still remain some land take from the wet modified bog and that this will need mitigating or compensating. Subject to stakeholder engagement and consultation there is an opportunity in doing this to commit to helping restore the wet modified bog by re-wetting and implementing a management regime (i.e. temporary stock exclusion). This approach will require consultation and agreement of measures with Natural Resources Wales and the landowner/tenant. The remaining feature such as the acid grassland and marshy grassland can be mitigated by storing turf and replacing like-for-like. The construction process is proposed to be in 200m lengths of pipeline which will allow for storage of soils and turf. Although there will be a temporary loss of habitat the medium-long term effect will be negligible and therefore not considered a significant impact to the habitats themselves as ecological receptors or the designated sites which they may form a supporting feature.

Field survey has demonstrated the presence of otters (although no otter holts or couches are present in the construction zone) and a range of bird species (although none were found to be nesting in the construction zone itself). Other species (i.e. are reptiles, badger, bats) known to be in the area and have the potential to enter the construction site at any time. Mitigation measures that are well understood can be implemented to ensure that the temporary loss of habitat resulting in disturbance and displacement to protected and priority species can be minimised to a negligible – minor adverse impacts.

The next stage of the project will be to discuss the findings of the Preliminary Ecological Appraisal in further detail with the Local Planning Authority’s ecologist and Natural Resources Wales. Drafted method statements for minimising the effects of dust on lower plants and managing the vegetation strip in grassland and heath are presented in Appendix D and F respectively. These can be adapted and developed further, if necessary. Provided that the mitigation measures identified are prepared into working method statements as part of the construction management plan then the residual impacts of the development will be limited and are unlikely to significantly affect nature conservation as a whole.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

8. References

British Bryological Society (2010). Mosses and Liverworts of Britain and Ireland a Field Guide.

CIEEM (2016) Guidelines for Ecological Impact Assessment in the UK and Ireland: Terrestrial, Freshwater and Coastal, 2nd edition. Chartered institute of Ecology and Environmental Management, Winchester.

Cheffing, C M and Farrell, L (Eds) (2005). The Vascular Plant Red Data List for Great Britain (2005). ISSN 1473-0154 (Online), JNCC/gov/uk/

Collins, J. (ed.) (2016) Bat Surveys for Professional ecologists: Good Practice Guidelines (3rd edn). The Bat Conservation Trust. London. ISBN-13 978-1-872745-96-1

Council of Europe (EC) 1979/104/ EC of 19th September 1979 on the convention on the conservation of European wildlife and natural habitats

Council Directive (EC) 1992/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora

DEFRA (2007) Hedgerow Survey Handbook, 2nd Edition. London.

Environment (Wales) Act 2016, Cardiff, HMSO

European Commission (2002). Assessment of plans and projects significantly affecting Natura 2000 sites European Commission, Luxembourg

Holman et al (2014). IAQM Guidance on the assessment of dust from demolition and construction, Institute of Air Quality Management, London. www.iaqm.co.uk/ text/guidance/construction-dust- 2014.pdf.

JNCC (2010). Handbook for Phase I Habitat Survey – A Technique for Environmental Audit. JNCC, Peterborough.

JNCC (2006). Rodwell, JS. National Vegetation Classification Users Handbook.

Lindsay, R. (2010) Peatbogs and carbon: a critical synthesis to inform policy development in oceanic peat bog conservation and restoration in the context of climate change. University of East London. Available online: https://www.rspb.org.uk/Images/Peatbogs_and_carbon_tcm9-255200.pdf

Maddock, A (ed.). 2008. UK Biodiversity Action Plan; Priority Habitat Descriptions. BRIG

NRW Hydropower Guidance Note: HGN 6 Nature Conservation, Heritage, Amenity and Landscapes

NRW Hydropower Guidance Note: HGN 10 Geomorphology

Planning Policy Wales. Chapter 5 – Conserving and improving natural heritage and the coast. 8th edition.

Protection of Badgers Act 1992 (C.51), London; HMSO

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Rodwell (1992) British Plant Communities Vol 2: Grasslands and Montane Communities. Cambridge University Press.

Rodwell (1991) British Plant Communities Vol 3: Mires and Heaths. Cambridge University Press.

Rodwell (1991) British Plant Communities Vol 1: Woodlands and Scrub. Cambridge University Press.

Rose, Francis (1989) Sedges, Rushes and Ferns of the British Isles and North Western Europe. Penguin.

Rose, F. (2006). The Wild Flower Key (Revised Edition) - How to identify wild plants, trees and shrubs in Britain and Ireland. Warne; Rev Ed edition

Ruddock, M., Whitfield, DP. (2007) A review of disturbance distances in selected bird species. Scottish Natural Heritage.

Strachen, R. (2015) Otter survey of Wales 2009-2010. Natural Resources Wales

Strachen, R. & Moorhouse, T. (2006) Water vole conservation handbook. Wild Cru

The Conservation of Habitats and Species Regulations 2010, No. 490

The Countryside and Rights of Way Act 2000 (C.30), London; HMSO

Wildlife and Countryside Act 1981 (C.69), London, HMSO

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Figures

Figure Series 1 – Designated Sites Plan Designated Sites Plan – Whole Development

Designated Sites Plan – Development

Designated Sites Plan – Cable Route Southwest

Designated Sites Plan – Cable Route Central South

Designated Sites Plan – Cable Route Central North

Designated Sites Plan – Cable Route Northeast

Figure Series 2 – Phase 1 Habitat Map Phase 1 Habitat Map – Pipeline West

Phase 1 Habitat Map – Pipeline East

Phase 1 Habitat Map – Cable Route Southwest

Phase 1 Habitat Map – Cable Route Central South

Phase 1 Habitat Map – Cable Route Central North

Phase 1 Habitat Map – Cable Route Northeast

Afon Claewen Hydro Scheme

¯ Designated Sites Plan - Whole Development

Key: Development Site Boundary Cable Route Site of Special Scientific Interest Special Area of Conservation Special Protection Area

0 1,000 Meters

Crown copyright and database rights 2017. Ordnance Survey 0100031673

Date: 19/06/2017 Scale: 20,000 Afon Claewen Hydro Scheme

¯ Designated Sites Plan - Development Site

Key: Development Site Boundary Cable Route Site of Special Scientific Interest Special Area of Conservation Special Protection Area

0 320 Meters

Crown copyright and database rights 2017. Ordnance Survey 0100031673

Date: 19/06/2017 Scale: 6,500 Afon Claewen Hydro Scheme ¯ Designated Sites Plan - Cable Route Southwest

Key: Development Site Boundary Cable Route Site of Special Scientific Interest Special Area of Conservation Special Protection Area

0 250 Meters

Crown copyright and database rights 2017. Ordnance Survey 0100031673

Date: 19/06/2017 Scale: 5,000 Afon Claewen Hydro Scheme ¯ Designated Sites Plan - Cable Route Central South

Key: Development Site Boundary Cable Route Site of Special Scientific Interest Special Area of Conservation Special Protection Area

0 250 Meters

Date: 19/06/2017 Scale: 5,000 Afon Claewen Hydro Scheme ¯ Designated Sites Plan - Cable Route Central North

Key: Development Site Boundary Cable Route Site of Special Scientific Interest Special Area of Conservation Special Protection Area

0 250 Meters

Date: 19/06/2017 Scale: 5,000 Afon Claewen Hydro Scheme ¯ Designated Sites Plan - Cable Route Northeast

Key: Development Site Boundary Cable Route Site of Special Scientific Interest Special Area of Conservation Special Protection Area

0 250 Meters

Date: 19/06/2017 Scale: 5,000 Afon Claewen Hydro Scheme

SI SI SI SI ¯ Phase 1 Habitat Map - Pipeline SI SI SI SI West

Key: D D D D D D D D . Target note D D D D D D D D Running water Acid grassland Building |||| |||||||| ||||Continuous bracken |||| |||||||| ||||Dam Dry dwarf shrub heath Flush I I I SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Improved grassland

¯ Phase 1 Habitat Map - Pipeline East

Key: .I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I I I I I I I I I I I . Target note I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Running water SI SI SI SI 5 SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Acid grassland SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI I I I I I. I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Building I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I I I I I I I I I I I |||| |||||||| ||||Continuous bracken | | | || | | |Dam I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I I I I I I I I I I I || || || || I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Dry dwarf shrub heath SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Flush I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I SII SII ISI I I I I I I I I I I I Improved grassland

Date: 12/06/2017 Scale: 5,000 Afon Claewen Hydro Scheme

¯ Phase 1 Habitat Map - Cable Route Southwest

Key: . Target note SI SI SI SI SI SI SI SI Running water SI SI SI SI SI SI SI SI Acid grassland Building SI SI SI SI SI SI SI SI |||| |||||||| ||||Continuous bracken SI SI SI SI SI SI SI SI |||| |||||||| ||||Dam SI SI SI SI SI SI SI SI Dry dwarf shrub heath Flush SI SI SI SI SI SI SI SI I I I Improved grassland

SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI

SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Afon Claewen Hydro Scheme

¯ Phase 1 Habitat Map - Cable Route Central North

Key: . Target note Running water Acid grassland SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Building SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI 10 |||| |||||||| ||||Continuous bracken SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI . |||| |||||||| ||||Dam Dry dwarf shrub heath SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI ! ! ! ! ! ! ! ! ! ! Flush ! ! ! ! ! ! ! ! ! ! I I I SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Improved grassland ! ! ! ! ! ! ! ! ! !

SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Crown copyright and database rights 2017. Ordnance Survey 0100031673 SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Date: 12/06/2017 Scale: 5,000 SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI

SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI

SI SI SI SI SI SI SI SI SI SI SI SI SI SI SI Afon Claewen Hydro Scheme

¯ Phase 1 Habitat Map - Cable Route Northeast

Key: . Target note Running water I I I I I I < < < Acid grassland

! ! ! ! !Marshy grassland ! ! ! ! !Mixed semi-natural woodland ! ! ! ! ! Plantation coniferous woodland Rock exposure D D D DRunning water D D D DScattered bracken D D D D SI SI SISemi-improved acid grassland SI SI SISemi-improved grassland Semi-natural broadleaved woodland SI SI SI Standing water Track/ Car park Wet modified bog 0 250 Meters

Date: 12/06/2017 Scale: 5,000 Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Appendix A – Layout Drawings

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Appendix B –BIS Protected Species Results

Scientific Name Common Name Taxon Group Plecotus auritus Brown long-eared bat Mammal Pipistrellus pipistrellus Common pipistrelle Mammal Myotis brandti Brandt's bat Mammal Myotis mystacinus Whiskered bat Mammal Pipistrellus pygmaeus Soprano pipistrelle Mammal Myotis daubentonii Daubenton’s bat Mammal Meles meles Badger Mammal Lepus europaeus Brown hare Mammal Erinaceus europaeus European hedgehog Mammal Mustela erminea Stoat Mammal Linaria cannabina Linnet Bird Phoenicurus ochruros Black redstart Bird Melanitta nigra Common scoter Bird Chroicocephalus ridibundus Black-headed gull Bird Bucephala clangula Goldeneye Bird Passer domesticus House sparrow Bird Cuculus canorus Cuckoo Bird Phylloscopus sibilatrix Wood warbler Bird Turdus philomelos Song thrush Bird Loxia curvirostra Red crossbill Bird Milvus milvus Red kite Bird Prunella modularis Dunnock Bird Pyrrhula pyrrhula Bullfinch Bird Sturnus vulgaris Starling Bird Muscicapa striata Spotted flycatcher Bird Turdus iliacus Redwing Bird Turdus viscivorus Mistle thrush Bird Turdus pilaris Feildfare Bird Poecile montanus Willow tit Bird Poecile palustris Marsh tit Bird Lagopus lagopus Red grouse Bird Turdus torquatus Ring ouzel Bird Dryobates minor Lesser spotted woodpecker Bird Alcedo atthis King fisher Bird Aythya marila Scaup Bird Emberiza schoeniclus Reed bunting Bird Emberiza citrinella Yellowhammer Bird Fringilla montifringilla Brambling Bird Ficedula hypoleuca Pied flycatcher Bird Tyto alba Barn owl Bird Accipiter gentilis Goshawk Bird 31

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Scientific Name Common Name Taxon Group Falco Subbuteo Hobby Bird Caprimulgus europaeus Nightjar Bird Coccothraustes coccothraustes Hawfinch Bird Calidris maritima Purple sandpiper Bird Alauda arvensis Skylark Bird Acanthis cabaret Lesser redpoll Bird Falco peregrinus Peregrine falcon Bird Falco tinnunculus Kestrel Bird Anthus trivialis Tree pipit Bird Numenius arquata Curlew Bird Lasiommata megera Wall Butterfly Synanthedon scoliaeformis Welsh clearwig Butterfly Coenonympha pamphilus Small heath Butterfly Boloria selene Small pearl-bordered fritillary Butterfly Hipparchia semele Grayling Butterfly Lasiommata megera Wall Butterfly Agrochola helvola Flounced chestnut Moth Spilosoma lubricipeda White ermine Moth Bena bicolorana Scarce silver-lines Moth Ceramica pisi Broom Moth Acronicta rumicis Knot Grass Moth Mniotype adusta Dark brocade Moth Chiasmia clathrate Latticed heath Moth Ecliptopera silaceata Small phoenix Moth Timandra comae Blood-vein Moth Cymatophorima diluta Oak Lutestring Moth Perizoma albulata Grass rivulet Moth Ennomos erosaria September thorn Moth Ennomos quercinaria August thorn Moth Watsonalla binaria Oak hook-tip Moth Lycia hirtaria Brindled beauty Moth Cosmiotes stabilella Southern dwarf Moth Scotopteryx chenopodiata Shaded broad-bar Moth Spilosoma lubricipeda Dusky brocade Moth Diarsia rubi Small square-spot Moth

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Scientific Name Common Name Taxon Group Hoplodrina blanda Rustic Moth Epirrhoe galiata Galium Carpet Moth Allophyes oxyacanthae Green-brindled Crescent Moth Chesias legatella Streak Moth Tyria jacobaeae Cinnabar Moth Eugnorisma glareosa Autumal rustic Moth Eulithis mellinata Spinach Moth Atethmia centrago Centre-barred sallow Moth Brachylomia viminalis Minor Shoulder-knot Moth Xestia castanea Neglected rustic Moth Stilbia anomala Anomalous Moth Leucania comma Shoulder-striped wainscot Moth Tholera cespitis Hedge Rustic Moth Euxoa tritici White-line dart Moth Hemistola chrysoprasaria Small Emerald Moth Melanchra persicariae Dot Moth Arctia caja Garden tiger Moth Tholera decimalis Feathered Gothic Moth Orthosia gracilis Powdered quaker Moth Asteroscopus sphinx Sprawler Moth Deileptenia ribeata Satin beauty Moth Eupithecia virgaureata Golden-rod pug Moth Lampropteryx otregiata Devon carpet Moth Dioryctria abietella Dark pine knot-horn Moth Nemapogon clematella Barned white clothes Moth Mompha langiella Clouded cosmet Moth Evergestis pallidata Chequered pearl Moth Xanthorhoe ferrugata Dark-barred twin-spot carpet Moth Timandra comae Blood-vein Moth Spilosoma luteum Buff ermine Moth Amphipoea oculea Ear Moth Orthonama vittata Oblique carpet Moth Hyacinthoides non-scripta Blue bell Plant Vicia orobus Wood bitter vetch Plant Gymnadenia conopsea Fragrant orchid Plant Pulmonaria officinalis Lungwort Plant Hamatocaulis vernicosus Varnished hook-moss Moss Lycopodium clavatum Stags horn clubmoss Moss Punctelia jeckeri Green foliose Lichen Lobaria virens Lobaria virens Lichen Caloplaca lucifuga Caloplaca lucifuga Lichen Bacidia circumspecta Bacidia circumspecta Lichen Salmo trutta Brown trout Fish

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Appendix B – Phase 1 Habitat Survey Target Notes and Species List

Target Note Description 1 Small stream associated with the traditionally laid hedgerows 2 Small stream associated with the traditionally laid hedgerows Stand of mature trees including sycamore, horse chestnut and beech, all with bat roost potential features. 3 Small drainage ditch running adjacent to the track and the semi-improved grassland. 4 Disused mine surrounded by broadleaved trees 5 Defunct old stone wall running adjacent to the track. 6 Stand of trees – Sycamore, horse chestnut, beech species 7 The habitat surrounding the building is very wet, south of the road there is an abundance of mat forming Sphagnum sp. including an abundance of soft rush. 8 Line of trees associated with riparian corridor, species consist of Salix sp. 9 The road verge habitat is consistent with that of semi-improved grassland, bracken is also present within the species composition. 10 Public footpath with shrub and bramble

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Appendix C – Photographic Plates

Pipeline route

Photograph 1: Area of improved grassland where proposed power house will be located. Photograph also shows plantation coniferous woodland to the south of the track and proposed pipeline route and the riparian broadleaved woodland to the north.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 2: The defunct species poor hedge that flanks a small slow flowing stream.

Photograph 3: Area of improved grassland pipeline will traverse that is dominated by rush species.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 4: Improved grassland and hedgerows with associated streams that the pipeline will traverse once leaving the track and directing down to the river Claerwen and powerhouse.

Photograph 4: Stand of broadleaved woodland north of the track and proposed pipeline route.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 5: Typical area of acid grassland that the pipeline route will traverse

Photograph 6: Area of modified bog (degrading) where the intake construction compound is to be located.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 6: Old stone building with willow species and modified bog and semi-improved grassland.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 7: Area of flush within the semi-improved grassland.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 8: Small stream located to the east of the defunct old stone buildings that runs from north to south into the River Claerwen.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 9: Example of marshy grassland dominated by purple moor grass that is to the north and south of the track and the proposed pipeline route.

Cable route

Photograph 10: Road and semi-improved grassland the cable route will traverse.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 11: Public footpath where the proposed cable route leads through dry heath and acid grassland mosaic.

Photograph 12: Public footpath and proposed cable route through dry heathland.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 13: Area of broadleaved woodland leading down to road east of the proposed cable route.

Photograph 14: Area where coniferous forest has been clear felled, habitat is that of dry heath and acid grassland, more dominated by grasses.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 15: Forestry track and cable route through coniferous woodland to the east and broadleaved woodland to the west.

Photograph 16: Forestry track through clear-fell forest and coniferous forest.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 17: Public footpath and proposed cable route leading off forestry track down to the main road.

Photograph 18: Cable route to traverse bridge.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 19: Public footpath south west of road adjacent to the Caban-coch Reservoir.

Photograph 20: Road and proposed cable route with heathland to the west and the public footpath with verges and the Caban-coch reservior to the east.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Photograph 21: Public footpath with associated verges.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Appendix D – Dust Management Plan Information

A Dust Management Plan (DMP) will be developed and implemented. The specific receptor is the oak woodland including the bryophyte, liverwort and lichen species present along the cable route. Solid screens or barriers around dusty activities at least as high as any stockpiles will be erected. Specific operations such as concreting, subsoil excavation etc will be fully enclosed within the designated sites. Barriers and site fencing will be cleaned weekly using wet methods. All materials will be removed from the designated site and covered. Smaller stockpiles within the working width will be covered when not in use to prevent wind whipping.

All vehicles will switch of engines when stationary to prevent idling vehicles. Diesel and powered generators will be avoided with mains electricity or battery powered equipment used as far as practically possible. A signpost system imposing a maximum speed limit of 10 mph will be employed throughout the construction zone (regardless of designated sites) to reduce dust and emissions to adjoining habitats.

Cutting, grinding and sawing equipment will be fitted or used in conjunction with suitable dust suppression techniques such as water sprays or local extraction (e.g. suitable local exhaust ventilation systems). An adequate water supply will be installed for effective dust suppression and mitigation, likely via a bowser on towed by 4x4 or similar. There will be no skips at the trenching locations near the woodlands of concern. Drop heights from loading shovels, hoppers and excavators will be minimised and use of fine water spray implemented. Clean-up equipment will be located within the working width to deal with dry spillages using wet cleaning methods.

Excavations and temporary earthworks to be stabilized using hessian or trackifers where ground is exposed. Small working areas approach will be taken to reduce exposure of soils to air where possible.

Sand, aggregates and bulk cement are to be delivered in enclosed vehicle units and stored with suitable emission control to prevent escape of material and overfilling during delivery. Or where bags are used, ensure they are maintained in sealed bags and stored in the materials/construction compound.

Where trackways and trackouts are located these are to be maintained using water assisted dust sweeper(s) or similar. This will also apply to access road and local roads, to remove, as necessary, any material tracked out of the site. This may require a sweeper being in constant use for certain parts of the construction route. No dry sweeping of large areas will be permitted. Vehicles entering and leaving site carrying materials will be fitted with covers to prevent escape. A wheel washing system will be implemented with rumble grids to dislodge accumulated dust and mud prior to entering or leaving the designated site area as well as the development site itself.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Appendix E – Twyi and Claerwen Invertebrate Survey: Technical Note

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Appendix F – Grassland/Heath Extraction and Restoration Method

Marshy grassland is reliant on the hydrological properties of the underlying soils. Therefore, a methodology for extracting the existing marshy grassland turf and subsoils is described:

• Cut or mow grassland collecting arising (this is needed so that the vegetation is short when turves are cut which gives them a better success rate and makes them easier to transport). • Erect stock proof fencing around the working width. • Erect silt fencing along each side of the strip area (10m width) and internal drifts at 50m intervals to arrest suspended silts from the stripped area being washed into the surrounding areas of retained or yet to be lifted turf areas – the internal drifts will be removed as the turf lifting reaches them. • A conventional 13t tracked excavator will work in conjunction with a SPIDER excavator or similar to lift and place the turves from the strip area into the wet storage cell. The storage cell will be made from rigid plastic driven/dug into the ground to form a bunded environment to place turves. The cell will be maintained as wet by installing a trickling water pump to maintain water volume supporting the vegetation. Soils will be stored either side of the corridor. Both machines are to be fitted with Engcon Tiltrotator and specialist turve cutting attachments. • Following turf removal any topsoil remaining on the ground will be scraped off to one side of the strip area for storage. • Excavate trench, store excavated subsoil to one side of the working width in wet cell. • Install pipeline and intake chambers. • Backfill with subsoil with no or light compacting to replicate pre-excavation state • Replace topsoil and turf

Once the subsoil and topsoil is replaced the reinstatement of the turf can begin without having to wait for the remainder of the trench section to be completed. Replacement of the turf will be completed within three days of subsoil re-fill. A team of ground workers will work behind the turf replacement machines back filling by hand any voids around the turf joints.

Practical benefits of the methodology include:

• A linear working progression over the corridor minimizes machinery traffic and all work will be conducted from the stripped surfaces so removing the risk of compaction. • Only two parallel cut lines required that should become indistinct within weeks of completion. • Use of water fed detainment cell(s) to maintain water volume in vegetation dependent soil.

Dry heath/ acid grassland mosaic Areas of existing heather Calluna vulgaris and bilberry Vaccinium myrtillus cover to be re-seeded from a local donor site. On completion of the works to the intake weir and chamber retained young plants to be re-planted along the edge of the access track and further seed spread on remaining open patches of ground. The rock is close to the surface along the top of this area and so planting will be sparse initially but natural regeneration encouraged as soil begins to build around the young plants. Spreading of wavy-hair grass deschampsia flexuosa and bent grass Agrostis capillaris seeds can be implemented as companion grasses to fill gaps and encourage a mosaic habitat. The planting of seedlings and spreading of seed will be undertaken during spring (April-May) to encourage establishment before a winter period. Application of seeds would be at 600-1000g/m2. Direct planting of heathland species will be at 10-15 plants/m2.

Afon Claerwen Hydro Scheme Preliminary Ecological Appraisal

Seed harvesting can be undertaken from the local area using a donor site. Further details would need to be developed with Natural Resources Wales to agree a donor site. The land would need to be relatively flat to allow the harvesting machine access heathland to collect common heather. Cutting/collection would take place between October and December when the majority of seed capsules are mature.

Areas of removed bracken will be seeded with heath plants harvested from the local area. To maintain bracken control, cutting will take place when the plants reserves are at their lowest throughout June, July and August using hand tools. Herbicide treatment is to be avoided without prior agreement of Natural Resources Wales and should only be considered where extensive areas of heather has re- colonised.