Alwen Forest Wind Farm Grid Connection
Scoping Report
Ffon 19 November 2019
1204855
Innogy Renewables UK Ltd
Document history
Author Janet Sanders, Project Manager 27.09.19 Checked Ffion Edwards, Senior Project 27.09.19 Manager Approved John Woodruff, Technical 30.09.19 Director Client Details
Contact Martin Cole Client Name Innogy Renewables UK Ltd Address Baglan Bay Innovation Centre, Central Avenue, Baglan Energy Park, Port Talbot SA12 7AX Issue Date Revision Details A 30.08.19 First revision of scoping report B 30.09.19 First Draft to innogy C 17.10.19 Second revision to innogy D 24.10.19 Submission to NRW and WW E 19.11.19 Final submission to PINS
NATURAL POWER CONSULTANTS LIMITED, THE NATURAL POWER CONSULTANTS LIMITED, NATURAL POWER SARL, NATURAL POWER CONSULTANTS (IRELAND) LIMITED, NATURAL POWER LLC, NATURAL POWER S.A, NATURAL POWER SERVICES LIMITED AND NATURAL POWER OPERATIONS LIMITED (collectively referred to as “NATURAL POWER”) accept no responsibility or liability for any use which is made of this document other than by the Client for the purpose for which it was originally commissioned and prepared. The Client shall treat all information in the document as confidential. No representation is made regarding the completeness, methodology or current status of any material referred to in this document. All facts and figures are correct at time of print. All rights reserved. VENTOS® is a registered trademark of NATURAL POWER. Melogale™, WindCentre™, ControlCentre™, ForeSite™, vuWind™, WindManager™ and OceanPod™ are trademarks of NATURAL POWER.
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Contents
1. Introduction ...... 1 2. Purpose of the Scoping Report ...... 1 3. The Applicant ...... 2 4. The Proposed Alwen Forest Grid Connection ...... 3 4.1. Wind Farm and Grid Connection ...... 3 4.2. Grid Connection Route Selection ...... 4 4.3. Preferred Grid Connection Routes ...... 6 4.4. Grid Connection Options ...... 6 4.5. Operational Period ...... 10 4.6. Decommissioning ...... 11 5. Approach to the Environmental Impact Assessment (EIA) ...... 11 5.1. EIA Steps ...... 11 5.2. What the EIA will Assess ...... 12 5.3. Gathering Baseline Information...... 12 5.4. Prediction and Evaluation of Impacts and Effects ...... 12 5.5. Cumulative Effects ...... 13 5.6. Mitigation and Monitoring of Environmental Effects ...... 13 6. Legal and Policy Context ...... 14 7. Environmental Statement ...... 15 8. Embedded Mitigation and Further Layout Iterations ...... 16 9.1. Introduction ...... 17 9.2. Methodology...... 17 9.3. Survey Work...... 18 9.4. Results ...... 19 9.5. Discussion ...... 21 9.6. Conclusions...... 22 10.1. Introduction ...... 22 10.2. Methodology...... 22 10.3. Survey Work...... 24 10.4. Results ...... 25 10.5. Discussion ...... 26 10.6. Conclusions...... 27 11. Landscape and Visual ...... 27 11.1. Introduction ...... 27 11.2. Planning Policy...... 28 11.3. Grid Connection Route Corridors ...... 29 11.4. Methodology...... 29 11.5. Cumulative Assessment...... 35 12. Hydrology, Geology and Hydrogeology ...... 35 12.1. Introduction ...... 35 12.2. Assessment Methodology ...... 36 12.3. Desk Based Studies ...... 40 12.4. Impact Assessment ...... 44 13. Cultural Heritage ...... 45
Alwen Forest Wind Farm Grid Connection
13.1. Introduction ...... 45 13.2. Environmental Baseline and Potential Sources of Impact ..... 45 13.3. Method of Assessment...... 46 14. Traffic and Transport ...... 52 14.1. Introduction ...... 52 14.2. Methodology...... 52 15. Noise ...... 54 15.1. Introduction ...... 54 15.2. Legislation and Guidance ...... 54 15.3. Noise Sensitive Receptors ...... 55 15.4. Construction Noise Effects ...... 55 15.5. Operational Noise Effects ...... 56 16. Forestry ...... 57 16.1. Introduction ...... 57 16.2. Consultation ...... 58 16.3. Legislation and Guidance ...... 58 16.4. Methodology...... 58 17. Socio-Economics ...... 59 17.1. Introduction ...... 59 17.2. Methodology...... 60 17.3. Impact Assessment ...... 60 18. Health and Public Safety ...... 60 18.1. Lightning...... 60 18.2. Health & Safety ...... 61 18.3. Impact Assessment ...... 61 19. Aviation and Existing Infrastructure ...... 61 19.1. Introduction ...... 61 19.2. Other Existing Infrastructure ...... 62 19.3. Impact Assessment ...... 63 20. Summary, Residual and Synergistic Effects and Mitigation ...... 63 21. ES Accompanying documentation ...... 63 22. Responding to the Scoping Report ...... 64
Appendix A: Grid Matrix ...... 65
Figures ...... 66
Alwen Forest Wind Farm Grid Connection
1. Introduction
This scoping report has been prepared by Natural Power Consultants Limited (Natural Power) on behalf of Innogy Renewables UK (innogy). This report is in anticipation of an application for a Development of National Significance (DNS) for a proposed wind farm development, including grid connection, approximately 4 km north of Cerrigydrudion within Conwy County Borough Council (CCBC) and Denbighshire County Council (DCC).
As of April 2019, all energy generation projects between 10 MW and 350 MW, including overhead electric lines of up to 132 kV which are associated with a devolved generation station, are considered a DNS project.
Under the statutory procedures set out in The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017 (EIA Regulations) it is proposed that any such application is accompanied by an Environmental Statement (ES).
This scoping report is specifically for the grid connection to the proposed Alwen Forest Wind Farm. A scoping report for the Alwen Forest Wind Farm has already been submitted to the Planning Inspectorate and a scoping direction was received on 27/09/2018 (reference no. 3208218). The applicant intends to submit one planning application and one EIA which addresses the wind farm and the selected grid connection.
This scoping report has been prepared to identify the likely significant environmental effects of the proposed indicative grid connection which will need to be assessed in detail in the Environmental Impact Assessment (EIA) and reported within the ES, which will accompany the planning application. This scoping request is made in relation to a Development of National Significance for the purposes of section 62D of the Town and Country Planning Act 1990.
2. Purpose of the Scoping Report
The purpose of this scoping report is to provide sufficient information for consultees to agree the scope of the EIA for the grid connection. Information has been provided on what the applicant intends to assess within the EIA and report on in the ES. Where the applicant is proposing to ‘scope out’ particular elements, sufficient information and justification has been provided in this report. The intention is to ensure that the focus of the ES is on any receptors impacted by the proposed development that may experience significant effects.
Consultees will note that the scoping report contains a number of specific questions against which responses would be appreciated. Not all questions will be relevant to all consultees; therefore, we request that consultees provide feedback only on those questions appropriate to them. The questions should not be considered an exhaustive list, and consequently, consultees are invited to provide further responses on any issue they consider relevant to the proposed development. If consultees elect not to respond, innogy will assume that consultees are satisfied with the proposed approach.
Stakeholder Consultation The applicant and its competent experts, as well as stakeholders and consultees, have a sound understanding of the proposed development area from the work at Alwen Forest Wind Farm and other adjacent wind farms.
Natural Power and innogy consider consultation with statutory and non-statutory consultees as an integral part of the iterative EIA process and recognise the benefits in carrying out early consultation with all concerned parties. The consultation will progress with the circulation of this scoping report and will continue for the duration of EIA process.
Alwen Forest Wind Farm Grid Connection 1
This report utilises the existing information, experience from undertaking EIA at adjacent wind farms and data gathered to date to identify key receptors and likely significant effects to be agreed with consultees. Other minor and non-significant issues will be scoped out, and thus not included within the final submission in the ES.
By engaging with key consultees at an early stage via this scoping report it is intended that the eventual ES submitted should be streamlined focussing only on likely significant effects. The applicant will ensure that regular and continued liaisons with key stakeholders (including the community) are carried out and documented to agree the assessment baseline, methodology and thus, the EIA process and final ES documents will be proportionate yet robust.
Question 1: Do the consultees have any comments about the proposed approach to scoping and the purpose of the scoping report?
Community Consultation Natural Power and innogy believe that public consultation is important throughout the development of a renewable energy project. As this is a Development of National Significance project there is a requirement under article 11 of the Developments of National Significance (Procedure) (Wales) Order 2016 that a DNS application must be accompanied by a Pre-Application Consultation report.
The community within the area surrounding the proposed development will be consulted. This is anticipated to include meetings and information events in local community venues such as village halls and will allow local residents an opportunity to view and discuss the proposal, provide comments and ask any questions. English and Welsh speaking staff will be on hand as well as bilingual written information. The events will be timed to allow any concerns to be raised and potentially addressed in the final design of the wind farm and grid connection route. The project website will also be updated as development progresses. Contact details for the project will be made available on the website and shared in the local community including a dedicated project email address to field any queries and ensure two-way communications.
Question 2: Do consultees have any comments in relation to the proposed approach to community consultation?
3. The Applicant
Innogy Renewables UK Limited (innogy), develops, builds and operates projects to generate power and extract energy from renewable sources. It is part of Innogy SE; an established European energy company which was formed from the restructuring of the RWE Group and started operations on 1 April 2016. Innogy has ten offices across the UK and involvement in 2,000 MW of renewable energy capacity. In the UK, innogy currently operates 18 onshore wind farms, 4 offshore wind farms and 24 hydroelectric sites.
Innogy has a significant history of developing renewable energy infrastructure in Wales, having built the UK’s first commercial offshore wind farm in Wales in 2003 at North Hoyle. Innogy has four offices across Wales (Baglan, Mostyn, Llanidloes and Dolgarrog) and employs 138 permanent or fixed term members of staff. Innogy currently operates three offshore wind farms and six hydroelectric power stations across Wales, with three onshore wind farms, namely Clocaenog Forest in North Wales (96 MW), Mynydd y Gwair near Swansea (32.8 MW) and Brechfa Forest West in Carmarthenshire (57.4 MW). These three onshore wind farms alone amount to a total capital investment of circa £272 million and a green pipeline of 186 MW of renewable energy. These three wind farms invest a further ~£1.4 million each year into the surrounding communities through their associated Community Investment Funds. Innogy has a 20-year track record of investing in the communities that surround its developments and in 2017 renewable energy projects operated by innogy invested over £900,000 into community projects across Wales.
Alwen Forest Wind Farm Grid Connection 2
The innogy team was able to use its local knowledge derived from the development of the Clocaenog Forest and offices in North Wales to assist its consideration of feasibility and design of the Alwen Forest Wind Farm and grid connection.
4. The Proposed Alwen Forest Grid Connection
4.1. Wind Farm and Grid Connection Alwen Forest Wind Farm lies within commercial forestry and is part of the Dŵr Cymru Welsh Water estate leased to Natural Resources Wales (NRW). The majority of the wind farm site is located within Conwy County Borough Council (CCBC) local authority area, with a small part of the proposed site boundary within the neighbouring Denbighshire County Council (DCC) local authority area. The preferred grid connection corridor(s) lies within DCC and CCBC local authority areas.
Technical Advice Note 8 (Planning for Renewable Energy), published in 2005, was prepared by the Welsh Government, identifying seven areas in Wales suitable for large scale wind farm developments. The Alwen Forest Wind Farm and proposed grid connection are located within Technical Advice Note 8, Strategic Search Area A, as shown on Figure 2.1 - Regional Context. The National Development Framework (NDF) produced by Welsh Government, is currently out for consultation. The NDF is a 20-year development plan (2020-2040) that will cover the whole of Wales to show where nationally significant developments, infrastructure and services like energy, transport, water and waste projects should best take place. The NDF is expected to be adopted in September 2020 and the EIA for Alwen Forest Wind Farm and Grid Connection will refer to the latest legislation at the time of submission.
The proposed wind farm development will comprise up to nine wind turbines, up to 200 m to tip in height. It is expected that the turbines will each be 3 Mega Watt (MW) or greater in capacity, with a total site capacity possibly of up to 33 MW. See Figure 2.2 for proposed Alwen Forest Wind Farm layout.
The wind turbines at the proposed Alwen Forest Wind Farm would produce electricity at 690 - 1000 Volts each. The electricity would then be transformed to 33,000 Volts (33 kV) via a transformer likely to be located immediately adjacent to the base of the tower of each turbine, however it could be positioned within the tower or nacelle, depending on the final turbine model used. The transformers would be linked to the on-site substation via high voltage underground cables placed in trenches, which would generally be adjacent to and alongside the on-site access tracks. From the on-site substation a grid connection would link to the wider electricity distribution network.
Figure 2.4 shows a potential location for an on-site ‘proposed substation and energy storage’, which has been influenced by the two grid route corridors which are the subject of this scoping report. The final location for the on-site substation will be determined through detailed site assessment undertaken during the EIA phase. A separate connection to the wider distribution grid network has been secured at the existing Scottish Power Energy Network’s Clocaenog substation located to the north-east of the site (see Figure 2.4), maximising use of the remaining spare capacity on the 132 kV connection to St Asaph. This is likely to be the lowest cost option for connection to the grid and as an existing point of connection could help minimise the environmental impact. Whether the grid connection would be overhead line or underground cable, or a combination is still under consideration and will be dependent on engineering, environmental and economic factors.
This scoping report is presented specifically for a grid connection for Alwen Forest Wind Farm. The connection would enable the proposed wind farm development to respond to Welsh Government’s commitment to decarbonising electricity generation with a target of 70% of Wales’ electricity demand to be met from renewable sources by 2030. The Alwen Forest proposed development maximises the potential of this site to deliver on these objectives and will be designed in such a way as to balance society’s needs for efficient sustainable energy generation with the relevant environmental considerations.
Alwen Forest Wind Farm Grid Connection 3
4.2. Grid Connection Route Selection The objective of route selection is to identify a technically feasible and most economically viable grid connection route between specified points, whilst minimising disturbance to people and the environment where possible. An iterative approach is followed which engages with stakeholders and establishes a balance between economic viability, land use and the environment.
Overhead lines and underground cables have technical requirements which influence their routeing and siting. This is further discussed in sub-section 4.4. The indicative grid connection routes will be assessed for their potential environmental impacts consistent with Environmental Impact legislation relevant to Wales.
The following key considerations have been taken into account during the design process of the Alwen Forest Wind Farm grid connection: • Relationship to the surrounding landscape; • Relationship with cumulative developments; and • Technical and other environmental constraints.
The first stage in the iterative process of route selection was the commissioning, by innogy of a grid route study carried out by Atkins. Atkins identified five routes on technical viability alone. A further two potential grid connection routes were identified, by innogy following an initial review of the Atkins study. The seven identified connection routes were not specified in terms of being wholly or partially underground cables or overhead lines (OHL). Subsequent to the completion of the report, innogy’s environmental consultancy team reviewed the seven routes. Informed by desk-based environmental constraints mapping, knowledge of the environmental sensitivities present in the adjoining Clocaenog Forest Wind Farm site and with reference to the relevant Holford Rules1 and other relevant policy and guidance, each of the routes were reviewed for their likely environmental impacts. Consideration was made on the suitability and acceptability for overhead line and undergrounding accepting that this will be assessed further as part of the detailed design process.
A workshop attended by the environmental consultant team on the 6th August 2019 was held to consider the environmental performance of the seven routes. This led to the elimination of some routes and the emergence of the two favoured indicative grid connection corridors, Corridor 1 and Corridor 2 shown on Figure 2.4. Alwen Forest Wind Farm: Grid Corridors.
A brief summary of all seven routes is provided below, along with a brief reasoning behind their omission or selection as preferred routes. Further detailed information on the appraisal of each route can be found
1 The Holford Rules (applicable to Overhead Lines). 1. Avoid altogether, if possible, the major areas of highest amenity value, by so planning the general route of the line in the first place, even if the total mileage is somewhat increased in consequence. 2. Avoid smaller areas of high amenity value or scientific interest, by deviation; provided that this can be done without using too many angle towers (i.e. the more massive structures which are used when lines change direction). 3. Other things being equal, choose the most direct line, with no sharp changes of direction and thus fewer angle towers. 4. Choose tree and hill backgrounds in preference to sky background wherever possible and when the line has to cross a ridge, secure this opaque background as long as possible and cross obliquely when a dip in the ridge provides an opportunity. Where it does not, cross directly, preferably between belts of trees. 5. Prefer moderately open valleys with woods, where the apparent height of the towers will be reduced and views of the line will be broken by trees.
6. In country which is flat and sparsely planted, keep the higher voltage lines as far as possible independent of smaller lines, converging routes, distribution lines and other masts, wires and cables so as to avoid a concatenation or 'wirescape’.
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in Appendix A: Alwen Grid Options Matrix of this scoping report. Figure 2.3 ‘Alwen Forest Wind Farm Grid Connection Routes shows the location of the original seven routes.
North 1 This route extends 8.8 km in length and runs north of Llyn Brenig. The route would utilise the proposed northern substation location in the Alwen Forest Wind Farm. At its eastern end the route partly runs through the Tir Mostyn and Foel Goch operational wind farms. The majority of the route follows the B4501 through the Mynydd Hiraethog Site of Special Scientific Interest (SSSI). The route would connect to the SPEN Clocaenog Substation. This route was dismissed during the workshop due to its potential impacts on landscape and ecology receptors.
North 2 This route extends 8.17 km in length and is similar in its alignment as North 1, however instead of following the B4501 to the north-west of Llyn Brenig, it crosses through the centre of the open moorland. Approximately 4.7 km of the route crosses the Denbigh Moors Registered Historic Landscape. This route was dismissed due to its potential impacts on landscape and ecology receptors.
South 1 This route extends 10.4 km in length and follows tracks within Clocaenog Forest for the majority of the route, south of Llyn Brenig. The tree clearance necessary to accommodate the route (if underground routeing is deployed) has already largely occurred when corridors for the forestry operations beside the tracks were created. The route’s alignment is to the east of a ridgeline that is occupied by the Tir Mostyn Wind Farm. Along its southern section, the route crosses the mid-slopes of the Afon Brenig valley to the south of Llyn Brenig. Within the proposed Alwen Forest Wind Farm, the route connects to the proposed southern substation.
South 2 This route extends 8.57 km in length and approximately 1.6 km of the route crosses moorland comprising relatively remote and open character that is particularly valued for its heathland habitat and is designated as a SSSI (Mynydd Hiraethog). It is also designated open access land with a bridleway crossing centrally. The route crosses the Clwydian Way long-distance route where it runs within Clocaenog Forest. The route runs along the southern edge of Llyn Brenig and along the top of the reservoir dam where it partly follows the Clwydian Way. The route corridor includes a scheduled monument and runs close to another. Within the proposed Alwen Forest Wind Farm, the route connects to the proposed southern substation. This route was dismissed due to its potentially high impacts on landscape, cultural heritage and ecology receptors.
South 3 This route extends to 8.48 km in length and follows the same alignment as South 2 apart from the southern section where it is located further south of the dam wall along a minor road. It would connect to the proposed Alwen Wind Farm southern substation. Potential impacts on landscape and cultural heritage will need to be considered if this route was taken forward.
Route A This route extends 10.2 km in length and is similar in its alignment to South 1 apart from small sections that deviate in the north and south. The northern deviation crosses a gully close to the Clocaenog substation. The southern deviation follows a road before entering the forestry. The route also crosses the Afon Brenig valley to the south of Llyn Brenig, at the foot of the dam embankment. Cultural assets in proximity include Hafoty Wen Ring Cairn and Pont-y-Rhuddfa Grade II listed building. The route would connect to the proposed southern substation.
Alwen Forest Wind Farm Grid Connection 5
Route B This route extends 9.67 km in length and largely similar to Route A apart from a section that runs to the south west of Llyn Brenig. The route leaves the road south of the dam and runs to the south west through the Isgaer-Wen plantation, following a forestry track before re-joining Route A. It connects to the proposed southern substation.
4.3. Preferred Grid Connection Routes The preferred grid connection corridors identified on Figure 2.4 ’Alwen Forest Wind Farm: Grid Corridors’ extend from the existing SPEN Clocaenog Substation to the proposed Alwen Forest Wind Farm southern substation. The corridors are derived from a combination of sections of Route A, South 1, South 2, South 3 and Route B (now labelled as Corridor 1 and Corridor 2). They represent those sections of the Atkin’s routes corridors with the least potential for significant environmental effect, based upon the presence of existing designations and an understanding of the broad environmental conditions existing within the study area. Corridor 1 extends 9 km and Corridor 2 extends 9.8 km. The selection of the final grid route and the extent to which it will be wholly or partially on OHL or underground cables will be informed by detailed environmental assessment. The southern substation location is also indicative at this stage, until further assessment is undertaken.
The two preferred route corridors that emerged from the review process are described below.
Corridor 1 Corridor 1 follows a southern direction from the existing Clocaenog substation through forestry plantation, with the operational Clocaenog Forest Wind Farm to the east and the southern section of the operational Tir Mostyn and Foel Goch Wind Farm to the west. The corridor includes sections of forestry tracks south until it veers west through the Isgaer-wen plantation. The maximum topography along the route is approximately 475 m AOD, from where it descends to the south-eastern corner of Llyn Brenig where it enters open pastoral fields. The corridor includes the dam wall that contains the reservoir along its southern edge. The corridor crosses the northern extremity of the Afon Brenig (a tributary river of the River Alwen).
Corridor 2 Corridor 2 deviates from Corridor 1 and heads west further south than Corridor 1. It follows the direction of an unnamed road at approximately 400 m AOD which runs mostly through forest and partly through an open area comprising a relatively steep south facing slope overlain with pastoral fields. Corridor 2 meets Corridor 1 at the Afon Brenig with both options then continuing to the west, crossing the B4501 and terminating at a proposed southern substation in the Alwen Forest Wind Farm site. Public rights of way cross both of the corridor options.
4.4. Grid Connection Options
Overhead Lines Should the route or section of the route be mounted on overhead lines they are likely to be on 10 m single wooden poles (most likely scots pine). Figure 4.1 shows a general arrangement for overhead line poles.
Alwen Forest Wind Farm Grid Connection 6
Source: SP Energy Networks
Figure 4.1: General Arrangement Single Pol Double Crossarm Intermediate or Pin. Reproduced with the kind permission of SP Energy Networks.
Subject to detailed design it might be possible to use a single pole at terminal ends although technical factors may require a twin pole structure. Terminal ends would be located at each substation and potentially at the start and end of any underground section of the connection. Whilst the intention would
Alwen Forest Wind Farm Grid Connection 7
be to follow a connection route as straight as possible it would be necessary to deviate in order to avoid sensitive features. At points of deviation angle poles would be used. These are likely to be single pole structures although sharp deviations (>75%) may require twin pole structures. In all locations where the line deviates there would be the requirement to provide cable stays to the poles. In-line poles would not be stayed and, subject to the ground conditions, the pole types are unlikely to require foundations.
Overhead lines would require special consideration within forested areas. Currently NRW has suggested that the unplanted clearance strip within NRW forested areas increases to two times tree height for OHL when compared to underground. This means that the overall unplanted strip could be up to 140 m in width assuming a maximum 35 m tree height. In addition to the proximity of trees to the overhead line, innogy has a policy whereby they require the overhead line buffer to wind turbines to be no less than three times the rotor diameter. For the section of the proposed grid corridors within Clocaenog Forest wind turbine generators (WTG) have rotors 105 m in rotor diameter therefore the nearest an overhead line can be to a WTG will be 315 m. In general, and where the overhead line crosses any turbine access roads or public highways, increased ground clearance shall comply with HSE Guidance Note GS6 which notes that the minimum requirement for an OHL 132 kV cable must be 6.7 m above ground level. In the planning application innogy will confirm the maximum corridor width either side of the pole locations required to enable the micrositing of the poles. The total width is likely to be of the order of 20 m although this may increase in certain stretches should potential constraints suggest this may be necessary.
The length of the wooden poles is likely to be 12 m with a maximum installed height unlikely to exceed 10 m above ground given that the depth of pole below ground can be between 2.2 m to 2.4 m. Minimum ground clearance of the conductor wires would be 5.2 m extending to 6.7 m should the line cross the public highway. The OHL operators assumed minimum clearance to trees from the conductors (as opposed to the pole) is 3 m from the nearest part of the tree. The clearance distance will be increased in NRW managed forestry in line with NRW’s requirements, possibly up to140 m.
It is currently proposed to install a single circuit made up of two cables per phase. A fibre optic cable may also be installed to provide telemetry and monitoring capabilities such as fault detection. The poles would carry cross arms onto which the insulators are attached. The type of conductor wire is yet to be confirmed with different sizes potentially influencing maximum span length. For the purposes of scoping it has been assumed that a maximum span length between poles of 100 m to 110 m could be achieved. The actual span between poles will be influenced by topography, climatic conditions (such as the potential for high winds or ice-loading) and by the particular sensitivity of the environment within which the line might be located,(for example a span may need to be increased in order to straddle an area of boggy ground).
Temporary construction compounds and laydown areas may be required along the route of the OHL, should this be the chosen option. They would be sited in locations accessible from the local highway network and the intention would be to use areas of existing hardstanding where these are available.
Underground Cable Underground cables can be laid directly into a trench or placed within ducts. The most common way of laying an underground cable is to use an open cut method whereby the cable is laid directly into a trench of up to 1.5 m depth. The exact width of the trench can depend upon the final specification proposed for the cable but it can be in the region of 600 mm wide to approximately 1.5 m closer to the surface to enable access. The recommended clearance distance either side of the trench is 5 m and this creates a corridor of approximately 11.5 m. The cables are placed in the bottom of the trench in a trefoil formation with the fibre optic cable placed alongside. The excavation is then filled with sand before the remaining excavation is backfilled with the excavated material. In locations where a cable is to be laid alongside a highway cables are jointed at approximately 500 m intervals. The joint boxes are approximately 2 m deep and 2 m x 1 m.
An alternative to placing the cables directly into the trench is to use ducts within which the cables would be placed. These would also require joint bays at similar intervals to the open cut method.
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Whilst trenching is likely to be the most common means of construction, in circumstances where it is not considered appropriate an alternative approach would be to drill a conduit into which the cable ducts and/or cabling can be installed. Known as Horizonal Directional Drilling (HDD) this approach is commonly used to place cables under natural features such as rivers or man-made infrastructure such as highways. In the context of this project it has yet to be determined whether HDD will be used and this will be confirmed once the final route is selected.
HDD requires the creation of a launch site and reception pit together with a laydown area for the placement of the ducts which are subsequently pulled through the conduit. A temporary construction compound dedicated to the HDD contractor may also be required.
Construction Methodology The precise method of construction will be set out by the chosen contractor at the point of commission, however it is possible to set out the high level approach to be taken.
Overhead Line The construction phase would commence with vegetation clearance along the line of the connection. The construction of temporary access tracks to the area is not intended, unless the ground is found to be sensitive to vehicle movement in which case a temporary trackway could be installed and then removed following the completion of construction activities.
It is the intention to microsite the route to avoid the need to remove individual trees (e.g. hedgerow trees) although it is accepted that this will not be possible within the areas of commercial forestry. Any tall hedges along the route would be reduced in height to achieve necessary clearances but for the purposes of constructing an overhead line it is not proposed to remove hedges providing access can be gained to the pole locations using existing tracks/field gates. Should access need to be created then the hedges can be temporarily lifted and subsequently reinstated. Existing fences/stone walls would also be retained unless there is a requirement for access. In each case a small section of enclosure would be removed to obtain access with temporary fencing in place at the end of each construction day.
The installation of the poles would be unlikely to require the formation of temporary access tracks as innogy would propose to use existing tracks where possible. Furthermore, the vehicles used to deliver the poles and undertake the excavation of foundation holes would be capable of traversing unmade ground where required. However, if the ground is found to be sensitive to vehicle movements a temporary access track could be installed. This is likely to consist of interlocking metal or plastic panels. Typical vehicles used in construction would be an excavator/digger, a lorry or tractor and trailer to deliver the poles to site and the vans and 4x4 vehicles used by the contracted workers.
At each pole location a working area of approximately 20 m by 20 m would be required. This working area does not require surface stripping; merely it is an area temporarily fenced to protect livestock from machinery for example. Within this area a pole foundation hole is excavated, and the metal cross bar affixed to the pole whilst it is on the ground. The pole is then lifted into position and the hole backfilled with the excavated material. Spoil would not be removed from site. The requirement for alternative arrangements employing foundations is unusual and can only be confirmed once the final route is selected.
Once the poles are in place the conductor cables are strung between them. This is achieved using pulley wheels attached to the poles which pull lighter, temporary cables that in turn pull the main cables. The cables are attached to the insulators and tightened. Cabling is delivered in drums which can be towed behind a tractor or 4x4 vehicle.
If the OHL is required to cross a public road then either the road can be closed with the appropriate consents to enable the stringing to take place or a scaffolding tower can be erected.
Poles would be delivered from the supplier to identified pole store locations along the route as required.
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Underground Cable The construction of an underground cable would require a similar intensity of operation to overhead lines, with similar vehicles used to excavate the trench and deliver the cabling and ducting. The common approach is to place excavated material along one side of the excavated trench (within the 5 m clearance zone) using the other side for access. As with OHL construction, it is not intended to construct temporary haul roads to the area to be excavated, however should the ground be sensitive to vehicle movement a temporary trackway could be installed and then removed following the completion of construction activities.
Typically trenches for the direct placement of cables are dug in 500 m lengths whereas those accommodating ducts are dug in 50 m lengths. In both cases, trenches might be shored temporarily depending upon the prevailing ground conditions. As noted above, both methods require joint bays; these require wider excavation and would be approximately 2 m deep.
The use of HDD requires a launch site which is the location where the direction drill is operated and its associated equipment located. The drill rig requires a power unit and bentonite clay for lubrication. The bentonite is stored in bunded tanks. A control cab is required and depending upon the scale of operation, welfare facilities may be required. The HDD works by drilling under the feature to be crossed. A small diameter opening is created which is then widened by reaming prior to pulling through the cabling duct. The cable and fibre optic is then pulled back through the duct. Each HDD launch site requires a reception site on the opposite side of the feature. The reception site is used to store the ducts to be pulled though and it is the location from which the drilling is remotely directed.
Operation
Overhead Line During the operation phase duties are limited to resilience tree cutting – to retain clearance distances and regular inspection. Conductors and insulators have a design life of approximately 40 years.
Faults on an OHL are infrequent. When they do occur, the vehicles used are likely to be similar to those needed for the construction of the line. Fault repair is quick and relatively straightforward.
Underground Cable In the normal course of operation there is no requirement to inspect underground cables although they are regularly tested.
Construction Environmental Management Plan A Construction Environmental Management Plan (CEMP) would be created and agreed with CCBC and DCC prior to construction commencing through an appropriately worded suspensive condition in order to ensure the impacts from construction are kept to a practical minimum. The CEMP would set out the method statements for constructing the grid connection and the measures that would be undertaken by contractors to ensure good site practice with regards to construction practices and environmental management. Such measures would include for the transport and storage of potentially polluting substances such as oils and lubricants as well as waste management, for example.
Should the proposed development be consented, best practice guidelines and method statements will be adopted to ensure again that the development does not impact negatively on the local environment. Best practice guidance and mitigation will apply during the construction, operational and decommissioning phases of the grid connection.
4.5. Operational Period The lifetime of the project would be up to 35 years from commissioning to decommissioning.
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4.6. Decommissioning At least six months prior to the decommissioning of the site a Decommissioning Method Statement would be prepared and agreed with the relevant consultees. Best practice guidelines will be utilised at this time. The applicant would expect to commit to a planning condition regarding decommissioning and expected to set up a restoration fund should this development receive consent.
5. Approach to the Environmental Impact Assessment (EIA)
5.1. EIA Steps An EIA is a statutory procedure which draws together in a systematic way an assessment of the likely significant environmental effects arising from a proposed development.
As the process has numerous steps, it allows for the opportunity to ‘design out’ adverse environmental effects at an early stage through the design of the project. This of course is generally preferable to mitigation or remedy at a later stage.
An iterative design approach is already in process for this project and will continue to be adopted throughout the EIA process, which will allow the proposed development to have adopted a design that minimises impacts on the local environment and environmental resources within the area, as well as being an economically viable scheme with the ability to deliver on Welsh, UK and international renewable energy targets.
The steps taken for informing and developing the EIA process are identified in the flow diagram below:
Diagram 5.1: EIA Process
For this particular project the collection of baseline data has already begun. The baseline data, and innogy and Natural Power’s knowledge and experience of working in the area has led to many impacts to the environment along the grid route being avoided or minimised already.
The information presented within this scoping report should be sufficient for the consultees to agree on those features and topics that are likely to experience a significant effect, and thus ‘scope out’ those impacts which are not considered to be significant. In doing so, the impact assessment will be focussed
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and proportionate to those effects that will influence the decision as to whether or not the project should receive consent.
5.2. What the EIA will Assess The EIA will assess the effects arising from the construction phase of the wind farm grid connection, the operational phase (which would last up to 35 years), and the decommissioning phase.
The geographical coverage of the EIA will take account of the following: • The physical extent of the proposed works; • The nature of the baseline environment and receptors, and the manner in which effects are propagated; and the • National and Local planning and policy context for the project.
5.3. Gathering Baseline Information Some of the baseline data has already been collected for this project, and the assessment team will ensure that sufficient data is obtained to enable a robust assessment, appropriate to the nature and scale of the proposed works. The extent of the baseline assessment will be determined using both professional judgement and industry best practice. The EIA will also identify areas where the baseline may change, prior to the construction and operational phases of the proposed development from current conditions (for example, maturation of landscape).
The collection of baseline data will be achieved through desk study (including the use of data gathered for the previous developments in the area), consultation, field survey and monitoring and will be clearly reported in the subsequent sections, or within the ES (should there be an expected significant effect from the development). In line with the EIA Regulations, the ES will also indicate any difficulties encountered in compiling environmental baseline conditions; such as access to land to carry out surveys where permission was not granted.
5.4. Prediction and Evaluation of Impacts and Effects The impact assessment will determine for those assessed receptors what the effect, either directly or indirectly will be from the project, by comparing the baseline conditions with the conditions that would prevail should the proposed development be constructed, operated (and decommissioned). The environmental effects of the project will be predicted in relation to environmental receptors (i.e. people), built resources and natural resources. A distinction will be made in the assessments between impacts and effects, where: • Impacts are defined as the predicted change to the baseline environment attributable to the scheme; and • Effects are the consequence of impacts on environmental resources or receptors.
The prediction of impacts examines the change to the baseline environment that could result from the construction and operation of the grid connection. The effects will be classified into one or more of the following: • Positive effects that have a beneficial influence, negative effects that have an adverse influence; • Temporary effects that persist for a limited period only, due for example to particular construction activities; • Permanent effects that result from an irreversible change to the baseline environment or which persist for the foreseeable future; • Direct effects that arise from activities that form an integral part of the proposed development;
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• Indirect/secondary effects that arise from activities not explicitly forming part of the proposed development; and • Cumulative effects that arise from the combination of different impacts at a specific location, the recurrence of impacts of the same type at different locations, the interaction of different impacts over time, or the interaction of impacts arising from the scheme in conjunction with other development projects.
There is no statutory definition of what constitutes a significant effect. A significant effect may be broadly defined as an effect which, either in isolation or combination with others, should be taken into account in the decision-making process. This general definition will be used as the basis against which the significance criteria for environmental disciplines will be developed. The threshold of significance for predicted effects tends to vary between the environmental topics. A consistent approach is applied where suitable to prevent undue weight being given to a particular discipline to the detriment of another.
5.5. Cumulative Effects Consideration and assessment of cumulative effects with other grid routes (if considered applicable) and cumulative wind farm sites within the vicinity of the proposed Alwen Forest grid connection will be undertaken as part of the EIA. Each discipline will note the scope of the cumulative assessment if applicable.
5.6. Mitigation and Monitoring of Environmental Effects The ES will include a description of the measures envisaged to prevent, reduce and where possible remedy any significant adverse effects. Mitigation can be in the form of embedded mitigation, i.e. those measures incorporated in the design as environmental assessments were developed, or impact mitigation i.e. for impacts that are unavoidable through design, applying best practice and guidance recognised within the industry to attain environmentally acceptable levels, or those which are deemed acceptable through determination.
In line with the EIA Regulations, when identifying mitigation measures, the proposed development will take into account the practicability and cost effectiveness of the proposals and their efficiency in reducing environmental impacts. Where the effects of the impact are significant, and where there is uncertainty in the mitigation proposed, monitoring may be proposed to ensure that the mitigation is both required and effective. Monitoring will allow for adaptation of the mitigation measures to ensure that they are fit for purpose. Monitoring will be proportionate to the level of significance experienced and not simply proposed as monitoring for monitoring sake.
Once the final design has been adopted and account has been taken of any mitigation measures, residual effects will be identified. The significance of a residual effect will be determined by correlating the magnitude of the change arising from the scheme with the sensitivity of the particular attribute under consideration. The magnitude of change will be evaluated in accordance with Table 5.1, unless noted otherwise in each separate discipline.
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Table 5.1: Magnitude of Change
Magnitude Description
High Total loss or major alteration to key elements/features of the baseline conditions
Medium Partial loss or alteration to one or more key elements/features of the baseline conditions
Low Minor shift away from the baseline conditions
Negligible Very slight change from baseline conditions
Source: Natural Power
Where applicable in carrying out individual assessments, a scale of increasing sensitivity of the resource or receptor will be defined. This may be defined in terms of quality, value, rarity or importance and can be classed as ‘Low’, ‘Medium’ or ‘High’. For certain assessment areas, guidance will be taken from the value attributed to elements through designation or protection under law. Where assessment of this nature takes place the correlation of magnitude against sensitivity will determine a qualitative expression for the significance of the residual adverse effect. This is demonstrated in the matrix below, Table 5.2:
Table 5.2: Significance of Effect
Magnitude of Change High Medium Low Negligible
High Major Major/Moderate Moderate Moderate/Minor Medium Major/Moderate Moderate Moderate/Minor Minor
Low Moderate Moderate/Minor Minor Minor/Negligible Sensitivity
Source: Natural Power
Those residual adverse effects indicated as Major and Major/Moderate will be regarded as being significant effects in terms of the relevant legislation. However, other factors may have to be considered including the duration and the reversibility of the effect. We intend to focus the EIA on the significant effects and therefore propose to scope out the non-significant effects.
Question 3: Do consultees have any comments in relation to the approach to the Environmental Impact Assessment and to mitigation and monitoring?
6. Legal and Policy Context
This section summarises the main planning legislation relevant to the proposed grid connection. Each of the separate disciplines have outlined the legislative context in each of their sections and will be detailed further in the ES chapters.
The application will conform to the statutory requirements legislated by the Environmental Impact Assessment (Wales) Regulations 2017.
A Planning Statement will accompany the application for consent and assess the proposed development in a legal and policy context against the relevant legislation and planning policies in force. The Planning Statement will assess such documents at international, national, regional and local levels, where applicable, including but not limited to: • Planning Policy Wales Edition 10 (December 2018);
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• Technical Advice Note 8 (2005) Welsh Government; • Draft National Development Framework for Wales (currently out for consultation August 2019); • Conwy County Borough Council Local Development Plan (2013); • Conwy County Borough Council Supplementary Planning Guidance LDP 17: Onshore Wind Turbine Development (January 2015); • Denbighshire County Council Local Development Plan (June 2013); • Denbighshire County Council Renewable Energy Supplementary Planning Guide (April 2016); and • Conwy and Denbighshire Landscape Sensitivity and Capacity Assessment for Wind Energy Development (May 2013).
Any other emerging Supplementary Planning Guidance will also be accounted for in the submitted ES with the appropriate weighting given relative to established policies.
It is recognised that this renewable energy development, which is being facilitated by this grid connection, would contribute to the goals of the Well-being of Future Generations (Wales) Act 2015 and meet the principles of the Sustainable Management of Natural Resources (SMNR) as required by the Environment (Wales) Act 2016. The project would focus on these and references will be provided on how the project helps meet the goals and principles set out in these Acts.
7. Environmental Statement
The EIA process will result in the production of an ES. The ES will identify those features/receptors that have been agreed are likely to have a significant effect from the proposed development (or cumulatively with other projects) and will have an influence on the decision process.
The ES will focus on each of the broad topics identified within this scoping report, plus any others that develop throughout the remainder of the EIA process until submission.
Where features are considered, the assessment methodology, results, effects and mitigation proposed (if any) will be included. This will allow for the residual effect from the proposed development to be identified to allow the competent authority sufficient information to determine the application.
Although this scoping report is specifically relating to the grid connection for Alwen Forest Wind Farm, the ES will be assessing both the wind farm and grid connection in one document.
The ES will supplement the application and will also be accompanied by a Non-Technical Summary (NTS) a Pre-Application Consultation (PAC) Report, and a Planning, Design and Access Statement.
The ES is likely to follow the structure in Table 7.1.
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Table 7.1: Proposed ES structure
Chapter Title Author Introductory 1 Introduction Natural Power 2 Legal and Policy Context Natural Power 3 Approach to EIA Natural Power 4 Site Selection and Design Evolution Natural Power 5 Project Description Natural Power Biological 6 Ecology Assessment BSG Ecology Environment 7 Ornithology Assessment BSG Ecology Physical 8 Landscape and Visual Impact Assessment (LVIA) Land Use Environment Consultants 9 Cultural Heritage Assessment Headland Archaeology 10 Hydrology, Geology, Hydrogeological Natural Power Assessment 11 Traffic and Transport Assessment Natural Power 12 Noise Assessment TNEI Group 13 Forestry Assessment Tilhill Forestry 14 Health and Public Safety Natural Power 15 Aviation and Existing Infrastructure Coleman Aviation 16 Socio-Economic Assessment Natural Power Conclusion 17 Residual Effects, Synergistic Effects & Mitigation Natural Power
Source: Natural Power Question 4: Do consultees have any comments in relation to the proposed chapters to be included in the ES?
The ES will be produced both in a hard copy print and electronically. For the majority of consultees, unless otherwise requested, the ES will be provided electronically. Upon submission of the application, these documents will be made available for public inspection at appropriate locations to be agreed with the determining body and local planning authorities and will be distributed to the relevant consultees. A bilingual Non-Technical Summary will be submitted alongside the ES, which will provide a summary of the main findings and will be written in non-technical language to help enable a better understanding and overview of the assessments for the general public.
8. Embedded Mitigation and Further Layout Iterations
The design of the proposed Alwen Forest Wind Farm grid connection to date has been an iterative process, and the identified corridors have avoided known environmental and physical constraints as far as possible (embedded mitigation).
Throughout the remainder of the EIA process (until the submission of the ES), the grid connection corridors presented in this scoping report may be developed further (especially in light of the scoping opinion and public consultations).
Should any design changes occur that are likely to have a significant effect on the receptors identified these will be included within the EIA. If the changes are not likely to have a significant effect, these will
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first be discussed with the relevant consultees, to ensure that they too are in agreement with the applicants’ understanding before excluding them from the ES.
In the following sections the subject areas to be covered in the scoping report and ES are discussed. Where it is considered that certain subjects or particular aspects within subjects can be scoped out of the ES, evidence and a rationale is provided.
9. Ecology
9.1. Introduction This section sets out the proposed approach to assessing the potential ecological effects of the Alwen Forest Wind Farm Grid Connection.
Use of Existing Information to Inform the Interpretation of Impacts Detailed existing baseline ecological information of direct relevance to the potential grid connection corridors is limited to ongoing contextual survey in relation to the proposed Alwen Forest Wind Farm development to the west, and the operational Clocaenog Forest Wind Farm to the east.
Additional contextual ecological information is available for other wind farm developments in the wider area such as the consented Pant y Maen, and the operational Tir Mostyn and Brenig wind farms.
Embedded Mitigation and Layout Iterations As discussed in Section 4.2 the iterative design process has resulted in the omission of route options that would cross the Mynydd Hiraethog SSSI to the north of Llyn Brenig. This will substantively reduce the potential ecological impacts of the proposed grid connection.
9.2. Methodology
Legislation, Guidance and Assessment Methods The approach to the collection of baseline ecological data will be based on industry standard guidance wherever this is available and applicable to the site. For example, the Phase 1 habitat survey has been undertaken in accordance with Joint Nature Conservation Committee (JNCC) (2010) guidelines2.
Particular consideration has been given to habitats and species listed under Annexes 1 and 2 of the Habitats Directive (92/43/EEC), Schedules 5, 8 and 9 of the Wildlife and Countryside Act 1981 (as amended), and Section 7 of the Environment Wales Act (2016) in deriving the proposed approach to further work.
The ecological impact assessment will be based on Chartered Institute for Ecology and Environmental Management (CIEEM) guidance3. The process of assessment will involve: • Identifying the ecological features that will be subject to detailed assessment. Consideration will be given to the results of desk study and survey work, the conservation priority and legislative protection afforded to species and habitats present and empirical data from relevant research and monitoring work in determining these features. • Identifying and characterising construction and operational phase impacts and their potential effects
2 JNCC. (2010). Handbook for Phase 1 habitat survey - a technique for environmental audit. JNCC, Peterborough 3 CIEEM. (2019). Guidelines for ecological impact assessment in the UK and Ireland: terrestrial, freshwater and coastal. Version 1.1. Chartered Institute of Ecology and Environmental Management, Winchester
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• Determining the significance of these effects based on consideration of factors such as the likelihood of changes to: ecological processes and characteristics; the nature, extent structure and function of habitats; population size and viability of species; and the known resilience of features to change. • Incorporating measures to avoid and mitigate negative impacts and thus effects • Assessing the significance of any residual effects after mitigation. • Identifying appropriate compensation measures to offset significant residual effects • Identifying opportunities for ecological enhancement.
In accordance with CIEEM guidance, conclusions with regard to significance of effects will be placed in a geographical context (i.e. an effect could be significant on a scale between local and international),and will be precautionary in nature.
The ongoing approach to consultation, desk study and field survey that will inform the assessment is set out in the following sections.
Consultation A meeting was held with Natural Resources Wales (NRW) on 2 April 2019. This was attended by members of the NRW North Planning and Energy Delivery teams, and by Matthew Ellis, Senior Species Officer.
The principal aim of the meeting was to discuss and agree an approach to the ecological (and ornithological) survey work for the Alwen Forest Wind Farm in 2019. Grid connection options were also introduced, and the approach to data collection discussed in principle. At the time of the meeting, routes to the north and south of Llyn Brenig were under consideration, and preferred options had not been identified.
No specific ecological concerns were raised by NRW in the initial discussion of route options, albeit these were at a very early stage at that time and there was limited ecological data available in relation to them.
Other nature conservation stakeholders have not been formally consulted with regard to route options to date.
Desk-based Review Desk study has involved a review of open source aerial photography and Ordnance Survey mapping, the UK Government’s ‘Magic’ website4 and survey information relating to the Alwen Forest, Tir Mostyn and Clocaenog Forest Wind Farm developments.
Cofnod (North Wales Environmental Information Service) data supplied in relation to Alwen Forest Wind Farm has also been reviewed. A new data request will need to be submitted to ensure all relevant records have been considered. Data have also been requested from the Clocaenog Red Squirrels Trust to determine the proximity of recent squirrel records to the chosen grid connection route.
9.3. Survey Work
Habitat Survey A Phase 1 Habitat Survey of the site was completed by BSG Ecology (BSG) between 19 and 22 August 2019 in accordance with industry standard (JNCC, 2010) survey guidance. This involved mapping all broad habitat types along the two grid connection corridor options under consideration. The survey was extended to consider the potential of the habitats to support protected species.
The results are shown on Figure 9.1 ‘Survey Area Overview’ and Figures 9.2-9.7 ‘Phase 1 Habitat Survey Results’ .
4 Available online from: https://magic.defra.gov.uk/ (last accessed 15/10/2019)
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Protected Species Survey The following additional survey work is proposed to inform the application: • Otter Lutra lutra, and water vole Arvicola amphibious survey of watercourses within 200 m of the route of the grid connection corridor options (this is consistent with the agreed distances either side of tracks for Alwen Forest Wind Farm). Survey methods will be based on those recommended in Chanin (2003)5, and Dean et al (2016)6. • A survey to determine the quality of habitat on and either side of the proposed grid connection routes to support red squirrel. The extent of the area surveyed will depend on the level of forest clearance required. If a wide easement is required for an overhead line option, all areas of woodland isolated from Clocaenog Forest will be assessed in terms of their potential to support red squirrel; this will take the form of a habitat suitability survey followed by presence absence survey work. In the event that an underground cable is favoured, it is proposed to survey the forest 100 m either side of the grid corridor.
These surveys are required to inform an approach that avoids contravention of UK wildlife legislation.
9.4. Results
Desk-based Review: Designated Sites There is one SSSI within 2 km of the grid corridor; Mynydd Hiraethog. The SSSI lies directly north of the northern of the two corridor options under consideration and east of Llyn Brenig. A small ‘tongue’ of dry heath that forms part of the SSSI extends into the northern corridor within the plantation forestry at Isgaer- wen. There is therefore some potential for the grid connection to go through/over this area. It was notified for its botanical and ornithological interest. It represents one of the four remaining extensive tracts of sub- montane heather (Calluna vulgaris) heath in the former county of Clwyd and has been traditionally managed as a grouse moor. The drier heath vegetation grades into wetter acidic blanket bog vegetation where the peat is deeper. The SSSI also supports extensive areas of soligenous mires, and natural oligotrophic lakes.
Data will need to be secured from Cofnod to confirm that there are no (non-statutory) wildlife sites to the east of Llyn Brenig that might be affected by the proposed route. Wildlife sites to the south of Llyn Brenig are outside the footprint of the development. The closest is Afonydd Brenig and Alwen Wildlife Site a stream directly south of Pont y Rhuddfa. The interest is listed as running water.
Desk-based Review: Species Data Baseline survey and desk study in relation to the proposed Alwen Forest Wind Farm development and the Clocaenog Forest Wind Farm has established: • Bats. The most extensive work undertaken locally is ongoing survey at Alwen Forest. This has identified a minimum of eight species which use that site. Common pipistrelle Pipistrellus pipistrellus, soprano pipistrelle Pipistrellus pygmaeus, a long-eared bat species (presumably Plecotus auritus), one or more Myotis species and noctule Nyctalus noctula occur commonly. Leisler’s bat Nyctalus leisleri, lesser horseshoe bat Rhinolophus hipposideros and Nathusius’ pipistrelle Pipistrellus nathusii have been recorded on an infrequent or very occasional basis. A review of data from the Clocaenog, Brenig and Pant y Maen wind farm planning applications suggests this bat assemblage is likely to be typical of the wider landscape.
5 Chanin, P. (2003). Monitoring the Otter Lutra lutra. Conserving Natura 2000 Rivers Monitoring Series No. 10, English Nature, Peterborough.
6 Dean, M., Strachan, R., Gow, D. & Andrews, R. (2016). The water vole mitigation handbook. The Mammal Society, London.
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• Dormouse survey at the proposed Alwen Forest Wind Farm development in 2018 and 2019 has not recorded the species within the plantation woodland to date. Survey work in relation to dormouse at Clocaenog Forest Wind Farm was conducted between 2009 and 2011, and again between 2016 and 2019 inclusive, with further work scheduled for future years as part of ongoing operational phase monitoring (SLR, 20187). This has involved the installation of dormouse boxes throughout the plantation. Dormice have been found in various areas of Clocaenog Forest; of particular relevance is that animals have been recorded in scrub along the edge of the forest adjacent to the Tir Mostyn Wind Farm, which is within the ‘dense scrub’ shown on Figure 9.5 on the eastern edge of the minor road. • Otter has been recorded from Llyn Brenig and Alwen Reservoir, by NRW staff within Clocaenog Forest and at various other locations within 2 km of the grid connection routes. • Red squirrel Sciurus vulgaris.is present in both Alwen and Clocaenog Forests, where ongoing monitoring has shown there to be a widespread but sparse population. • Work completed by SKM Enviros8 to assess the quality of the habitat resource within Clocaenog Forest for squirrels identified that the forest along much of the two route options was of low value to the species other than a small area of high value woodland on the southern of the two grid corridor options. Further liaison is needed with the Clocaenog Red Squirrels Trust to obtain recent sightings and population data and contemporary information on habitat usage • Water vole has been noted from a number of small watercourses within Clocaenog Forest and at Pant y Maen. • Reptiles occur in local areas of forest. Records primarily relate to adder (Vipera berus) and common lizard (Zootoca vivipara).
Habitat Survey The Phase 1 habitat survey confirmed the predominant habitat type along both route corridor options to be coniferous plantation. This is typically formed of dense, mixed-age plantings of Sitka spruce (Picea sitchensis). The plantation is managed in rotation, and all growth stages are represented, from recently felled or replanted areas to stands of intermediate age and mature trees. Younger plantation coupes support regenerating dry heath and/or acid grassland beneath the conifers and areas which have been left to naturally regenerate are similar but include developing semi-natural broadleaved woodland.
A mosaic of dry heath and acid grassland, tall ruderals and scattered scrub is present alongside the tracks, with occasional dry ditches and areas of species-poor neutral grassland. Wide strips of bare ground are present alongside forestry tracks where these have been widened during the construction of the Clocaenog Forest Wind Farm. Between the southern substation in Alwen Forest and the western part of Clocaenog Forest at Pont y Rhuddfa and Swch Gaer Wen, and at various other locations along the route options, the forest gives way to species-poor semi-improved acid grassland and rank marshy grassland dominated by soft rush Juncus effusus. Several small belts of mixed and deciduous woodland are present between Alwen and Clocaenog forests.
Small areas of wet heath and swamp are associated with Clywedog Reservoir, which lies to the east of the grid corridor route through Clocaenog Forest Wind Farm. This habitat is unlikely to be impacted by the grid connection works.
No non-native invasive species were recorded.
7 SLR (2018). Clocaenog Forest wind farm: dormouse monitoring 2018. Report to Innogy Renewables, Baglan. 8 SKM Enviros. (2009). Red squirrel habitat suitability mapping report. Report to nPower Renewables, Baglan.
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Protected Species Survey An otter spraint was recorded at Clywedog Reservoir. No other signs of protected species were noted during the Phase 1 survey.
Species-specific work has not been completed to date.
9.5. Discussion The ecological impact assessment (EcIA) will assess the likely effects of construction, operation and decommissioning of the proposed Alwen Forest Wind Farm grid connection on ecological receptors.
In BSG’s professional opinion, it is unlikely that there will be significant effects on the ecological interest of statutory designated sites (alone or cumulatively) as a result of the proposed grid connection. There may be a need to pass over or under a small area of SSSI that extends into the plantation at Isgair-wen, but it should be possible to avoid impacts on the dry heath habitats in this location.
Other than this discrete area there is a lack of a clear effect pathway with regard to the habitats/species for which the SSSI was notified. Impacts on non-statutory sites could arise through sediment mobilisation; this will need to be considered and appropriate mitigation detailed in the EcIA.
Corridor 2 does not follow an existing track for approximately 800 m through the afforested habitat, but the remainder of Corridor 2 and Corridor 1 will follow existing forest tracks wherever possible. The degree of additional felling on either side of the routes is yet to be determined and will be dependent on whether the cables will be overhead or underground, and (if the former) the required width of the easement.
The key considerations within the ecological assessment are likely to be habitat loss and the creation of a barrier to movement to red squirrel and hazel dormouse during the construction and operational life of the grid connection, and potential disturbance impacts to these species and to otter during construction. The likely scale of impact on these species will be informed by site survey and existing data.
It is likely that effects on water vole, if present, can be readily mitigated, and that it will be possible to avoid the loss of broad-leaved semi natural woodland (thereby minimising potential for impacts on roosting bats) through detailed route design. Mitigation measures will also need to be included to ensure legislative compliance with regard to reptiles and badger. As any potential impacts on fish and invertebrates should be possible to readily mitigate, the professional opinion of BSG is that these impacts can be scoped out of the detailed assessment.
Table 9.1: Summary of EcIA considerations
Receptor Detailed Assessment Required? (Y/N) – Statutory Protected Sites N – Non-statutory Protected Sites Y – Red squirrel Y – Hazel dormouse Y – Bats N – Otter Y – Pine marten N – Reptiles Compliance only – Badger Compliance only – Water vole Compliance only – Fish N
Source: BSG Ecology
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9.6. Conclusions Habitats along the majority of the grid connection corridor options are of limited ecological value, with the dry heath and heath and acid grassland mosaic likely to rapidly recolonise any extended easement areas within the plantation, leading to local conservation gain.
The potential for significant ecological effects on protected species is likely to be limited to red squirrel, dormouse and otter. The former two species could be affected by habitat loss and fragmentation throughout the operational life of the grid connection. Otter could potentially be affected during construction as a result of disturbance. Desk study data suggests all three species have occurred along the connection routes in the past.
The potential for these species to be affected will depend on whether they are currently present in the plantation, and whether an OHL or underground grid connection option is taken forward. An OHL, with an associated easement, is likely to impact more on protected species, due to increased habitat fragmentation.
Survey work will be undertaken to determine the current habitat suitability and likely presence/absence of these species along the route options. This will be completed in accordance with industry standard guidance, and the results used to inform the assessment of impacts and any associated mitigation requirements.
Question 5: Do consultees consider the scope of works for ecological assessment appropriate?
Question 6: Do consultees agree on the receptors to be scoped out?
10. Ornithology
10.1. Introduction This section sets out the proposed approach to assessing the potential ornithological effects of the Alwen Forest Wind Farm Grid Connection.
Use of Existing Information to Inform the Interpretation of Impacts Detailed existing baseline ornithological information of direct relevance to the potential grid connection route corridors is limited to ongoing contextual survey in relation to the proposed Alwen Forest Wind Farm development to the west, and the operational Clocaenog Forest Wind Farm to the east.
Additional contextual ornithological information is available for other wind farm developments in the wider area such as the consented Pant y Maen, and the operational Tir Mostyn and Brenig Wind Farms.
Embedded Mitigation and Layout Iterations As discussed in Section 4.2, the iterative design process has resulted in the omission of route options that would cross the Mynydd Hiraethog SSSI to the north of Llyn Brenig. This will reduce the potential for impacts on lekking black grouse Lyrurus tetrix; leks are present in areas of the SSSI to the north and east of Llyn Brenig.
10.2. Methodology
Legislation, Guidance and Assessment Methods Particular consideration has been given to bird species listed under Annex 1 of the Birds Directive (2009/147/EC), Schedule 1 of the Wildlife and Countryside Act 1981 (as amended), and Section 7 of the Environment Wales Act (2016) in deriving the proposed approach to survey and assessment.
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The ornithological impact assessment will be based on Chartered Institute for Ecology and Environmental Management (CIEEM) guidance9. The process of assessment will involve: • Identifying the ornithological features that will be subject to detailed assessment. Consideration will be given to the results of desk study and survey work, the conservation priority and legislative protection afforded to species and habitats present and empirical data from relevant research and monitoring work in determining these features. • Identifying and characterising construction and operational phase impacts and their potential effects • Determining the significance of these effects based on consideration of factors such as the likelihood of changes to: ecological processes and characteristics; the nature, extent structure and function of habitats; population size and viability of species; and the known resilience of features to change. • Incorporating measures to avoid and mitigate negative impacts and thus effects • Assessing the significance of any residual effects after mitigation. • Identifying appropriate compensation measures to offset significant residual effects • Identifying opportunities for ecological enhancement (with an emphasis on birds).
In accordance with CIEEM guidance, conclusions with regard to significance of effects will be placed in a geographical context (i.e. an effect could be significant on a scale between local and international), and will be precautionary in nature.
The ongoing approach to consultation, desk study and field survey that will inform the assessment is set out in the following sections.
Consultation
A meeting was held with NRW on 2 April 2019. This was attended by members of the NRW North Planning and Energy Delivery teams, and by Patrick Lindley, Senior Ornithologist.
The principal aim of the meeting was to discuss and agree an approach to the ornithological (and ecological) survey work for the Alwen Forest Wind Farm in 2019. Grid connection options were also introduced, and ornithological data relating to them presented (this was issued in report form following the meeting). At the time of the meeting, routes to the north and south of Llyn Brenig were under consideration, and preferred options had not been identified.
Other nature conservation stakeholders have not been formally consulted with regard to route options to date.
Desk-based Review Desk study has involved a review of open source aerial photography and Ordnance Survey mapping, the UK Government’s ‘Magic’ website and survey information relating to the Alwen Forest and Clocaenog Forest wind farm developments. This has included RSPB Cymru and Cofnod (North Wales Environmental Information Service) data for the plantations and surrounding habitats.
Wetland Bird Survey (WeBS) data for Llyn Brenig, Llyn Bran and Alwen Reservoir have been supplied by the British Trust for Ornithology, and data held by Cofnod for these waterbodies have been reviewed.
9 CIEEM. (2019). Guidelines for ecological impact assessment in the UK and Ireland: terrestrial, freshwater and coastal. Version 1.1. Chartered Institute of Ecology and Environmental Management, Winchester
Alwen Forest Wind Farm Grid Connection 23
10.3. Survey Work
Ornithological Survey A Phase 1 Habitat Survey of the site was completed in August 2019 in accordance with industry standard (JNCC, 2010)10 survey guidance. This involved mapping all broad habitat types along Corridors 1 and 2 The survey was extended to consider the potential of the habitats to support protected species (including birds).
Field survey Vantage point (VP) surveys were conducted on a twice monthly basis during the period mid-December 2018 to March 2019 (inclusive). The purpose of this work was to characterise the wintering waterbird community of the reservoirs11, to collect data on flight activity and to determine any regularly used flight lines (between the reservoirs or across the wider landscape).
Two VP locations were selected to obtain maximum visual coverage of the areas adjacent to the northern and southern shores of Llyn Brenig. The VP viewsheds were scanned constantly until a target species was detected. The flight line and height of the bird was then recorded until it landed or was lost from view. In addition to the VP data, counts of waterfowl on Llyn Brenig and Llyn Bran were completed (counts of waterfowl on Alwen Reservoir have been conducted as part of winter survey work in relation to the wind farm).
The results were presented in a short report that was issued to NRW following a meeting held on 2 April 2019.
It is anticipated that additional survey for raptors may be required during 2020. The spatial coverage and need of this work will depend on the width of the easement required (i.e. if the grid connection is underground and the extent of the easement very limited this work may not be necessary).
Long term data sets have been collected for nightjar (2014-2019 inclusive) and black grouse (2008-09 and 2014-201912 inclusive) in relation to the planning application, construction and operational phases of the Clocaenog Forest Wind Farm. These cover the entirety of afforested habitats along Corridors 1 and 2 (they exclude small areas of woodland and scrub directly south of Llyn Brenig) and are considered sufficient to provide a robust baseline to inform the impact assessment for the grid connection.
The merits of continuing data collection on bird flight lines in relation to the grid connection options was discussed at the meeting with NRW in April 2019. Following issue of a report (BSG Ecology, 2019)13 capturing the data in tables and on figures, Tomos Hughes (Senior Development Planning Advisor) wrote14 on 15 May 2019,
“I would also like to confirm that we have reviewed the additional document presented at the meeting regarding the potential grid connection routes (Alwen Forest Grid Connection, Draft Ornithology Report March 2019). NRW agree that in light of the results to date, there is no need to continue surveying of these routes.”
10 JNCC. (2010). Handbook for Phase 1 habitat survey - a technique for environmental audit. JNCC, Peterborough 11 Llyn Brenig, Alwen Reservoir and Llyn Bran (a smaller reservoir to the north of Llyn Brenig). Counts were conducted at the former and the latter, with Llyn Alwen regularly surveyed as part of work related to the proposed wind farm (as opposed to the grid connection). Flight line work focussed on Llyn Brenig. 12 For both nightjar and black grouse the most recent data currently available are for 2018. 13 BSG Ecology. (2019). Alwen Forest grid connection ornithology report March 2019. Report to Innogy UK, Baglan.
14 Email from Tomos Hughes to Owain Gabb. NRW reference CAS-83587-P7W3
Alwen Forest Wind Farm Grid Connection 24
10.4. Results
Desk-based Review: Designated Sites There is one SSSI within 2 km of the site boundary; Mynydd Hiraethog. The SSSI lies directly north of the northern Corridor 1. It was notified for its botanical and ornithological interest.
The SSSI citation states that it supports a diverse community of upland breeding bird species, including hen harrier Circus cyaneus, merlin Falco columbarius, golden plover Pluvialis apricaria, dunlin Calidris alpina, lapwing Vanellus vanellus, curlew and short-eared owl Asio flammeus. The SSSI citation does not refer to wintering bird interest.
Data will need to be secured from Cofnod to confirm that there are no (non-statutory) wildlife sites to the east of Llyn Brenig that might be affected by the proposed grid connection. Wildlife sites to the south of Llyn Brenig are outside the footprint of the development with the closest Afonydd Brenig and Alwen Wildlife Site; a stream directly adjacent to the plantation edge at Pont y Rhuddfa. No ornithological interest is cited.
Desk-based Review: Species Data Baseline survey and desk study has established: • WeBS coverage of reservoirs in the area is limited. They are considered of ‘low priority’ by the British Trust for Ornithology (BTO), indicating they are known to support a limited waterfowl community. The data available indicate they are used by low numbers of common waterfowl. • Osprey Pandion haliaetus breeds on an artificial platform on Llyn Brenig. The reservoir is stocked with fish, and the birds are likely to provision their young from it. A VP overlooking Llyn Alwen (regularly visited as part of wind farm related survey) has not recorded regularly osprey activity. • Goshawk Accipiter gentilis and crossbill Loxia curvirostra breed in suitable mature forest coupes throughout the area. • Hen harrier and merlin breed on Mynydd Hiraethog, with territory locations relatively remote from the potential grid connection routes (west of Alwen Forest). Short-eared owl has historically bred in the area; no records of recent breeding have been obtained. • Kestrel Falco tinnunculus and barn owl Tyto alba are present and will breed in suitable buildings and trees locally. The former has been regularly recorded during survey work in relation to the proposed Alwen Forest Wind Farm development, • Red kite Milvus milvus and hobby Falco subbuteo have been noted over moorland and farmland in the area. VP survey indicates that neither occurs with regularity over coniferous plantation. • Nightjar Caprimulgus europaeus occurs in suitable areas of clearfell in plantation throughout the area. Monitoring work completed in relation to the Clocaenog Forest Wind Farm (SLR, 2018a15) has established that there are ‘clusters’ of territories and nests in suitable habitat within the forest. The closest of these to the potential grid connection corridor were around Rhyd Galed and to the north of Clywedog Reservoir. • Black grouse Lyrurus tetrix has been recorded lekking in moorland to the north and east of Llyn Brenig, and to the west and north of Alwen Forest. Monitoring work completed in relation to the Clocaenog Forest Wind Farm (SLR, 2018b)16 has established that the nearest leks are on Marial Gwyn, to the north of the plantation at Isgaer Wen/to the west of the Tir Mostyn Wind Farm. Small leks are typical of the area and use of woodland in the area by grouse would be expected.
15 SLR (2018a). Clocaenog Forest Wind Farm: nightjar population and productivity monitoring report 2018. Report to Innogy Renewables, Baglan 16 SLR. (2018b). Clocaenog Forest Wind Farm: black grouse monitoring report 2018. Report to Innogy Renewables, Baglan.
Alwen Forest Wind Farm Grid Connection 25
• Breeding waders typically occur on areas of moorland and farmland relatively remote from plantation edges. Small numbers of curlew Numenis arquata, snipe Gallinago gallinago and oystercatcher Haematopus ostralegus have been recorded in the general area.
Bird Survey The results of VP surveys were as follows: • VP survey around Llyn Brenig in winter 2018/19 recorded 70 waterfowl flights (excluding gulls). These involved seven species; greylag goose Anser anser, Canada goose Branta canadensis, mallard Anas platyrhynchos, goldeneye Bucephala clangula, goosander Mergus merganser, grey heron Ardea cinerea and cormorant Phalacrocorax carbo. The species composition reflected the limited desk study data available. • None of the flights crossed either of the potential connection routes at a height that could have resulted in collision for OHL. Waterfowl were recorded commuting into/out of the northern part of the reservoir over a shallow valley; few flights were noted heading south of the Llyn Brenig dam. • Herring gull Larus argentatus, lesser black-backed gull Larus fuscus and great black-backed gull Larus marinus were recorded on the majority of watches, and gull flight lines were noted in two broad corridors; one over the dam to and from the south, and the other over the pasture north-east of Llyn Brenig, to and from the reservoir. During dusk watches, greater numbers of birds were observed flying onto the reservoir along these corridors, to roost. These flights were generally within the height band 30-100 m when over adjacent moorland/surrounding habitats (far higher altitude than the potential OHL).
Waterbody counts recorded: • A total of eleven waterfowl species; greylag goose, Canada goose, mallard, tufted duck, (a vagrant) ring-necked duck Aythya collaris, goldeneye, goosander, great-crested grebe, cormorant, grey heron and coot. The species composition was very similar for Llyn Brenig and Llyn Bran, albeit there was no clear flight line recorded between them. Mallard, greylag goose, cormorant and grey heron were recorded infrequently and in low numbers, on and in flight over Llyn Alwen during winter 2018/19.
10.5. Discussion The ornithological impact assessment (OIA) will assess the likely effects of construction, operation and decommissioning of the proposed Alwen Forest Wind Farm grid connection on ornithological receptors.
In BSG’s professional opinion, it unlikely that there will be significant effects on the ornithological interest of designated sites (alone or cumulatively) as a result of the proposed grid connection. The timing of the works should take account of impacts on lekking black grouse, with other controls identified in a CEMP as necessary. Otherwise the species for which the SSSI was notified are not known to breed close to grid route corridors, and impacts on populations through collision and displacement are very unlikely.
Corridor 2 does not follow an existing track for approximately 800 m through the afforested habitat, but the remainder of this route and Corridor 1 will follow existing forest tracks wherever possible. The degree of additional felling on either side of the routes is yet to be determined and will be dependent on whether the cables will be installed overhead or underground, and (if the former) the required width of the easement.
The key considerations within the ornithological assessment are likely to be habitat loss and disturbance to forest nesting species such as goshawk, crossbill and nightjar. Potential changes in the quality of the resource within the plantation to black grouse will also need to be considered. Significant effects on waterfowl using Llyn Brenig appear very unlikely to occur, as the number and diversity of birds using the reservoir is very low, and their flight lines do not indicate potential for collision.
Alwen Forest Wind Farm Grid Connection 26
Table 10.1: Summary of OIA considerations
Receptor Detailed Assessment Required? (Y/N) – Protected Sites – N – Waterfowl (including gulls) – N – Waders – N – Goshawk / forest nesting raptors – Y – Other raptors – N – Crossbill – Y – Nightjar – Y – Black Grouse – Y
Source: BSG
10.6. Conclusions The proposed grid connection may result in habitat loss and disturbance to specially protected bird species, particularly goshawk and crossbill, as well as to birds of conservation concern such as black grouse and nightjar. The level of impact will depend on the proximity of suitable habitat to the chosen grid connection route, the results of survey, and whether an overhead line or a cable is the preferred solution. Appropriate mitigation will need to be identified for these species, albeit the easement may present good quality foraging habitat for grouse and nightjar as it revegetates.
Notwithstanding the above, it is anticipated that ornithological issues with regard to the proposals are of relatively low magnitude.
Question 7: Do consultees consider the scope of works for ornithology assessment appropriate?
Question 8: Do consultees agree on the receptors to be scoped out?
11. Landscape and Visual
11.1. Introduction This section sets out the proposed approach to assessing the potential effects on landscape character and public visual amenity of the proposed Alwen Forest Wind Farm grid connection. The primary guidance for Landscape and Visual Impact Assessment (LVIA) is the Guidance for Landscape and Visual Impact Assessment, 3rd Edition (GLVIA3)17. In addition, Scottish Natural Heritage (SNH) has published a number of documents that have been adopted as industry standard good practice on landscape and visual assessments of wind farm proposals and supporting infrastructure. One overarching LVIA will be produced for the proposed Alwen Forest Wind Farm and grid connection and will be completed by Chartered Landscape Architects, in accordance with relevant best practice documents.
In accordance with GLVIA3, landscape and visual effects will be considered separately. The landscape assessment will consider the effects of the proposed Alwen Forest Wind Farm grid connection on the existing landscape character, pattern of land, and the rural and urban elements within the Study Area. The visual assessment will consider the impact of the development on public visual amenity experienced by people within the Study Area, including people in nearby settlements, using roads and paths, and visiting public places of interest. The LVIA will focus on landscape and visual receptors that may experience potentially significant effects. The LVIA will take into account the proposed micrositing distance which is
17 Landscape Institute and the Institute of Environmental Assessment (2013) Guidelines for Landscape and Visual Impact Assessment. 3rd Edition
Alwen Forest Wind Farm Grid Connection 27
expected to be 50 m for wind turbines and associated infrastructure, and around 20 m to microsite the wooden poles associated with the grid connection, if OHL option is pursued.
An indicative Zone of Theoretical Visibility (ZTV) map has been generated for the grid connection route corridors considered for the Scoping Report; this is shown on Figure 11.1. The ZTV map has considered the theoretical visibility of the grid connection as an OHL as this would be the “worst case” scenario from a visual perspective. It has been modelled on 'bare earth' digital terrain and does not take into consideration the screening provided by existing vegetation, as the Study Area contains forestry activities resulting in a working landscape that is dynamic and undergoing constant change. The level of screening will vary as trees are felled and new ones grow. An additional ZTV is provided in Figure 11.2 which compares the theoretical visibility of the grid connection route corridors with the theoretical visibility of the proposed wind turbines of the Alwen Forest Wind Farm.
It is proposed that the Study Area for the grid connection component of the LVIA will cover a radius of 4 km from the selected route of the OHL. This is considered to be a maximum distance, beyond which significant effects are unlikely to occur as OHL and associated poles become difficult to discern beyond 4 km. In the case that the grid connection is constructed as an underground cable, the Study Area will be reduced to a radius of 1 km from the cable route and will consider the potential landscape and visual impacts during the construction phase. This is entirely within the Alwen Forest Wind Farm LVIA Study Area.
Question 9: Do consultees consider the size of the 4 km radius Study Area for the grid connection (for OHL) to be appropriate?
11.2. Planning Policy The following national and regional policy documents and supplementary guidance will be considered in the assessment.
National Planning Policy Planning Policy Wales (2018)18 sets out the land use planning polices for the Welsh Government. It is supplemented by a series of Technical Advice Notes (TANs). National policy and guidance on onshore renewable energy technologies is set out in TAN 8: Planning for Renewable Energy (2005) National Policy Statement for Electricity Network Infrastructure ( EN-5)19 is a UK national planning policy documents relating to grid connections, although most relevant for larger scale electricity infrastructure than considered for the Alwen Forest Wind Farm grid connection.
Local Development Plan The grid connection route corridors are located within both the DCC and CCBC local authority areas. The Denbighshire LDP 2006-2021 (Adopted May 2013) and Conwy Local Development Plan (LDP) 2007-2022 (Adopted October 2013) are therefore the relevant land use planning documents for the area. The Conwy LDP is supported by Supplementary Planning Guidance (SPG) LDP11: Landscape Sensitivity and Capacity for Onshore Wind Turbine Development (November 2014) and SPG LDP24: Renewable Energy (February 2017). The Denbighshire LDP is also supported by an SPG on Renewable Energy (April 2016).
Question 10: Are consultees aware of any other supplementary guidance of relevance to landscape and visual issues in relation to grid connections that should be considered?
18 Available online from: https://gov.wales/sites/default/files/publications/2019-02/planning-policy-wales- edition-10.pdf (last accessed 26/09/2019) 19 Available online from: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/47858/1 942-national-policy-statement-electricity-networks.pdf (last accessed 14/10/2019)
Alwen Forest Wind Farm Grid Connection 28
11.3. Grid Connection Route Corridors The grid connection corridors are located on the eastern and southern sides of Llyn Brenig; a large man- made water body flanked by hills comprising moorland and forested areas. They are illustrated on Figure 11.1 and 11.2. Along its northern section, running north-south, the grid connection corridor largely follows an unnamed road (forming the western edge of the corridor) which runs through the working Clocaenog Forest at an elevation of between 400 m and 470 m Above Ordnance Datum (AOD). A number of forestry tracks cross the grid connection corridor to join the unnamed road along with the Clwydian Way Regional Trail. Along the western edge of the road and adjacent to the grid connection corridor is the operational Tir Mostyn Wind Farm in the north and Foel Goch Wind Fam to the south (which occupies a ridgeline at approximately 516 m AOD) (although the two sections of turbine placement are considered as one wind farm ‘Tir Mostyn and Foel Goch’ Wind Farm). The operational Clocaenog Forest Wind Farm encompassed the north-south alignment of the grid connection corridor, as well as the forested areas to the east and west of it.
There are two corridor options for the southern section of the grid connection, running east-west. Corridor 1 follows a forestry track through the Isgaer-wen plantation in the east at a maximum of 470 m AOD, from where it descends to the south-eastern corner of Llyn Brenig. The corridor includes the dam wall that contains the reservoir along its southern edge. The corridor crosses the northern extremity of the Afon Brenig (a tributary river of the River Alwen). The Afon Brenig valley to the south consists of rolling landform, woodland copse/tree groups and an intricate field pattern derived from stone wall boundaries, characteristic of the Denbigh Moors National Landscape Character Area (NLCA) and provides a strong rural character/setting to the corridor.
Corridor 2 follows an unnamed road at approximately 400 m AOD which runs mostly through forest and partly through an open area comprising a relatively steep south facing slope overlain with pastoral fields. Corridor 2 meets Corridor 1 at the Afon Brenig with both options then continuing to the west, crossing the B4501 and terminating at a proposed substation in the Alwen Forest Wind Farm site. Public rights of way cross both of the corridor options.
Felling requirements for either OHL or underground grid connections will be determined along with the finalised route design.
11.4. Methodology
Routeing Considerations The grid connection corridors have evolved following initial landscape and visual feasibility work. The ES will present the rationale behind the final grid connection route. While recognising that the final route will need to balance a wide range of technical, economical and environmental considerations, the objective is for it to accord with its setting in terms of landform and pattern, and to avoid visually intrusive breaching of skylines.
Landscape Character Landscape receptors to be considered will include: • Landscape elements and features along the finalised route; • Landscape character types and/or areas within the Study Area, as identified in published character assessments; • LANDMAP aspect areas along the finalised route; and • The special qualities of landscape-related planning designations at the national, regional and local level.
Predicted changes in both the physical landscape and landscape character will be identified. Effects will be considered in terms of the magnitude of change to the landscape, including its key characteristics as
Alwen Forest Wind Farm Grid Connection 29
set out in published landscape character assessments and LANDMAP data. The sensitivity of the landscape will also be taken into account, acknowledging its underlying susceptibility, and the value placed on the landscape by society, which may be indicated through designation or LANDMAP evaluation.
NRW’s National Landscape Character Areas (NLCAs) form the broadest scale of landscape character assessment in Wales. The Alwen Forest Wind Farm and grid connection corridors lie within the Denbigh Moors/Mynydd Hiraethog NLCA. Rhos Hills NLCA is situated in proximity to the northern tip of the grid connection corridor.
The 4 km radius Study Area includes parts of the unitary authorities of Denbighshire and Conwy. However it is acknowledged that at a regional scale, there are no current published landscape character assessments for Denbighshire and Conwy.
LANDMAP All five aspect areas (Geological Landscape, Landscape Habitats, Visual and Sensory, Historic Landscape and Cultural Landscape) will be considered in the LVIA, with reference to published LANDMAP data. LANDMAP aspect areas within the grid connection corridors are provided in Table 11.1.
Table 11.1: LANDMAP aspect areas within the grid connection corridors
Aspect Area Aspect ID Aspect Name Overall Evaluation
Geological Landscape DNBGHGL078 Clocaenog Forest Moderate
DNBGHGL090 Foel Goch Moderate
CNWGL098 Clocaenog Forest Moderate
CNWGL097 Mwdwl-eithin Moderate
Landscape Habitats DNBGHLH057 Clocaenog Conifer Forest High
DNBGHLH058 Llyn Brenig Upland Heath Outstanding
CNWLH077 Clocaenog Forest High
CNWLH079 Clocaenog grassland clearings Low
CNWLH083 Cerrigydrudion grasslands Moderate
CNWLH074 Alwen Forest Moderate
Visual and Sensory DNBGHVS068 Clocaenog Forest Low
CNWVS007 Clocaenog Forest west Low
CNWVS045 Alwen valley High
Historic Landscape DNBGHHL170 Unnamed High
CNWHL012 Clocaenog Forest High
CNWHL078 Alwen & Brenig High
CNWHL041 Bryn Gors-goch Moderate
Cultural Landscape DNBGHCL017 Clocaenog Forest High
CNWCL018 Conwy uplands High
DNBGHCL016 Denbigh Moors High
/Source: LANDMAP
The LANDMAP aspect areas through which the grid connection route passes will be a subset of those assessed in the wind farm LVIA. The additional effects of the grid connection will only be considered where the route crosses a LANDMAP aspect area. The assessment will focus on aspect areas of ‘outstanding’
Alwen Forest Wind Farm Grid Connection 30
or ‘high’ overall evaluation. Visual and Sensory aspect areas of ‘moderate’ overall evaluation will also be considered where scenic quality and/or character criteria are ‘outstanding’ or ‘high’. The LANDMAP assessment for the wind farm (including the grid connection) as a whole will be included as an appendix to the LVIA.
Question 11: Is the proposed approach and scope for the assessment of effects on landscape character and LANDMAP aspect areas considered to be appropriate?
Designated Landscapes The only designated landscape within the 4 km Study Area is the Hiraethog Special Landscape Area (SLA) situated to the west of the grid connection corridors and approximately 3 km distant at its nearest point. While it is recognised that this is a locally important landscape with visual, cultural, historical geological and ecological characteristics and qualities. it is considered unlikely in LUC’s professional opinion that the grid connection (whether OHL or underground) will have additional landscape and visual impacts to the wind farm that would affect these special qualities a significant degree, and therefore it is not proposed to consider the effects of the grid connection on this designation.
Question 12: Is the proposed approach and scope for the assessment of effects on designated landscapes considered to be appropriate?
Visual Receptors Visual receptors to be considered will include: • People within settlements; • People travelling on major roads; • People using walking routes and cycle routes; and • People visiting areas of interest such as visitor attractions, viewpoints and hill summits.
Visual effects may be experienced by people at different locations around the Study Area, at static locations (for example settlements or viewpoints) and transitional locations (such as sequential views from routes). Visual receptors are the people who will be affected by changes in views at these places, and they are usually grouped by what they are doing at those places (for example residents, motorists and recreational users).
GLVIA3 states that the nature of visual receptors, commonly referred to as their sensitivity, should be assessed in terms of the susceptibility of the receptor to change in views/visual amenity and the value attached to particular views. The nature of the effect will be assessed in terms of the size and scale, geographical extent, duration and reversibility of the effect. These aspects will all be considered to form a judgement regarding the overall significance of effect.
As part of the Alwen Wind Farm Scoping Report (August 2018), a list of viewpoints was selected to provide a representative range of viewing distances and viewing experiences for the Alwen Forest Wind Farm, including views from settlements, points of interest and sequential views along routes. The list of viewpoints has since been refined following comments received from consultees which were summarised by the Planning Inspectorate in the Scoping Direction (September 2018), and are set out in Table 11.2.
As illustrated on the Comparative ZTV (Figure 11.2), the majority of the area which shows theoretical visibility generated from the grid connection, is also covered by theoretical visibility from the wind farm. Therefore, the viewpoints from the list in Table 11.2 that lie within the 4 km Study Area and shown to have theoretical visibility of the grid connection proposal, will provide representative views. These are Viewpoints 1, 2, 6 and 10. Their distance from the nearest part of the grid connection corridors is provided in Table 11.2 and their locations are included on the ZTVs (Figure 11.1 and 11.2).
Alwen Forest Wind Farm Grid Connection 31
Table 11.2: List of LVIA viewpoints
Approx. Approx. Distance to Distance Nearest Reason for No. Name Easting Northing to Part of Grid Selection Nearest Connection Turbine Corridor
1 Llyn Brenig 296700 354728 0.5 km 0.4 km Represents views of recreational Visitor Centre receptors at the Visitor Centre. Clocaenog LVIA VP05. Brenig Tip Height Extension LVIA VPE. 2 Alwen Dam 295552 352888 1.3 km 1 km Represents views of recreational receptors on the Alwen circular walk, near the dam car park and picnic area. 3 Alwen Trail 292827 355468 1.8 km -- Represents views of Footbridge recreational receptors on the footbridge crossing the Alwen Reservoir. 4 Alwen Circular 291498 354617 2.1 km -- Represents views of Walk recreational receptors in the hills above Alwen Reservoir. Located within Hiraethog SLA. Clocaenog LVIA VP11. 5 Track between 292681 356810 2.4 km -- Represents views of Llyn Aled and road users travelling A543 between Llyn Aled and the A543.
6 Brenig 298297 357236 3 km 2.3 km Represents views of Archaeological recreational Trail receptors on the trail on the eastern side of Llyn Brenig. Pant y Maen LVIA VP15.
7 A543 near 295208 358971 3.6 km -- Represents views of road users on the Sportsman’s A543. Clocaenog Arms LVIA VP07. Pant y Maen LVIA VP16.
8 Swch y Llan, 294928 348452 4.6 km -- Represents views of Cerrigydrudion residents in the small settlement of Cerrigydrudion in the Merddwr valley. Clocaenog LVIA VP09.
Alwen Forest Wind Farm Grid Connection 32
Approx. Approx. Distance to Distance Nearest Reason for No. Name Easting Northing to Part of Grid Selection Nearest Connection Turbine Corridor
9 Rhydlydan 289279 350844 5.1 km -- Represents views of residents in the small settlement of Rhydlydan in the Merddwr valley. 10 Craig 301857 351970 6.3 km 3.1 km Represents views of Bronbanog recreational receptors at a summit on the Hiraethog Trail within the Clocaenog Forest. Clocaenog LVIA VP01. Brenig Tip Height Extension LVIA VPK. 11 Footpath above 290500 345595 8.3 km -- Represents views of Cadair Benllyn recreational receptors in Snowdonia National Park. Clocaenog LVIA VP13. Brenig Tip Height Extension LVIA VPI. 12 Foel Goch 295357 342285 10.8 km -- Represents views from a hill summit (Arenigs) above Y Bala. 13 Carnedd y 287120 344596 11.1 km -- Represents views of recreational Ffiliast receptors at a popular summit on the edge of Snowdonia National Park. 14 B4407 near 282757 347295 12.5 km -- Represents views from a road within Ysbyty Ifan Snowdonia National Park. 15 Liberty Hall 308559 340889 18.7 km -- Represents views of recreational receptors at a popular summit in the Clwydian Range and Dee Valley AONB. 16 Moel Famau 316069 362683 21.2 km -- Represents views of recreational receptors at a popular summit in the Clwydian Range and Dee Valley AONB. Clocaenog LVIA VP16. Brenig Tip Height Extension LVIA VPQ. Pant y Maen LVIA VP5.
Wireframe only.
Alwen Forest Wind Farm Grid Connection 33
Approx. Approx. Distance to Distance Nearest Reason for No. Name Easting Northing to Part of Grid Selection Nearest Connection Turbine Corridor
17 Moel y Gamelin 317622 346514 22.9 km -- Represents views of recreational receptors at a popular summit in the Clwydian Range and Dee Valley AONB.
Wireframe only.
18 Carnedd Moel 270544 354668 22.9 km -- Represents views of Siabod recreational receptors at a popular summit in Snowdonia National Park. Clocaenog LVIA VP 24. Brenig Tip Height Extension LVIA VPV. Pant y Maen LVIA VP23.
Wireframe only.
19 Cefn y Capel 270881 358372 23 km -- Represents views of recreational receptors at a popular summit in Snowdonia National Park.
Wireframe only.
20 Carnedd 268386 364367 27.3 km -- Represents views of recreational Llywelyn receptors at a popular summit in Snowdonia National Park.
Wireframe only. 21 Summit of 261000 354400 32.5 km -- Represents views of Snowdon recreational receptors at a popular summit in Snowdonia National Park.
Wireframe only.
Assessment of the visual effects of the proposed grid connection route will be based on analysis of the ZTVs, field studies and examination of visualisations. The proposed grid connection route will be included in the wind farm visualisations for Viewpoints 1, 2, 6 and 10. Visualisations for each of the assessment viewpoints will be prepared in line with SNH guidance20. Where forestry is proposed for removal as part of the proposed wind farm development and supporting grid connection, this would be modelled on the
20 Scottish Natural Heritage (February 2017) Visual Representation of Wind Farms Guidance. Version 2.2
Alwen Forest Wind Farm Grid Connection 34
photomontages for the closest viewpoints, where changes would be most visible (which will include VPs 1, 2, 6 and 10). It is considered that visualisations will not be required if the grid connection route is underground.
It is acknowledged that the Comparative ZTV (Figure 11.2) shows additional theoretical visibility where only the proposed grid connection corridor is visible. The majority of this area is to the east of the corridors encompassing parts of Clocaenog Forest. As discussed in Paragraph 11.1.3, the ZTVs have been modelled on 'bare earth' and do not take into consideration existing blocks of vegetation. Viewpoints have therefore not been selected from these areas to the east of the corridors as forestry will obscure views of the grid connection route.
Question 13: Do consultees consider that the proposed viewpoints set out above are appropriate to inform the visual assessment, and that the suggested presentation of visualisations is proportionate?
11.5. Cumulative Assessment No other grid connection projects have been identified that would give rise to likely significant cumulative effects, however the Alwen Forest Wind Farm, and other wind farms in the area may result in significant cumulative effects with the grid connection.
Table 11.3 shows the criteria for which wind farms should be included as part of the cumulative assessment for the Alwen Forest Wind Farm and Grid Connection. By adopting this criteria it will ensure that the focus in the assessment is on potentially significant cumulative interactions. Consideration of the cumulative effect of the proposed Alwen Forest Wind Farm grid connection with other wind farm applications will only be applicable for those wind farms within 4 km from the proposed grid route, beyond which significant cumulative effects with the grid route are unlikely to occur.
Table 11.3: Wind Farms to be considered in cumulative assessment
Tip Height (m) Turbine no. 0-5 km >5-35 km Single turbine No No <20 More than one turbine No No Single turbine Yes No ≥20 <50 More than one turbine Yes No Single turbine Yes No ≥50 More than one turbine Yes Yes
Source: LUC Question 14: Do consultees agree no cumulative assessment of the proposed grid connection is required?
12. Hydrology, Geology and Hydrogeology
12.1. Introduction This section of the scoping report outlines the information currently available and presents the baseline conditions applicable to the hydrological, hydrogeological and geological environment in the surrounding region of the Alwen Forest Wind Farm grid connection.
The intention of this scoping report is to introduce the project and provide the competent authority and its advisors with sufficient information (where it currently exists) on the likely impacts of the Alwen Forest Wind Farm Grid Connection on individual receptors and important features at this stage. The intended approach will allow for an EIA that focusses on only those aspects of the proposed development that are
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likely to have a significant effect on known hydrological, hydrogeological and groundwater receptors, as well as those receptors that are currently unknown.
A hydrological baseline desktop review has been undertaken. The information gained from desktop review has been presented in the following sections.
Where the impacts on important hydrological, hydrogeological and geological features (whether it be direct or indirect) from the Alwen Forest Wind Farm Grid Connection are not likely to cause a significant effect these have been detailed below. For each of these features, it is proposed that these receptors are ‘scoped out’ and thus not included within the EIA.
The potential impact on any identified hydrological or hydrogeological receptor arising from the development of the proposed grid connection, irrespective of method i.e. overhead or underground would be considered in the ES. This would identify any potential impacts and consideration of appropriate mitigation measures to minimise any effect.
The structure of this section notes the guidance and legislation, methodologies to be used and identifies the results from the work undertaken to date. Table 12.6 summarises the results in relation to the proposed wind farm grid connection and highlights whether or not the receptor will be included within the EIA.
12.2. Assessment Methodology
Legislation, Guidance and Consultation The assessment will be undertaken in accordance with the following legislation and guidance.
International Legislation and Policy The assessment will take into account the requirements of the Water Framework Directive (2000/60/EC) (WFD). The WFD aims to protect and enhance the quality of surface freshwater (including lakes, rivers and streams), groundwater, groundwater dependent ecosystems, estuaries and coastal waters. The key objectives of the WFD relevant to this assessment are: • To prevent deterioration and enhance aquatic ecosystems; and • To establish a framework of protection of surface freshwater and groundwater.
National Legislation and Regulations This assessment will take into account the following legislation and policy: • The Water Environment (Water Framework Directive) (England and Wales) Regulations 2017; • Land Drainage Act 1994; • Flood and Water Management Act 2010; • Water Act 2014; • The Pollution Prevention and Control (England and Wales) Regulations 2000; • The Water Supply (Water Quality) Regulations (Wales) 2018; • The Private Water Supplies (Wales) Regulations 2017; • The Waste (England and Wales) (Amendment) Regulations 2012; • Part IIa of the Environment Protection Act 1990; and • The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017.
Policy & Guidance The following regional policies will also be taken into account during the assessment: • Planning Policy Wales (Edition 10) – December 2018; • Technical Advice Note 8: Renewable Energy;
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• Technical Advice Note 15: Development and Flood Risk; • Conwy County Borough Council Local Development Plan; and • Denbighshire County Council Local Development Plan.
Table 12.1 lists other guidance and best practice documentation which will be considered as part of this assessment.
Table 12.1: Guidance and good practice
Topic Source of Information NRW Pollution Prevention PPG 1 Understanding your environmental responsibilities - good Guidelines (PPG’s)* environmental practices GPP 2: Above ground oil storage tanks GPP 4: Treatment and disposal of wastewater where there is no connection to the public foul sewer GPP 5: Works and maintenance in or near water PPG 6: Working at construction and demolition sites GPP 8: Safe storage and disposal of used oil GPP 13: Vehicle washing and cleaning GPP 21: Polluting incident response planning Construction Industry CIRIA C692 Environmental Good Practice on site (third edition) Research and Information CIRIA C753 The Sustainable Drainage Systems (SuDs) Manual Association (CIRIA) CIRIA C532 Control of Water Pollution from Construction sites CIRIA C624 Development and Flood Risk – guidance for the construction industry CIRIA C648 Control of Water Pollution from Linear Construction Projects CIRIA C689 Culvert Design and Operation Guide Other Guidelines Scottish Renewables Joint Publication, (2019) Good Practice During Wind Farm Construction Version 4 FCE, SNH, (2010), Floating Roads on Peat Scottish Renewables, Joint Publication (2012), Development of Peatland: Guidance on the Assessment of Peat Volumes, Reuse of Excavated Peat and the Minimisation of Waste *A review plan for the PPGs is currently underway. The review will result in a replacement guidance series, Guidance for Pollution Prevention (GPPs). It is aimed that the new series will provide environmental good practice guidance for the whole UK, and environmental regulatory guidance directly to Northern Ireland, Scotland and Wales21
Consultation Throughout the EIA stage, on-going consultation will be undertaken with relevant stakeholders, including NRW, Dŵr Cymru, Conwy County Borough Council and Denbighshire County Council to confirm that the approach to the assessment is acceptable.
21 Net Regs (2019). Guidance for Pollution Prevention (GPPs) - Full List. [Online]. Available from: http://www.netregs.org.uk/environmental-topics/pollution-prevention-guidelines-ppgs-and-replacement- series/guidance-for-pollution-prevention-gpps-full-list/ [Accessed: 12/09/2019]
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Desk Based Study A desk-based study has been undertaken in order to establish the hydrology, hydrogeological and geological conditions underlying the area of the proposed wind farm grid connection. A detailed review of documentation and data sources has been undertaken, as detailed in Table 12.2.
Further studies will be undertaken to verify the hydrological, hydrogeological and geological conditions to support the baseline considerations along the route of the proposed wind farm grid connection.
Table 12.2: Baseline Information Sources
Topic Sources of Information Topography 1:25,000 Ordnance Survey Mapping 1:50,000 Ordnance Survey Mapping Designated Nature and NRW Designated Sites (http://naturalresources.wales/guidance-and- Conservation sites advice/environmental-topics/wildlife-and-biodiversity/find-protected- areas-of-land-and-seas/designated-sites/?lang=en) [Accessed 12/09/2019] Solid and Superficial Geology 1:50,000 Solid and Superficial Geology data provided by the British Geological Survey (BGS) Soils and Peat UK Soil Observatory Map Viewer (http://www.ukso.org/mapViewer.html) [Accessed 12/09/2019] Surface Water Hydrology 1:10,000 OS Raster Data 1:50,000 OS Raster Data Flooding NRW Long Term Flood Risk Map (https://naturalresources.wales/evidence-and-data/maps/long-term- flood-risk/?lang=en) [Accessed 12/09/2019] Water Quality NRW Water Watch Wales Map Gallery (http://waterwatchwales.naturalresourceswales.gov.uk/en/) [accessed 12/09/2019] NRW River Basin Management Plans (https://naturalresources.wales/evidence-and-data/research-and- reports/water-reports/river-basin-management-plans- published/?lang=en) [Accessed 12/09/2019] Water Resources 1:50,000 OS Raster Data Conwy and Denbighshire Council PWS Data Request Hydrogeology 1:625,000 Hydrogeology data provided by the British Geological Survey (http://mapapps2.bgs.ac.uk/geoindex/home.html) [Accessed 12/09/2019]
Assessment of Effects The greatest risk of the proposed grid connection affecting the hydrological, geological and hydrogeological environment will occur during the construction phase, with effects reduced during the operational and decommissioning phases. Taking this into account the following issues will be addressed as part of the EIA: • Changes to existing drainage patterns; • Effects on baseflow; • Effects on run-off rates; • Effects on erosion and sedimentation;
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• Effects on groundwater levels; • Effects on water resources; • Effects on impediments to flow; • Flood risk; • Pollution risk; • Effects on local geology; • Effects on hydrological integrity of peat bodies; and • Effects on groundwater and surface water quality (including Groundwater Dependent Terrestrial Ecosystems (GWDTE’s)).
The assessment will be carried out in accordance with the methodology defined in Section 5, whereby the residual significance of an identified adverse effect will be determined based on the sensitivity of the receptor and the magnitude of change The sensitivity of hydrological, hydrogeological and geological receptors will be defined as presented in Table 12.3.
Table 12.3: Definition of sensitivity of the receiving environment
Sensitivity DEFINITION High International importance. High quality and rarity, regional or national scale and limited potential for substitution/replacement. National importance. Receptor with a high quality and rarity, local scale and limited potential for substitution/replacement or receptor with a medium quality and rarity, regional or national scale and limited potential for substitution / replacement. Medium Regional importance. Receptor with a medium quality and rarity, local scale and limited potential for substitution/replacement or receptor with a low quality and rarity, regional or national scale and limited potential for substitution / replacement. Low Local importance. Receptor with a low quality and rarity, local scale. Environmental equilibrium is stable and is resilient to changes that are greater than natural fluctuations, without detriment to its present character.
Source: Natural Power The assessment will be undertaken assuming the implementation of industry good practice mitigation. An outline of this mitigation is provided in the following paragraphs.
Good Practice Embedded Mitigation Mitigation will follow the well-established principles of industry good practice to prevent or minimise effects on the surface and groundwater environment. The mitigation requirements will be dependent upon the final design and the construction methodology for the proposed wind farm grid connection. It is acknowledged that the route may comprise wholly or partially of OHL or underground cables.
Regardless of the construction methodology, the following good practice principles will be included as part of the embedded mitigation: • Drainage – all runoff derived from works associated with the proposed wind farm grid connection will not be allowed to directly enter the identified natural drainage network. All runoff will be adequately treated via a suitably designed drainage scheme with appropriate sediment and pollution management measures, if applicable. • Storage – all soil/peat stockpiles as well as equipment, materials and chemicals will be stored well away from any watercourses. Chemical, fuel and oil stores will be sited on impervious bases with a secured bund.
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• Vehicles and Refuelling – standing machinery will have drip trays placed underneath to prevent oil and fuel leaks causing pollution. Where practicable, refuelling of vehicles and machinery will be carried out in designated areas, on an impermeable surface, and well away from any watercourse. • Maintenance –maintenance to construction plant will be carried out in designated areas, on an impermeable surface well away from any watercourse or drainage feature, unless vehicles have broken down necessitating maintenance at the point of breakdown, where special precautions will be taken. • Welfare Facilities – on-site welfare facilities will be adequately designed and maintained to ensure all sewage is disposed of appropriately. This may take the form of a soakaway or tankering and off-site disposal depending on the suitability of the site for a soakaway and only with prior agreement with NRW/Local Planning Authority. • Cement and Concrete – The use of fresh concrete and cement is considered unlikely. Both are very alkaline and corrosive and can be lethal to aquatic life. The use of wet concrete in and around watercourses will be preferentially avoided, any watercourse crossings are likely to use pre-cast concrete sections for example. If necessary, it will be carefully controlled. • Monitoring Plan – all activities undertaken as part of the proposed development will be monitored throughout the construction phase. Such monitoring will be to ensure environmental compliance. • Contingency Plans – plans will ensure that emergency equipment is available on site i.e. spill kits and absorbent materials, advice on action to be taken and who should be informed in the event of a pollution incident. • Training – All relevant staff personnel will be trained in both normal operating and emergency procedures, and be made aware of sensitive areas on site.
Further details on specific mitigation requirements will be provided as part of the ES. This is likely to include the preparation of a site specific Construction Environmental Management Plan (CEMP) as well as appropriate and applicable technical appendices. It should be acknowledged that this CEMP would be an outline CEMP in certain elements of its detail, due to the requirement of detailed engineering design which may not be available at the stage of the application, but nonetheless, will be guided by good practice and legislation.
12.3. Desk Based Studies The following section summarises the desktop survey work undertaken to date to inform the hydrological, hydrogeological and geological assessment. Through the desk study the existing site conditions underlying the proposed wind farm grid connection have been established and are outlined below.
Designated sites The proposed wind farm grid connection corridors are located to the south and east of the Mynydd Hiraethog SSSI which is designated for its area of blanket bog, dry heath and a mixture of heath and mire habitats.
The designated site is hydrologically disconnected from the proposed wind farm grid connection with the exception of a small area on the eastern side of Llyn Brenig. Until the route and construction methodologies are confirmed, it is possible that construction works associated with the proposed wind farm grid connection could disrupt the designated features of the SSSI.
Hydrology Due to its linear nature the proposed wind farm grid connection corridors is located across multiple catchments. From the proposed on-site substation within Alwen Forest Wind Farm the southern section of the proposed wind farm grid connection travels in a west to east direction and is located within the catchment of the Afon Alwen. From NGR SH 004 547, the proposed wind farm grid connection travels in
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a south to north direction to the existing Clocaenog Forest Wind Farm substation and is located within the catchments of the Afon Corris, Afon Clywedog and Afon Concwest.
No infrastructure associated with the proposed wind farm grid connection is located within the catchment of Alwen Reservoir.
Due to the proximity of the proposed wind farm grid connection to mapped watercourses further assessment will be required to determine the level of impact from water quality, flooding and potential pollution.
Flood risk A qualitative flood risk assessment has been undertaken where the risks of flooding have considered all sources and reference to NRW’s Flood Map22. The assessment has considered the risk to the proposed wind farm grid connection as well as the increase in flooding downstream caused by the development.
Fluvial and Pluvial Flooding
A review of NRW’s Flood Map indicates that the floodplain of the Afon Alwen, downstream of Llyn Brenig has a medium (between 1 in 100 year event to a 1 in 30 year event) to high risk (less than a 1 in 30 year event) of flooding. No other surface watercourses along the route of the proposed wind farm grid connection are mapped to be at risk of fluvial flooding.
Multiple watercourses along the route of the proposed wind farm grid connection are mapped to be at medium (between 1 in 100 year event to a 1 in 30 year event) to low (between 1 in 1000 year event to a 1 in 100 year event) risk of surface water flooding.
The online mapping also provides details for the extent of flooding in the unlikely event that the Llyn Brenig dam was to fail. The area of flooding is significant and extends beyond the channel of the Afon Alwen.
Tidal Flood Sources
The proposed development is greater than 10 km away from the nearest coast. Given the distance to the coast and the topographical position of the proposed development it will not be affected by tidal flooding and therefore scoped out of the assessment.
Groundwater Flood Sources
Flooding can also result from high groundwater levels if the water table rises above the surface level. Groundwater flooding happens in response to a combination of already high groundwater levels (usually during mid- or late-winter) and intense or unusually lengthy storm events. Groundwater flooding is difficult to predict as it rarely follows a consistent pattern. The response time between rainfall and groundwater flooding is also relatively long.
Groundwater flooding is often associated with the shallow unconsolidated sedimentary aquifers that over lie non-aquifers. Such aquifers are susceptible to flooding as the storage capacity within these deposits is often limited and direct rainfall recharge can be relatively high, subsequently increasing the water levels within the groundwater.
Flooding from Artificial Drainage
Artificial drainage associated with commercial forestry is likely to be prevalent along the route of the proposed wind farm grid connection. There is the potential that this could cause some localised flooding by increasing runoff rates to the watercourse they drain to within the surrounding area.
Due to proximity of the proposed wind farm grid infrastructure to mapped watercourses which have been determined as being at risk from fluvial flooding further assessment on the potential impacts will be required.
22 NRW. (2018) Long term flood risk. [Online]. Available from https://naturalresources.wales/evidence-and- data/maps/long-term-flood-risk/?lang=en [Accessed 13/09/2019].
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Soils The distribution of soils across the proposed wind farm grid connection is dependent upon land use, geology, topography and hydrological regime of the area. Information on the site soils has been provided by the UKSO23 and is presented below in Table 12.4.
Table 12.4: Summary of soil types
Generalised Soil Type Parent material Slowly permeable, wet acid upland soil, with peaty surface Mudstone and Sandstone Very acid, upland loamy soil, with peaty surface. Glacial Till
The information indicates that peaty soils are the dominant type within the area of the proposed development.
Based on the presence of peaty soils it is recommended that phase 1 peat surveys are carried out on a 100 m grid within the corridor of the proposed wind farm grid connection. This information will be used to inform the need for further targeted surveys, construction methodology and mitigation requirements. Detailed surveys could include: • 50 m gridded points for construction compounds; • 50 m spacing along centreline of the grid connection route, with 10 m offsets along underground cable sections and any sections of new track; and
Geology A review of the 1:50,000 scale British Geology Society (BGS) dataset indicates that the proposed wind farm grid connection is underlain by the geological units presented in Table 12.5.
Table 12.5: Solid and Superficial Geology
Element Type Comments Solid Geology Denbigh Grits Formation, Sedimentary These sedimentary rocks are marine in origin. Mudstone, Siltstone, and rock They are detrital and comprise coarse- to fine- Sandstone grained slurries of debris from the continental shelf flowing into a deep-sea environment, forming (Southern extent of proposed distinctively graded beds. wind farm grid connection corridor) Denbigh Grits Formation: Sedimentary These sedimentary rocks are marine in origin. Sandstone rock They are detrital and comprise coarse- to fine- grained slurries of debris from the continental (Southern extent of proposed shelf flowing into a deep-sea environment, forming wind farm grid connection distinctively graded beds. corridor) Nantglyn Flags Formation: Sedimentary These sedimentary rocks are marine in origin. Mudstone and Siltstone rock They are detrital and comprise coarse- to fine- grained slurries of debris from the continental shelf flowing into a deep-sea environment, forming distinctively graded beds.
23 UKSO (2018). UK Soil Observatory map viewer. [Online].Available from http://www.ukso.org/mapViewer.html [Accessed 20/06/2018]
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Element Type Comments (Central extent of proposed wind farm grid connection corridor) Elwy Formation: Mudstone, Sedimentary These sedimentary rocks are marine in origin. Siltstone and Sandstone rock They are detrital and comprise coarse- to fine- grained slurries of debris from the continental (Northern extent of proposed shelf flowing into a deep-sea environment, forming wind farm grid connection) distinctively graded beds.
Superficial Geology Till Superficial Majority of the proposed wind farm grid deposit connection is underlain by Till. These sedimentary deposits are glacigenic in origin. They are detrital, created by the action of ice and meltwater, they can form a wide range of deposits and geomorphologies associated with glacial and inter-glacial periods during the Quaternary. Peat Superficial Small isolated pockets of peat are mapped in the deposit vicinity of the proposed wind farm grid connection. These sedimentary deposits are lacustrine and palustrine in origin. They comprise accumulated (and detrital) organic material, forming beds and lenses within lagoons, bogs and swamps. Alluvium Superficial Small areas in the vicinity of the proposed wind deposit farm grid connection, along riparian corridors of watercourses, are underlain by Alluvium. These sedimentary deposits are fluvial in origin. They are detrital, ranging from coarse- to fine- grained and form beds and lenses of deposits reflecting the channels, floodplains and levees of a river.
It is noted that no specific geological features of interest have been identified along the proposed wind farm grid connection, as such this can be scoped out of the assessment. Although having an understanding of the underlying bedrock and superficial geology is pivotal for the effectiveness of the construction design of the proposed wind farm grid connection, specific mitigation to protect the geodiversity during construction, operation and decommissioning is not required. The information of the local geology will be utilised in the assessment of groundwater dependent terrestrial ecosystems (GWDTEs).
Hydrogeology The 1:625,000 scale BGS Hydrogeological Map24 indicates that the proposed wind farm grid connection is underlain by a low productivity aquifer associated with the Wenlock Rocks (undifferentiated) (southern and central section) and Ludlow Rocks (undifferentiated). The sedimentary interbedded sandstone
24 BGS (2018). BGS hydrogeology 625K. [Online]. Available from http://www.bgs.ac.uk/products/hydrogeology/maps.html [Accessed: 12/09/2019]
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conglomerate would give rise to limited groundwater. Flow is virtually all through fractures and other discontinuities.
At this stage, no assessment has been made of the groundwater dependency of the habitats located along the proposed wind farm grid connection. A thorough review and inclusion of appropriate assessment will be included in the ES to determine the characteristics of the hydrogeological environment and its suitability to support GWTDEs. The ES will be prepared with cognisance of the habitats and National Vegetation Classification (NVC) assessment completed as part of the Ecology assessment.
Fisheries A review of fisheries information will determine whether this is an identified receptor which will require assessment.
Water Resources A review of base mapping and aerial photography confirms the presence of properties along the proposed wind farm grid connection. It is highly probably that these properties utilise a private water supply (PWS). A formal data request will be issued to the local authorities to confirm the presence of any private water abstractions within 1 km of the grid route corridor. As the presence of private water supplies cannot be confirmed at this stage, these will be further assessed as part of the EIA. The assessment will focus on identifying property source locations and assessing the potential effects on the source in relation to it’s topographical, hydrological or hydrogeological connectivity to the proposed wind farm grid connection
12.4. Impact Assessment Based on the findings of the baseline study and whether the significance of any effect on receptors can be quantified. Table 12.6 identifies what is proposed to be scoped in and out of the assessment. The impact assessment would follow the methodology set out in Section 5.
Table 12.6: Proposed Scoping Topics
Scope in Topic or out Reason Designated Sites Scope In The designated site (SSSI) is located downslope of the proposed wind farm grid connection and it is possible that there will be direct and/or indirect impacts from a hydrological perspective. Site Hydrology Scope In The assessment will be undertaken that considers the potential impacts of the proposed wind farm grid connection on water quality, flood risk and potential pollution. Flood Risk Scope In Whilst a desk based assessment has been provided above, further assessment will be required due to mapped water features in the proximity to the proposed wind farm grid connection being at risk of fluvial and surface water flooding Peat and Soils Scope In The initial desktop study identifies extensive areas of peat soils. Further assessment will likely be required to inform a carbon balance assessment, peat management plan and peat slide risk assessment. Information on peat and soils will also be utilised for production of a GWDTE assessment. Geology Scope Out No specific mitigations to protect geodiversity are required. Review of the local geology information will be considered for the GWDTE assessment. Hydrogeology Scope In Assessment will be required to confirm the presence of GWTDE on site based habitat, soils and hydrogeological information.
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Scope in Topic or out Reason Fisheries Scope In At this stage it is unclear whether fisheries is an identified receptor. Water Resource Scope In PWS have been identified within the surrounding area as part of Alwen Forest Wind Farm scoping report with further assessment likely to be required as part of the works associated with the proposed wind farm grid connection.
13. Cultural Heritage
13.1. Introduction This section presents the proposed scope of work for the Cultural Heritage assessment for the Alwen Forest Wind Farm Grid Connection. The purpose of the assessment is to identify the potential effects of the proposed development on the historic environment and cultural significance of the area in which the development is located. The heritage impact assessment will follow policy and best practice guidance in order to establish a robust and transparent analysis of the issues. The approach adopted will follow a standard staged process consisting of: • baseline survey to identify known and potential historic assets, • design iteration to avoid constraints and minimise potential impacts on the historic environment, • comparative analysis to determine which historic assets might be affected by the proposed development, • field survey and analysis to establish the heritage significance of important affected assets, characterising the nature and magnitude of impacts, • design of mitigation measures, and an • assessment of the residual effect on the historic environment.
13.2. Environmental Baseline and Potential Sources of Impact
Baseline Conditions Three Designated Historic Assets (DHAs) of national importance lie within the preferred grid route corridors (Figure 13.1). These are the Hafoty Wen Ring Cairn (Scheduled Monument DE283), Twr yr Hill Round Barrow (Scheduled Monument DE088) and the Mynydd Hiraethog/Denbigh Moors Registered Landscape of Special Historic Interest in Wales (Historic Landscape Wales No. 39).
A further five Scheduled Monuments (Cae Ddunod Camp DE076, Bwlch-Du Round Barrow DE085, Hen Ddinbych Circular Platforms DE086, Ffridd Brynhelen Enclosures and Fields DE228, and Circular Platforms North West of Hen Ddinbych DE087) and three Grade II Listed Buildings (Pont-yr-Alwen 19342, Alwen Dam 19351 and Pont-y-Rhuddfa 19352) lie within 2 km of the grid corridors (Figure 13.2).
Two versions of the Mynydd Hiraethog/Denbigh Moors Registered Landscape of Special Historic Interest in Wales (Historic Landscape Wales (HLW) No. 39) exist. One version is represented within the published register and is located almost entirely within the Mynydd Hiraethog SSSI. A more detailed map of this HLW designation divides it into 15 character areas which have been created following the results of survey work by the Clwyd Powys Archaeological Trust (CPAT) (and this is the area shown on Figure 13.2). The HLW designation has been made to preserve an increasingly rare historic landscape of upland heather moorland that was managed as a grouse moor and shooting estate in the early 20th century, which had its origins in the Neolithic and Bronze Age (and possibly earlier). During medieval and post-medieval times summer grazing and seasonal occupation was followed by some permanent settlement, for farming and peat cutting.
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Cadw’s advice in response to a query over the exact boundaries of the HLW during the scoping of the Alwen Forest Wind Farm in 2018 was; ”In some cases, Historic Character Area edges can fall outside the extent of the landscape areas on the Register. In planning terms, the Register is non-statutory, and so is the information from characterisation that is intended to support it. It will be a matter for the planning or other competent authority undertaking an EIA, or the PI Inspector concerned, to determine where a precise edge should be drawn.”
It is proposed that the extent of the registered landscape as identified in the study by CPAT is used in this assessment.
Question 15: Are consultees happy with this approach to the assessment of the Registered Landscape?
There are 283 records of non-designated historic assets listed by the CPAT Historic Environment Record (HER) within a 2 km buffer from the grid route corridors (as shown on Figure 13.2). This number includes 16 within the corridors, and a further five on the edge or adjacent. There are also 93 sites recorded by the National Monument Record Wales (NMRW) and 22 by the Royal Commission of Ancient and Historic Monuments Wales (RCHAMW) within the same 2 km buffer. Some of these duplicate the HER or DHA data, but most are assets of local importance.
Potential Sources of Impact Effects on the historic environment can arise through direct physical impacts, impacts on setting or indirect impacts: • Direct physical impacts describe those development activities that directly cause damage to the fabric of a heritage asset. Typically, these activities are related to construction works and will only occur within the site. • An impact on the setting of a heritage asset occurs when the presence of a development changes the surroundings of a heritage asset in such a way that it affects (positively or negatively) the heritage significance of that asset. Visual impacts are most commonly encountered but other environmental factors such as noise, light or air quality can be relevant in some cases. Impacts may be encountered at all stages in the life cycle of a development from construction to decommissioning but they are only likely to lead to significant effects during the prolonged operational life of the development, as in the case of OHL. • Indirect impacts describe secondary processes, triggered by the development, that lead to the degradation or preservation of heritage assets. For example, changes to hydrology may affect archaeological preservation; or changes to the setting of a building may affect the viability of its current use and thus lead to dereliction.
Decommissioning should not result in further damage as the ground disturbance would already have occurred during the construction phase, and therefore is scoped out of the assessment.
13.3. Method of Assessment
Legislative, Policy and National Guidance Framework The assessment will comply with Welsh legislative and planning policy frameworks and apply Cadw’s relevant guidance to ensure the EIA is undertaken in a robust manner. • The Historic Environment (Wales) Act 2016 is the primary statutory tool for protecting historic assets and sustainable management of the historic environment. It is designed to enable greater transparency into decisions taken on the historic environment and to make it a statutory requirement for information on the historic environment to be safe-guarded for the public good. • National policy within Wales is set out in Planning Policy Wales Edition 10, December 2018 (PPW), in which Section 6.1 sets out the policies intended to ensure a proposed development is sustainable and to prevent unnecessary harm to historic assets.
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• PPW is supported by Technical Advice Note 24: The Historic Environment (May 2017) which is designed to assist local authorities with developing their local plans and for determination of planning applications or listed building consent in relation to historic assets. The Welsh Ministers and Planning Inspectors will consider these guidance documents when considering the proposal. • The two principal guidance documents that will be followed in this assessment are those produced by Cadw on behalf of the Welsh Government for managing historic assets: Heritage Impact Assessment in Wales (May 2017) and the Setting of Historic Assets in Wales (2017). • Cadw’s Conservation Principles for the sustainable management of the historic environment in Wales (March 2011) will also be used to establish objective assessment of the value and significance of historic assets within and surrounding the proposed development site. • In relation to the Registered Landscape of Special Archaeological Interest in Wales, Natural Resources Wales (NRW)’s Guide to Good Practice on Using the Register of Landscapes of Historic Interest in the Planning and Development Process (2007) will be used. • The Chartered Institute for Archaeologists’ standard and guidance for Historic Environment Desk- Based Assessment (January 2017) provides national quality standard for the baseline study.
Baseline Desk Study It is proposed that the cultural heritage assessment will employ two study areas. The Inner Study Area will comprise the route option corridors and a 2 km buffer from the outer edge of the corridor. The Inner Study Area will allow the development of the local historic environment to be understood in detail, to enable an assessment of the significance of known assets, and to identify the potential for currently unknown assets to occur, within the boundary of the proposed development.
Analysis of effects resulting from change to their setting will be carried out on all historic assets within the Inner Study Area and on DHAs within 2 - 4 km of the grid route option corridors (‘the Outer Study Area’). This reflects the study area used for the LVIA which is based on a “worst case” visibility for OHL (Paragraph 11.1.3. In line with the LVIA, if underground cable is proposed then only the Inner Study Area will be used, to identify potential direct impacts on archaeological remains and construction phase effects on the setting of DHAs.
Intangible cultural heritage for the combined study areas would also be considered at this stage, to include for example potential artistic or literary associations, sacred space, or local traditions and customs.
Baseline Field Study and Virtual Modelling A site inspection will be carried out along the chosen grid connection route, including a 100 m buffer to allow for micrositing to establish the condition of historic assets and identify the potential for the existence of additional assets not currently identified. It will also identify the contemporary existing environment (including historic and modern developments, and land-use including operational wind farms and single turbines) to help understand the setting of historic assets and the degree of change that the proposed development might introduce.
To assist with the impact assessment a staged approach will be undertaken. Field inspections will be made after a filtering exercise to identify those historic assets that would not experience visual change, and that can therefore be scoped out. This would be achieved by comparison of mapped historic assets against the Zone of Theoretical Visibility (ZTV) data and aerial imagery. For those assets which show a potential change to their setting by the development being visible, further analysis would be undertaken to assess the level of impact. The ZTV mapping uses a bare earth model and even when it suggests potential visibility of the proposed development from historic assets, intervening vegetation and structures might screen views, which will be confirmed through field inspections.
Question 16: Do consultees have any comments regarding the approach noted above for the methodology, and relevant legislation, policy and guidance?
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Assessment of Heritage Significance Analysis of the historic assets and historic mapping will allow synthesis and interpretation of the historic development of the site and enable the heritage significance to be established in accordance with Cadw’s Heritage Impact Assessment in Wales (section 4.2) and Conservation Principles for the sustainable management of the historic environment in Wales. This analysis will also establish what comprises the setting for the historic assets, and what elements of that setting contribute to how the asset is experienced, understood and appreciated. Assessment of the heritage significance (sensitivity) of the asset would use the criteria in Table 13.1 (the HLW is not included as this has a specific assessment methodology and scoring mechanism that needs to be applied (ASIDOHL2), so is itemised separately below).
Table 13.1: Levels of heritage significance Heritage Significance Explanation Importance of the asset Criteria Very high World Heritage Sites and other assets of equal international importance. High Grade I and II* Registered Parks and Gardens, Scheduled Monuments, Protected Wreck Sites, Registered Battlefields, Grade I and II* Listed Buildings, and undesignated heritage assets of equal importance. Medium Conservation Areas, Grade II Registered Parks and Gardens, Grade II Listed Buildings, heritage assets on local lists and undesignated assets of equal importance. Low Undesignated heritage assets of lesser importance. Negligible Negligible or no heritage significance. Unknown Further information is required to assess the potential of these sites.
Source: Headland Archaeology
Initial Input to Design Iteration and Mitigation Analysis of Geographic Information System (GIS) layered data about the historic environment (DHAs, non-designated historic assets in CPAT and RCHAMW datasets) has been used to identify the preferred grid route corridors.
Further analysis of historic environment data will be provided to the design team to assist with avoiding or minimising both direct and indirect effects on historic assets. Where potential adverse impacts on cultural heritage are identified, measures to prevent, reduce and/or where possible offset will be proposed.
Assessment of Potential Impacts The proposed development would result in a change to the existing baseline, and change might be considered as impacts according to the degree of change in relation to heritage significance. In accordance with EIA regulations, the assessment would identify impacts and effects as direct or indirect, adverse or beneficial, and short-term, long-term or permanent. Direct impacts are those which physically alter an asset and therefore its heritage significance; indirect impacts are those which affect the heritage significance of an asset by causing change within its setting. Application of Cadw’s Managing: Setting of Historic Assets in Wales will require a four stage process in assessment of impacts: • Stage 1: Identify the Historic Assets • Stage 2: Define and Analyse the Setting • Stage 3: Evaluate the Potential Impact of Change or Development • Stage 4: Consider Options to Mitigate the Impact of a Proposed Change or Development
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Magnitude of impact will be assessed with reference to the criteria set out in Table 13.2.
Table 13.2: Magnitude of impact Magnitude of impact Definition Magnitude of Impact Guideline Criteria High beneficial Elements of the asset’s physical fabric which would otherwise be lost, severely compromising its heritage significance, are preserved in situ; or Elements of the asset’s setting, which were previously lost or unintelligible, are restored, greatly enhancing its heritage significance. Medium beneficial Elements of the asset’s physical fabric which would otherwise be lost, leading to an appreciable but partial loss of heritage significance, are preserved in situ; or Elements of the asset’s setting are considerably improved, appreciably enhancing its heritage significance; or Research and recording leads to a considerable enhancement to the archaeological or historical interest of the asset. Low beneficial Elements of the asset’s physical fabric which would otherwise be lost, leading to a slight loss of heritage significance, are preserved in situ; or Elements of the asset’s setting are improved, slightly enhancing its heritage significance; or Research and recording leads to a slight enhancement to the archaeological or historical interest of the asset. Negligible The asset’s fabric and/or setting is changed in ways which do not beneficially or adversely affect its heritage significance. Low adverse Elements of the asset’s fabric and/or setting which are of very limited relevance to its significance are lost or changed, resulting in a very slight loss of heritage significance; or Elements of the asset’s fabric and/or setting which contribute to its heritage significance are minimally affected, resulting in a very slight loss of heritage significance. Medium adverse Elements of the asset’s fabric and/or setting which contribute to its significance are affected, but to a limited extent, resulting in an appreciable but partial loss of the asset’s heritage significance. High adverse Key elements of the asset’s fabric and/or setting are lost or fundamentally altered, such that the asset’s heritage significance is lost or severely compromised. Source: Headland Archaeology
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Assessment of Potential Effects Following a design freeze the EIA will assess the potential direct effects for heritage assets from construction activities within the grid connection route. If the final proposal is for OHL the EIA would also assess the potential effects from the operational phase, principally visibility, to historic assets within the Inner Study Area from significant change to their settings. If underground cable is chosen, then no significant operational phase effects are predicted and this will be scoped out of the assessment. Within the Outer Study Area assessment would be focussed on DHAs of the highest heritage significance (Table 13.1) that following the filtering process are considered to have potential for more than minimal visual change.
Analysis of data gathered during the desk study and site visit layered within a GIS, combined if necessary with photographs and wireframe visualisations of the topography and proposed development (produced by the LVIA consultants) will be used to facilitate assessment.
These assessments will be carried out using professional judgement, taking into account designations and heritage significance as assessed against national standards. Significance of effect will be based on a combination of heritage significance (in other disciplines sometimes referred to as sensitivity of the receptor) and magnitude of impact. The significance of effect matrix is presented in Table13.3 below and relates the heritage significance to the magnitude of impact (incorporating contribution from setting where relevant) to establish the likely significance of effect.
Effects of Major or Moderate significance are considered to be “significant effects” in EIA terms, those of Minor or Negligible significance are considered not be significant in EIA terms, but will be described in the assessment as they would still be a material planning consideration.
Table 13.3: Significance of Effect
Magnitude of Heritage Significance Impact Very High High Medium Low High beneficial Major Major Major or Moderate or
Moderate Minor
Medium beneficial Major Major or Moderate Minor Moderate or minor Low beneficial Major or Moderate or Minor Negligible
moderate minor Enhancement Neutral/None Neutral/nil Neutral/nil Neutral/nil Neutral/nil Neutral/ nil Low adverse Major or Moderate or Minor Negligible moderate minor Medium adverse Major Major or Moderate Minor
moderate or minor
High adverse Major Major Major or Moderate or
Moderate Minor Harm
Source: Headland Archaeology
ASIDOHL 2 The introduction of the grid connection into, or in proximity to, the HLW would have direct and indirect impacts, on the historic landscape. Although this has not prevented permission for Clocaenog or Brenig wind farms, NRW has raised concerns over wind farm applications and their potential impact on HLWs in other parts of Wales. Development within an HLW is not forbidden, but the designation presents a further level of potential harm to the historic environment that would need to be robustly assessed. A full ASIDOHL2 would be required to complement any EIA and related planning submission, and ultimately the
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public benefit that might derive from the scheme would be an essential element in determining whether the development would receive permission.
A single ASIDOHL2 assessment is proposed, combining the wind farm and grid elements of the development. This allows the development as a whole to be assessed.
Question 17: Are consultees in agreement with combining the wind farm and grid connection for a single AIDOHL2 assessment?
Cumulative Effects Cumulative effects on the significance of heritage assets may occur where the grid connection results in an effect on the significance of a heritage asset and other developments also have an effect on the same asset.
No other grid connection projects have been identified that would give rise to likely significant cumulative effects, however the Alwen Forest Wind Farm, and other wind farms in the area may result in significant cumulative effects with the grid connection.
Table 11.3 shows the criteria for which wind farms should be included as part of the cumulative assessment for the Alwen Forest Wind Farm and Grid Connection. By adopting this criteria it will ensure that the focus in the assessment is on potentially significant cumulative interactions. Consideration of the cumulative effect of the proposed Alwen Forest Wind Farm grid connection with other wind farm applications will only be applicable for those wind farms within 4 km from the proposed grid route, beyond which significant cumulative effects with the grid route are unlikely to occur.
Question 18: Are consultees in agreement with the proposed levels of significance, magnitude of effect and significance of effect matrices?
Question 19: Are consultees in agreement with the proposed identification of schemes for cumulative assessment?
Consultation Consultation with respect to the method of assessment employed and the cultural heritage assets will be undertaken with Cadw (SMs, Grade I and II* LBs and Registered Parks and Gardens, and ASIDOHL2 (also with NRW)), and Conwy and Denbighshire Councils (Grade II LBs and RPGs, conservation areas), and CPAT (non-designated heritage assets). This will be recorded within the ES.
Matters Scoped Out It is not proposed that cultural heritage issues in general would be scoped out, but where for example the “bare earth” ZTV indicates no visibility of the development from a historic asset or from areas where the asset’s significance can be appreciated, this would allow the asset to be scoped out early in the assessment process. All such instances where a historic asset is scoped out of further assessment will be clearly explained within the ES.
As noted above, decommissioning should not result in further damage as the ground disturbance would already have occurred during the construction phase, and therefore is scoped out of the assessment.
Operational phase effects will be scoped out if the proposal taken forward is for underground cable.
Question 20: Are consultees in agreement with the approach to scope out certain cultural heritage aspects?
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14. Traffic and Transport
14.1. Introduction This section of the scoping report presents the proposed scope for assessing the effects that may arise upon the environment as a result of traffic and transport movements associated with the construction, operation and decommissioning of the grid connection.
14.2. Methodology
Study Area For the purposes of considering the potential environmental effects arising from construction, operation and decommissioning traffic, the study area needs to be sufficiently large to include the need for access into various sections of the chosen route alignment.
The B4501 is a local authority maintained road that runs north-south from Cerrigydrudion in the south to the A543 to the north. There is an additional spur road off the main north-south running B4501 located to the north of Llyn Brenig. This additional spur road off the B4501, which runs east-west to Denbigh, is also named as the B4501. The B4501 spur is single carriageway, except for a 4 km section of single track which runs from its junction with the A543 running west towards the main B4501.
The two grid corridor options run from the SPEN (Clocaenog) Substation close to the B4501 east-west spur, through Clocaenog Forest to the proposed Alwen Forest Wind Farm substation off the north-south running B4501.
It is anticipated that the main construction traffic deliveries will enter the north of the grid route from the B4501 east-west spur and the south of the grid route from the north-south B4501. The proposed access to Alwen Forest Wind Farm will be off the main B4501 running north-south from Cerrigydrudion.
The study area therefore consists of the: • A543 from the A5 trunk road in the south to the A544 in the north, • B4501 (north-south) road from Cerrigydrudion (on the A5 trunk road) in the south to the A543 in the north, • B4501 (east-west) spur road from the B4501 north-south road in the west to the B5435 in the east.
Approach to the EIA The ‘Guidelines for the Environmental Assessment of Road Traffic’ (EART), published by the Institute of Environmental Assessment (IEA) is used to assess the environmental impact of traffic generated by a proposed development. The EART suggests that two rules can be used as a screening process to delimit the scale and extent of the assessment: • Rule 1 – Include highway links where traffic flows would increase by more than 30% (or the number of Heavy Goods Vehicles (HGVs) would increase by more than 30%); • Rule 2 – Include any other specifically sensitive areas where traffic flows would increase by 10% or more. (IEA Guidelines Paragraph 3.20 defines sensitive area as including accident blackspots, conservation areas, hospitals, links with pedestrian flows etc.).
Where the predicted increase in traffic flow is lower than these thresholds, the significance of the effects will be stated to be low or insignificant, and further detailed assessments will not be warranted. Where the predicted increase in traffic flow results in a high significance then further mitigation will be required in order to minimise the potential impact.
It should be noted that these guidelines are intended for the environmental impact assessment of long- term impacts of road traffic associated with major new developments such as industrial estates and supermarkets. In terms of a grid route development, this would be equivalent to the operational phase
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rather than the construction phase. The volume of traffic generated during the operational phase of a grid route is considered negligible as during normal operation the connection would generally be unattended with the exception of periodic site visits to carry out routine inspections and preventative maintenance. However, in the absence of other guidance, the EART guidelines are also used to assess the temporary transport flow during construction.
The following sub-section identifies the nature of the potential impacts that may occur as a result of the traffic generated by the grid route. The impacts are considered under three distinct phases and impacts identified that may be associated both with overhead lines and undergrounding.
Construction Phase Construction vehicle movements can be separated into five distinct scenarios. These are: • Those associated with the bulk importation of materials to a central construction compound and which may require deliveries by HGV; • Those associated with the transhipment of material (e.g. wood poles) from the central construction compound to satellite compounds or working areas at locations along the route, which is likely to require two, daily, deliveries by a single HGV given the length of the poles (in the case of overhead); • Those associated with the transportation of plant and machinery from satellite compounds to working locations i.e. the pole location (in the case of overhead) or trench (in the case of underground). Deliveries could be via HGV, Large Goods Vehicles (LGV) or 4x4; • The movement of construction workers along the route alignment using private vehicles or LGV; • The removal of logged timber from the construction area, depending upon the final route alignment selected and whether the timber crop would have a commercial value.
In each of the scenarios listed above, impacts to sensitive receptors are likely to be indirect, secondary, short-term and reversible. The likelihood of the impacts occurring will be based upon the presence or otherwise of sensitive receptors along the routes travelled, the frequency and timing of vehicle movements and the nature of the vehicles involved.
Operation and Maintenance Phase The operation of the connection will result in no regular vehicle movements. The maintenance of an overhead section of the connection is likely to involve periodic line inspections (approximately bi-annually) supplemented by the occasional replacement of insulators or poles (the poles generally have a design life of 40 years but can last longer, insulators are normally replaced between 30-40 years). Underground sections are less likely to require ongoing inspection and maintenance.
It is assumed that traffic movement associated with inspection and maintenance will be occasional and limited in number to a level which would not exceed 10% of average daily flows along any part of the network. As such it is proposed to scope out operational and maintenance impacts from this assessment.
Decommissioning Phase Decommissioning will include for removal of the overhead lines and poles (in the case of overhead) and potentially the removal of the cable in the case of underground. Decommissioning of the connection would not take place before the decommissioning of the wind farm, and as such, a minimum period of 35 years is assumed before decommissioning takes place. Due to the changes in the baseline situation which may have occurred by the time that the connection is decommissioned it is considered impractical to assess the likely environmental effects. Based on the Department for Transport, Road Traffic Forecasts25 (2018), background traffic levels are predicted to increase rather than decrease into the future. Hence, percentage
25 Available online from: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/740399/ road-traffic-forecasts-2018.pdf (last accessed 25/09/2019)
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impacts at the time of decommissioning are likely to be lower than at construction and as such it is considered that the construction impacts will represent a worse case position at decommissioning. It is therefore proposed to scope out decommissioning effects.
Impact Mitigation Mitigation will be identified for any potentially significant construction impacts. Mitigation will be primarily in the form of a draft Traffic Management Plan (TMP) which will set out the agreed routing, timing, signing, access locations and access routes relating to the grid connection and wind farm.
Question 21: Do consultees have any comments in relation to scoping out traffic and transport operation and decommissioning effects?
15. Noise
15.1. Introduction Environmental, or community noise is a broad term that encompasses noise emitted from many sources, including road, rail, air traffic, industry, construction, public work and neighbourhood noise. All of these sources potentially contribute adversely to the overall noise environment. It is therefore reasonable to expect communities to be sensitive to any deterioration in their acoustic environment as a result of a proposed development.
The proposed Alwen Forest Wind Farm Grid Connection will introduce new sound sources into the local area in the form of construction plant and potentially operational for OHL (if this method of connection is opted). This section, therefore, considers the potential for adverse noise impacts to occur from both the construction, operation and decommissioning of the proposed wind farm grid connection.
15.2. Legislation and Guidance Technical Advice Note 11 (TAN 11)26, as amended by CL-01-15 ‘Updates to Tan 11 Noise,’27 provides guidance for local authorities in Wales on minimising noise impacts from new developments. It outlines the considerations to be taken into account when determining planning applications for both noise- sensitive developments and for noise generating developments. The TAN 11 is supported by the ‘Noise and Soundscape Action Plan 2018–2023’,28 which outlines the Welsh public sector’s strategic policy direction in relation to noise and soundscape management.
Construction Noise Construction site noise is regulated through Section 60 of the Control of Pollution Act 1974 (COPA 1974) 29 and BS 5228:1997 ‘Noise and vibration control on construction and open sites. Code of practice for basic information and procedures for noise and vibration control’ parts 1 to 5 (BSI, 1997) is the approved Code of Practice under COPA74. The standard, however, was updated in 2009 and amended in 2014 and both the TAN and the Action Plan endorses the use of the newer BS 5228:2009 +A1:201430 as appropriate guidance for noise and vibration control in respect of construction operations. As such it is proposed that
26 Wales, Planning, (1997) Technical Advice Note (TAN) 11 Noise. Wales: Welsh Government 27 Minister for natural Resources, (2015) CL-01-15 Updates to Tan 11 Noise - Noise Action Plan (2013-18) Commitments. Wales: Welsh Government 28 Welsh Government, (2018) Noise and Soundscape Action Plan 2018 – 2023. Wales: Crown 29 HM Government (1974). Control of Pollution Act 1974 Chapter 40. London: Her Majesty's Stationery Office. 30 BSI (2014). BS 5228-1:2009+A1:2014 Code of practice for noise and vibration control on construction and open sites. Noise. UK: British Standards Institute.
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BS 5228:2009 +A1:2014 is the most appropriate version of the standard to refer to for any construction noise assessment. Annex E of the standard provides example assessment methods to determine the likelihood of potential significant effects. For residential receptors, these are based on the anticipated change in existing noise levels for daytime, weekend, evening and night-time periods. For public open space, the assessment considers the change in noise levels over a longer period, typically no less than one month.
Operational Noise There are no specific references within the TAN 11 to electrical infrastructure developments, such as substations, overhead lines etc. however, with regards to industrial developments TAN 11 states that operational noise ‘…can be assessed, where the Standard is appropriate, using guidance in BS 4142…’
Although BS 4142:2014 +A1:201931 can be used to assess overhead line noise during dry weather conditions, the standard excludes measurements taken during precipitation events, and since the majority of overhead line noise is generated during wet conditions, the BS standard is not appropriate in the situations when overhead line noise can be most prominent. Consequently, an in-house assessment method was developed by National Grid and this is detailed in the document, ‘A Method for Assessing the Community Response to Overhead Line Noise,’ (TR(T)94)32. Although the TAN 11 does not specifically reference the National Grid assessment method, it is referred to in NPS EN-5 as an appropriate methodology to use for assessment. No other assessment methods are available or endorsed to assess operational noise from overhead lines, however a detailed method for the calculation of overhead line noise is presented in the CIGRÉ Technical Brochure, ’TB 020 Interferences Produced by Corona Effect of Electric Systems’33. The TR(T)94 is the assessment method that would be used.
15.3. Noise Sensitive Receptors Noise Sensitive Receptors (NSRs) are properties, people or fauna which are sensitive to noise and, therefore, may require protection from nearby noise sources. The areas around both corridors are sparsely populated, however, the closest receptors, which have a high level of sensitivity, are residential receptors that are located approximately 20 m from the closest edge of proposed Corridor 1 and between 125 m and 150 m from the closest edge of proposed Corridor 2. Other residential NSRs have been identified at greater distances from both corridors, however it is assumed that if noise levels are acceptable at the closest receptors then it would also be within acceptable levels at properties located further away. NSRs with a lower level of sensitivity include a number of public footpaths and cycling routes within Clocaenog Forest and other similar public open space.
15.4. Construction Noise Effects Construction activities will vary depending on the requirements for overhead lines or underground cabling and construction noise levels will vary throughout the construction period as construction activities, plant and locations vary.
For overhead line construction the amount of required plant is relatively small, typically consisting of an excavator, a tractor and trailer to deliver the poles to site and the vans and 4x4 vehicles used by the contracted workers. The installation of the poles requires a foundation hole to be excavated, the pole lifted
31 BSI (2019). BS4142:2014 +A1:2019 Methods for rating and assessing industrial and commercial sound. UK: British Standards Institute 32 National Grid (2018). TR(T) 94 – A Method for Assessing the Community Response to Overhead Line Noise. Wales: National Grid 33 CIGRÉ (1974). TB 020 Interferences Produced by Corona Effect of Electric Systems. Description of Phenomena – Practical Guide for Calculation. France: Conseil International des Grands Réseaux Électriques / International Council on Large Electric Systems
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into position and then the hole backfilled with the excavated material. As such, construction activities in any one location will be limited in duration and adverse noise effects are anticipated to be negligible.
For underground cable installation, this may simply consist of trenching, laying the cable and backfilling, which is unlikely to result in any significant adverse noise impacts, however, there is the possibility that Horizontal Directional Drilling (HDD) may be required in order for the cables to cross under obstructions such as watercourses, roads etc. Where this occurs, significantly more equipment would be required and noise levels from these activities would be both higher and longer in duration than trenching operations.
It is assumed that decommissioning activities would be very similar to the construction activities, requiring minimal plant to be employed to remove both overhead line posts or undergrounded cables.
It has already been agreed that construction noise will not be assessed for the Alwen Forest Wind Farm and this is detailed within Section 7.6 of the Alwen Forest Wind Farm DNS: EIA Scoping Direction, which states;
‘CCBC [Conwy County Borough Council] and DCC [Denbighshire County Council] agree that construction noise can be scoped out of any noise assessment, and the Inspectorate is content with this approach. DCC advises that the construction method statement should include noise abatement measures and the Inspectorate endorses this approach. The applicant should also ensure that the ES clearly sets out the justification for scoping out construction noise.’
With due regards to the above, it is proposed that if HDD activities or similar are required, then this will be included within the ES Noise Chapter and assessed following the guidance presented in BS 5228; however, due to the limited activities and duration associated with the installation or decommissioning of overhead cabling, or the trenching and backfilling of underground cabling, other construction activities can be scoped out and excluded from the ES as it is likely to result in a non-significant effect in the professional opinion of TNEI Group. However, if activities were to occur very close to houses/caravans then there could be a significant effect of a very short duration i.e. a couple of days.
Question 22: Do consultees agree with the scope of the construction noise assessment i.e. that construction noise effects can be scoped out from the ES unless HDD or similar activities are required for the undergrounding of cabling?
15.5. Operational Noise Effects Audible noise can be generated from the operation of an overhead line due to variations in field strength on the conductor surfaces and occurs as part of a ‘corona discharge’. Although transmission lines are designed to operate below the threshold for corona discharges, it can come about through irregularities in the surface of the conductor. Two types of operational noise can occur as a result; these are termed ‘dry noise’ and ‘wet noise’.
Dry Noise occurs due to a build-up of dirt and debris on the conductors. It can be minimised through quality control during both manufacturing and installation, however, during long periods of dry weather, wind borne debris can stick to the conductor, which in turn may generate some audible noise. The noise is characterised by low level ‘crackling’ and is more likely to occur when the line is new and liable to be oily. During periods of rainfall, however, the line is washed clean of debris thereby reducing the level of dry noise that can be produced.
Wet Noise is the more common and louder form of noise generation and this occurs when droplets of water form on the line. As well as a crackle, a 100 Hz ‘hum’ can be produced, the level of which varies with rain rate. The level of wet noise that is generated can be predicted and assessed using the methods detailed in TR(T)94 and CIGRE TB 020.
TB 020 states at 6.2.6 Lower Voltage Lines;
‘The conductors of lines at voltages lower than 30 kV operate at such low gradients … that no corona effect occurs even in rain. Any case of interference is solely caused by the insulators’
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And at 6.2.2 Validity Limits of the CIGRE Calculation Formula the document states;
‘The formula proposed, based exclusively on conductor corona effect, would give incorrect values for lines of nominal voltage less than 200 kV. In fact, in this case, the overall interference level of the line is generally rather to line hardware, insulators etc’.
Accordingly, for 33 kV lines such as those proposed, no operational noise effects are anticipated from the conductor and only the hardware (fixings, insulators) need considering. In this regard, however, TR(T) 94 states;
‘Only noise from discharge activity on the conductors is considered in this report. Noise may also arise from discharges on insulators and fittings, but this noise is minimised by the use of preferred designs. In addition, point noise sources (such as insulators and fittings) are less often intrusive and if complaints arise these can usually be remedied.’
The specification of all hardware will be undertaken in accordance with well-established SP Energy Networks (SPEN) specifications for lines up to 33 kV on wood poles.
With due regards to the above, considering that noise from the lines will be negligible and that preferred designs specified by SPEN will be used to specify all hardware, no adverse operational noise effects are anticipated. Accordingly, it is proposed that operational noise from overhead lines is scoped out of the EIA.
No operational noise effects would occur as the result of underground cables.
Question 23: Do consultees agree that the effects of operational noise can be scoped out of the EIA?
16. Forestry
16.1. Introduction This section sets out the approach which would be used to integrate the proposed Alwen Forest Wind Farm grid connection into the existing woodland structure. The methodology will differ subject to the use of OHL or underground cables along the route. With this decision yet to be made, the different methodologies for OHL and underground cables are addressed below.
A grid connection felling plan would be prepared and submitted as an integral part of the wider Alwen Forest Wind Farm felling plan, setting out the forestry felling and management requirements, including any potential replanting, associated with the construction and operation of the proposed development.
Each of the proposed Alwen Forest grid connection routes traverse significant areas of commercial forestry land. In the western section of the grid connection corridor, the connection to the Alwen Forest Wind Farm lies within land owned by DCWW but managed by NRW on behalf of the Welsh Ministers. The Scottish Power Energy Networks (SPEN) Clocaenog Substation, in the east of the proposed grid connection corridor, lies within Clocaenog Forest, part of the Welsh Government Woodland Estate, managed by NRW. One of the proposed wind farm grid connection corridors also passes through a section of Brenig Forest, owned and directly managed by DCWW.
These forested areas consist primarily of commercial conifers with all growth stages being present, from recently felled or replanted areas, to stands of intermediate age and mature trees. Where the proposed wind farm grid connection routes run adjacent to existing road networks within these forest blocks, a significant element of pre-existing roadside edge ‘open ground’, containing scattered broadleaf regeneration is also present.
In the UK there is a strong presumption against permanent deforestation unless it addresses other environmental concerns. The integration of the proposed development into the Alwen and Clocaenog Forest Design Plans will be a key part of the development process.
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16.2. Consultation The main forestry consultee is NRW. They would be consulted throughout the development to ensure that the proposed changes to the forestry are appropriate and address the requirements of any policy and guidance. Consultation with DCWW will also be required should the proposed wind farm grid connection that runs through Brenig Forest becomes a preferred option.
16.3. Legislation and Guidance The forestry proposals will be prepared in accordance with current industry best practice and guidance including, but not limited to:
• Forestry Commission (2017). The UK Forestry Standard: The Government's Approach to Sustainable Forestry, Fourth Edition, Forestry Commission, Edinburgh.
• SEPA (2013). SEPA Guidance Notes WST-G-027 Management of Forestry Waste.
• SEPA (2014). LUPS-GU27 Use of Trees Cleared to Facilitate Development of Afforested Land.
• UKWAS (2018). The UK Woodland Assurance Standard, Fourth Edition, UKWAS, Edinburgh.
• Welsh Government (2018). Woodlands for Wales – The Welsh Governments Strategy for Woodlands & Trees Strategy. Welsh Government, Cardiff.
Question 24: Do consultees have other best practice guidance that we should be considering?
16.4. Methodology Commercial forests are sustainably managed and constantly changing through landowner activities, market forces and natural events such as windblow or pest and diseases. Commercial forestry is therefore not being regarded as a receptor for a formal impact assessment, and in this context would not usually be assessed in terms of the ‘significance’ of effects. Instead it would be a factual assessment describing the changes to the forest structure resulting from the incorporation of the proposed wind farm grid connection into the forest. This would include the changes to, for example, the woodland composition and felling programmes. The significance of any effects from forest felling would be assessed in the relevant chapters of the ES including Ornithology; Landscape and Visual; Hydrology, Geology and Hydrogeology; Ecology; and Traffic and Transport.
The forestry baseline will describe the crops existing at the time of preparation of the ES. This would include current species; the planting year; felling and restocking plans; and other relevant woodland information. It would be prepared from existing forest records; desk-based assessments; site visits; and aerial photographs.
There is potential for changes to the forest structure resulting from the proposed development, with consequential implications for the wider felling and restocking plans across the forest area. Areas of woodland would need to be felled for the construction and maintenance of clear wayleaves along the proposed wind farm grid connection. The use of either an OHL or underground cable will determine the minimum required wayleave clearance within each crop, with these minimum wayleave requirements being maintained as open ground for the life of the proposed development.
Subject to consultation, overhead lines may require a corridor of up to two times the terminal height of adjacent trees, creating unplanted corridors of up to 140 metres (for an assumed terminal tree height of 35 metres). Underground cables would require a felled corridor of up to 10 metres that would remain unplanted.
An assessment will be made on a crop by crop basis along the length of the proposed wind farm grid connection, considering crop age, felling timetable and existing wind firm edges, to assess whether the minimum felling corridor could be cleared, or whether a larger area of felling would be required in order to
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maintain crop stability. Terminal height assessment of crops adjacent to the OHL wayleaves may also identify opportunities for a reduction in the minimum felling corridor required.
Where the need for felling beyond the minimum wayleave requirement is identified, these areas would either be restocked within the life of the proposed development or managed via adaptive forest management in a way that benefits both commercial forestry and environmental objectives.
Each of the proposed wind farm grid connection corridors consist of existing features, such as roads within the woodlands, that could be followed along part of their length. In these areas assessment of the surrounding crops will inform which side of the road cables should be run in order to minimise forestry impacts. Identifying and utilising the existing corridors of open ground, which are present along these verges, will help to minimise the overall tree clearance impact along the route of the proposed wind farm grid connection.
The Welsh Governments’ ‘Woodlands for Wales’ strategy (2018) sets out a number of outcomes sought from existing and new woodlands in Wales. This includes the following statement ‘there is a strong presumption against the permanent removal of woodland…’. Whilst the removal of woodland for wind farm infrastructure, including its associated grid connection, is for the life of the proposed development only, the Applicant would consult with NRW Energy Delivery Programme team on the mitigation options in possibly locating and planting equivalent areas of woodland. The resulting changes to the woodland structure and any requirement for compensation planting to mitigate against any woodland loss would be considered in the context of the published guidance and policy with regards to forestry.
The changes to the forests for a particular development are regarded as site specific and it is considered that there are no cumulative forestry issues to be addressed. The felling and restructuring of the forest areas which result from the proposed development would be similar, in both scale and activity, to the routine forestry management operations which will be ongoing in other forestry properties across the region.
Question 25: Are consultees in agreement with the proposed methodology for forestry?
17. Socio-Economics
17.1. Introduction The demonstration of socio-economic and community impacts has become a more prominent issue for the onshore wind sector in recent years. We therefore consider it essential that this ES includes a socio- economic assessment to determine the benefits for the Welsh economy and benefits for local communities. The socio-economic section of the ES will consider the wind farm and associated grid infrastructure.
Research on the effects of grid connections, distinct from wind farms is limited to studies which consider higher voltage connections of a scale which are considered to have little relevance to this project34. In terms of tourism effects, the review of literature evidence suggests that overall, the research tends to support the premise that wind farm development has not resulted in a serious negative economic impact on tourism and could even have wider positive impacts. The most relevant and recent research on the
34 National Grid (2014) A Study into the Effect of National Grid Infrastructure Projects on Socio Economic Factors, https://www.nationalgrid.com/sites/default/files/documents/38741- A%20study%20into%20the%20effect%20of%20National%20Grid%20major%20infrastructure%20pro jects%20on%20socio-economic%20factors.pdf [Accessed 21/10/19]
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economic impact of wind farms on tourism was published by the Welsh Government in February 201435. The research outlines a number of key findings which suggests that there is little evidence to suggest wind farms have had/or have, a detrimental impact on tourism across Wales. Furthermore, a more recent national tracker survey36 outlined that support for renewable energy has been consistently high during the tracker at around 80 – 84%%, with 82% expressing support for the use of renewables, whilst opposition to renewables was very low at 3%, with only 1% strongly opposed. It is intended therefore to scope out assessment of tourism from the EIA.
17.2. Methodology We propose that the socio-economic assessment would be integral with the wind farm assessment, based upon 3 economic boundaries (local, regional and national economy) but reflective of the comparatively minor element the grid would comprise and will include the following: • assess the existing economic environment (baseline) using official data on population, industrial structure, unemployment and economic activity levels, income and earnings; • assess the potential economic effects during the development and construction phase of the project including direct employment, supplier effects and income effects; • assess the potential economic effects during the operation of the wind farm including direct employment, supplier effects and income effects; • consider and report on mitigation and management measures which could be employed to minimise any negative impacts and maximise potential positive impacts.
17.3. Impact Assessment Table 17.1 summarises the topics to be scoped in and scoped out of the assessment.
Table 17.1: Impact Assessment Topics
Assessment Scope in or out? Socio-economics Scope in Tourism Scope out
Source: Natural Power Question 26: Are consultees in agreement with the proposed methodology for socio-economic assessment and that tourism is scoped out?
18. Health and Public Safety
18.1. Lightning The danger to human or animal life from lightning strike via a grid connection is rare since lightning is directed down to the earth. Maintenance of the OHL and/or cables would not be undertaken during high lightning risk weather conditions. Lightning will not be assessed in the ES.
35 Welsh Government (2014) Study into the Potential Economic Impact of Wind Farms and Associated Grid Infrastructure on the Welsh Tourism Sector, https://gov.wales/docs/desh/publications/140404economic- impacts-of-wind-farms-on-tourism-en.pdf [Accessed 26/06/2018] 36 Energy and Climate Change Public Attitude Tracker, Wave 30, July 2019.: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/817872/BEI S_Public_Attitudes_Tracker_Wave_30_key_findings.pdf [Accessed 09/09/2019]
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18.2. Health & Safety The assessment of the safety aspects of the construction, operation and decommissioning of the grid connection will consider the health and safety of construction workers and risks to safety of members of the general public. CBCC and DCC will be consulted with regard to the location of any hazardous sites within the vicinity of the proposed development.
The CEMP (Paragraph 4.2.25) will detail the environmental mitigation measures that will be implemented during each stage of the construction works and will be in accordance with the CEMP.
Electric & Magnetic Fields There is no specific local or Welsh national planning guidance relative to the consideration of electric and magnetic fields (EMF). National Planning Statement EN-5 does provide guidance that may be material in the case of this grid connection though its primary focus is upon connections with a capacity of 132 kv or greater.
NPS EN-5 describes electric and magnetic fields and notes that their strength decreases rapidly as distance from the line increases. In the case of cables only magnetic fields are created and this again drops rapidly as distance from the cable increases.
NPS EN-5 summarises current guidance on exposure to EMF and concludes that scientific evidence has not proven any causal link between EMF’s and human health, crop damage or to impacts upon natural ecosystems. The Department of Health does not consider that overhead line EMFs constitute a significant hazard to the operation of pacemakers.
Protection against potential EMF effects will be provided by designing the connection in accordance with industry standard specification. At a voltage below 132 kV the proposed connection would comply with relevant exposure limits whilst its operations would require it to comply with appropriate phasing requirements. EMF is considered not to be significant, and it is therefore proposed to scope this topic out from further consideration within the ES.
18.3. Impact Assessment Table 18.1 summarises the topics to be scoped in and scoped out of the health and public safety assessment.
Table 18.1: Impact Assessment Topics
Assessment Scope in or out? Lightning Scope out
Health and Safety Scope out
Source: Natural Power Question 27: Do consultees have any comments regarding scoping out of Health and Safety relating to the grid connection of the proposed Alwen Forest development?
19. Aviation and Existing Infrastructure
19.1. Introduction This section assesses the potential impact of the proposed Alwen Forest Grid Connection on aviation and existing infrastructure and sets out the proposed methods for assessing aviation and existing infrastructure in the ES.
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In terms of aviation, an initial feasibility assessment carried out by Coleman Aviation Ltd considered the potential impact on civil and military aviation interests in the areas. Aviation would be scoped out of the ES for the grid connection.
The cable routes are well outside any aviation infrastructure safeguarding areas and in the worst-case scenario (OHLs supported on 10 m wooden poles) there would not be a requirement for any consultation with aviation stakeholders. By way of justification, the lowest obstacles that require any form of consultation outside aviation safeguarding areas are obstacles of 21.3 m.Civil Aviation Publication 764, Para 4.9 sub-para 2 reads:
“Structures with a maximum height below 300 ft (91.4m) above ground level. In the interest of Aviation Safety, the CAA also requests that any feature/structure 70 ft (21.3m) in height, or greater, above ground level is also reported to the Defence Geographic Centre (DGC). It should be noted that Notices to Airmen (NOTAMs) would not routinely be required for structures under 300 ft (91.4m) unless specifically requested by an aviation stakeholder.”
For information, the Defence Geographic Centre are responsible for updating data used on aviation flying charts, and a notice to airmen (NOTAM) is a notice filed with an aviation authority to alert aircraft pilots of potential hazards along a flight route or at a location that could affect the safety of the flight. The authority in turn provides a means of disseminating relevant NOTAMs to pilots.
19.2. Other Existing Infrastructure Potential impact on other existing infrastructure may include: • Public Rights of Way; • Microwave fixed links and TV and • Water, gas and power lines.
The location of all PRoW will be identified along the two grid corridors. During construction the PRoW will be appropriately managed for health and safety reasons. The majority of PRoW in proximity to the grid corridors are footpaths, the Clwydian Way and the Brenig and Two Lakes trails and the Brenig Archaeological Trail and designated open access land with a bridleway crossing centrally. The Clwydian Way, a 196 km long distance footpath, runs for 500 m through the north section of the grid corridors.
There are numerous NRW promoted recreational routes within the grid connection corridors and its vicinity, as well as the Llyn Brenig Visitor Centre which will be considered as part of the design of the proposed development to minimise potential conflicts and take account of recreational users of the Visitor Centre and the activities it promotes. Detailed discussion is required within NRW and DCWW to ascertain their views of the proposed grid corridors with regard to PRoW and recreational routes. A proposed Access Management Area (AMA) during construction will be prepared to indicate the restrictions for users and any proposed mitigations (through means of alternative routes and enhancement opportunities etc.).
In relation to microwave fixed links, consultation with Ofcom and Joint Radio regarding the proposed Alwen Forest Wind Farm revealed that no links would be affected by the Alwen Forest Wind Farm development. In addition, due to the nature of the grid connection, no microwave fixed links are expected to be impacted by the Alwen Forest development and therefore it is proposed that this is scoped out of the ES.
Terrestrial television reception in the UK is widely available either through the well-established network of standard broadcast services and/or through digital satellite receivers. No interference is expected from the proposed grid connection therefore, it is suggested that TV and radio reception will not be significantly impacted by the proposed grid connection and does not need to be included in the EIA.
As part of the design process data on any existing water, gas and power line infrastructure will be collected and ensured that the grid connection routes takes into consideration these existing infrastructure pieces. Other than ensuring that the design has carefully considered any existing infrastructure locations, no further assessment is proposed in the EIA.
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19.3. Impact Assessment Table 19.1 summarises the topics to be scoped in and scoped out of the existing infrastructure assessment.
Table 19.1: Impact Assessment Topics
Assessment Scope in or out? Aviation Scope out Public Rights of Way and recreational routes Scope in Gas, water and power line Scope in TV and Microwave fixed links Scope out
Source: Natural Power Question 28: Do consultees have any comments regarding scoping out aviation and TV and microwave fixed links relating to the grid connection of the proposed Alwen Forest development
20. Summary, Residual and Synergistic Effects and Mitigation
This section of the ES will summarise the residual effects regarding all of the proposed work in relation to the construction, operation and decommissioning of the proposed development. It will identify all mitigation, including the mitigation by design that will be undertaken to reduce any such effects, should the development be consented.
An assessment of synergistic effects ensures that the assessments provided in the ES for each topic are not considered in isolation. The structure of the ES demonstrates this approach with Section 2 grouping assessments on the biological environment (Ecology and Ornithology). Section 3 considers the physical environment (LVIA, Hydrology, Cultural Heritage, Forestry) and Section 4 considers population and human health (Noise, Traffic, Other Considerations and Socio-economics). It is acknowledged that there are also some potential overlaps between the physical environment and population and human health.
This assessment considers the potential synergistic effect of related residual effects during construction, decommissioning and operation of the Proposed Development. A synergistic effect during decommissioning is considered to be of similar or less significance than that created during construction and therefore they are discussed together below.
We will also give consideration here to any synergistic effects anticipated.
21. ES Accompanying documentation
Non-Technical Summary (NTS) The NTS details the main components of the proposed development and summarises the main findings of the environmental studies carried out to build and operate the proposed development. It is designed to be an easily readable document that will communicate the main elements of the EIA to any interested party without the need for the reader to have specialist background knowledge. It will also contain maps that show the extent and geographical location of the development. This document will be bilingual.
Planning, Design & Access Statement (PDAS) The PDAS seeks to highlight the design principles and concepts behind the proposed development. It will detail how the applicant has applied these principles to the proposed development in tandem with input from consultation activities and will review how successful the proposed development has been in realising the design strategy.
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The PDAS will also provide a commentary of the EIA findings and assess the proposed development accounting for residual effects (both positive and negative) against national policy and legislation, the Development Plan and other material planning considerations relevant to the proposed development.
Pre-Application Consultation (PAC) Report Under article 11 of the Development of National Significance (Procedure) (Wales) Order 2016, a DNS application must be accompanied by a pre-application consultation (PAC) report which provides: • An account of the statutory consultation, publicity, deadlines set, and activities required under section 61Z of the Town and Country Planning Act 1990, including: – Copies of all notices and publications used during the consultation; – Declarations that the relevant notices and publication requirements comply with the Act and Order; – The addresses of those given notice of the proposed application; • a summary of all issues raised by any person consulted under section 61Z(3) of the Act and articles 8 and 9(2), including confirmation of whether the issues raised have been addressed and, if so, how: and • the particulars of all responses received from persons consulted under section 61Z(3) or (4) of the Act, including copies of responses from specialist consultees; and the account taken of these.
Question 29: Do the consultees have any comments regarding the proposed documentation that will accompany the application?
22. Responding to the Scoping Report
The scoping report has identified the baseline resource at the site for different topics and presented where any effects to these may be experienced from the development (either indirectly or directly).
The responses provided by consultees will ensure that they too are in agreement, with the baseline and likely impact assessment so that the ES is focussed. Where features or receptors are deemed to have a possible significant effect the methodologies to assess the impact have been provided for comment. Responses on these would help ensure that the detailed methodology, survey and assessment are carried out with consideration to all statutory consultees and key stakeholders. This approach is in line with good practice in the planning system and an emphasis being communicated at a national level to focus the content of the EIA and ES on key elements identified at the scoping stage.
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Appendix A: Grid Matrix
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Alwen Forest Grid Route Options Matrix (see notes below) North 1 Route length (km) 8.8 Narrative H M L
Landscape Landscape designations inc LANDMAP Cultural Landscape M-H 0.8km of route crosses ‘Conwy Uplands’ (Evaluation: High) 4.6km of route crosses ‘Denbigh Moors’ (Evaluation: High) 3.3km of route crosses ‘Uplands to west of Vale of Clwyd’ (Evaluation: High) 3.3km of route crosses ‘Clocaenog Forest’ (Evaluation: High) Geological Landscape 1.2km of route crosses ‘Gorsedd Bran’ (Evaluation: High) Historic Landscape 8km of route crosses ‘Foel Goch’ (Evaluation: High) Landscape Habitat 2.8km of route crosses ‘Llyn Brenig Upland Heath’ (Evaluation: Outstanding) 2.4km of route crosses ‘Clocaenog Conifer Forest’ (Evaluation: High) Visual and Sensory 1.6km of route crosses ‘’Denbigh and Derwen Hills’ (Evaluation: High) Landscape & visual considerations • At its eastern end the route partly runs through the Tir Mostyn and Foel Goch operational wind farms where turbines provide visual detractors, albeit relatively enclosed by blocks of forest. • The majority of the route follows the B4501 which runs through an area of open moorland and in proximity to where the moorland adjoins Nantglyn Forest in the north. The route traverses the valley slopes associated with Llyn Brenig, across the open moorland which comprises a relatively remote and open character that is particularly valued for its heathland habitat and where vertical features are largely absent. The area of moorland is designated open access land with a public right of way (part of the Clwydian Way long-distance route) running along the southern edge of the B4501, where users are afforded with uninterrupted panoramic views that look beyond gently rising moorland towards Llyn Brenig. • There will be visibility from areas to the south given the elevated position of the route. Within views most of the route will be backclothed by rising landform and forest to the north, however given the rolling nature of the landform some parts of the route will extend above the skyline. This is particularly the case where the route runs along the upper slopes of valleys incised by streams that flow to the north. Sensitive visual receptors to the south of the route include those visiting the Llyn Brenig visitor centre and users of key recreational routes; namely the Clwydian Way long-distance route which runs around the western and north-eastern edges of Llyn Brenig and the Archaeological Trail to the north-east of the reservoir. • Within the proposed Alwen Forest Wind Farm, the route connects to the northern substation. This option is located within an area of forest that has undergone felling, providing a level of visual exposure. The substation will be elevated and visible from areas to the east, although seen against a backdrop comprising retained trees to the west of the substation.
Other landscape considerations 5.2km of route crosses Denbigh Moors Registered Historic Landscape
Cumulative considerations The route is in proximity to the existing Foel Goch and Tir Mostyn wind farms as well as the Clocaenog wind farm which is currently undergoing construction. The route would provide additional vertical features within the landscape; however as the wind turbines are much larger and visible from a greater extent, the route would not result in cumulative issues with the surrounding wind farms. Alternative solution?* It is considered that undergrounding of the route could be an option to minimise adverse visual effects. However there will be some visual scarring across the moorland as a result of the small extent of earthworks required to accommodate underground cables, as well as disturbing the associated heathland habitat. Instead, undergrounding along or under the B4501 would be a better outcome when considering the landscape and visual issues. Discount? - provide reasoning Yes. There will be an adverse impact on the character of the moorland which is a sensitive landscape and the route will form a feature on the skyline in views from the south. Ecology Designations Passes through Mynydd Hiraethog SSSI and M Gors Maen Llwyd North Wales Wildlife Trust nature reserve Desk study records Crossbill and goshawk (Sch.1 species protected from disturbance) may breed in areas of mature plantation. Red squirrel and pine marten are present in North Alwen, and may breed near to the route option. Otter and water vole may be present in streams, surveys may be required if culverting works proposed. Survey findings Black grouse confirmed present (lekking) on heath within the SSSI. Nightjar confirmed present in areas of clearfell and thicket in north Alwen. No dormouse presence confirmed to date (survey work is on-going) Cumulative considerations Cumulative effects may include loss of forestry habitat for red squirrel and pine martin. Distruction or damage to nests of nightjar and disturbance of goshawk and crossbill if construction occurs within the breeding bird season.
Alternative solution?* Discount? - provide reasoning The proposed route follows the B4501 through the SSSI, and therefore is unlikely to result in unfavourable / significant loss of notified habitat. However, Planning Policy Wales 10 includes a presumption against development within a statutory designated site and will require full consideration of impacts on notified features. Need to consider timings to avoid breeding bird season / impacts on black grouse. Hydrology/Geology/Topography Peat/geology Limited soil information available for the National Forest Estate. Data that is available shows that the southern section of the route is located within Flushed Basin Bog and Peaty surface-water gley.
Soilscape data (1:250k scale) identifies the majority of the route underlain by "Very acid loamy upland soils with a wet peaty surface". Stretches of the route in the vicinity of Bryn y Gors-goch area to the Afon Brenig and from the Nant y Fuddai area to the northern end of the route are underlain by "Slowly permeable wet very acid upland soils with a peaty surface".
No geological features of interest noted on the 1:50k BGS superficial geology mapping. Areas of mapped peat align with information presented in above soils information. Majority of route underlain by Glacial Till with riparian corridors underlain by fluvial deposits. Alwen Forest Grid Route Options Matrix (see notes below) North 1 Route length (km) 8.8 Narrative H M L
Hydrology Majority of route is located within the River Dee River Basin District. Northern section of route located within the Western Wales River Basin District.
Majority of cable route is located within the catchment of Llyn Brenig with route to the north within the catchment of Afon Ystrad and Afon Concwest. A small section of the route at its start in the south is located within the catchment of Alwen Reservoir.
Overall WFD 2018 (interim) catchment classification for Afon Brenig, Afon Alwen (above Afon Brenig) and Llyn Brenig is Moderate. Overall WFD 2018 (interim classification for catchment of Afon Ystrad is Good.
Llyn Brenig and catchment of Afon Alwen are designated Drinking Waer Protected Areas.
10 watercourse crossings identified.
Flood risk - no significant risk of fluvial flooding. 1 crossing over the Afon Brenig within Flood Zone 3 (greater than 1 in 30 chance of flooding in each year).
Private water supplies - a number of properties identified beyond the 140 m buffer that could be connected to private water supply.
Slope analysis Slope less than 8⁰ over whole route apart from a 0.5 km section at the eastern end of the route which is >12 ⁰
Cumulative considerations Risk to receptors will be dependent upon final construction method (OHL/underground cable).Cumulative effects may include increased risk to hydrological receptors and loss of peatland habitat. Construction activities increasing risk of pollutants entering drainage network and increased risk of flooding as well as potential to affect private and public water supply assets.
Alternative solution?* No
Discount? - provide reasoning No Cultural Heritage SAMs Corridor passes between Gorsedd Bran Round Barrows to NW and Bwlch-du Round Barrow to SE, the setting of these monuments may be affected
Listed buildings Corridor includes Bwlch-du Grade II Listed Building potential for impacts on this building and its setting
Non-designated heritage assets Corridor includes marker cairn, Pont-Y-Brenig bridge, Afon Fechan Hafod and Pant-y-Maen buildings, standing stone and boundary stones, cairns and stone setting at Tir Mostyn and a possible barrow and a structure near the eastern end. Also includes an area of "turbury" (peat cutting) likely to be confined to within a few fields. Potential for direct impacts on these known assets and on possible un-recorded assets, potential for the setting of the upstanding assets to be affected. Conservation areas None Historic landscapes Within Denbigh Moors Landscape of Special Historic Interest - registered for its interest as an extensive area of managed heather moorland (early 20th century grouse shooting), but including groups of prehistoric monuments on hill summits and the archaeological trail around Brenig reservoir created by relocating heritage assets from the flooded area. ASIDOHL assessment will be required.
Cumulative considerations Potential for cumulative impacts on prehistoric monuments' settings through in combination effects with Alwen and other windfarms
Alternative solution?* Cabling along sections of the B4501 would avoid impacting on setting of the barrows and the listed building
Discount? - provide reasoning Noise Identification of noise receptors Assuming the whole route is overhead one NSR identified that would be required to be considered within an operational noise assessment and a further three NSRs that are just on the edge of our study area buffer and should probably be included for completeness. Cumulative considerations No cumulative impacts are anticipated. Construction noise considerations For overground construction activities a number of properties to the north of the corridor will be required to be assessed, however, construction noise impacts are unlikely to be significant. Significant impacts may, however occur at one property to the south of the corridor at 298720, 358389, though these would be short term impacts only and unlikely to be a material planning consideration. Assuming the proposed Wind Farm Construction Compounds are used it would be advisable to restrict access for material deliveries so that the route south from the A543 only is used. This would stop HGVs from passing by close to dwellings. Alternative solution?* Consideration should be given to realigning the route to move it further to the north away from the receptor at 298720, 358389. Alternatively, undergrounding near this receptor would remove any potential operational noise impacts. Discount? - provide reasoning Socio-economic Tourism/socio-economic receptors Gors Maen Llwyd Nature reserve. Sportsman's Arms 1km.
Public rights of way, National Trails and open access Moorland is designated open access land with a public right of way (part of the Clwydian Way long-distance route) running along the southern edge of the B4501. Adjacent to the Brenig and Two Lakes trails. Runs along edge of Historic Landscape area. Open Access Countryside to the south.
Common land None within route. Cumulative considerations Cumulative interaction with Clocaenog, Tir Mostyn and Brenig wind farms all seen from the trails in the vicinity. Also cumulative interaction with consented Pant y Maen Wind Farm. Alternative solution?*
Discount? - provide reasoning
Note This matrix is for the consideration of the impacts of overhead lines on each route
H M L High, medium or low risk/impact
* Alternative solution - Please include alternative solutions that you think might be appropriate for further investigation, such as alternative location or use of underground cabling rather than overhead. Alwen Forest Grid Route Options Matrix (see notes below) North 2 Route length (km) 8.17 Narrative H M L
Landscape Landscape designations inc LANDMAP Cultural Landscape H 0.8km of route crosses ‘Conwy Uplands’ (Evaluation: High) 3.9km of route crosses ‘Denbigh Moors’ (Evaluation: High) 3.3km of route crosses ‘Uplands to west of Vale of Clwyd’ (Evaluation: High) 3.3km of route crosses ‘Clocaenog Forest’ (Evaluation: High) Historic Landscape 7.3km of route crosses ‘Foel Goch’ (Evaluation: High) Landscape Habitat 2.6km of route crosses ‘Llyn Brenig Upland Heath’ (Evaluation: Outstanding) 2.4km of route crosses ‘Clocaenog Conifer Forest’ (Evaluation: High) Visual and Sensory 1.6km of route crosses ‘’Denbigh and Derwen Hills’ (Evaluation: High) Landscape & visual considerations This route is similar in its alignment as North 1, however instead of following the B4501 to the north-west of Llyn Brenig, it crosses through the centre of the open moorland where the land is at a greater elevation. Being away from the B4501, the landscape is more remote and the elevated position results in the route breaching the skyline when viewed from the sensitive visual receptors to the south.
Other landscape considerations 4.7km of route crosses Denbigh Moors Registered Historic Landscape
Cumulative considerations The route is in proximity to the existing Foel Goch and Tir Mostyn wind farms as well as the Clocaenog wind farm which is currently undergoing construction. The route would provide additional vertical features within the landscape; however as the wind turbines are much larger and visible from a greater extent, the route would not result in cumulative issues with the surrounding wind farms.
Alternative solution?* It is considered that undergrounding of the route could be an option to minimise adverse visual effects. However there will be some visual scarring across the moorland as a result of the small extent of earthworks required to accommodate underground cables, as well as disturbing the associated heathland habitat.
Discount? - provide reasoning Yes. There will be an adverse impact on the character of the moorland which is a sensitive landscape and the route will form a feature on the skyline in views from the south. Ecology Designations Passes through Mynydd Hiraethog SSSI and H Gors Maen Llwyd North Wales Wildlife Trust nature reserve Desk study records Crossbill and goshawk (Sch.1 species protected from disturbance) may breed in areas of mature plantation. Red squirrel and pine marten are present in North Alwen, and may breed near to the route option. Otter and water vole may be present in streams, surveys may be required if culverting works proposed.
Survey findings Black grouse confirmed (lekking) present on heath within the SSSI. Nightjar confirmed present in areas of clearfell and thicket in north Alwen. No dormouse presence confirmed to date (survey work is on-going) Cumulative considerations Cumulative effects may include loss of forestry habitat for red squirrel and pine martin. Distruction or damage to nests of nightjar and disturbance of goshawk and crossbill if construction occurs within the breeding bird season.
Alternative solution?* Routing along B4501 as North 1 Discount? - provide reasoning Yes. There is a significant risk of long-term damage to the notified habitats of the SSSI during construction. This may be overcome if notified habitats (sub- montane heath) can be avoided, and work is completed under a series of method statements. However, it would be difficult to justify the selection of this option on ecological grounds. Disturbance of black grouse is likely if construction occurs in the breeding season, but can be mitigated through seasonal restrictions on work.
Hydrology/Geology/Topography Peat/geology Limited soil information available for the National Forest Estate. Data that is available shows that the southern section of the route is located within Flushed Basin Bog and Peaty surface-water gley. Northern section of the route is underlain by Ironpan soils, surface water-gleys and brown-earths.
Soilscape data (1:250k scale) identifies the majority of the route underlain by "Very acid loamy upland soils with a wet peaty surface". Stretches of the route in the vicinity of Bryn y Gors-goch area to the Afon Brenig and from the Nant y Fuddai area to the northern end of the route are underlain by "Slowly permeable wet very acid upland soils with a peaty surface".
A small section of the route at the southern edge and within the Afon Fechan catchment is underlain by "Blanket bog peat soils".
No geological features of interest were noted on the 1:50k BGS superficial geology mapping. Areas of mapped peat align with information presented in above soils information. Majority of route underlain by Glacial Till with riparian corridors underlain by fluvial deposits. Alwen Forest Grid Route Options Matrix (see notes below) North 2 Route length (km) 8.17 Narrative H M L
Hydrology Majority of route is located within the River Dee River Basin District. Northern section of route located within the Western Wales River Basin District.
Majority of cable route is located within the catchment of Llyn Brenig with route to the north within the catchment of Afon Ystrad and Afon Concwest. A small section of the route at its start in the south is located within the catchment of Alwen Reservoir.
Overall WFD 2018 (interim) catchment classification for Afon Brenig, Afon Alwen (above Afon Brenig) and Llyn Brenig is Moderate. Overall WFD 2018 (interim classification for catchment of Afon Ystrad is Good.
Llyn Brenig and catchment of Afon Alwen are designated Drinking Water Protected Areas.
11 watercourse crossings identified.
Flood risk - no significant risk of fluvial flooding. 1 crossing over the Afon Brenig within Flood Zone 3 (greater than 1 in 30 chance of flooding in each year).
Private water supplies - a number of properties identified beyond the 140 m buffer that could be connected to private water supply.
Slope analysis Slope less than 8⁰ over whole route apart from a 0.5 km section at the eastern end of the route which is >12 ⁰
Cumulative considerations Risk to receptors will be dependent upon final construction method (OHL/underground cable).Cumulative effects may include increased risk to hydrological receptors and loss of peatland habitat. Construction activities increasing risk of pollutants entering drainage network and increased risk of flooding as well as potential to affect private and public water supply assets.
Alternative solution?* Cable route crossing over the Afon Fechan is in close proximity to Llyn Brenig. Consider realigning to increase distance from reservoir. Discount? - provide reasoning No Cultural Heritage SAMs Corridor passes between Gorsedd Bran Round Barrows to NW and Bwlch-du Round Barrow to SE, the setting of these monuments may be affected
Listed buildings Corridor includes Bwlch-du Grade II Listed Building potential for impacts on this building and its setting
Non-designated heritage assets Corridor includes Maen Llwyd standing stone, Bwlch Du boundary stone, cairns and stone setting at Tir Mostyn and a possible barrow and a structure near the eastern end. Also includes records of environmental deposits and "turbury" (peat cutting) - the former relating to the river channel (and likely to be extensive and varying across much of the study area), the latter more localised (to within at most a few fields). Potential for direct impacts on these known assets and on possible un-recorded assets, potential for the setting of the upstanding assets to be affected.
Conservation areas None Historic landscapes Within Denbigh Moors Landscape of Special Historic Interest - registered for its interest as an extensive area of managed heather moorland (early 20th century grouse shooting), but including groups of prehistoric monuments on hill summits and the archaeological trail around Brenig reservoir created by relocating heritage assets from the flooded area. ASIDOHL assessment will be required.
Cumulative considerations Potential for cumulative impacts on prehistoric monuments' settings through in combination effects with Alwen and other windfarms
Alternative solution?* Cabling along sections of the B4501 would avoid impacting on setting of the barrows and the listed building
Discount? - provide reasoning Noise Identification of noise receptors Assuming the whole route is overhead one NSR would be required to be considered within an operational noise assessment and a further three NSRs that are just on the edge of our study area buffer and should probably be included for completeness.
Cumulative considerations No cumulative impacts are anticipated. Construction noise considerations For overground construction activities a number of properties to the north of the corridor will be required to be assessed, however, construction noise impacts are unlikely to be significant. Significant impacts may, however occur at one property to the south of the corridor at 298720, 358389, though these would be short term impacts only and unlikely to be a material planning consideration. Assuming the proposed Wind Farm Construction Compounds are used it would be advisable to restrict access for material deliveries so that the route south from the A543 only is used. This would stop HGVs from passing by close to dwellings.
Alternative solution?* Consideration should be given to realigning the route to move it further to the north away from the receptor at 298720, 358389 Alternatively, undergrounding near this receptor would remove any potential operational noise impacts.
Discount? - provide reasoning Socio-economic Tourism/socio-economic receptors Gors Maen Llwyd Nature reserve. Sportsman's Arms.
Public rights of way, National Trails and open access Runs along edge of Historic Landscape area. Open Access Countryside to the south. 4.7km of route crosses Denbigh Moors Registered Historic Landscape . Adjacent to the Brenig and Two Lakes trails.
Common land None within route. Cumulative considerations Cumulative interaction with Clocaenog, Tir Mostyn and Brenig wind farms all seen from the trails in the vicinity. Also cumulative interaction with consented Pant y Maen Wind Farm. Alternative solution?*
Discount? - provide reasoning
Note This matrix is for the consideration of the impacts of overhead lines on each route
H M L High, medium or low risk/impact
* Alternative solution - Please include alternative solutions that you think might be appropriate for further investigation, such as alternative location or use of underground cabling rather than overhead. Alwen Forest Grid Route Options Matrix (see notes below) South 1 Route length (km) 10.4 Narrative H M L
Landscape Landscape designations inc LANDMAP Cultural Landscape M 5.5km of route crosses ‘Conwy Uplands’ (Evaluation: High) 4.7km of route crosses ‘Clocaenog Forest’ (Evaluation: High) Historic Landscape 4.7km of route crosses ‘Foel Goch’ (Evaluation: High) 4.1km of route crosses ‘Clocaenog Forest’ (Evaluation: High) 1km of route crosses ‘Alwen & Brenig’ (Evaluation: High) Landscape Habitat 4.7km of route crosses ‘Clocaenog Conifer Forest’ (Evaluation: High) 3.6km of route crosses ‘Clocaenog Forest’ (Evaluation: High) 1.6km of route crosses ‘Llyn Brenig Upland Heath’ (Evaluation: Outstanding) Visual and Sensory 0.6km of route crosses ‘Alwen valley’ (Evaluation: High)
Landscape & visual considerations • The majority of the route follows tracks within Clocaenog Forest, where trees provide visual enclosure. The clearance necessary to accommodate the route has partially occurred when corridors for the tracks were created. If additional felling is required, it is considered a limited adverse landscape and visual impact would arise, given that the activities associated with forestry results in a working landscape character that is dynamic and undergoing constant change. The level of enclosure will vary as trees are felled and new ones grow. • The route’s alignment is to the east of a ridgeline that is occupied by the Tir Mostyn wind farm, ensuring that views towards the route from areas in the west, are obscured by intervening landform and forest, as well as being seen in context of adjacent wind turbines providing vertical elements within the landscape. • Along its southern section, the route crosses the mid-slopes of the Afon Brenig valley to the south of Llyn Brenig, where there is a strong sense of rural character, given the distinctive rolling landform, woodland copses/tree groups and stone wall field pattern which are characteristic of the Denbigh Moors National Landscape Character Area (NLCA). Although it would be well enclosed and backclothed by the surrounding rolling landform, the route would form visual detractors within the rural landscape. • Within the proposed Alwen Forest Wind Farm, the route connects to the proposed southern substation. It is located within an area of forest where trees provide visual enclosure, and limit potential views towards it.
Other landscape considerations None
Cumulative considerations The route is in proximity to the existing Tir Mostyn wind farm as well as the Clocaenog wind farm which is currently undergoing construction. The route would provide additional vertical features within the landscape; however as the wind turbines are much larger and visible from a greater extent, the route would not result in cumulative issues with the surrounding wind farms.
Existing overhead lines mounted on wooden poles run along the bottom of the Afon Brenig valley providing some disturbance to its rural character. The additional route would intensify the disturbance and result in the crossing of overhead lines.
Alternative solution?* It is not necessary to underground the route where it runs through areas of forest as visibility is limited and could result in additional felling.
It is considered that more careful routeing should occur when crossing the Afon Brenig valley, with particular regard to the sensitive rolling landform.
Discount? - provide reasoning No, although the section crossing the Afon Brenig valley will need to be re-examined.
Ecology Designations No L
Desk study records Dormouse have been confirmed as present in Clocaenog. Goshawk and crossbill may breed in areas of mature plantation. Otter and water vole may be present in streams, surveys may be required if culverting works proposed. Nightjar breed on most clear fell areas in Clocaenog. Open areas beyond the plantation are likely to be grazed pasture. However, ground nesting birds may still be a consideration.
Survey findings Bird survey work has identified regular herring gull, lesser black-backed gull and common gull flights into and out of Llyn Brenig over the dam. However, flights are tyically higher than the proposed pole height.
Cumulative considerations Removal of trees at Clocaenog may give rise to cumulative effects on dormouse, red squirrel, goshawk and nightjar.
Alternative solution?* Discount? - provide reasoning No
Hydrology/Geology/Topography Peat/geology Limited soil information available for the National Forest Estate. Data that is available shows that route does not cross significant areas of bog. The route skirts a small area of basin bog at SH 986 534.
Soilscape data (1:250k scale) identifies the soils underlying the route vary from "Very acid loamy upland soils with a wet peaty surfac e" and "Slowly permeable wet very acid upland soils with a peaty surface ". No areas of blanket bog peat soils are mapped along this route.
No geological features of interest were noted on the 1:50k BGS superficial geology mapping. Small sporadic areas of peat mapped along route with largest area located at start of route to the south. Majority of route underlain by Glacial Till with riparian corridors underlain by fluvial deposits. Alwen Forest Grid Route Options Matrix (see notes below) South 1 Route length (km) 10.4 Narrative H M L
Hydrology Majority of route is located within the River Dee River Basin District. Northern section of route located within the Western Wales River Basin District.
Cable route is located within the catchments of Afon Brenig (downstream of Llyn Brenig reservoir), Afon Corris, Afon Clywedog and Afon Concwest.
Overall WFD 2018 (interim) catchment classification for Afon Alwen, Afon Corris and Afon Concwest is Moderate.
Afon Alwen is a designated Drinking Water Protected Area.
11 watercourse crossings identified.
Flood risk - no significant risk of fluvial flooding along majority of route. One area within catchment of Afon Brenig, downstream of Llyn Brenig, located in Flood Zone 3 (greater than 1 in 30 chance of flooding in each year).
Private water supplies - a number of properties identified beyond the 140 m buffer that could be connected to private water supply.
Slope analysis Generally the route is less than 8⁰ with a couple of very short sections (50 to 200m length) in the 8⁰ to 10⁰ range.
Cumulative considerations Risk to receptors will be dependent upon final construction method (OHL/underground cable).Cumulative effects may include increased risk to hydrological receptors and loss of peatland habitat. Construction activities increasing risk of pollutants entering drainage network and increased risk of flooding as well as potential to affect private and public water supply assets. Alternative solution?* No Discount? - provide reasoning No Cultural Heritage SAMs The corridor includes Hafoty Wen Ring Cairn and Twyr y Hill Round Barrow - there is a risk of direct impacts to these monuments and also potential for their setting to be affected
Listed buildings Corridor passes north of Pont-y-rhuddfa Grade II Listed Building - potential for its setting to be affected
Non-designated heritage assets Corridor includes group of historic buildings at Elorgarreg, Swch Isgaer Wen earthwork, a trig point, Hafoty Wen Enclosure and Ring Cairn, Hafoty Well and Spring, Swch Gaerwen boundary stone, Marian Gwyn Well, Meifod Boundary Stone, Fynnon Terfyn spring, Marian Gwyn boundary stones. Potential for direct impacts on these known assets and on possible un-recorded assets, potential for the setting of the upstanding assets to be affected.
Conservation areas None Historic landscapes Will be visible from parts of Denbigh Moors Landscape of Special Historic Interest (depending on landform and felling) - registered for its interest as an extensive area of managed heather moorland (early 20th century grouse shooting), but including groups of prehistoric monuments on hill summits (most likely areas to have visibility) and the archaeological trail around Brenig reservoir created by relocating heritage assets from the flooded area. ASIDOHL assessment will be required.
Cumulative considerations Potential for cumulative impacts on prehistoric monuments' settings through in combination effects with Alwen and other windfarms
Alternative solution?* A short section of underground cable between platforms SAMs and non-designated standing stone and cairns could avoid setting issues - but may increase risk of currently unknown buried archaeology being impacted Discount? - provide reasoning Noise Identification of noise receptors Assuming the whole route is overhead six NSRs identified that would be required to be considered within an operational noise assessment and a further one NSRs that is just on the edge of our study area buffer and should probably be included for completeness. However, please note that one NSR is the Static Caravan park, so this effectively counts as multiple receptors. Google Earth image appears to show 21 separate caravans.
Cumulative considerations No cumulative impacts are anticipated with regards to operational noise. Where construction of the wind farm occurs at the same time as the grid route construction, cumulative impacts may occur from the use of the proposed 'alternative' construction compound.
Construction noise considerations For overhead construction activities a number of properties within the southern section of the route will be required to be assessed and some short term significant impacts may, occur. Assessment of construction impacts on properties close to the substation connection point at the northern end of the route will also be required. If undergrounding of the cable is likely to occur in the southern section of the route then it will be important to consider whether any Horizontal Directional Drilling (HDD) may be required, for example to cross roads such as the B4501, or watercourses such as Afon Brenig. This could introduce significantly more noise sources and increase duration of exposure to noise than overhead construction activities.
Alternative solution?* No alternative solutions proposed other than maximising distance between cable route and identified receptors. Best practice construction techniques and noise control can be employed to reduce any construction impacts.
Discount? - provide reasoning Socio-economic Tourism/socio-economic receptors Views from the route around Llyn Brenig, especially whilst walking/cycling over the dam. Pentre Llyn Cymmer Outdoor Education Centre located over 1 km S and forestry and topography likely to minimise any visibility.
Public rights of way, National Trails and open access The majority of the route follows tracks within Clocaenog Forest. Crosses the Clwydian Way. Adjacent to Brenig and Two Lakes trails. Open access countryside to the south.
Common land None within route. Cumulative considerations Cumulative interaction with Clocaenog and Tir Mostyn wind farms where route runs directly adjacent to them.
Alternative solution?*
Discount? - provide reasoning
Note This matrix is for the consideration of the impacts of overhead lines on each route
H M L High, medium or low risk/impact
* Alternative solution - Please include alternative solutions that you think might be appropriate for further investigation, such as alternative location or use of underground cabling rather than overhead. Alwen Forest Grid Route Options Matrix (see notes below) South 2 Route length (km) 8.57 Narrative H M L
Landscape Landscape designations inc LANDMAP Cultural Landscape H 3km of route crosses ‘Conwy Uplands’ (Evaluation: High) 1.6km of route crosses ‘Denbigh Moors’ (Evaluation: High) 3.4km of route crosses ‘Clocaenog Forest’ (Evaluation: High) Historic Landscape 5.1km of route crosses ‘Foel Goch’ (Evaluation: High) 2km of route crosses ‘Clocaenog Forest’ (Evaluation: High) 1km of route crosses ‘Alwen & Brenig’ (Evaluation: High) Landscape Habitat 1.6km of route crosses ‘Llyn Brenig Upland Heath’ (Evaluation: Outstanding) 3.4km of route crosses ‘Clocaenog Conifer Forest’ (Evaluation: High) 1.2km of route crosses ‘Clocaenog forest’ (Evaluation: High) Visual and Sensory 0.6km of route crosses ‘Alwen valley’ (Evaluation: High)
Landscape & visual considerations • Approximately 1.6km of the route crosses moorland comprising a relatively remote and open character that is particularly valued for its heathland habitat. The area of moorland lacks any vertical features although the route is in proximity to Tir Mostyn wind farm. It is designated open access land with a bridleway crossing centrally. Given its elevated nature, users of the bridleway are afforded uninterrupted panoramic views that look across Llyn Brenig, which would be interrupted by the overhead line. • The route partly follows the Clwydian Way long-distance route where it runs within Clocaenog Forest. • When looking towards the route from sensitive viewing locations around the northern and western flanks of Llyn Brenig (including the Llyn Brenig visitor centre), the steep hillside occupied by Clocaenog Forest provides a backdrop to the majority of the route, resulting in limited perceptibility, as well as being partly obscured in places by groups of trees associated with the forest. • The route runs along the southern edge of Llyn Brenig and along the top of the reservoir dam resulting in it being exposed and visible when viewed from sensitive locations to the north, e.g. users of the Clwydian Way long-distance route and the Archaeological Trail, as well as those visiting the Llyn Brenig visitor centre, where panoramic views are afforded that look across the reservoir towards its southern edge, and from lower elevations to the south where the wooden poles would be seen on the skyline. The route would add an element of discord within views that are relatively simplistic comprising hills that surround water. • The route also runs along the south eastern edge of Llyn Brenig resulting in visibility when viewed from the opposite side of the reservoir (i.e. from the north and west), although the route would be seen against Clocaenog Forest. • Within the proposed Alwen Forest Wind Farm, the route connects to the southern substation. It is located within an area of forest where trees provide visual enclosure, and limit potential views towards it. Other landscape considerations 4.9km of route crosses Denbigh Moors Registered Historic Landscape.
Cumulative considerations The route is in proximity to the existing Tir Mostyn wind farm as well as the Clocaenog wind farm which is currently undergoing construction. The route would provide additional vertical features within the landscape; however as the wind turbines are much larger and visible from a greater extent, the route would not result in cumulative issues with the surrounding wind farms.
Alternative solution?* It is considered that undergrounding of the route could be an option to minimise adverse visual effects. However there will be some visual scarring across the moorland as a result of the small extent of earthworks required to accommodate underground cables, as well as disturbing its associated heathland habitat.
As the section of the route that runs along the southern edge of Llyn Brenig would be sensitive from a visual perspective, an option would be to underground this part of the route, although it is recognised that this may not be possible under the dam wall. Discount? - provide reasoning Yes. There will be an adverse impact on the character of the moorland which is a sensitive landscape, and an adverse visual impact due to the prominent position of the southern section which will be visible from sensitive viewing locations to the north. Ecology Designations None L
Desk study records Dormouse have been confirmed as present in Clocaenog. Goshawk and crossbill may breed in areas of mature plantation. Otter and water vole may be present in streams, surveys may be required if culverting works proposed. Nightjar breed on most clear fell areas in Clocaenog. Open areas beyond the plantation are likely to be grazed pasture. However, ground nesting birds may still be a consideration.
Survey findings Bird survey work has identified regular herring gull, lesser black-backed gull and common gull flights from and to Llyn Brenig over the dam. However, flights are tyically higher than the proposed pole height.
Cumulative considerations Removal of trees at Clocaenog may give rise to cumulative effects on dormouse, red squirrel, goshawk and nightjar.
Alternative solution?* Discount? - provide reasoning No
Hydrology/Geology/Topography Peat/geology Limited soil information available for the National Forest Estate. Data that is available shows that route does not cross significant areas of bog.
Soilscape data (1:250k scale) identifies the soils underlying the route vary from "Very acid loamy upland soils with a wet peaty surface" and "Slowly permeable wet very acid upland soils with a peaty surface". No areas of blanket bog peat soils are mapped along this route.
No geological features of interest were noted on the 1:50k BGS superficial geology mapping. Small sporadic areas of peat mapped along route with largest area located at start of route to the south. Majority of route underlain by Glacial Till with riparian corridors underlain by fluvial deposits. Alwen Forest Grid Route Options Matrix (see notes below) South 2 Route length (km) 8.57 Narrative H M L
Hydrology Majority of route is located within the River Dee River Basin District. Northern section of route located within the Western Wales River Basin District.
Cable route is located within the catchments of Afon Brenig (downstream of Llyn Brenig reservoir), Aber Berbo, Aber llech-Daniel, Afon Clywedog and Afon Concwest.
Overall WFD 2018 (interim) catchment classification for Afon Alwen, Afon Brenig, Afon and Afon Concwest is Moderate.
Afon Alwen is a designated Drinking Water Protected Area.
9 watercourse crossings identified.
Flood risk - no significant risk of fluvial flooding along majority of route. One area within catchment of Afon Brenig, at outfall of Llyn Brenig located in Flood Zone 3 (greater than 1 in 30 chance of flooding in each year).
Private water supplies - a number of properties identified beyond the 140 m buffer that could be connected to private water supply.
Slope analysis Most of the route is below 8⁰ other than, 1 km section just south of the SSSI and a 1 km section in front of the dam. Approximately 300m at the approach to the proposed southern substation is in the greater than 8 ⁰. Cumulative considerations Risk to receptors will be dependent upon final construction method (OHL/underground cable). Cumulative effects may include increased risk to hydrological receptors. Construction activities increasing risk of pollutants entering drainage network and increased risk of flooding as well as potential to affect private and public water supply assets. Alternative solution?* No Discount? - provide reasoning No Cultural Heritage SAMs Corridor includes Hafoty Wen Ring Cairn and Twyr y Hill Round Barrow and passes southeast of circular platforms at Hen Ddinbych - potential for direct impacts to cairn and barrow and potential for the setting of all three monuments to be affected.
Listed buildings None
Non-designated heritage assets Corridor runs along Llyn Brenig Reservoir Dam, includes boundary stone and Aber Berbo standing stone and Bryn Maen-Cleddau standing stone and Aber Llech Daniel Kerbed Cairn, Brenig Cairn and pre-barrow timber building and Marian Gwyn boundary stones. Potential for direct impacts on these known assets and on possible un-recorded assets, potential for the setting of the upstanding assets to be affected, in particular the non designated cairns and standing stone which may be ssociated with the Scheduled Hen Ddinbych platforms. Conservation areas None Historic landscapes Within Denbigh Moors Landscape of Special Historic Interest - registered for its interest as an extensive area of managed heather moorland (early 20th century grouse shooting), but including groups of prehistoric monuments on hill summits and the archaeological trail around Brenig reservoir created by relocating heritage assets from the flooded area. ASIDOHL assessment will be required.
Cumulative considerations Potential for cumulative impacts on prehistoric monuments' settings through in combination effects with Alwen and other windfarms
Alternative solution?* A short section of underground cable between platforms SAMs and non-designated standing stone and cairns could avoid setting issues - but may increase risk of currently unknown buried archaeology being impacted Discount? - provide reasoning Noise Identification of noise receptors Assuming the whole route is overhead two NSRs identified that would be required to be considered within an operational noise assessment.
Cumulative considerations No cumulative impacts are anticipated with regards to operational noise. Where construction of the wind farm occurs at the same time as the grid route construction, cumulative impacts may occur from the use of the proposed 'alternative' construction compound.
Construction noise considerations For overhead construction activities a number of properties within the southern section of the route will be required to be assessed though some short term significant impacts are only anticipated at one location (296653, 353935). Assessment of construction impacts on properties close to the substation connection point at the northern end of the route will also be required. If undergrounding of the cable is likely to occur in the southern section of the route then it will be important to consider whether any Horizontal Directional Drilling (HDD) may be required, for example to cross roads such as the B4501, or watercourses such as Afon Brenig. This could introduce significantly more noise sources and increase duration of exposure to noise than overhead construction activities.
Alternative solution?* No alternative solutions proposed other than maximising distance between cable route and identified receptors. Best practice construction techniques and noise control can be employed to reduce any construction impacts.
Discount? - provide reasoning Socio-economic Tourism/socio-economic receptors Visible from Brenig Visitor Centre. Runs adjacent to Brenig dam entrance and Memorial Stone. Pentre Llyn Cymmer Outdoor Education Centre located over 1 km S and forestry and topography likely to minimise any visibility.
Public rights of way, National Trails and open access Runs adjacent to Clwydian Way path 1 km. Designated open access land with a bridleway crossing centrally. Adjacent to Brenig and Two Lakes trails. Brenig Archaeological Trail is about 1 km to the west of this route. Open access countryside to the south Common land None within route. Cumulative considerations Cumulative interaction with Clocaenog, Tir Mostyn and Brenig wind farms all seen from the trails in the vicinity and visitor centre.
Alternative solution?* Underground section that runs along the dam as this would be very intrusive to visitors cycling, walking, sailing, fishing at Brenig Lake. Route also part of Clwydian Way. Discount? - provide reasoning
Note This matrix is for the consideration of the impacts of overhead lines on each route
H M L High, medium or low risk/impact
* Alternative solution - Please include alternative solutions that you think might be appropriate for further investigation, such as alternative location or use of underground cabling rather than overhead. Alwen Forest Grid Route Options Matrix (see notes below) South 3 Route length (km) 8.48 Narrative H M L
Landscape Landscape designations inc LANDMAP Cultural Landscape M-H 3km of route crosses ‘Conwy Uplands’ (Evaluation: High) 1.6km of route crosses ‘Denbigh Moors’ (Evaluation: High) 3.4km of route crosses ‘Clocaenog Forest’ (Evaluation: High) Historic Landscape 5.1km of route crosses ‘Foel Goch’ (Evaluation: High) 2km of route crosses ‘Clocaenog Forest’ (Evaluation: High) 1km of route crosses ‘Alwen & Brenig’ (Evaluation: High) Landscape Habitat 1.6km of route crosses ‘Llyn Brenig Upland Heath’ (Evaluation: Outstanding) 3.4km of route crosses ‘Clocaenog Conifer Forest’ (Evaluation: High) 1.2km of route crosses ‘Clocaenog forest’ (Evaluation: High) Visual and Sensory 0.6km of route crosses ‘Alwen valley’ (Evaluation: High)
Landscape & visual considerations This route follows the same alignment as South 2 apart from the southern section differing as follows:
• The route crosses the mid-slopes of the Afon Brenig valley to the south of Llyn Brenig, where there is a strong sense of rural character, given the distinctive rolling landform, woodland copses/tree groups and stone wall field pattern which are characteristic of the Denbigh Moors NLCA. Although well enclosed and backclothed by the rolling landform, the route would form visual detractors.
Other landscape considerations 3.3km of route crosses Denbigh Moors Registered Historic Landscape.
Cumulative considerations The route is in proximity to the existing Tir Mostyn wind farm as well as the Clocaenog wind farm which is currently undergoing construction. The route would provide additional vertical features within the landscape; however as the wind turbines are much larger and visible from a greater extent, the route would not result in cumulative issues with the surrounding wind farms.
Existing overhead lines mounted on wooden poles run along the bottom of the Afon Brenig valley providing some disturbance to its rural character. The Alternative solution?* It is considered that undergrounding of the route could be an option where it crosses open moorland to minimise adverse visual effects. However there will be some visual scarring across the moorland as a result of the small extent of earthworks required to accommodate underground cables, as well as disturbing the associated heathland habitat.
There will be some visual prominence where the route runs along the south-eastern edge of Llyn Brenig. This section could be undergrounded or moved further to the east where it would run along a forestry track and be visually enclosed, although felling may be required to provide the appropriate Discount? - provide reasoning Yes.clearance There corridor. will be an adverse impact on the character of the open moorland which is a sensitive landscape, and adverse visual impact on sensitive views from the bridleway and Clwydian Way long-distance route. Ecology Designations None L
Desk study records Dormouse have been confirmed as present in Clocaenog. Goshawk and crossbill may breed in areas of mature plantation. Otter and water vole may be present in streams, surveys may be required if culverting works proposed. Nightjar breed on most clear fell areas in Clocaenog. Open areas beyond the plantation are likely to be grazed pasture. However, ground nesting birds may still be a consideration.
Survey findings Bird survey work has identified regular herring gull, lesser black-backed gull and common gull flights from and to Llyn Brenig over the dam. However, flights are tyically higher than the proposed pole height.
Cumulative considerations Removal of trees at Clocaenog may give rise to cumulative effects on dormouse, red squirrel, goshawk and nightjar.
Alternative solution?* Discount? - provide reasoning No
Hydrology/Geology/Topography Peat/geology Cable other than adjustment at Llyn Brenig reservoir follows same route as the South 2.
Limited soil information available for the National Forest Estate. Data that is available shows that route does not cross significant areas of bog.
Soilscape data (1:250k scale) identifies the soils underlying the route vary from "Very acid loamy upland soils with a wet peaty surface" and "Slowly permeable wet very acid upland soils with a peaty surface". No areas of blanket bog peat soils are mapped along this route.
No geological features of interest were noted on the 1:50k BGS superficial geology mapping. Small sporadic areas of peat mapped along route with largest area located at start of route to the south. Majority of route underlain by Glacial Till with riparian corridors underlain by fluvial deposits. Alwen Forest Grid Route Options Matrix (see notes below) South 3 Route length (km) 8.48 Narrative H M L
Hydrology Majority of route is located within the River Dee River Basin District. Northern section of route located within the Western Wales River Basin District.
Cable route is located within the catchments of Afon Brenig (downstream of Llyn Brenig reservoir), Aber Berbo, Aber llech-Daniel, Afon Clywedog and Afon Concwest.
Overall WFD 2018 (interim) catchment classification for Afon Alwen, Afon Brenig, Afon and Afon Concwest is Moderate.
Afon Alwen is a designated Drinking Water Protected Area.
9 watercourse crossings identified.
Flood risk - no significant risk of fluvial flooding along majority of route. One area within catchment of Afon Brenig, at outfall of Llyn Brenig located in Flood Zone 3 (greater than 1 in 30 chance of flooding in each year).
Private water supplies - a number of properties located within southern section of route identified beyond the 140 m buffer that could be connected to private water supply.
Slope analysis Approximately 2km of the route is between 8⁰ to 10⁰ range.
Cumulative considerations Risk to receptors will be dependent upon final construction method (OHL/underground cable).Cumulative effects may include increased risk to hydrological receptors. Construction activities increasing risk of pollutants entering drainage network and increased risk of flooding as well as potential to affect private and public water supply assets. Alternative solution?* No Discount? - provide reasoning No Cultural Heritage SAMs Corridor includes Hafoty Wen Ring Cairn (very close to route) and Twyr y Hill Round Barrow and passes south-east of circular platforms at Hen Ddinbych - potential for direct impacts to cairn and barrow if not microsited to avoid; potential setting impacts on circular platforms if OHL here
Listed buildings Corridor passes north of Pont-y-rhuddfa Grade II Listed Building - potential for its setting to be affected
Non-designated heritage assets Corridor includes group of historic buildings at Elorgarreg Uchaf and Isaf, boundary stone, Aber Berbo standing stone, Bryn Maen-Cleddau standing stone and Aber Llech Daniel Kerbed Cairn, Brenig Cairn and pre-barrow timber building, and Marian Gwyn boundary stones. Potential for direct impacts on these known assets and on possible un-recorded assets, potential for the setting of the upstanding assets to be affected, in particular the non designated cairns and standing stone which may be ssociated with the Scheduled Hen Ddinbych platforms.
Conservation areas None Historic landscapes Within Denbigh Moors Landscape of Special Historic Interest - registered for its interest as an extensive area of managed heather moorland (early 20th century grouse shooting), but including groups of prehistoric monuments on hill summits and the archaeological trail around Brenig reservoir created by relocating heritage assets from the flooded area. ASIDOHL assessment will be required.
Cumulative considerations Potential for cumulative impacts on prehistoric monuments' settings through in combination effects with Alwen and other windfarms
Alternative solution?* A short section of underground cable between platforms SAMs and non-designated standing stone and cairns could avoid setting issues - but may increase risk of currently unknown buried archaeology being impacted Discount? - provide reasoning Proximity to Hafoty Wen unless the route can be microsited to avoid this Noise Identification of noise receptors Assuming the whole route is overhead three NSRs identified that would be required to be considered within an operational noise assessment. However, please note that one NSR is the Static Caravan park, so this effectively counts as multiple receptors. Google Earth image appears to show 21 separate caravans.
Cumulative considerations No cumulative impacts are anticipated with regards to operational noise. Where construction of the wind farm occurs at the same time as the grid route construction, cumulative impacts may occur from the use of the proposed 'alternative' construction compound.
Construction noise considerations For overhead construction activities a number of properties within the southern section of the route (including the caravan site) will be required to be assessed and some short term significant impacts may occur. Assessment of construction impacts on properties close to the substation connection point at the northern end of the route will also be required. If undergrounding of the cable is likely to occur in the southern section of the route then it will be important to consider whether any Horizontal Directional Drilling (HDD) may be required, for example to cross roads such as the B4501, or watercourses such as Afon Brenig. This could introduce significantly more noise sources and increase duration of exposure to noise than overhead construction activities.
Alternative solution?* No alternative solutions proposed other than maximising distance between cable route and identified receptors. Best practice construction techniques and noise control can be employed to reduce any construction impacts.
Discount? - provide reasoning Socio-economic Tourism/socio-economic receptors Views from the route around Llyn Brenig, especially whilst walking/cycling over the dam looking south. Route also follows the south-west shoreline, visible from Brenig Visitor Centre. Pentre Llyn Cymmer Outdoor Education Centre located over 1 km S and forestry and topography likely to minimise any visibility. The Brenig Archaeological Trail is about 1 km to the west of this route. Public rights of way, National Trails and open access Runs alongside and Clwydian Way. Adjacent to Brenig and Two Lakes trails. The Brenig Archaeological Trail is about 1 km to the west of this route.
Common land None within route. Cumulative considerations Cumulative interaction with Clocaenog, Tir Mostyn and Brenig wind farms all seen from the trails in the vicinity and visitor centre.
Alternative solution?* Underground section that runs along south-western shoreline to minimise impact on visitor centre and users of Llyn Brenig.
Discount? - provide reasoning
Note This matrix is for the consideration of the impacts of overhead lines on each route
H M L High, medium or low risk/impact
* Alternative solution - Please include alternative solutions that you think might be appropriate for further investigation, such as alternative location or use of underground cabling rather than overhead. Alwen Forest Grid Route Options Matrix (see notes below) Route A Route length (km) 10.2 Narrative H M L
Landscape Landscape designations inc LANDMAP Cultural Landscape L-M 5.5km of route crosses ‘Conwy Uplands’ (Evaluation: High) 4.7km of route crosses ‘Clocaenog Forest’ (Evaluation: High) Historic Landscape 4.7km of route crosses ‘Foel Goch’ (Evaluation: High) 4.1km of route crosses ‘Clocaenog Forest’ (Evaluation: High) 1km of route crosses ‘Alwen & Brenig’ (Evaluation: High) Landscape Habitat 4.7km of route crosses ‘Clocaenog Conifer Forest’ (Evaluation: High) 3.6km of route crosses ‘Clocaenog Forest’ (Evaluation: High) 1.6km of route crosses ‘Llyn Brenig Upland Heath’ (Evaluation: Outstanding) Visual & Sensory 0.6km of route crosses ‘Alwen valley’ (Evaluation: High) Landscape & visual considerations This route is similar in its alignment to South 1 apart from small sections that deviate in the north and the south as follows:
• In the north the route crosses a gulley which accommodates a forestry track along its edge and associated corridor that has been cleared of trees. As a result, there is intervisibility between the gulley and elevated areas to the north-east including an area of open access land at Moel Ytta. When viewed from this area, the route would partly breach the skyline as it crosses the open gulley between blocks of forest, though seen in the context of the dynamic working forest landscape. • The southern section of the route follows a public road before running through an area of forest which would result in felling to accommodate the necessary clearance corridor. Two public rights of way run north to south through the forest that the route would cross. • The route also crosses the Afon Brenig valley to the south of Llyn Brenig, although located at the foot of the slope that the reservoir wall sits on top of, and therefore being largely contained by surrounding topography, in contrast to the more exposed alignment of South 1 and 3.
Other landscape considerations 1.2km of route crosses Denbigh Moors Registered Historic Landscape.
Cumulative considerations The route is in proximity to the existing Tir Mostyn wind farm as well as the Clocaenog wind farm which is currently undergoing construction. The route would provide additional vertical features within the landscape; however as the wind turbines are much larger and visible from a greater extent, the route would not result in cumulative issues with the surrounding wind farms.
Alternative solution?* It is not necessary to underground the route where it runs through areas of forest as visibility is limited and could result in additional felling. However, as part of the section in the north is likely to result in adverse visual impact where it breaches the skyline, an option would be to underground this section as it crosses the gulley. This may result in additional felling but these works would be seen in context of the overall works that occur within Clocaenog Forest.
Discount? - provide reasoning No
Ecology Designations None, but adjacent to Mynydd Hiraethog SSSI L
Desk study records Dormouse have been confirmed as present in Clocaenog. Goshawk and crossbill may breed in areas of mature plantation. Otter and water vole may be present in streams, surveys may be required if culverting works proposed. Nightjar breed on most clear fell areas in Clocaenog. Open areas beyond the plantation are likely to be grazed pasture. However, ground nesting birds may still be a consideration.
Survey findings Black grouse confirmed present (lekking) within the SSSI. Bird survey work has identified regular herring gull, lesser black-backed gull and common gull flights from and to Llyn Brenig over the dam. However, flights are tyically higher than the proposed pole height.
Cumulative considerations Removal of trees at Clocaenog may give rise to cumulative effects on dormouse, red squirrel, goshawk and nightjar.
Alternative solution?* Discount? - provide reasoning No. However, there may be a need to demostrate that no SSSI notified habitats are affected / indirectly affected through pollution/ silting etc.
Hydrology/Geology/Topography Peat/geology Soil information available for the National Forest Estate. Data shows that route does not directly cross significant areas of bog. The route skirts two areas of Basin Bog at SH 985 534 and SJ 007 562.
Soilscape data (1:250k scale) identifies the soils underlying the route vary from "Very acid loamy upland soils with a wet peaty surface" and "Slowly permeable wet very acid upland soils with a peaty surface". No areas of blanket bog peat soils are mapped along this route.
No geological features of interest were noted on the 1:50k BGS superficial geology mapping. Small sporadic areas of peat mapped along route with largest area located at start of route to the south. Majority of route underlain by Glacial Till with riparian corridors underlain by fluvial deposits. Alwen Forest Grid Route Options Matrix (see notes below) Route A Route length (km) 10.2 Narrative H M L
Hydrology Route located within the River Dee and Western Wales River Basin Districts. Route follows existing road network.
Cable route is located within the catchments of Afon Brenig (downstream of Llyn Brenig reservoir), Afon Alwen, Afon Corris, Afon Clywedog and Afon Concwest
Overall WFD 2018 (interim) catchment classification for Afon Alwen, Afon Brenig, Afon and Afon Concwest is Moderate.
Afon Alwen is a designated Drinking Water Protected Area.
14 watercourse crossings identified.
Flood risk - no significant risk of fluvial flooding along majority of route. One area within catchment of Afon Brenig, at outfall of Llyn Brenig located in Flood Zone 3 (greater than 1 in 30 chance of flooding in each year).
Private water supplies - a number of properties located within southern section of route identified beyond the 140 m buffer that could be connected to private water supply.
Slope analysis Generally the whole route is below 8⁰ with just a couple of very short sections (50 to 500m length) between 8⁰ and 10 ⁰
Cumulative considerations Risk to receptors will be dependent upon final construction method (OHL/underground cable).Cumulative effects may include increased risk to hydrological receptors. Construction activities increasing risk of pollutants entering drainage network and increased risk of flooding as well as potential to affect private and public water supply assets. Alternative solution?* No Discount? - provide reasoning No Cultural Heritage SAMs Corridor includes Hafoty Wen Ring Cairn and passes southeast of circular platforms at Hen Ddinbych - potential for direct impacts to cairn and potential for the setting of the cairn and circular platforms to be affected
Listed buildings Corridor passes north of Pont-y-rhuddfa Grade II Listed Building - potential for its setting to be affected
Non-designated heritage assets Corridor passes foot of Llyn Brenig Dam, corridor includes Bryn Hir house, Swch Isgaer Wen earthwork, Hafoty Wen enclosure and ring cairn, a trig point in clearing in forestry, Hafoty well, Swch Gaerwen boundary stone, Marian Gwyn Well, Meifod Boundary Stone, Fynnon Terfyn Spring, Marian Gwyn boundary stones. Potential for direct impacts on these known assets and on possible un-recorded assets, potential for the setting of the upstanding assets to be affected.
Conservation areas None Historic landscapes Skirts the edge of the Denbigh Moors Landscape of Special Historic Interest - registered for its interest as an extensive area of managed heather moorland (early 20th century grouse shooting), but including groups of prehistoric monuments on hill summits and the archaeological trail around Brenig reservoir created by relocating heritage assets from the flooded area. ASIDOHL assessment will be required.
Cumulative considerations Potential for cumulative impacts on prehistoric monuments' settings through in combination effects with Alwen and other windfarms
Alternative solution?* A short section of underground cable between platforms SAMs and non-designated standing stone and cairns could avoid setting issues - but may increase risk of currently unknown buried archaeology being impacted
Discount? - provide reasoning Proximity to Hafoty Wen unless the route can be microsited to avoid this
Noise Identification of noise receptors Assuming the whole route is overhead six NSRs identified that would be required to be considered within an operational noise assessment and a further one NSRs that is just on the edge of our study area buffer and should probably be included for completeness. However, please note that one NSR is the Static Caravan park, so this effectively counts as multiple receptors. Google Earth image appears to show 21 separate caravans.
Cumulative considerations No cumulative impacts are anticipated with regards to operational noise. Where construction of the wind farm occurs at the same time as the grid route construction, cumulative impacts may occur from the use of the proposed 'alternative' construction compound.
Construction noise considerations For overhead construction activities a number of properties within the southern section of the route (including the caravan site) will be required to be assessed and some short term significant impacts may occur. Assessment of construction impacts on properties close to the substation connection point at the northern end of the route will also be required. If undergrounding of the cable is likely to occur in the southern section of the route then it will be important to consider whether any Horizontal Directional Drilling (HDD) may be required, for example to cross roads such as the B4501, or watercourses such as Afon Brenig. This could introduce significantly more noise sources and increase duration of exposure to noise than overground overhead activities.
Alternative solution?* No alternative solutions proposed other than maximising distance between cable route and identified receptors. Best practice construction techniques and noise control can be employed to reduce any construction impacts.
Discount? - provide reasoning Socio-economic Tourism/socio-economic receptors Views from the route around Llyn Brenig, especially whilst walking/cycling over the dam looking south. Pentre Llyn Cymmer Outdoor Education Centre located over 1 km S and forestry and topography likely to minimise any visibility.
Public rights of way, National Trails and open access Crosses Clwydian Way and B4501.
Common land None within route. Cumulative considerations Cumulative interaction with Clocaenog and Tir Mostyn wind farms where route runs directly adjacent to them.
Alternative solution?*
Discount? - provide reasoning
Note This matrix is for the consideration of the impacts of overhead lines on each route
H M L High, medium or low risk/impact
* Alternative solution - Please include alternative solutions that you think might be appropriate for further investigation, such as alternative location or use of underground cabling rather than overhead. Alwen Forest Grid Route Options Matrix (see notes below) Route B Route length (km) 9.67 Narrative H M L
Landscape Landscape designations inc LANDMAP Cultural Landscape M 5.1km of route crosses ‘Conwy Uplands’ (Evaluation: High) 4.7km of route crosses ‘Clocaenog Forest’ (Evaluation: High) Historic Landscape 4.7km of route crosses ‘Foel Goch’ (Evaluation: High) 3.3km of route crosses ‘Clocaenog Forest’ (Evaluation: High) 1.4km of route crosses ‘Alwen & Brenig’ (Evaluation: High) Landscape Habitat 4.7km of route crosses ‘Clocaenog Conifer Forest’ (Evaluation: High) 1.4km of route crosses ‘Llyn Brenig Upland Heath’ (Evaluation: Outstanding) Visual & Sensory 0.6km of route crosses ‘Alwen valley’ (Evaluation: High)
Landscape & visual considerations This route is similar in its alignment to Route A apart from the section that runs to the south-west towards Llyn Brenig as follows:
• The route leaves a public road and runs to the south-west through the Isgaer-wen Plantation following a forestry track where the clearance of trees has occurred to accommodate the track. The route would be visually enclosed by the surrounding plantation, although visible to users of a bridleway that the route crosses. • A small area of ancient woodland lies within the 140m buffer corridor. • As for South 2, the route runs along the south eastern edge of Llyn Brenig resulting in visibility when viewed from the opposite side of the reservoir (i.e. from the north and west), although the route would be seen against Clocaenog Forest. • As for Route A, the route crosses the Afon Brenig valley to the south of Llyn Brenig, although located at the foot of the slope that the reservoir wall sits on top of, therefore being largely contained by surrounding topography.
Other landscape considerations Ancient Woodland. 2.5km of route crosses Denbigh Moors Registered Historic Landscape. Cumulative considerations The route is in proximity to the existing Tir Mostyn wind farm as well as the Clocaenog wind farm which is currently undergoing construction. The route would provide additional vertical features within the landscape; however as the wind turbines are much larger and visible from a greater extent, the route would not result in cumulative issues with the surrounding wind farms.
Alternative solution?* It is not necessary to underground the route where it runs through areas of forest as visibility is limited and could result in additional felling. However, as part of the section in the north is likely to result in adverse visual impact where it breaches the skyline, an option would be to underground this section as it crosses the gulley. This may result in additional felling but these works would be seen in context of the overall works that occur within Clocaenog Forest.
Discount? - provide reasoning No
Ecology Designations None, but adjacent to Mynydd Hiraethog SSSI H
Desk study records Dormouse have been confirmed as present in Clocaenog. Goshawk and crossbill may breed in areas of mature plantation. Otter and water vole may be present in streams, surveys may be required if culverting works proposed. Nightjar breed on most clear fell areas in Clocaenog. Open areas beyond the plantation are likely to be grazed pasture. However, ground nesting birds may still be a consideration.
Survey findings Black grouse confirmed present (lekking) within the SSSI. Bird survey work has identified regular herring gull, lesser black-backed gull and common gull flights from and to Llyn Brenig over the dam. However, flights are tyically higher than the proposed pole height.
Cumulative considerations Removal of trees at Clocaenog may give rise to cumulative effects on dormouse, red squirrel, goshawk and nightjar.
Alternative solution?* Discount? - provide reasoning No. However, there may be a need to demostrate that no SSSI notified habitats are affected / indirectly affected through pollution/ silting etc.
Hydrology/Geology/Topography Peat/geology Soil information available for the National Forest Estate. Data shows that route does not directly cross significant areas of bog. The route skirts in area of Basin Bog at SJ 007 562.
Soilscape data (1:250k scale) identifies the soils underlying the route vary from "Very acid loamy upland soils with a wet peaty surface" and "Slowly permeable wet very acid upland soils with a peaty surface". No areas of blanket bog peat soils are mapped along this route.
No geological features of interest were noted on the 1:50k BGS superficial geology mapping. Small sporadic areas of peat mapped along route with largest area located at start of route to the south. Majority of route underlain by Glacial Till with riparian corridors underlain by fluvial deposits. Alwen Forest Grid Route Options Matrix (see notes below) Route B Route length (km) 9.67 Narrative H M L
Hydrology Route located within the River Dee and Western Wales River Basin Districts. Route follows existing road network.
Cable route is located within the catchments of Afon Brenig (downstream of Llyn Brenig reservoir), Afon Alwen, Afon Corris, Afon Clywedog and Afon Concwest
Overall WFD 2018 (interim) catchment classification for Afon Alwen, Afon Brenig, Afon and Afon Concwest is Moderate.
Afon Alwen is a designated Drinking Water Protected Area.
11 watercourse crossings identified.
Flood risk - no significant risk of fluvial flooding along majority of route. One area within catchment of Afon Brenig, at outfall of Llyn Brenig located in Flood Zone 3 (greater than 1 in 30 chance of flooding in each year).
Private water supplies - a number of properties located within southern section of route identified beyond the 140 m buffer that could be connected to private water supply. 1
Slope analysis Approximately 1.75 km of the route, to the south of the SSSI is in the 8⁰ to 10⁰ range. 300 m stretch on the approach to the proposed Alwen Substation is above 8⁰ . Cumulative considerations Risk to receptors will be dependent upon final construction method (OHL/underground cable).Cumulative effects may include increased risk to hydrological receptors. Construction activities increasing risk of pollutants entering drainage network and increased risk of flooding as well as potential to affect private and public water supply assets. Alternative solution?* No Discount? - provide reasoning No Cultural Heritage SAMs Corridor passes southeast of circular platforms at Hen Ddinbych - potential for their setting to be affected
Listed buildings Corridor passes north of Pont-y-rhuddfa Grade II Listed Building (but further away than other routes) - limited potential for its setting to be affected
Non-designated heritage assets Corridor passes foot of Llyn Brenig Dam, corridor includes Bryn Hir house, Marian Gwyn Well, Meifod Boundary Stone, Fynnon Terfyn Spring, Marian Gwyn boundary stones. Potential for direct impacts on these known assets and on possible un-recorded assets, potential for the setting of the upstanding assets to be affected.
Conservation areas None Historic landscapes Skirts the edge of the Denbigh Moors Landscape of Special Historic Interest - registered for its interest as an extensive area of managed heather moorland (early 20th century grouse shooting), but including groups of prehistoric monuments on hill summits and the archaeological trail around Brenig reservoir created by relocating heritage assets from the flooded area. ASIDOHL assessment will be required.
Cumulative considerations Potential for cumulative impacts on prehistoric monuments' settings through in combination effects with Alwen and other windfarms
Alternative solution?* A short section of underground cable between platforms SAMs and non-designated standing stone and cairns could avoid setting issues - but may increase risk of currently unknown buried archaeology being impacted
Discount? - provide reasoning
Noise Identification of noise receptors Assuming the whole route is overhead four NSRs identified that would be required to be considered within an operational noise assessment. The Static Caravan park is relatively close to study area buffer and if the route moved any further south this would also be required to be included within any operational noise assessment.
Cumulative considerations No cumulative impacts are anticipated with regards to operational noise. Where construction of the wind farm occurs at the same time as the grid route construction, cumulative impacts may occur from the use of the proposed 'alternative' construction compound.
Construction noise considerations For overhead construction activities a number of properties within the southern section of the route (including the caravan site) will be required to be assessed and some short term significant impacts may occur. Assessment of construction impacts on properties close to the substation connection point at the northern end of the route will also be required. If undergrounding of the cable is likely to occur in the southern section of the route then it will be important to consider whether any Horizontal Directional Drilling (HDD) may be required, for example to cross roads such as the B4501, or watercourses such as Afon Brenig. This could introduce significantly more noise sources and increase duration of exposure to noise than overhead construction activities.
Alternative solution?* No alternative solutions proposed other than maximising distance between cable route and identified receptors. Best practice construction techniques and noise control can be employed to reduce any construction impacts.
Discount? - provide reasoning Socio-economic Tourism/socio-economic receptors Views from the route around Llyn Brenig, especially whilst walking/cycling over the dam looking south. Route also follows the south-west shoreline, visible from Brenig Visitor Centre. Pentre Llyn Cymmer Outdoor Education Centre located over 1 km S and forestry and topography likely to minimise any visibility. Public rights of way, National Trails and open access Runs adjacent to Clwydian Way path 1 km and crosses B4501. Adjacent to Brenig and Two Lakes trails.
Common land None within route. Cumulative considerations Cumulative interaction with Clocaenog, Tir Mostyn and Brenig wind farms all seen from the trails in the vicinity and visitor centre.
Alternative solution?* Underground section that runs along south-western shoreline to minimise impact on visitor centre and users of Llyn Brenig.
Discount? - provide reasoning
Note This matrix is for the consideration of the impacts of overhead lines on each route
H M L High, medium or low risk/impact
* Alternative solution - Please include alternative solutions that you think might be appropriate for further investigation, such as alternative location or use of underground cabling rather than overhead.
Figures Figure 2.1: Grid Regional Context
Figure 2.2: Preliminary Site Layout
Figure 2.3: Alwen Forest Wind Farm: Grid connection routes
Figure 2.4: Alwen Forest Wind Farm: Grid Corridors.
Figure 4.1: General Arrangement Single Pole Double Crossarm Intermediate or Pin Angle
Figure 9.1: Survey Area Overview
Figure 9.2: Phase 1 Habitat Survey Results (Area A)
Figure 9.3: Phase 1 Habitat Survey Results (Area B)
Figure 9.4.: Phase 1 Habitat Survey Results (Area C)
Figure 9.5.: Phase 1 Habitat Survey Results (Area D)
Figure 9.6.: Phase 1 Habitat Survey Results (Area E)
Figure 9.7: Phase 1 Habitat Survey Results (Area F)
Figure 11.1 ZTV of the Overhead Power Line and Poles within 4 km
Figure 11.2: CZTV of the Proposed Wind Farm Turbines, Overhead Power Line and Poles
Figure 13.1: Heritage assets within the grid corridors
Figure 13.2: Heritage assts within the study area
Alwen Forest Wind Farm Grid Connection 66
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Project: Rhyl Flats Alwen Forest Wind Farm and Grid Connection,
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8 Title: 3 Figure 2.1: Grid Regional Context Key Wind farm site Area of Outstanding boundary Natural Beauty (1) Penoros Indicative grid corridor Historic Landscape 1 Area (2) Indicative grid corridor Plantation on Ancient 2 Woodlands Site (1) Indicative Southern Hendre Llwyn y Maen )" RAMSAR (1) substation National Nature Gwaenynog Bach )" SPEN Clocaenog Reserve (1) Penglogor substation Special Area of ×Ö Listed building (2) Conservation (1) Historic landscape (2) Special Protection Area (1) Scheduled monument Moel Maelogen (2) Heritage Coast (1)
0 Tyn y Ffynnon 0 Wern Uchaf Gas or oil pipeline (5) SSSI (1) 0 Moel Maelogen II 0 Meifod 6 Pant y Maen Local Nature Reserve
3 Hafodty Ddu Long distance footpath )" (1) Tir Mostyn National Cycle Cerrig Oerion Caerhafod Isaf Network (6) Country Park (1) Cae Gwyn Cerrig Oerion Brenig } } Electricity power line Parks & Gardens (2) Cil Llwyn Pool Park Farm RSPB Important Parks & Gardens Cae'r Weirglodd (Essential Setting) (2) )" Bird Area (4) Fron Bella RSPB reserve (4) National Park (1) Fron Isaf Pentre Draw Maestyddyn Isa Tan 8 Strategic Wind turbine status Cwrt y Llyn Clocaenog Forest Land at Cilgoed Search Area (3) ! Tain Y Foel Approved/Operational Ty Ucha Llyn Registered Common ! Submitted/Appeal Cefnhirfynydd Isa Land (1) Ty Isa Derwydd Bach Refused/ Withdrawn/ Maes Truan World Heritage Site (2) ! Cwm Pennaner Not Progressed Wern Ddu World Heritage Site Bryn Ffynnon Farm Nant Bach Maesgwyn Ucha (Essential Setting) (2) Hafoty Ucha Disgarth Ucha Ty Gwyn Hafoty Ucha repowering Tyn y Celyn
Aeddren Uchaf Source data reproduced with the permission of: (1) NRW (2) Cadw (3) Welsh Government (4) RSPB (5) NGET (6) Sustrans Scale @ A3: 1:250,000 Coordinate System: British National Grid 0 Braich Ddu © Crown Copyright 2019. All rights reserved. Ordnance Survey 0
0 Licence 0100031673. Contains public sector information licensed 0 under the Open Government Licence v3.0. 4 3 0 2.5 5 10 km ¯
Date: 28-10-19 Prepared by: AB Checked by: FE
Ref: GB201331_M_015_C
Drawing by: The Natural Power Consultants Limited Harbour House, Y Lanfa, Aberystwyth, SY23 1AS, UK Tel: 01970 636869 Email: [email protected] www.naturalpower.com
Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Central Avenue Baglan Energy Park Port Talbot SA12 7AX
Notes: a) Information on this plan is directly reproduced from digital and other material from different sources. Minor discrepancies may therefore occur. Where further clarification is considered necessary, this is noted through the use of text boxes on the map itself. b) For the avoidance of doubt and unless otherwise stated: 1. this plan should be used for identification purposes only, unless specifically stated above or in accompanying documentation. 2. The Natural Power Consultants Limited accepts no responsibility for the accuracy of data supplied by third parties. 3. The Natural Power Consultants Limited accepts no liability for any use which is made of this plan by a party other than its client. No third party who gains access to this plan shall have any claim against The Natural Power Consultants Limited in respect of its contents.
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Project: Alwen Forest Wind Farm, Conwy/Denbighshire Title: Figure 2.3: Alwen Forest Wind Farm: Grid Connection Routes
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5 )" Alwen Proposed Northern Substation 3 Alwen Proposed Southern Substation SPEN (Clocaenog) Substation Route A Route B Atkins - North 1 connection route Atkins - North 2 connection route Atkins - South 1 connection route Atkins - South 2 connection route Atkins - South 3 connection route 0 0 0 6 5 3
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Drawing by: Kate Oates Innogy Renewables UK Limited Baglan Bay Innovation Centre 0 Central Avenue 0
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Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Central Avenue Baglan Energy Park Port Talbot SA12 7AX
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Project: Alwen Forest Wind Farm, Conwy/Denbighshire Title: Figure 2.4: Alwen Forest Wind Farm: Grid Corridors 0 0
0 Key 8 5 3 Proposed Southern Substation SPEN (Clocaenog) Substation Corridor 1 Corridor 2 0 0 0 6 5 3
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0 Innogy Renewables UK Limited
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Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Central Avenue Baglan Energy Park Port Talbot SA12 7AX
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Project: Alwen Forest Wind Farm and Grid Connection, Conwy/Denbighshire Title: Figure 9.1: Survey areas overview 0
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5 Area B 3 Drawing by: BSG Ecology Merlin House Area C 1 Langstone Business Park Langstone, Newport NP18 2HJ
Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Service Layer Credits: Sources: Esri, HERE, Garmin, Intermap, increment P Central Avenue Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Baglan Energy Park Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), (c) OpenStreetMap contributors, and the GIS User Community Port Talbot SA12 7AX
296000 298000 300000 302000 Project: Alwen Forest Wind Farm and Grid Connection, Conwy/Denbighshire Title: Figure 9.2: Phase 1 Habitat Survey Results (Area A)
Key Corridor 1 Corridor 2 Coniferous plantation woodland
D Scattered scrub ! Broadleaved tree D Scattered bracken S S S S S S Running water ! Wall S S SD S S S! D Dry ditch SI S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S D D D D D D D D Acid flush ! D S S S S S S S S S S S S S S S S D D D D D D D D Acid grassland ! ! S S S S S S S SI S S S S S S S S S S S D D D D D D D D ! ! Bare ground D D ! ! ! ! D D S S S S S S Broadleaved plantation woodland S D S S S S S S S S S D D D DS S S S S S S ! ! ! ! SI Broadleaved semi-natural woodland D SI S S S S S S S S S S S S S S S SD S S S S S S S S S S S S S S S S S S S S S S S S Building D D SI S S S S S S S S S S S S S S S S S Continuous bracken S S S S S S S S S S S Dense scrub S S S S S S S S S SI S S S S S S S S D SI D Dry heath S S SI S S S S S S S S S S S S S S SS D S S S S S S
0 D ! Dry heath/acid grassland mosaic 0 D ! ! D D
0 D D ! SI 4 SI DD ! !D D D Ephemeral or short perennial 5 S SD S S S S S S S S S S S S S SD DSD S S S SSI DSI DI I
3 SI D SI ! ! !D D I D Improved grassland D SI D D D ! ! ! I I I S S S S S S S S S S S S S S S D! S S S S S DSD D D Marshy grassland D D D SI SI D SI I I I I I D DD Mixed plantation woodland S S S S S S S S SD SD S SSDI S S S S S S D D S SSI Poor semi-improved grassland D I I I I I D D S D S S S S S S I S DSI S S DS S S S S S S S SI Semi-improved acid grassland I I I I DI D S S D SI Semi-improved neutral grassland D D I I IS I S I S SI S S S Spoil D I I I I I S S S Tall ruderal S S S
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Drawing by: BSG Ecology Merlin House 1 Langstone Business Park Langstone, Newport NP18 2HJ
F
Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Central Avenue Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS Baglan Energy Park User Community Port Talbot SA12 7AX 298000
Project: Alwen Forest Wind Farm and Grid Connection, S S Conwy/Denbighshire
S S Title: ! ! ! ! ! ! ! ! ! ! Figure 9.3: Phase 1 Habitat ! ! ! ! ! Survey Results (Area B) ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! S S ! ! ! ! ! Key ! ! ! ! ! ! ! ! S S Corridor 1 ! SI ! ! Corridor 2 ! ! ! S S S S S S S S S S S Coniferous plantation woodland I I I I I I I ! ! ! ! D Scattered scrub I I I SI IS I S I S ! ! I I I I S SDD SD S S S S S S S S I D D Running water I I I I I I ISI I I I I I I I I I I I I SI S S S S S S S S S S S S | | | | Fence I I I I I I I I I I I I I I I S S S S S S Wall I I I I I I I Dry ditch SI I I I IS I S I SI IS I S I S Acid grassland ! !
! ! ! ! Bare ground I I I | I
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S | S S S S S S
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! ! ! ! !| ! ! Broadleaved semi-natural woodland
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I I I I| I
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! ! ! ! ! ! | S!I | S S S S S S S| S S Coniferous plantation woodland (felled)
I !I !| I! !I ! ! !| S S S S S S S S | | | Dense scrub ! !| ! ! ! !| ! S S SS S SS S SS S SS I DS I |SI IS | S S | | ! ! !| ! | ! ! ! Dry heath SDS S S S | | SI D ! ! ! S S S S S S! S! ! ! Dry heath/acid grassland mosaic 0 D D
0 D D
0 SI D D Ephemeral or short perennial
4 D D
S 5 S S S S S S D ID 3 D D Improved grassland I I I S S S S S S S Marshy grassland S S SI Poor semi-improved grassland S S S S S S S S Q SQ Q Quarry Q QSIQ Semi-improved acid grassland SI Semi-improved neutral grassland S S S S S S Spoil S S S Standing water Tall ruderal
SI S S S S S S Scale @ A3: 1:5,250 S S S SSI S S Coordinate System: British National Grid Licence. S S S S S S S S 0 50 100 200 Meters S S S S S S SI S ¯ SI D D D Q QD Q QD Q QD Q S S S S S S S S Date: 15-10-19 Prepared by: COH Checked by: OG D QD QD QD QD QD QD QD SI DDQ QD DQ QDDQ QD DQ D S S S S S S S SI S S S S S S Ref: D QD QD QD QD QD QD QD DQ Q DQ QDDQD Q DQ DQ Q D D DDD DD D S S S S SI S S S S S S S S Drawing by: D QD QD Q Q Q BSG Ecology D DDQ QD Q Q Q Merlin House S S S SSI S S S S S S 1 Langstone Business Park D QD QD Q Q Q SI Langstone, Newport F DD D S S S S S S S S SSI S S NP18 2HJ SI S S S S S S S S S S S
S S S S S S S F Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Central Avenue Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS Baglan Energy Park User Community Port Talbot SA12 7AX
298000 300000 D D D D D D DD D D D D D DDD D DD D D D Project: D DD DD DDDD D D D D Alwen Forest Wind Farm D D DDDD D D D D D D D D D D and Grid Connection, D D D D D D D D D D Conwy/Denbighshire D D D D D Title: D D D D D DD D Figure 9.4: Phase 1 Habitat D D D D Survey Results (Area C) S S S S S S S S S S S S S S S D D S S S S S S S S S S S S S S S DSI Key D S S S S S S S S S S S S S S S D Corridor 2 Coniferous plantation woodland S S S S S S S S S S S S S S S D Scattered scrub S S S S S S S S S S S S S IS I S I SI S S S S S S S S S S S S Running water I I I I S SI S S S S S S S S S S S S S S S S S S S S S S S S S S S I I I I Wall S S S S S S S S S S S S S S S S S S S S S S S S S S S S Dry ditch
S SDD SD S S S S S S S S S S S S S S S S S S S S S S S S S Broadleaved semi-natural woodland D D I I I I I S S S S S S S S S S S S S S S S S S S S S S S S S S Dense scrub I I I I I Dry heath S S S S S S S S S S S S S S Dry heath/acid grassland mosaic S S S S S S S S S S S S S S D D D D D Ephemeral or short perennial D D D D D S S S S S S S S S S S S S S D D D D D Marshy grassland S S S S S S S S S S S S S S S S S S S S S S S Mixed plantation woodland S S S S S S S S S S S S S S S S S S S S S S S SI Poor semi-improved grassland S S S SI S S S S S S S S S S S S S SI Semi-improved acid grassland 0 S S S 0
0 SI Semi-improved neutral grassland 4
5 S S S S S S S S S S S S S 3 Tall ruderal S S S S S S S S S S S S S
S S S S S S S S S S S S S
S S S S S S S S S S S S S
S S S S S S S S SI S S S S Scale @ A3: 1:5,250 S S S S S S S S S S S S S Coordinate System: British National Grid Licence. S S S S S S S S S S S S S 0 50 100 200 Meters S S S S S S S S S S S S S ¯
S S S SSI S S S S S S S S S Date: 15-10-19 Prepared by: COH Checked by: OG
S S S S S S S S S S S S S S S Ref: SI S S S S S S S S S S S S S S S Drawing by: SI BSG Ecology Merlin House S S S S S S S S S S 1 Langstone Business Park Langstone, Newport SI D NP18 2HJ S S S S S SI S S S S S S S S
S S S SSI S S S S S S S S S
S S SI S S S S S S Client: SI Innogy Renewables UK Limited S S SI S S S SSI S S Baglan Bay Innovation Centre Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Central Avenue Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS Baglan Energy Park User Community S S S S S S S S Port Talbot SA12 7AX S S S S S S S 300000 300000 I I I I I I I I I I Project: I I I I I I I I I I Alwen Forest Wind Farm I I I I I I I I I I and Grid Connection, I I I I I I I I I I Conwy/Denbighshire I I I I I I I I I I Title: I I I I I I I I I I Figure 9.5: Phase 1 Habitat I I I I I I I I I I Survey Results (Area D) I I I I I I I I I I I I I I I I I I I I Key I I I I I! ! I ! !I !I! I! ! I ! ! I I I I I! !I ! I! !I ! I! !I ! ! Corridor 1 ! ! ! ! ! ! ! ! ! ! I I I I I !I I! I ! I !I ! ! ! ! ! ! Corridor 2 I I I I I! ! I ! !I !I! I! ! I ! ! ! ! ! ! ! ! ! ! ! ! Coniferous plantation woodland ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D Scattered scrub ! ! ! ! ! ! ! ! ! ! Running water Dry ditch ! ! ! ! ! ! ! ! ! ! Bare ground ! ! ! ! ! Broadleaved semi-natural woodland Dense scrub Dry heath Dry heath/acid grassland mosaic D D D D D D D D Ephemeral or short perennial D D D D D D D D D D Marshy grassland Mixed plantation woodland D D D D D D D D SI Semi-improved acid grassland D D DD D D D D D D D D D D D D Standing water D D DD D D D D D D D D D D D D Tall ruderal D D DD D D D D D D D D D D D D D D DD D D D D D D D D D D D D D D DD D D D D Scale @ A3: 1:5,250 D D D D D D D D Coordinate System: British National Grid D D DD D D D D Licence. D D D D D D D D D D D D D D D 0 50 100 200 Meters D D D D D D D D D D D D D D D DD D D D D DD D D ¯ D D DD DD D DDD D D D D D D D D D DD D D DDD D DD D D DD D D D D D Date: 15-10-19 Prepared by: COH Checked by: OG D D D D D D D D D D D DD D D D D DD D D D D D D D D D DD D D Ref: D D D DD DD D D D D D D D D D D D DD D D D D D D D D D D D Drawing by: D D DD D D D BSG Ecology D D D D D D D D D D D Merlin House D DD D D D D 1 Langstone Business Park DD DD DDD DD D D D D D Langstone, Newport D D D NP18 2HJ D D D DD D D D D D DDDD DD D D D D DD DD DD DDDD D D D D D D DDDDD D D D D D D D DD D D D D Client: DD D D D D D D D D Innogy Renewables UK Limited D D Baglan Bay Innovation Centre D D DD Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Central Avenue D D Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS Baglan Energy Park D User Community D D D Port Talbot D SA12 7AX DD D D 300000 300000 D D D D D D Project: D D D D D D D D D Alwen Forest Wind Farm D D D D D and Grid Connection, D D D Conwy/Denbighshire D D D Title: D D D Figure 9.6: Phase 1 Habitat D D Survey Results (Area E) DD ! ! ! ! ! ! D ! ! ! ! ! ! ! ! ! ! ! ! Key ! ! ! ! ! ! Corridor 1 ! ! ! ! ! ! ! ! ! ! ! ! Corridor 2 ! ! ! ! ! ! ! ! ! ! ! ! Coniferous plantation woodland ! ! ! ! ! ! D Scattered scrub ! ! ! ! ! ! Running water Dense scrub
D Dry heath D Dry heath/acid grassland mosaic S S S D SI Poor semi-improved grassland S S S D Standing water Swamp I I I I Tall ruderal I I I I Wet heath I I I I S S I I I SII S S I I I I I I SI IS I I I I I I I I I I I I I I I I I I I I I I I I Scale @ A3: 1:5,500 Coordinate System: British National Grid I I I I Licence. I I I I I I I I 0 50 100 200 Meters ¯ I I I I I I I I Date: 15-10-19 Prepared by: COH Checked by: OG
I I I I Ref: I I I I Drawing by: I I I I BSG Ecology Merlin House I I I I 1 Langstone Business Park Langstone, Newport I I I I NP18 2HJ I I I I I I I I I I I I Client: Innogy Renewables UK Limited 0 I I I I
0 Baglan Bay Innovation Centre
0 Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Central Avenue 6 I I I I Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS
5 Baglan Energy Park User Community 3 Port Talbot I I I I SA12 7AX I I I I 300000
Project:
|
|
| ! ! ! ! ! ! ! ! ! ! | ! !
| ! ! ! ! ! ! ! ! ! ! | ! !
|
| Alwen Forest Wind Farm |
! ! ! ! ! ! ! ! ! ! ! | !
! ! ! ! ! ! ! ! ! | ! ! ! | | ! ! ! ! ! ! ! ! !| ! ! ! and Grid Connection, ! ! ! ! ! ! ! ! ! ! ! ! | | | ! ! ! ! ! ! ! ! ! | ! ! | ! ! ! ! ! ! ! ! ! ! |! ! | ! Conwy/Denbighshire | | | ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! | ! !| ! ! ! | | | ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Title: ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Figure 9.7: Phase 1 Habitat ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Survey Results (Area F) ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Key ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Corridor 1 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Coniferous plantation woodland ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D Scattered scrub ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Running water ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! | | | | | Fence ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Dry ditch ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Bare ground ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Building ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Continuous bracken ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Dry heath ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Dry heath/acid grassland mosaic ! ! ! ! ! ! ! ! ! ! Marshy grassland ! ! ! ! ! ! ! ! ! ! S S SI S Poor semi-improved grassland ! ! ! ! ! Standing water ! ! ! ! ! S S S ! ! ! ! ! Swamp ! ! ! ! ! ! ! ! ! ! Tall ruderal ! ! ! ! ! Wet heath ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 0
0 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 0 ! ! ! ! S! S! ! ! ! ! ! ! ! ! ! ! ! ! 8 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 5 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 3 ! ! ! ! ! ! ! ! S! ! S! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! SI ! ! ! ! ! ! ! ! S! ! S! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Scale @ A3: 1:5,500 ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Coordinate System: British National Grid ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! S! S! ! ! ! ! ! ! ! ! ! ! ! ! Licence. ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D! ! ! ! ! ! ! ! ! ! S! S! S! ! ! ! ! ! ! ! ! ! ! ! ! ! 0 50 100 200 Meters ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ¯ ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! S SSI S ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Date: 15-10-19 Prepared by: COH Checked by: OG ! ! ! ! S! ! S! ! S! ! ! ! ! ! D ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Ref: ! ! ! ! S! ! S! ! S! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Drawing by: ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D ! ! ! ! ! ! ! ! ! ! ! ! ! ! BSG Ecology ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Merlin House 1 Langstone Business Park ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Langstone, Newport ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! NP18 2HJ ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D D ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !D! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D Client: ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Innogy Renewables UK Limited ! ! ! ! ! ! ! ! ! D ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D ! ! ! ! ! ! ! ! ! Baglan Bay Innovation Centre ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! D! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Central Avenue Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS Baglan Energy Park ! ! ! ! ! !D ! ! ! ! ! ! ! ! !D ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! User Community D Port Talbot ! ! ! ! ! ! ! ! ! ! ! ! D! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! SA12 7AX D D 292000 294000 296000 298000 300000 302000 304000 306000 Project:
The Zone of Theoretical Visiblity (ZTV) is calculated Alwen Forest Wind Farm for assumed locations of wooden poles with a height of 12m, with assumed 200m spacing along and Grid Connection, the edge and centre line of corridors 1 and 2, from a 0 Conwy/Denbighshire 0 viewing height of 2m above ground level. The 0
2 visibility of the poles was ran to 4km. Title: 6
3 The terrain model assumes bare ground and is derived from OS Terrain 50 height data (obtained Figure 11.1: ZTV from Ordnance Survey in July 2017). Earth curvature and atmospheric refraction have of the Overhead Power Line been taken into account. The ZTV was calculated and Poles within 4km using ArcMap 10.5.1 software. Key
Corridor 1 0 0 0 0
6 Corridor 2 3
4km from corridor 1 and 2
. Viewpoint location
1: Llyn Brenig Visitor Centre 0
0 2: Alwen Dam 0 8 5 3 6: Brenig Archaeological Trail
10: Craig Bronbanog . VP6 Theoretical zone of visibility Higher proportion of grid connection corridor is visible
0 0 0 6
5 Lower proportion of grid connection 3 corridor is visible
. VP1 0 0 0 4 5 3 Scale @ A3: 1:55,000 Coordinate System: British National Grid Licence. © Crown copyright and database rights 2019 Ordnance Survey 0100031673. . VP2 0 0.250.5 1 km ¯
0 Date: 16-10-19 Prepared by: EL Checked by: EW 0 0
2 VP10 5 .
3 Ref:
Drawing by: LUC Atholl Exchange 6 Canning Street Edinburgh 0 0 0 0 5
3 Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Central Avenue Baglan Energy Park Port Talbot SA12 7AX
292000 294000 296000 298000 300000 302000 304000 306000 292000 294000 296000 298000 300000 302000 304000 306000 Project:
The Comparative Zone of Theoretical Visibility Alwen Forest Wind Farm (CZTV) is calculated to turbine tip height of 200m and assumed locations of wooden poles at 200m and Grid Connection, spacing along the edge and centre line of corridors 0 Conwy/Denbighshire 0 1 and 2, from a viewing height of 2m above ground 0
2 level. The visibility of the poles was ran to 4km. Title: 6
3 The terrain model assumes bare ground and is derived from OS Terrain 50 height data (obtained Figure 11.2: CZTV of the from Ordnance Survey in July 2017). Earth curvature and atmospheric refraction have Proposed Wind Farm Turbines, been taken into account. Overhead Power Line and Poles The ZTV was calculated using ArcMap 10.5.1 software. Key
Corridor 1 0 0 0 0
6 Corridor 2 3
4km from corridor 1 and 2
SPEN Clocaenog substation
Alwens Southern substation
0 !!
0 Proposed turbine 0 8 5 3 . Viewpoint location
1: Llyn Brenig Visitor Centre . VP6 2: Alwen Dam
6: Brenig Archaeological Trail 0 0
0 10: Craig Bronbanog 6 5 3 Theoretical infrastructure visibility 1 2 !! !! Only the proposed wind farm is visible 4 3 ! ! ! ! 5 Only the proposed corridor is visible !! . VP1 6 !! Both proposals are visible 0 0 0 4
5 7 3 !! Scale @ A3: 1:55,000 8 Coordinate System: British National Grid !! Licence. © Crown copyright and database rights 2019 9 Ordnance Survey 0100031673. !! . VP2 0 0.250.5 1 km ¯
0 Date: 16-10-19 Prepared by: EL Checked by: EW 0 0
2 VP10 5 .
3 Ref:
Drawing by: LUC Atholl Exchange 6 Canning Street Edinburgh 0 0 0 0 5
3 Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Central Avenue Baglan Energy Park Port Talbot SA12 7AX
292000 294000 296000 298000 300000 302000 304000 306000 296000 298000 300000 302000
Project: Alwen Forest Wind Farm and Grid Connection, Conwy/Denbighshire ") Title:
100715 Figure 13.1: Heritage assets within the grid corridors DE088 (! Key 0 0
0 13786 ") SPEN Clocaenog Substation 8 (! 5 3 (! Registered Historic Landscape 13785 13781 Proposed substation Scheduled Monument (! 13779 (! CPAT HER records (! Corridor_1
13778 (! Corridor_2
! 13777 (
13774 (!(!
0 13775 0 0 6 5 3
13763 (!
Scale @ A3:1:25,000 Coordinate System: British National Grid
Licence. (! 13760 13668 36823 0 0.25 0.5 1 km ¯
81836 Date: 17-10-19 Prepared by: JR Checked by: MK (! (! Ref:
0 (! 13735 0 1 0 00675
4 (! Drawing by:
5 (! 3 ! 104551 Headland Archaeology ( 13759 Midlands & West Unit 1 Clearview Court 100674 (! Twyford Road 100666 Hereford (! (! HR2 6JR DE283
Client: Innogy Renewables UK Limited Baglan Bay Innovation Centre Central Avenue Baglan Energy Park Port Talbot SA12 7AX
296000 298000 300000 302000 294000 296000 298000 300000 302000 304000
Project: Alwen Forest Wind Farm
! ! ! ! ! and Grid Connection, ! ! ! ! ! Conwy/Denbighshire ! ! ! ! Title: !
!
!
0 (! ! 0 ! 0 ! ! ! ( ( 0 6 ! Figure 13.2: Heritage assets 3 (! ! (! (! (! ! within the study area ! (! ! ! ! ((! Key (!(! (! (! (! (! ! ! (! (! )" SPEN Clocaenog Substation (!
! ! (! (! (! (! (! (! (! Proposed substation (! (!
! ! (!(!(!(!(! (! (! Corridor_2 )" (!(!(! ! (! (! ! (! (! (! Corridor_1 !
( ! ! (! (! Alternative access track (! (! (! ! ! (!(! ! ! Proposed turbine
0 ! (! (! !(( 0 (! ( !
(! ! 0 ! (! Proposed crane pad 8 ( (! (! (!
5 (! ! (!
(! ! ! 3 (! (!(! ( Proposed new track
! !
(! ! (! (! Existing track to be upgraded (!
! ! ! !( Potential substation link track (! (! (!
! ! ! ( (! (! Potential borrow pit
! ! ! (! (!( Potential borrow pit track
(! !
! (! (! (! E Grade II Listed Building !
! ! ! ! (! (! ! ! (! CPAT HER records ! !
! ! ! ! ! (! ! ! ! ! (! ! (! (! Scheduled Monument ! (! (! ! (! (! (! ! ! 0 (! Registered Historic Landscape
0 (! (! ! ! ( ! 0
6 Site boundary (! !
5 ! (! (!(! !
(! (! ( ! 3 ! ! (! (! (! ! Study Area ! (! (! (! (!(! (!
(! (!(! ! ! (! 1 2 (!
(!! Route Options ! (!
(! (! (! Route A (! ! South 1
! (! 4 (! 3 ! Route B South 2 ! (! ! (! ((! (! (! ! 5 (! ( ! North 1 South 3 ! (! (! (! (! (! North 2 (! (! (! (!! ! (! (! (!
(! 6(! (! (! !
! (! (! (! Scale @ A3:1:40,000
(! ! Coordinate System: British National Grid 0 (! (! (! ! (! 0 ! (! (! 0 (! (!
(! (! (! ! Licence. 4 (! (! (! (!(! ! 5 (! (!(! 3 (! 7 (! !
! (!(! (! (! 0 0.25 0.5 1 km
(!(!(! (! (! (! (! ! ! ¯ (! (!
8 E (! !
(! !
(! (! ! Date: 17-10-19 Prepared by: JR Checked by: MK (! (!
(! ! ! 9 (! (! (! (! (!
(! (! ! Ref:
! ! (! (! E (! (!
(!(! (! !
! ! (! ! Drawing by:
(!(! ( (!
! ! (! (! Headland Archaeology
! Midlands & West ! (!
(! (! Unit 1 Clearview Court (! !
! E (! ! Twyford Road
0 ( (! Hereford ! 0
! (! (!
0 (!(! (! HR2 6JR ! ! ! ! ! (! ! ( ( ( ( ( ! 2 (! (! (!
5 (! !
3 (! !
! (! (!
!
! ! ! ! ! (!(
! (! (! !
!
!
! (! Client: !
!
!
! ! !
! !
! ! Innogy Renewables UK Limited !
! Baglan Bay Innovation Centre Central Avenue Baglan Energy Park Port Talbot SA12 7AX
294000 296000 298000 300000 302000 304000