7. ECOLOGY

7.1. Introduction

1. This chapter presents the assessment of the likely significant effects (as per the “EIA Regulations”) on the environment of the Berwick Bank Wind Farm onshore transmission works (OnTW) (the Proposed Development) on ecology. Specifically, this chapter considers the potential impact of the Proposed Development landward of Mean Low Water Springs (MLWS) during the construction, operational and maintenance, and decommissioning phases.
2. This assessment is informed by the following technical chapters:

• Chapter 5 Proposed Development Description; and
• Chapter 8: Onshore Ornithology.
  3. This chapter summarises information contained within:
• Volume 4, Appendix 7.1: Preliminary Ecological Appraisal (PEA) including Desk Study;
• Volume 4, Appendix 7.2: Protected Species Survey Report;
• Volume 5, Confidential Appendix 7.2a: Badger Survey Results;
• Volume 4, Appendix 7.3: Bats; and
• Volume 4, Appendix 7.4: Great Crested Newt Species Protection Plan.

7.2. Purpose of this Chapter

4. This chapter:

• Presents the existing environmental baseline established from desk studies, site-specific surveys, and consultation with stakeholders;
• Identifies any assumptions and limitations encountered in compiling the environmental information;
• Presents the potential environmental impacts on ecology arising from the Proposed Development, and reaches a conclusion on the likely significant effects on ecology based on the information gathered and the analysis and assessments undertaken; and
• Highlights any necessary monitoring and/or mitigation measures recommended to prevent, minimise, reduce or offset the likely significant adverse environmental effects of the Proposed Development on ecology.

7.3. Baseline Study Area

5. Appropriate survey areas for each specific survey were derived from areas with available access plus best practice guidelines as follows:

• Ecological Desk Study Area: the Planning Application Boundary (the ‘site’) and 5 km radius;
• Extended Phase 1 Habitat Study Area: the site plus accessible areas[1] up to 250 m;
• Great crested newt (Triturus cristatus) Study Area: Waterbodies within the site plus accessible waterbodies up to 500 m;
• Otter (Lutra lutra) Study Area: Watercourses within the site plus accessible watercourses up to 250 m;
• Bat Study Area: the site plus accessible areas up to 50 m;
• Water vole (Arvicola amphibius) Study Area: the site plus accessible areas up to 50 m; and
• Badger (Meles meles) Study Area: the site plus accessible areas up to 100 m.
• The extents of the above study areas are shown in Volume 2: Figure 7.1   Open ▸

7.3.1.    Intertidal Area – Interface between Onshore and offshore Projects

6. The planning application boundary for the Application extends to MLWS.  The infrastructure to be located between MHWS and MLWS consists of cables to be installed via trenchless technology (e.g. Horizontal Directional Drilling (HDD)).  Impacts associated with this infrastructure have been assessed in the Offshore EIA Report (Volume 2, Chapter 8), although given the commitment to use trenchless technology no likely significant effects have been predicted.
7. The Offshore EIA Report is available online at the Berwick Bank Wind Farm website; www.berwickbank.com. An electronic copy has been submitted to East Lothian Council Planning Department.
8. The potential effects of the onshore infrastructure located above MHWS on the intertidal area have been assessed in this chapter.

7.4. Policy and Legislative context

9. Policy, guidance and legislation in relation to ecology, is set out in detail in Volume 4, Appendix 7.1 of the Onshore EIA Report and, in addition, all relevant planning and legislative policy is detailed in full in Volume 1, Chapter 3. A summary of policy, guidance and legislative provisions relevant to ecology are provided in Table , 7.2 and 7.3 below.

Table 7.1: Summary of Planning Policy Relevant to Ecology

Table 7.2: Summary of Planning Guidance Relevant to Ecology

Table 7.3: Summary of Legislation Relevant to Ecology

7.5. Consultation

10. A summary of the key issues raised during scoping and consultation activities undertaken to date specific to ecology are presented in Table 7.4 and 7.5, below, together with how these issues have been considered in the production of this ecology chapter. Further detail is presented within Volume 1, Chapter 2 of the Onshore EIA Report and the Pre-Application Consultation (PAC) Report.

Table 7.4: Consultation on the Proposed Development: Scoping Opinion

Table 7.5: Summary of Relevant Consultation Undertaken to Date

7.6. Methodology to Inform Baseline

11. This section identifies the ‘key ecology and nature conservation issues’ which have been considered as part of the Ecological Impact Assessment (EcIA), describes the methods used to establish baseline conditions and assess the magnitude and significance of the likely ecological effects of the Proposed Development.

7.6.1.    Design Iteration

12. The following assessment is based on the final onshore cable route, which has undergone various iterations over an extended process that has taken into consideration a variety of potential constraints. Ultimately, the final design (Volume 2, Figure 5.1) is one that has taken into consideration all of these constraints to lessen the potential for any impacts to be experienced by any single receptor across the variety of disciplines that have all provided input into the Proposed Development’s final layout (further details on design iteration are provided in Volume 1, Chapter 4).

7.6.2.    Ecological Desk Study

13. Information on ecology within the ecological desk study area was collected through a detailed desktop review of existing studies and datasets.
14. In terms of statutory nature conservation designations, the desk study identified any international and national designations, such as Special Areas of Conservation (SACs), SSSIs, National Nature Reserves (NNRs) or Local Nature Reserves (LNRs) within 5 km of the Site. Any non-statutory designations, such as Environmentally Sensitive Areas (ESA), Local Biodiversity Sites (LBS), Local Nature Conservation Sites (LNCS), Sites of Interest for Nature Conservation (SINCs), Scottish Wildlife Trust Reserves (SWTR) or woodland areas included on the Ancient Woodland Inventory (AWI), were identified within a 2 km distance of the Site. Note that only ecological (biological) features were considered relevant to the present study and that designations for bird interests are considered separately within Volume 1, Chapter 8 and therefore omitted from the present chapter.
15. Existing records for protected or otherwise notable species (e.g. Scottish Biodiversity List (SBL)/LBAP priority species) were identified within a 5 km distance of the Site. Only records from the last 10 years were considered relevant to the study.
16. These are summarised in Table 7.6 below.

Table 7.6: Summary of Key Desktop Studies & Datasets

7.6.3.    Site-Specific Surveys

17. To inform the ecology chapter, site-specific surveys were undertaken, to a scope agreed with NatureScot.(Table 7.4). A summary of the surveys undertaken to inform the EcIA is outlined in Table 7.7 below.

Table 7.7: Summary of Site-Specific Survey Data

7.6.4.    Evaluation Methods for Ecological Features

18. Table 7.8   Open ▸ below lists the criteria used to determine the value of ecological features in a geographical context.

Table 7.8: Geographical Evaluation Criteria

19. Where a feature qualifies under two or more criteria, the higher value is applied to the feature.
20. Within this chapter, any ecological feature of local or higher value is considered an Important Ecological Feature (IEF).

7.7. Baseline Environment

7.7.1.    Overview of Baseline Environment

21. This section of the chapter details the results of the ecological desk study and field surveys conducted along the onshore cable corridor and respective study areas, providing the baseline conditions from which an impact assessment is based. This includes:

• Review of designated nature conservation sites and existing species data;
• Habitat information from field surveys; and
• Protected or otherwise notable species information from field surveys.
  22. The full list of protected species (including common and widespread species not considered as part of the assessment) identified in the desk study and/or field surveys are listed with their scientific names in Volume 4, Appendix 7.1.

7.7.2.    Nature Conservation Designations

23. As detailed in Table 7.9 below, five statutory nature conservation designations of national importance are present within 5 km of the Site. No international designation is present within this distance. In addition, five non-statutory local designations are present within 2 km. Statutory nature conservation designations are shown on Volume 2, Figure 7.2   Open ▸ , and non-statutory nature conservation designations are shown on Volume 2, Figure 7.3   Open ▸

Table 7.9: Nature Conservation Designations

24. Additionally, 29 areas of AWI were identified within 2 km of the Site, including two AWI within or partly within, and three immediately adjacent to, the Site, as shown on Volume 2, Figure 7.3.

7.7.3.    Protected or Otherwise Notable Species Records – External Data

25. Table 7.10   Open ▸ below summarises baseline ecology data from the ecological desk study (see Volume 4, Appendix 7.1).

Table 7.10: Protected or Otherwise Notable Non-avian Species

26. Please refer to Volume 1, Chapter 8 for records of protected or otherwise notable bird species.

7.7.4.    Field Surveys

27. Specific details relating to the field survey methodologies and results are included within each of the relevant Volume 4, Appendices 7.1, 7.2 and 7.3. The following sections summarise the baseline conditions with a summary of relevant results used to inform the assessment of likely ecological impacts provided below.
28. The locations of ecological features are presented in full in Volume 4, Appendices 7.1, 7.2 and 7.3 and associated Appendix Figures: 7.1.4-5, 7.2.1-2 (Appendix Figure 7.2.3 is confidential and presented in Confidential Volume 5), and 7.3.1-2.

7.7.5.    Habitats

29. In 2020 the extended Phase 1 habitat study area comprised the full site and a 250 m buffer, as shown in Volume 4, Appendix 7.1, Appendix Figures 7.1.4-5. In addition, a National Vegetation Classification (NVC) survey was undertaken of all wetland communities recorded. This level of survey effort aimed to inform the design process, to allow for mitigation through design and reduce potential negative impacts on ecological receptors.
30. This EcIA considers habitats within the potential zone of influence of the Proposed Development, namely the potential works areas (i.e. the development footprint, temporary construction compounds/ laydown areas, access tracks) and a 250 m buffer as shown on Volume 2, Figure 7.4   Open ▸ (herewith referred to as the ‘ecology study area’).
31. The Phase 1 habitat survey results are shown on Volume 2, Figure 7.4   Open ▸ and summarised in Table 7.11. The Phase 1 analysis was informed by an extended Phase 1 habitat survey in July and October 2020. In addition to summarising the Phase 1 habitats within the site, Table 7.11 also details those specifically present within the ecology study area. Volume 4, Appendix 7.1 should be consulted for full descriptions, including Target Notes, of habitats found within the ecology study area. Note that the original Phase 1 habitat survey documented in Volume 4, Appendix 7.1 was undertaken to inform the location of the Proposed Development and the document therefore includes a larger survey area and describes some habitats that are not present within the ecology study area as defined above.

 Table 7.11: Phase 1 Habitats within the Study Area

32. A brief description of the Phase 1 habitats is presented below. For full descriptions and scientific names of species please refer to Volume 4, Appendix 7.1.

Broadleaved, semi-natural woodland (A1.1.1)

33. Mature, semi-natural broadleaved woodland extends along the Braidwood Burn, Thornton Burn, Thurston Burn and Ogle Burn corridors that run through the southern reaches of the ecology study area. The canopy is dominated by ash, beech and oak with occasional Scots pine. Thornton Glen SWT, Thurston Burn Valley LNCS and Dunglass Burn LNCS form part of this woodland area, though all sites lie outwith the footprint of the Proposed Development. A small area of broadleaved woodland lies to the south-east of Thortonloch Holdings, also outwith the footprint of the Proposed Development. This woodland is listed on the AWI as Long-Established woodland of Plantation Origin (LEPO 2b).

Dense and scattered scrub (A2.1 and A2.2)

34. Dense and scattered scrub is mainly associated with the Braidwood Burn and Thornton Burn corridors with extensive areas of gorse and blackthorn recorded on the steep banks of the watercourses and bordering the woodland. Gorse scrub is also associated with the Dry Burn that runs through the northern reaches of the ecology study area.

Semi-improved neutral grassland (B2.2)

35. This habitat was mainly recorded within the northern reaches of the ecology study area near the landfall location, west of Torness Point, with smaller extents recorded along the Braidwood Burn corridor at the south of the ecology study area. Plant species recorded in this habitat included false oat-grass, cock’s-foot, crested dog’s-tail, wavy hair-grass, meadow fescue, sheep’s-bit, devil’s-bit scabious, common knapweed and tormentil.

Improved grassland (B4)

36. Improved grassland fields used for grazing and hay production account for almost half of the ecology study area. Due to the managed nature of this habitat, it was generally species-poor, with swards dominated by perennial rye-grass, Yorkshire-fog and white clover. Field boundaries include stone walls and species-poor defunct and intact hawthorn hedgerows. Greater species diversity was found along the field margins and hedgerow understorey.

Open and Standing water (G and G1)

37. Three waterbodies lie within the ecology study area, two are within the Viridor site to the northwest of the Proposed Development and one is located to the east of the Proposed Development, north of Skateraw. All waterbodies lie outwith the footprint of the Proposed Development. The North Sea lies within the northern reaches of the ecology study area.

Running water (G2)

38. Running water within the ecology study area includes Braidwood Burn, Thornton Burn, Thurston Mains, Ogle Burn and Branxton Burn which run through the southern reaches of the ecology study area. Skateraw Dean and the Dry Burn run through the northern reaches of the ecology study area. A network of drainage ditches and unnamed watercourses also cross the ecology study area. The Skateraw Dean, Braidwood Burn and an unnamed watercourse to the south of the A1, lie under the footprint of the Proposed Development.

Intertidal (H1.1 and H1.3)

39. The proposed landfall location at Skateraw, west of Torness, is characterised by coastal habitats including boulders and rocks within the intertidal zone. Species recorded within this habitat included biting stonecrop, bladder wrack, spiral wrack, oarweed and sea lettuce. The intertidal biotopes and habitats are described in more detail within Volume 2, Chapter 8, Section 8.7 of the Offshore EIA Report.

Arable (J1.1)

40. Arable fields used for cereal and crop production account for just over a quarter of the ecology study area. Monocultures of oat, barley and brussels sprouts were recorded at the time of the field survey. Field boundaries included stone walls and species-poor defunct and intact hawthorn hedgerows.

Other (J5)

41. The A1 trunk road runs through the site from east to west with smaller roads criss-crossing the site. The East Coast Main Line (ECML) railway also runs from the northwest of the site to the southwest, passing under the A1 trunk road. Ground within the boundaries of residential properties and farms was also mapped under this code.
42. All other habitat types present within the ecology study area make up a very small proportion of the overall site, each covering less than 1% of the total area (see Table 7.8).

7.7.6.    Invasive Non-Native Species

43. Japanese knotweed and Himalayan balsam were recorded within the site; including one stand of Himalayan balsam within the ecology study area (i.e. within 250 m of the Proposed Development).

7.7.7.    Groundwater Dependent Terrestrial Ecosystems (GWDTE)

44. As described within Volume 4, Appendix 7.1, bryophyte spring corresponding to the M37 Palustriella commutata-Festuca rubra spring community of the NVC, which is likely to be highly groundwater dependent (SEPA, 2017), was recorded within 250 m of the site (for location refer to Volume 4, Figure 7.1.1). However, no M37 or other wetland with the potential to be a GWDTE has been identified within the site itself or within the ecology study area.  

7.7.8.    Protected or Otherwise Notable Species

45. Full details of the survey methods, results and scientific names are included in Volume 4, Appendices 7.1, 7.2 and 7.3, with a brief summary provided below.

Otter

46. Evidence of otter presence was found within the ecology study area including a number of potential and confirmed resting sites, as follows:

• Two potential otter resting sites (hovers) identified along the Thornton Burn corridor;
• Three potential hovers identified along the Braidwood Burn corridor;
• Two potential and one active hovers identified along the Ogle Burn corridor; and
• Three potential holts and one active hover identified along the Dry Burn corridor. Further camera monitoring of the potential holts along the Dry Burn found no evidence that these are currently used by otter.
  47. The above watercourses, unnamed watercourses and drainage ditches that cross the site create a network of foraging and commuting routes for otter enabling movement of otter from coastal to inland habitats in response to prey availability.
  48. All resting sites identified lie outwith 30 m of the footprint of the Proposed Development.

Badger

49. The survey confirmed that badgers are active within the ecology study area with setts and field signs identified (as detailed within Confidential Volume 5, Appendix 7.2a). No setts were located within 30 m of the Proposed Development. A large mammal hole was identified during GI works in July 2022. The hole was large enough for badger but no badger field sign was found to confirm current use. Details of the hole location are noted within Confidential Volume 5, Appendix 7.2a). Arable fields, improved grassland fields and woodland areas within the Study Area provide suitable foraging, commuting and sett building habitat.

Water vole

50. No evidence of water vole was found during the surveys, and watercourses within the ecology study area were considered to be generally suboptimal for this species.

Bats

51. As described in Volume 4, Appendix 7.3, the Preliminary Roost Assessment survey identified a number of trees and one structure with features suitable for use by roosting bats. Further active season surveys were therefore completed in 2021 of features which lay within 30 m of the design options (based on the potential design options at the time of the survey). No evidence of roosting bats was found, with low numbers of soprano pipistrelle, common pipistrelle and Myotis bats being active. The habitats within the ecology study area were considered to have high suitability for use by foraging and commuting bats with riparian corridors, woodland edge habitat and linear features such as hedgerows and stone walls providing bats with excellent foraging and commuting routes through the ecology study area.

Great crested newts

52. As detailed in Volume 4, Appendix 7.2, an eDNA survey completed in 2021 confirmed great crested newt presence within a pond (‘Pond 1’) fed by Ogle Burn. The pond is located 450 m from the footprint of the Proposed Development at its nearest point. Suitable terrestrial habitat links the pond to the southern boundary of the site, along the Ogle Burn and Braidwood Burn corridor. However, the footprint of the Proposed Development, where it crosses the Braidwood Burn corridor, is over 500 m from the pond, which is generally considered to be the maximum distance great crested newts will migrate from their breeding ponds (Langton et al., 2001). Where the works footprint extends 50 m into the 500 m buffer, the habitat is improved grassland, which is suboptimal for this species.

Other amphibians

53. No incidental evidence of amphibians was recorded during the surveys. The small waterbodies and areas of slow-moving water within drainage ditches are likely to support common frog, common toad and small newt species.

Reptiles

54. No incidental evidence of reptiles was found during the surveys. Improved grassland and arable fields, which represent the majority of the ecology study area, are generally suboptimal for reptiles providing limited foraging, commuting and refugia habitat. However, areas of rough grassland and scrub particularly along the Dry Burn corridor, but also along the Braidwood Burn corridor and field margins, may support common lizards. The habitats within the ecology study area are considered less likely to support adder.

Fisheries

55. Due to the presence of impassable weirs on Thornton Burn, Dry Burn and Bilsdean Burn, migration of fish upstream is considered unlikely, and the desk study has not identified any resident populations of species of conservation interest, such as brown trout (Salmo trutta) or brook lamprey (Lampetra planeri), upstream of these weirs. Therefore, fish are scoped out of further assessment.

7.7.9.    Evaluation of Baseline Features

Nature Conservation Designations

56. The nature conservation designations identified are evaluated in Table 7.12: below. The value assigned to a nature conservation area corresponds to its level of designation, and where two or more designations overlap, the higher level applies.

 Table 7.12: Nature Conservation Designations Evaluation Summary

Ancient Woodland

57. Areas of AWI are of Council level importance. Of the 29 areas identified within 2 km of the Planning Application Boundary, two AWI lie within or partly within, and three immediately adjacent to the ecology study area. No AWI woodland lies within the footprint of the Proposed Development.  

Habitats

58. The habitat types recorded within the ecology study area are evaluated in Table 7.13, below, with reference to their extent and condition and potential fit with nature conservation priorities, including the SBL which is, in part, based on the former UK Biodiversity Action Plan (including the Maddock (2011) review used here) and the East Lothian Council BAP (ELCBAP).

Table 7.13: Habitats Evaluation Summary

Protected Species and Species Groups

59. Table 7.14 presents a summary of each non-avian species or species group, their conservation priority, a brief summary of condition and an evaluation in terms of ecological value.

 Table 7.14: Species Evaluation Summary

7.7.10.              Future Baseline Scenario

60. The Town and Country Planning (Environmental Impact Assessment) (Scotland) Regulations 2017 require that a “a description of the relevant aspects of the current state of the environment (baseline scenario) and an outline of the likely evolution thereof without development as far as natural changes from the baseline scenario can be assessed with reasonable effort, on the basis of the availability of environmental information and scientific knowledge” is included within the Onshore EIA Report.
61. In order to ensure that the Proposed Development is assessed against a realistic baseline scenario, i.e. what the baseline conditions are likely to be once the Proposed Development is operational, a description of the likely future baseline conditions is provided within this section.
62. In the event that the site remained undeveloped, aside from slight variations in populations and distribution of the more mobile species, and variations associated with changes to arable cropping and livestock management, it is considered unlikely that there would be any significant change to the baseline conditions within the Ecology Survey Area.
63. A summary of the relevant climate change projections using the UK Climate Change Projections (Met Office, 2022) is as follows:

• Temperatures are projected to increase, particularly in summer;
• Winter rainfall is projected to increase and summer rainfall is most likely to decrease;
• Heavy rain days (rainfall greater than 25mm) are projected to increase, particularly in winter;
• Near surface wind speeds are expected to increase in the second half of the 21st century with winter months experiencing more significant effects of winds; however, the increase is projected to be modest;
• There will be an increase in the frequency of winter storms; and
• Sea levels are expected to rise by between 8 cm and 90 cm (based on data for Edinburgh) by the end of the century.
  64. The non-avian ecological baseline is unlikely to change significantly over the coming years as a direct result of climate change. Changes to the local climate, such as higher temperatures and reduced rainfall in the summer months, could gradually lead to conditions that today are more typical of locations further south in Great Britain, but in the case of agricultural and wooded habitats, changes to these and their associated species are unlikely to be significant over the lifetime of the Proposed Development. Higher sea levels and severe winter storms could potentially shift the coastline further inland but again this process is unlikely to be significant over the lifetime of the Proposed Development.  
  65. The Habitat Management Plan (to be produced post-consent) will include a planting schedule that contains species that are known to also occur in the south of Great Britain, thus ensuring future resilience against potential climatic change.

7.7.11.              Data Assumptions and Limitations

Extended Phase 1 Habitat Survey

66. The extended Phase 1 habitat survey was undertaken within the optimal survey season from April to September, inclusive, and conditions were suitable for survey. There were some areas of the study area that could not be accessed (e.g. the Viridor site to the west) however due to the nature of the habitats present, it was possible to assess broad habitat types from the site boundary which is considered suitable for assessment. Some targeted updates were made in mid-October but involved habitats that were readily classifiable, as species remained present and identifiable.

Badger Survey

67. The optimal survey period for badgers is spring or autumn when badgers are most active and vegetation has died back allowing field sign to be more visible. The badger survey was carried out in autumn 2020 and 2021 and in spring 2022 when vegetation density was generally low and any field signs, if present, more easy to detect. However, during the 2020 and 2021 surveys, bracken (Pteridium aquilinum) was still high, and areas of dense gorse (Ulex europaeus) were also impassable in some areas of the site, especially around the Thornton Burn and Braidwood Burn, and this may have obscured some badger field signs. The perimeter of any dense stands was therefore walked and mammal paths followed as far as possible to reduce this limitation. Areas apparently suitable for badger setts were noted to ensure that appropriate working methods can be adopted (e.g. supervised vegetation removal) during any site clearance works (as detailed within Volume 4, Appendix 7.2).

Bat Surveys

68. There was no access to private properties to complete detailed Preliminary Roost Assessments. Buildings were therefore assessed from a distance. No buildings with potential roost features were identified within 30 m of the Proposed Development and as such no further survey was required.

Otter and Water Vole

69. Heavy rainfall in October 2020 caused water levels within watercourses to rise and may have washed away otter and water vole evidence at lower levels such as prints and spraint.  Water levels at the time of the survey were not considered to be a limitation and would not have obscured resting sites or burrows.
70. Areas of dense gorse scrub along some of the Thornton Burn and Dry Burn was often found to be impenetrable by surveyors when surveying 20 m from channel. In addition, steep, rocky banks through sections of the Thornton Burn and Braidwood Burn could not be safely accessed to survey. As a result, full assessment for resting sites could not be conducted in some areas of the bankside. These sections are highlighted in Volume 4, Appendix 7.2. and Appendix Figure 7.2.2

Great Crested Newt

71. There was no access to some areas of the great crested newt study area as highlighted in Volume 4, Appendix 7.2, Appendix Figure 7.2.2 Three waterbodies, Pond 3 (177 m north-west of the site), Pond 4 (235 m north-west of the site) and Pond 5 (370 m north-west of the site) could therefore not be assessed for suitability to support great crested newt. The ponds lie outwith 500 m of the main footprint of the Proposed Development. A temporary access road is proposed that lies within 500 m of the ponds, however the proposed route is through an arable field and great crested newt are highly unlikely to be within the footprint of the works. No further survey or mitigation for this species is deemed necessary to that outlined within Volume 4, Appendix 7.4.

7.8. Key Parameters for Assessment

7.8.1.    Maximum Design Scenario

72. The maximum design scenario involves a 40-month construction period, the only permanent habitat loss is the construction of the onshore substation and watercourse crossings.  Even with a 40-month construction period the works within this time period are temporary and localised within the Proposed Development footprint.
73. The maximum design scenario(s) are shown in Table 5.1 of Volume 1, Chapter 5 which have been selected as those having the potential to result in the greatest effect on an identified receptor or receptor group. Effects of greater adverse significance are not predicted to arise should any other development scenario, based on details within the Project Design Envelope (e.g. different infrastructure layout), to that assessed here, be taken forward in the final design scheme.
74. Potential ecology and nature conservation impacts considered within this assessment are the following:

• temporary habitat loss or fragmentation from the maximum temporary infrastructure land take of the Proposed Development;
• permanent habitat loss or fragmentation from the maximum permanent infrastructure land take of the Proposed Development;
• direct or indirect impacts on the qualifying features of designated sites;
• disturbance or direct mortality of protected or notable species due to construction activities; and
• habitat enhancement during operation resulting in beneficial impacts on protected species.

7.8.2.    Impacts Scoped Out of the Assessment

75. As noted in Section 7.6, under evaluation methods for IEFs, ecological features of local or higher value are considered IEF. Due to a range of factors, some of these IEFs can be scoped-out of further consideration if they are not vulnerable to effects from the Proposed Development.

7.8.3.    IEFs Scoped In/Out of the Assessment

76. Following the collation of the baseline data, including desk study and field survey data, and following the embedded mitigation measures described in Section 7.10, several potential effects on ecological features can be scoped out of further assessment, as described in Table 7.15 below. This is based on professional judgement and experience from other relevant projects in the region.
77. The habitats present and their respective areas within the ecology study area are presented in Table 7.11. Estimates of direct and indirect habitat losses from the Proposed Development are presented in Table 7.20   Open ▸ . An estimated total of 58.5 ha will be directly lost due to the Proposed Development, approximately 12.44 % of the ecology study area. This includes 12.9 ha under the permanent footprint of works and 45.6 ha under the temporary footprint of works.
78. As listed in Table 7.15 the assessment of effects will be applied to IEFs that are known to be present within the site or surrounding area (as confirmed through survey results and consultations outlined above) and which could be susceptible to impacts from the Proposed Development.

Table 7.15: IEFs Scoped In or Out of the Assessment

Operational and Maintenance Phase

79. Full details of the operational phase are outlined in Volume 1, Chapter 5 but in summary will involve regular maintenance checks, including annual checks of the cable corridor on foot. Works would only be required in the event of a fault. Should there be a fault within the cable, the area around the fault would be excavated and the fault repaired.
80. The temporary nature of the impacts associated with the onshore aspects of the Proposed Development indicate that any impacts experienced during the operational phase are anticipated to be significantly less severe and shorter in duration and scale than those assessed for the construction phase across all receptors.
81. Given the reduced impacts that are likely during the operational phase of the Proposed Development, it is considered that levels of disturbance that may result from general maintenance are unlikely to be greater than the levels of disturbance that IEFs will be habituated to and are therefore unlikely to generate a significant effect. For this reason potential impacts on IEFs resulting from operational and maintenance activities are not assessed separately in this chapter.

Decommissioning Phase

82. Impacts of decommissioning are also identified and are of a similar nature to construction impacts, although the existing baseline is difficult to define at the end of the 35-year operational lifetime of the Proposed Development. Assuming that the baseline conditions will be broadly similar to the current one described here for construction impacts, then the impacts would be of a similar, but likely reduced, scope. For this reason potential impacts on IEFs resulting from decommissioning activities are not assessed separately in this chapter. Good practice mitigation will be implemented during decommissioning, such as protected species surveys ahead of any ground works.

7.9. Methodology for Assessment of Effects

7.9.1.    Overview

83. The approach to the EcIA follows the Chartered Institute of Ecology and Environmental Management guidelines (CIEEM, 2018), which prescribe an industry-standard method to define, predict and assess potential ecological effects to a given proposed development. Starting with establishing the baseline through a mix of desk study and field survey, important ecological features (the IEFs) are identified and those requiring assessment established through a reasoned process of valuation and consideration of factors, such as statutory requirements, policy objectives for biodiversity, conservation status of the IEF (habitat or species), habitat connectivity and spatial separation from the Proposed Development. From this stage, these features are assessed for impacts with the assumption of this being in the presence of construction industry-standard mitigations to ameliorate impacts as far as practicably possible. Additional mitigation strategies can then be determined to minimise any residual impacts that would otherwise be experienced by the IEF and any opportunities for enhancement identified.
84. In summary, the impact assessment process (CIEEM, 2018) involves:

• Identifying and characterising impacts and their effects;
• Incorporating measures to avoid and mitigate negative effects;
• Assessing the significance of any residual effects after mitigation;
• Identifying the appropriate compensation methods to offset significant residual effects; and
• Identifying opportunities for ecological enhancement.

7.9.2.    Ecological Zone of Influence

85. The Ecological Zone of Influence (EZoI) is defined as the area within which there may be ecological features subject to effects from the Proposed Development. Such effects could be direct (e.g. habitat loss resulting from land-take or removal of a building occupied by bats) or indirect (e.g. noise or visual disturbance causing a species to move out of the EZoI. The EZoI was determined through:

• Review of the existing baseline conditions based on desk study results, field surveys and information supplied by the consultees;
• Identification of sensitivities of ecological features, where known;
• The maximum design scenario(s) of the Proposed Development and approach to construction; and
• Through liaison with other technical specialists involved in the assessment (e.g. hydrologists and noise specialists).

7.9.3.    Characterising Ecological Impacts and Effects

86. In accordance with the CIEEM guidelines, the following definitions are used for the terms ‘impact’ and ‘effect’.

• Impact – Actions resulting in changes to an ecological feature. For example, the construction activities of a development removing a hedgerow; and
• Effect – Outcome to an ecological feature from an impact. For example, the effects on a species population from the loss of a hedgerow.
  87. In accordance with the CIEEM guidelines, when determining impacts on IEFs, reference is made to the following:
• Beneficial or adverse – i.e. whether the impact has a beneficial or adverse effect in terms of nature conservation objectives and policy;
• Magnitude – this refers to size, amount, intensity and volume. It should be quantified if possible and expressed in absolute or relative terms (e.g. the amount of habitat lost, percentage change to habitat area, percentage decline in a species population);
• Extent – i.e. the area over which an impact occurs;
• Duration – i.e. the time for which an impact is expected to last;
• Timing and frequency – i.e. whether impacts occur during critical life stages or seasons; and
• Reversibility – i.e. a permanent impact is one that is irreversible within a reasonable timescale or for which there is no reasonable chance of action being taken to reverse it. A temporary impact is one from which a spontaneous recovery is possible.
  88. Both direct and indirect impacts are considered. Direct ecological impacts are changes that are directly attributable to a defined action (e.g. the physical loss of habitat occupied by a species during the construction process). Indirect ecological impacts are attributable to an action but affect ecological resources through effects on an intermediary ecosystem, process or feature (e.g. fencing of a development site may cause scrub to invade a grassland).
  89. The CIEEM guidelines state that impacts should be quantified, if possible, and expressed in absolute or relative terms (e.g. the amount of habitat lost, percentage change to habitat area, percentage decline in a species population). That approach has been followed here, where possible. For the purposes of this assessment, the predicted impacts on an ecological feature are categorised as ‘no impact’, ‘negligible’, ‘low’, ‘medium’ or ‘high’, based on the definitions in Table 7.16.

 Table 7.16: Level of Impact Magnitude