6. EIA Methodology

6.1. Introduction

  1. This chapter of the Array Environmental Impact Assessment (EIA) Report presents the EIA methodology used for the assessment of likely significant environmental effects of the Ossian Array infrastructure (hereafter the ‘Array’) on physical, biological and human environment receptors.
  2. This Array EIA Report has been developed to support an application for consent for the Array under Section 36 of the Electricity Act 1989 and relevant Marine Licences (under the provisions of Part 4 of the Marine and Coastal Access Act 2009 for United Kingdom (UK) waters beyond 12 nm) and in accordance with the requirements of the following regulations (collectively referred to hereafter as the EIA Regulations):
  • in respect of a Section 36 consent application: The Electricity Works (Environmental Impact Assessment) (Scotland) Regulations 2017; and
  • in respect of a marine licence application: The Marine Works (Environmental Impact Assessment) Regulations 2007.
  1. As explained in volume 1, chapter 1, this EIA Report has been prepared for the Array only; the Proposed offshore export cable corridor(s) and Proposed onshore transmission infrastructure (comprising the Proposed onshore export cable corridor(s) and Proposed onshore converter station(s)) and the Proposed landfall location(s)) associated with the Array will be subject to a separate EIA Scoping Report(s), EIA Report(s) and consent applications(s). While these other elements of Ossian do not form a part of this application or the project-alone assessment in this Array EIA Report, they are included in the Cumulative Effects Assessment (CEA) for the Array.
  2. This chapter presents:
  • the assessment methodology used to determine potential impact including the approach that has been used to assess magnitude, sensitivity of receptors and reach a conclusion on the likely significance of effect;
  • the methodology used for Cumulative Effects Assessment (CEA);
  • the methodology for assessing inter-related effects; and
  • the methodology for assessing transboundary effects.
  1. Each topic chapter also contains further-topic specific methodologies where appropriate. These are explained further within the relevant Array EIA Report chapters (volume 2, chapters 7 to 20).

6.2. Environmental Impact Assessment Legislation and Guidance

  1. In compliance with the European Union (EU) Directive on the assessment of the effects of certain public and private projects on the environment (EIA Directive) (2011/92/EU, as amended by Directive 2014/52/EU) and the EIA Regulations, when applying for Section 36 consent or a marine licence, an EIA Report is required to be prepared and submitted to support these applications if the Array is likely to have a significant effect on the environment due to factors such as its size, nature or location.
  2. The assessment of effects methodology employed in this Array EIA Report draws upon relevant legislation, policy and guidance, including those listed below:
  • Council Directive 2011/92/EU of 13 December 2011 on the assessment of the effects of certain public and private projects on the environment, as amended by Council Directive 2014/52/EU (the EIA Directive);
  • The Electricity Works (Environmental Impact Assessment) (Scotland) Regulations 2017;
  • The Marine Works (Environmental Impact Assessment) Regulations 2007;
  • The Conservation of Habitats and Species Regulations 2017 – only applies in Scotland for specific activities including consent applications under Sections 36 and 37 of the Electricity Act 1989;
  • The Conservation of Offshore Marine Habitats and Species Regulations 2017 – applies to the Scottish offshore region (beyond 12 nm);
  • The Wildlife and Countryside Act 1981;
  • Marine Scotland Consenting and Licensing Guidance: For Offshore Wind, Wave and Tidal Energy Applications (Marine Scotland, 2018);
  • Guidelines for Ecological Impact Assessment (EcIA) in the UK and Ireland – Terrestrial, Freshwater, Coastal and Marine (Chartered Institute of Ecology and Environmental Management (CIEEM), 2019;
  • A Handbook on Environmental Impact Assessment: Guidance for Competent Authorities, Consultees and Others Involved in the Environmental Impact Assessment Process in Scotland (NatureScot, 2018);
  • Environmental Impact Assessment for Offshore Renewable Energy Projects (British Standards Institute (BSI), 2015);
  • Guidelines for data acquisition to support marine environmental assessments of offshore renewable energy projects (Centre for Environment, Fisheries and Aquaculture Science (Cefas), 2012);
  • A Review of Assessment Methodologies for Offshore Wind Farms (Collaborative Offshore Wind Research into The Environment (COWRIE) METH-08-08) (Maclean et al., 2009);
  • Institute of Environmental Management and Assessment (IEMA) Environmental Impact Assessment Guide to Delivering Quality Development (IEMA, 2016);
  • UK Planning Inspectorate Advice Note Nine: Rochdale Envelope (PINS, 2018);
  • UK Planning Inspectorate Advice Note Twelve: Transboundary Impacts (PINS, 2020);
  • UK Planning Inspectorate Advice Note Seventeen: Cumulative Effects Assessment (PINS, 2019);
  • The Conservation of Habitats and Species (Amendment) (EU Exit) Regulations 2019 (HM Government, 2019a);
  • Planning Advice Note (PAN) 1/2013 Environmental Impact Assessment (Scottish Government, 2013);
  • Cumulative Impact Assessment Guidelines – Guiding Principles for Cumulative Impact Assessment in Offshore Wind Farms (RenewableUK, 2013);.and
  • IEMA Guide to Determining Significant for Human Health In Environmental Impact Assessment (IEMA, 2022).
  1. Topic-specific guidance and legislation, where appropriate, is discussed within the relevant Array EIA Report chapters (volume 2, chapters 7 to 20).
  2. References to legislation in this Array EIA Report are to the relevant legislation as amended.

6.3. Consultation

  1. Consultation on the Array EIA methodology (including the CEA methodology and approach to assessing transboundary and inter-related effects) was undertaken at the Array EIA scoping stage. The Ossian Array EIA Scoping Report (Ossian OWFL, 2023) presented these methodologies and requested feedback on the proposed approaches. Additional post-scoping consultation relating to methodology was sought on specific technical topics which is discussed in the technical chapters (volume 2, chapters 7 to 20). A summary of the key issues raised during consultation relating to this chapter are outlined below in Table 6.1   Open ▸ together with how these issues have been considered in the production of this chapter.

Table 6.1:
Summary of Key Consultation Issues Raised relevant to the EIA Methodology (Marine Directorate – Licensing Operations Team (MD-LOT), 2023)

Table 6.1: Summary of Key Consultation Issues Raised relevant to the EIA Methodology (Marine Directorate – Licensing Operations Team (MD-LOT), 2023)

  1. In addition to this, the Applicant has carried out several public consultation events. A summary of these events can be found in Table 6.2   Open ▸ .

 

Table 6.2:
Public Consultation Events

Table 6.2: Public Consultation Events