5.             Offshore Physical Environment

5.1.        Physical Processes

5.1.1.    Introduction

206. This section of the Offshore EIA Scoping Report identifies the elements of the physical processes of relevance to the Proposed Development and considers the potential impacts from the construction, operation and maintenance, and decommissioning of the offshore and intertidal components (seaward of the MHWS mark) of the Proposed Development on physical processes.
207. Physical processes were included in the initial Offshore EIA Scoping Report. Although the change in project scope applied to this Offshore EIA Scoping Report, which is combining the offshore Proposed Development Array Areas, the impacts are anticipated to generally be the same as identified in the initial Scoping Report. The initial Berwick Bank Wind Farm Proposal Scoping Opinion response has been considered for the development of this section. Additional impacts have been scoped in including coastal recession and scour protection. The assessment will also consider potential impacts (direct and indirect) on the Firth of Forth Banks Complex nature conservation Marine Protected Area (ncMPA).
208. For the purposes of this Offshore EIA Scoping Report and subsequent Offshore EIAR, physical processes are defined as encompassing the following elements:

• tidal elevations and currents;
• waves;
• bathymetry;
• geology and seabed sediments;
• suspended sediments; and
• sediment transport.
  209. The parameters listed above are collectively referred to as ‘physical processes’ through the remainder of this Offshore EIA Scoping Report.

5.1.2.    Study Area

210. The physical processes study area for the Proposed Development is illustrated in Figure 5.1  Open ▸ and defined as the:

• Proposed Development Array Area;
• proposed ECC;
• landfall area; and
• seabed and coastal areas that may be influenced by changes to physical processes due to the Proposed Development, based on the outputs of the physical processes modelling which will encompass a wider domain including the Firth of Forth Banks Nature Conservation MPA (ncMPA).

5.1.3.    Baseline Environment

211. This section provides a concise summary of the baseline environment of the Proposed Development, reference should be made to Appendix 5  Open where a more detailed description is provided. This baseline is based on a review of bathymetry, tidal regime, meteorological information, wave climate and seabed sediments from both desktop study/reports and site survey data (as per Appendix 5  Open ), including:

• bathymetric data in order to determine site topography, gradients and a baseline for a seabed mobility study that may influence foundation design and cable installation using multibeam echo sounder (MBES);
• high-resolution sidescan sonar (SSS) data to determine seabed features and the presence of boulders, seabed sediments and debris;
• high-resolution sub-bottom profiler (SBP) data to determine the shallow sub-surface soil conditions that may influence foundation design and cable installation such as boulders and shallow geology features;
• multichannel 2D ultra-high resolution seismic (UHRS) data to foundation depth to determine the deeper sub-surface soil conditions; and
• magnetometer data across the site (along the planned survey lines) to support unexploded ordnance (UXO) risk reduction.

Bathymetry

212. The bathymetry of the Proposed Development Array Area is influenced by the presence of large-scale morphological bank features, including the Marr Bank and the northern extent of the Berwick Bank. Geophysical data collected in August to October 2019 suggests the water depth within the Proposed Development Array Area varies between 32.8 m and 68.5 m relative to LAT, and average depths of generally 51 m below LAT. Minimum water depths of approximately 38 m below LAT are found on top of the western central part of the Proposed Development Array Area and maximum depth around 68 m below LAT in the east of the banks.
213. The bathymetry of the proposed ECC is relatively variable, between 20 m and 69 m below LAT at the time of geophysical investigation, as shown in Apx. Figure 6. 1  Open ▸ and Apx. Figure 6. 2  Open ▸ .

Wind And Waves

214. Metocean surveys conducted across the former Firth of Forth Zone to characterise the zone provide an overview of the wave regime within the physical processes study area. During the stormiest event over the 18-month wave buoy deployment, a significant wave height of 6.7 m was recorded in January 2012, which correlated with a 1 in 1-year sea wave climate return period event (Fugro, 2012).
215. Within the Offshore EIAR physical processes baseline assessment, a detailed baseline will be presented which provides an overview of the wind and wave regime within the region and specific to the Proposed Development, utilising data collected from deployed wave buoys.

Tidal Currents And Elevation

216. Metocean surveys conducted across the former Firth of Forth provided an overview of the tidal current flows. The strongest current flows during the survey period were recorded at the two most northerly sites which correlate to the location of Seagreen Alpha/Bravo. At these sites, a maximum current of 0.91 metres per second (m/s) was recorded in April 2011 during a period of spring tides that correlated with the maximum water level at most sites. Current speeds decreased slightly at the other sites with maxima ranging from 0.68 m/s to 0.77 m/s (Fugro, 2012). Further detail is provided in Apx. Table 6. 2  Open ▸ .

Figure 5.1: Physical Processes Study Area

Geology

Proposed Development Array Area

217. The Proposed Development Array Area is part of a dynamic landscape where quaternary and pre-quaternary formations have been shaped as erosional surfaces by different geomorphic factors and continue to be shaped and modelled by the present day offshore marine conditions (Fugro, 2020a). The morphology features are present due to advances and rapid retreats consistent with an oscillating and dynamic ice margin during British Ice Sheet (BIS) deglaciation (Graham et al., 2009).
218. Subsequent sea level rise without new sediments led to the deepening and eroding of the sea mounds and banks present in the area. Seabed bottom currents have been actively mobilising and redistributing surficial sediments, developing bedforms and filling up both depressions and channels.
219. The seafloor morphology within the Proposed Development Array Area is very varied and can be classified into four types of morphological features (Figure 5.2  Open ▸ ):

• large scale banks (the Marr Bank and the Berwick Bank);
• arcuate ridges;
• incised valleys, relic glacial lakes and channels; and
• bedforms.
  220. The majority of the Proposed Development Array Area seabed is ‘featureless’ however the southern and north-western extent of the Proposed Development Array Area are dominated by megaripples, sandwaves, ribbons and bars. Boulders are also prevalent across the area and are either represented as isolated boulders or as clusters.

Proposed ECC

221. The seabed within the proposed ECC is variable, with morphological features which are framed by relic pre-Holocenic landscape, and secondary morphological features characterised by bedforms and boulder fields formed by reworked and redeposition of available material in present-day shallow marine conditions.
222. The geophysical surveys observed that the bedforms in the proposed ECC are comprised of principally flow-transverse structures (subaqueous dunes: ripples, megaripples); locally the bedforms can be linear, braided and lobe-shaped (bars and ribbons). The seabed within the proposed ECC can be classified into several types of morphological features (Figure 5.2  Open ▸ ), which include:

• primary morphological features:
• outcrops and erosional surfaces and platforms;
• ridges; and
• high topographic mounds and incised valleys and channels.
• secondary morphological features:
• subaqueous dunes;
• irregularity of the seafloor;
• features related to anthropogenic activity; and
• boulder fields.

Seabed Substrate

223. A summary of the surficial sediment geology and the seabed features is presented in this section, based on interpretation undertaken of the SSS data collected during site-specific geophysical surveys. Figure 5.3  Open ▸ illustrates the sediment interpretation from Side Scan Sonar (SSS) data collected across the Proposed Development.

Proposed Development Array Area

224. The geophysical survey (August to October 2019) of the Proposed Development Array Area identified that it is comprised of several distinctive features:

• boulders and boulder fields;
• areas of ripples;
• areas of megaripples and sand waves; and
• areas of trawl marks.
  225. The majority of the Proposed Development Array Area seabed is ‘featureless’ however the southern and north-western extent of the Proposed Development Array Area are dominated by megaripples, sandwaves, ribbons and bars. Boulders are also prevalent across the area and are either represented as isolated boulders or as clusters.
  226. Seabed sediments present in the Proposed Development Array Area can be classified into several groups (as per Figure 5.3  Open ▸ ):
• coarse gravel, shelly gravelly sand with boulders;
• mixed sediment;
• mixed sediments with patchy coarse material or boulders; and
• muddy sand.

Figure 5.2:  Proposed Development Array Area and Proposed ECC Seabed Features Data

Figure 5.3: Sediment Interpretation from Side Scan Sonar (SSS) Data for the Proposed Development Array Area and Proposed ECC

Proposed ECC

227. The proposed ECC is comprised of several distinctive features (Figure 5.2  Open ▸ ):

• boulders and boulder fields;
• area of ripples;
• area of megaripples and sand waves; and
• area of trawl marks.
  228. The seabed within the proposed ECC was recorded as smooth with very few observed primary morphological features (such as high reliefs or ridges), while secondary morphological features such as ripples and megaripples, sand bars and ribbons characterise the seabed morphology.
  229. Seabed sediments present in the proposed ECC can be classified into several groups:
• hard substrate: coarse sediment with cobbles, boulders and rock outcropping or sub outcropping characterised by high reflectivity signature in the sidescan data;
• gravelly sand and coarse sediments with medium reflectivity; and
• sandy sediments including fine sand and muddy sand with low reflectivity.
  230. The nearshore area where the proposed ECC makes landfall contains seabed features such as an area of ripples in the nearshore and a generally featureless seabed with intense fishing trawl marks in the area of the proposed ECC and seaward of this area.

Landfall

231. SSER is currently assessing the feasibility of both landfall locations on the East Lothian coast, Thorntonloch Landfall and Skateraw Landfall (as shown in Figure 1.1  Open ▸ ), one will be selected. The geophysical surveys provided an overview of the Thorntonloch landfall area, identifying a band of approximately 2 km along the shore to be defined as the coastal area. This coastal area is comprised of a sandy beach to the north, a rocky platform in the middle and a pebble and rocky beach in the south. The nearshore area of the proposed ECC consists of a submerged beach and the rocky platform from the lowest tide until around 30 metres depth, approximately 2 miles from the shore.

Suspended Sediment

232. As discussed further within Appendix 5  Open , sampling was conducted at an offshore station within Seagreen Alpha/Bravo in March and June 2011, suggesting total suspended solids (TSS) to be low. The samples collected illustrated a TSS of < 5 mg/l with a maximum reading of 10 mg/l during March 2011 (Fugro, 2012). Although all values are low, a slight increase in TSS was observed in March.
233. The Cefas Climatology Report 2016 (Cefas, 2016) provides the spatial distribution of average non-algal Suspended Particulate Matter (SPM) for the UK continental shelf (UKCS). This study suggests the SPM in the vicinity of the Proposed Development is estimated as approximately 0 mg/l to 1 mg/l over the 1998 to 2005 period. Higher levels of SPM are experienced in the winter months; however, due to the tidal influence, even during summer months the levels remain elevated.

5.1.4.    Potential Proposed Development Impacts

234. A range of potential impacts on physical processes have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures:

• Construction

–           Increase in suspended sediments and the potential impact to physical features within the Proposed Development Array Area. Increase in suspended sediments due construction related activities such as possible seabed preparation activities if required, wind turbine foundation installation or array cable installation and the potential impact to physical features within the Proposed Development Array Area;

–           Impacts to hydrodynamics, sediment transport and beach morphology due to cable installation activities and potential impact to physical features at landfall.

• Operation and Maintenance

–           Impacts to the wave regime and the associated potential impacts along adjacent shorelines;

–           Impacts to tidal regime and associated potential impacts to physical features and morphology (e.g. bank morphology).

–           Impacts to sediment transport and sediment transport pathways due to presence of infrastructure in the physical processes study area and associated potential impacts to physical features and morphology (e.g. bank morphology);

–           Impacts to beach morphology, hydrodynamics and sediment transport (littoral drift) due to operation and maintenance activities and potential impact to physical features at landfall;

–           Increase in suspended sediments due to operation and maintenance related activities such as cable repairs, and the potential impact to physical features within the Proposed Development Array Area;

–           Increase in suspended sediments due to operation and maintenance related activities such as cable repairs, and the potential impact to physical features within the proposed ECC; and

–           Scour of seabed sediments.

• Decommissioning

–           Increase in suspended sediments due to decommissioning related activities such as cable repairs, and the potential impact to physical features within the Proposed Development Array Area;

–           Increase in suspended sediments due to decommissioning related activities such as cable repairs, and the potential impact to physical features within the proposed ECC; and

–           Impacts to hydrodynamics, sediment transport and beach morphology due to decommissioning activities and potential impact to physical features at landfall.

5.1.5.    Designed in Measures

235. The following designed in measures, and how these can reduce potential for impact have been considered in the identification of potential impacts that have been scoped into (and out) of further assessment for the Proposed Development assessment (section 5.1.6, Table 5.1  Open ▸ ):

• scour protection: The use of scour protection around offshore structures and foundations will be employed, as described in section 2  Open ▸ ; and
• suitable implementation of monitoring of cable protection through the Operation and Maintenance phase of the Proposed Development; and
• adherence to a Cable Plan (CaP).
  236. Any further mitigation requirements to be adopt for physical processes will be dependent on the significance of the effects and will be consulted upon with statutory consultees throughout the EIA process.

5.1.6.    Potential Impacts after the Implementation of designed in Measures

237. A range of potential impacts on physical processes have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development. The impacts that have been scoped into the Proposed Development assessment are outlined in Table 5.1  Open ▸ together with a description of any additional data collection (e.g. site-specific surveys) and/or supporting analyses (e.g. modelling) that will be required to enable a full assessment of the impacts.
238. At this stage, no potential impacts have been scoped out of the assessment.

 

Table 5.1: Impacts Proposed to be Scoped In to the Proposed Development Assessment for Physical Processes. Project phase refers to construction (C), operation and maintenance (O) and decommissioning (D) phase of the Proposed Development

 

 

5.1.7.    Proposed Approach to the Environmental Impact Assessment

239. The physical processes EIA will follow the methodology set out in section 4  Open ▸ . Specific to the physical processes EIA, the following guidance documents will also be considered:

• Coastal Process Modelling for Offshore Wind farm Environmental Impact Assessment: Best Practice Guide. (COWRIE, 2009); and
• Guidelines in the use of metocean data through the lifecycle of a marine renewables development (ABPmer et al., 2008).
  240. To support the development of the physical processes EIA, a numerical modelling study is planned. This model will be used to assess the magnitude and significance of changes to several processes, including:
• tidal currents;
• wave climate;
• littoral currents;
• sediment transport; and
• SSCs.
  241. This study will be undertaken using the MIKE software developed by DHI (www.dhigroup.com), which contains a suite of coastal and environmental modelling modules of global standard. The key to the MIKE suite of computational models is that each module may be applied to a single model mesh and then the modelling of combined (coupled) parameters may be undertaken.
  242. The MIKE 21 Flexible Mesh (fm) coupled modules would be used to model baseline wave climate, tidal flows and sediment transport, using a model which, whilst providing sufficient detail to simulate the necessary parameters, is also computationally efficient by utilising a flexible mesh comprised of the most up-to-date bathymetric data. The computational model applied in the baseline study will be amended to include the impact of the wind turbine and offshore platform structures with associated scour and cable protection to quantify the change in sediment transport and wave climate. Similarly, sediment will be released into the water column to replicate the construction phase works during the installation of the inter-array and offshore export cabling and the sediment dispersion and fate will be gauged. This also extends to the material released into the water column from the cable laying. There will be three plume models developed for the foundation installation, three plume models associated with cable installation (one for inter-array & two for offshore/landfall options). Modelling will be validated using all available data sources, including SS sampling undertaken at Seagreen Alpha/Bravo – extending to include wave climate and tidal currents for which monitoring has been undertaken.
  243. The computational modelling will quantify the potential impacts of the installation (including seabed preparation activities) and ongoing operational effects on the tide, wave and sediment transport processes. It will also provide the transport and fate of any material released into the water column as part of the installation works.
  244. The results of this numerical modelling will be used to support the impact assessments within the below topics:
• benthic subtidal and intertidal ecology (section 6.1  Open ▸ );
• fish and shellfish ecology (section 6.2  Open ▸ );
• marine mammals (section 6.3  Open ▸ );
• marine archaeology and ordnance (section 7.4  Open ▸ ); and
• infrastructure and other users (section 7.7  Open ▸ ).

Potential Cumulative Effects

245. Although the predicted effects from the Proposed Development on benthic subtidal and intertidal ecology are considered to be localised to within the footprint of the Proposed Development, there is potential for the predicted impacts to interact with impacts from other projects and activities in the regional benthic subtidal and intertidal ecology study area and lead to a cumulative effect on receptors. The cumulative effects assessment will follow the approach outlined in section 4.3.7.

Potential Transboundary Impacts

246. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open . No potential transboundary effects have been identified for physical processes and therefore this will not be considered within the EIAR.

5.1.8.    Scoping Questions to Consultees

• Do you agree with the data sources which are suggested for the assessment of physical processes?
• Do you agree that all receptors and impacts have been identified for physical processes?
• Do you agree with the suggested designed in measures and is this mitigation appropriate?
• Do you agree with the proposed approach assessment?
• Do you agree that transboundary impacts of marine physical processes receptors should be scoped out of the Proposed Development EIA?
• Do you agreement with approach to transboundary assessment?

5.1.9.    Next Steps

247. This section provides a summary of proposed topic specific next steps as summarised below:

• Define the baseline environment and assessment approach:

–           Present evidence base, baseline characterisation (including coastal processes) to stakeholders and agree on impacts and receptors to be scoped in/out of EIA Report.

• Assessment of Physical Processes potential impacts through the EIA Report process:

–           Present Maximum Design Scenarios and impact assessment approach including sensitivity of receptors, method of quantifying impacts and approach to hydrodynamic and hydro-sedimentary modelling to stakeholders; and

–           Discuss initial findings of impact assessment, appropriate mitigation and monitoring with stakeholders.

248. The above steps will be undertaken through the Benthic Ecology, Fish and Shellfish and Physical Processes Road Map.

 

5.2.        Subsea Noise

5.2.1.    Introduction

249. This section of the Offshore EIA Scoping Report identifies the elements of subsea noise of relevance to the Proposed Development and considers the potential impacts from the construction, operation and maintenance, and decommissioning of the offshore and intertidal components (seaward of the MHWS) of the Proposed Development with respect to subsea noise.
250. Subsea noise was included in the initial Offshore EIA Scoping Report. Although the change in project scope applied to this Offshore EIA Scoping Report, which is combining the offshore Proposed Development Array Areas, the impacts are anticipated to generally be the same as identified in the initial Scoping Report. The initial Berwick Bank Proposal Scoping Opinion response has been considered for the development of this section.
251. The subsea noise study will provide an assessment of the level of subsea noise generated from the Proposed Development and will be provided as a technical appendix to the Offshore EIAR.
252. It will be used to inform impact assessment for the following receptor groups:

• Fish and Shellfish Ecology;
• Marine Mammals;
• Commercial Fisheries; and
• Infrastructure and Other Users.

5.2.2.    Study Area

253. No separate study area has been outlined for subsea noise as this is defined by the receptors and discussed within relevant sections listed above.

5.2.3.    Baseline Environment

Desktop Study

254. An initial desk-based review of literature and data sources to support this Offshore EIA Scoping Report has identified a number of baseline datasets in the form of both pre-existing specific datasets. A subsea noise assessment was completed for the application of Seagreen Alpha/Bravo, and these assessments shall be reviewed and used, where applicable, to inform the subsea noise assessment and modelling strategy for the Proposed Development. Key desktop data reports are summarised in Table 5.2  Open ▸ .

 

Table 5.2: Summary of Key Desktop Reports

 

Baseline Characterisation

255. Background or “ambient” subsea noise is created by several natural sources, such as rain, breaking waves, wind at the surface, seismic noise, biological noise and thermal noise. Biological sources include marine mammals (using sound to communicate, build up an image of their environment and detect prey and predators) as well as certain fish and shrimp. Anthropogenic sources of noise in the marine environment include fishing boats, ships, industrial noise, seismic surveys and leisure activities, all of which add to ambient background noise. Anthropogenic noise within the vicinity of the Proposed Development will arise primarily from shipping and to a lesser extent, the oil and gas industry. Shipping routes and shipping traffic is discussed in section 7.2  Open ▸ .
256. Research relating to both physiological effects and behavioural disturbance of noise on marine receptors is typically based on determining the absolute noise level for the onset of that effect. Consequently, the criteria for assessing the effects of noise on marine mammals, fish and shellfish, tend to be based on the absolute noise criteria, rather than the difference between the baseline noise level and the noise being assessed (Southall et al., 2007). However, the value of establishing the precise baseline noise level is somewhat diminished due to the lack of evidence-based studies on the effects of noise relative to background on marine receptors.
257. It is important to understand that baseline noise levels will vary significantly depending on multiple factors, such as seasonal variations and different sea states. Therefore, there is very limited value in establishing such values. However, when undertaking an appraisal of underwater noise, it can be helpful to understand the range of noise levels likely to be prevailing within an area so any noise predictions can be placed in the context of the baseline.
258. Further, it is important to note the lack of scientific understanding with regard to how various species distinguish anthropogenic sound relative to masking noise. Therefore, it is necessary to exercise considerable caution if attempting any comparison between subsea noise from the Proposed Development and the baseline noise level.
259. Consequently, no site-specific surveys have been undertaken to inform this Offshore EIA Scoping Report for subsea noise and, at this stage, new or additional baseline surveys are unlikely to be required and are not proposed for the Offshore EIAR.

5.2.4.    Potential Proposed Development Impacts

260. A range of potential impacts on subsea noise have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures:

• Construction

–           Effects of subsea noise on marine life due to use of geophysical survey equipment;

–           Effects of subsea noise on marine life due to construction, operation and maintenance and decommissioning vessels and rigs; and

–           Effects of subsea noise on marine life due to impact driven and drilled pile installation for the WTG and OSP foundations.

• Operation and Maintenance

–           Effects of subsea noise on marine life due to construction, operation and maintenance and decommissioning vessels and rigs; and

–           Effects of subsea noise on marine life due to operational noise from the wind turbines.

• Decommissioning

–           Effects of subsea noise on marine life due to construction, operation and maintenance and decommissioning vessels and rigs; and

–           Effects of subsea noise on marine life due to jacket cutting and removal.

5.2.5.    Designed in Measures

261. Measures adopted as part of the Proposed Development will be discussed within each of the relevant sections of the Offshore EIA Scoping Report for which subsea noise is considered relevant. Each of the proposed mitigation measures relating to reducing potential impacts on receptors from subsea noise will be modelled to assess their efficacy in a quantitative way. The requirement and feasibility of additional measures will be dependent on the significance of the effects of subsea noise on the receptors associated with each topic and will be consulted upon with statutory consultees throughout the EIA process. Any approach to noise mitigation will be informed by best available evidence, including any outputs from work undertaken during construction of the Moray Firth and Forth and Tay area Wind Farms, or any available evidence from Wind Farm Projects in English waters.

5.2.6.    Potential Impacts after the Implementation of designed in measures

262. Throughout the construction, operation and maintenance and decommissioning phases of the Proposed Development, there is the potential for subsea noise to impact sensitive ecological receptors. The potential effects on these receptors will be assessed within the relevant technical sections of the Offshore EIAR (marine mammals, fish and shellfish, commercial fisheries and infrastructure and other users).
263. Impacts that have been scoped into the Proposed Development assessment are outlined in Table 5.3  Open ▸ together with a description of any additional data collection (e.g. site-specific surveys) and/or supporting analyses (e.g. modelling) that will be required to enable a full assessment of the impacts. No potential impacts relating to subsea noise have been scoped out of the assessment.

 

 

 

Table 5.3: Impacts Proposed to be Scoped In to the Proposed Development Assessment for Subsea Noise. Project phase refers to construction (C), operation and maintenance (O) and decommissioning (D) phase of the Proposed Development

 

 

5.2.7.    Proposed Approach to the Environmental Impact Assessment

264. The subsea noise EIA will follow the methodology set out in section 4  Open ▸ . Specific to the subsea noise assessment, the following guidance documents will also be considered:

• good practice guide to underwater noise measurement (NPL, 2014);
• NOAA technical guidance for assessing the effects of anthropogenic sound on marine mammal hearing: Underwater acoustic thresholds for onset of permanent and temporary threshold shifts (NMFS, 2018);
• Marine mammal noise exposure criteria: Updated scientific recommendations for residual hearing effects (Southall et al., 2019);
• Sound exposure guidelines for Fishes and Sea Turtles (Popper et al., 2014);
• The European Union (EU) Marine Strategy Framework Directive (Directive 2008/56/EC). This seeks to achieve good environmental status (GES) in Europe’s seas by 2020. The qualitative descriptors for determining GES include "Introduction of energy, including underwater noise, is at levels that do not adversely affect the marine environment." This Directive was transposed into UK law by the Marine Strategy Regulations 2010; and
• NPS EN-1 Section 5.11, noise and vibration (DECC, 2011).
  265. The impact criteria will be based on the most recent and up-to-date scientific research and guidance, while utilising a precautionary approach. Potential impacts arising from subsea noise on marine mammals and fish will be assessed with respect to the potential for injury and behavioural disturbance. Where possible, noise source data will be based on measured data from similar wind turbine devices. Source noise levels will be based on a combination of theoretical and empirical predictions and scaling of existing data where applicable. The associated source levels of other types of subsea noise associated with the Proposed Development will be based on published data and established prediction methodologies.
  266. Subsea noise modelling is planned to assess the impact of construction and operational noise using a robust, peer reviewed model. In accordance with National Physical Laboratory guidance (NPL, 2014), the choice of model will depend upon many factors which will be determined during the consultation period and will depend on site-specific circumstances (such as bathymetry etc.). However, the chosen model will be appropriate and peer reviewed, such as the energy flux model (Weston, 1976). Such models have been successfully benchmarked against other sound propagation models (e.g. Etter, 2018; Toso et al., 2014; Schulkin and Mercer, 1985) and have been used previously in underwater noise assessments for offshore wind and tidal energy developments as well as for oil and gas and port developments.
  267. The exact scope, specification and methodology of the noise propagation modelling will be discussed and agreed with SNCBs. However, on the basis of previous subsea noise modelling completed for Seagreen Project Alpha and Bravo, the assessment will consider the bathymetry and other characteristics of the area, including the geo-acoustic properties of the seabed. The model will also estimate the unweighted and hearing group weighted Sound Exposure Level (SEL), rms (T90) sound pressure level and peak / peak-to-peak pressure level parameters as recommended by Southall et al., 2019, NMFS 2018, Southall et al., 2007, Acoustic Society of America (ASA) Sound Exposure Guidelines for Fishes and Sea Turtles (Popper et al., 2014) and other guidance. The model will also incorporate swim speeds of marine mammals and fish to calculate cumulative sound exposure levels (SELs).
  268. The cumulative effect of multiple events/operations will also be assessed/modelled and will consider the likely exposure times of species, allowing for safe distances and reaction ranges to be determined. Modelling scenarios will be undertaken for concurrent piling scenarios, and will model piling at up to two locations (for two concurrent piling events) including both typical (most likely) and maximum piling parameters within the PDE. Further, modelling will be undertaking with the consideration of ADDs and also without ADD to provide an overview of both scenarios.
  269. The potential effects of particle motion on marine life will also be considered. This will include a review of the most recent research and published literature and a qualitative or empirical assessment of the potential effects will be undertaken. This assessment will be used to inform the fish and shellfish ecology assessment (including benthic invertebrates).
  270. The results of the noise modelling will be presented in a Subsea Noise Technical Report.

Potential Cumulative Effects

271. Consideration shall be given to cumulative effects from subsea noise in particular during construction related piling activities. The potential for cumulative impacts with other offshore wind farm developments will be considered in the relevant topic receptors sections of the EIA Report. A detailed assessment of the wind farm developments within the area and their construction windows will be required for the Offshore EIAR, to identify which other wind farm developments will be considered in terms of the cumulative underwater noise assessment.

Potential Transboundary Impacts

272. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open . No potential transboundary effects have been identified for subsea noise and therefore this will not be considered within the EIAR.

5.2.8.    Scoping Questions to Consultees

• Do you consider any particular sources or receptors should be included within the noise modelling assessment which have otherwise not been considered?

5.2.9.    Next Steps

273. The over-arching next steps are outlined in section 4.3.4. The approach to subsea noise modelling will be discussed as part of the Marine Mammal Road Map process.

 

5.3.        Airborne Noise

5.3.1.    Introduction

274. This section of the Offshore EIA Scoping Report identifies the elements of offshore airborne noise (seaward of MHWS) of relevance to the Proposed Development and considers the potential impacts from the construction, operation and maintenance, and decommissioning of the offshore and intertidal components (seaward of MHWS) of the Proposed Development on airborne noise on all receptors, onshore and offshore.
275. Airborne noise was included in the initial Offshore EIA Scoping Report. Although the change in project scope applied to this Offshore EIA Scoping Report, which is combining the offshore Proposed Development Array Areas, the impacts are anticipated to generally be the same as identified in the initial Scoping Report. The initial Berwick Bank Proposal Scoping Opinion response has been considered for the development of this section. SSER intends to scope out airborne noise as per agreement on the initial Berwick Bank Wind Farm Scoping Opinion.

5.3.2.    Study Area

276. The airborne noise study area associated with the potential effects resulting from construction and decommissioning activities on onshore receptors is a 2 km buffer around the landfall locations and 4 km buffer around the proposed offshore ECC. Significant noise and vibration effects are not expected beyond this distance. For construction-related vibration, the study area is a buffer of up to 100 m from any vibration-generating construction activity.
277. The airborne noise study areas have been developed to reflect receptors’ increased sensitivity to noise at night, where night-time noise effects from construction and operation are possible.
278. The proposed airborne noise study areas are shown in Figure 5.4  Open ▸ . The airborne noise study area will be reviewed and amended as the proposed offshore ECC is refined through the EIA process.

5.3.3.    Baseline Environment

Desktop Study

279. An initial desk-based review of literature and data sources to support this Offshore EIA Scoping Report has identified a desktop report which is summarised in Table 5.4  Open ▸ below.

 

Table 5.4: Summary of Key Desktop Reports to inform Offshore Airborne Noise Scoping Assessment

 

Site-specific Survey Data

280. No site-specific surveys have been undertaken to inform the Offshore EIA Scoping Report for ambient noise seaward of MLWS. This is because there is sufficient information on the baseline environment to support the decision of scoping out offshore airborne noise from the EIA.
281. Landward of MLWS, baseline survey measurements will be conducted in accordance with current guidance including BS 4142:2014+A1:2019 Method for rating and assessing industrial and commercial sound, and BS 7445-2:1991 Description and measurement of environmental noise (BSI, 2003).

Baseline Characterisation

Seaward of MLWS

282. The Proposed Development Array Area is located approximately 33.5 km offshore, with proposed landfall locations at Thorntonloch and Skateraw near Torness, on the East Lothian coast. The sensitive receptors to offshore airborne noise are likely to be:

• closest offshore oil and gas accommodation, and manned working platforms (32 km from the Proposed Development (Booster Platform 36/22A Norpipe A.S);
• commercial shipping routes;
• fishing vessels (50 m operation / 500 m construction from each wind turbine); and
• nearshore leisure and recreational users including recreational fishing; motor cruising; water sports and scuba diving.

Landward of MLWS

283. The baseline environment within the airborne noise study area is mainly rural with occasional residential properties and industrial sites. Noise in this area is likely to be dominated by road traffic on the A1, rail traffic on the East Coast Main Line (ECML) with some noise from nearby industrial sites including Torness Nuclear Power Station, Dunbar Cement Works and the landfill site and opencast mine to the northwest of Skateraw.
284. A desk-based review and consultation will be undertaken to identify potentially sensitive receptors. Background noise monitoring will be undertaken at residential properties where the potential for significant noise effects from offshore activities is identified, and where needed to inform the construction assessment. Any surveys will be agreed in consultation with East Lothian Council (ELC) throughout the EIA process and will be carried out for a sufficient period to allow typical sound levels to be established, taking account of different types of noise sources and weather conditions that occur. Noise surveys may be accompanied by the acquisition of supplementary non-acoustic data (rainfall and wind records), as required.

Figure 5.4: Airborne Noise Study Area

5.3.4.    Potential Proposed Development Impacts

285. A range of potential impacts on airborne noise have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures:

• Construction

–           Piling activities will generate construction noise that may impact recreational and leisure receptors in the nearshore environment;

–           Change in noise levels causing disturbance to human receptors landward of MLWS;

–           Construction vibration causing disturbance to residents landward of MLWS; and

–           Noise and vibration impacts to ecological/geological receptors landward of MLWS.

• Operation and Maintenance

–           Airborne noise associated with the operation and maintenance of the Proposed Development may impact recreational and leisure receptors in the nearshore environment impact recreational and leisure receptors in the nearshore environment;

–           Airborne noise may exceed guideline levels for commercial fishing vessels and commercial shipping traffic;

–           Airborne noise may exceed guideline values for offshore accommodation platforms; and

–           Impacts on Receptors Landward of MLWS.

• Decommissioning

–           Piling activities will generate decommissioning noise that may impact recreational and leisure receptors in the nearshore environment;

–           Airborne noise may exceed guideline levels for commercial fishing vessels and commercial shipping traffic;

–           Change in noise levels causing disturbance to human receptors landward of MLWS; and

–           Noise and vibration impacts to ecological/geological receptors landward of MLWS.

5.3.5.    Designed in Measures

286. The following designed in measures, and how these can reduce potential for impact have been considered in identification of impacts that have been scoped into the Proposed Development assessment. The designed in measures will evolve over the development process as the EIA progresses and in response to consultation.

Construction and Decommissioning Phases Mitigation

• Core working hours for the construction of the onshore elements of the Proposed Development will be Monday to Sunday 07.00 to 19.00 hour. Activities carried out during mobilisation and maintenance will not generate significant noise levels (such as piling, or other such noisy activities). In certain circumstances, specific works may have to be undertaken outside the normal working hours, such as:

–           HDD or other trenchless construction technology which may require 24-hour machinery operation, dependent on the ground conditions;

–           remedial works, for example in the event of severe weather;

–           delivery of electrical infrastructure;

–           jointing operations along the cable route; and

–           security of sites and protection of open assets.

• Based on noise modelling results, where noise has the potential to cause disturbance the use of mufflers, acoustic barriers and screening will be considered. The construction and decommissioning works would use Best Practicable Means (BPM) to limit the impacts of noise at sensitive receptors. Those measures would be set out in the CEMP. Monitoring of noise related complaints should also be undertaken.

Operation Phase Mitigation

287. Operational measures to be considered as part of the Proposed Development would involve:

• selection of quieter equipment where reasonably practicable;
• installation of acoustic enclosures;
• installation of acoustic barriers;
• silencing of exhausts/outlets for air handling/cooling units; and
• monitoring of noise related complaints and appropriate remedial action.

5.3.6.    Potential Impacts after the Implementation of designed in measures

288. Based on the baseline characterisation and the project description outlined in section 2  Open ▸ , all potential offshore airborne noise impacts seaward of MLWS are proposed to be scoped out of further assessment. These impacts are outlined, together with a justification for scoping them out, in Table 5.5  Open ▸ .

 

Table 5.5: Impacts Proposed to be Scoped Out of the Proposed Development Assessment for Airborne Noise (Landward of MLWS)

5.3.7.    Proposed Approach to the Environmental Impact Assessment

289. Airborne noise is proposed to be scoped out therefore no further detail is presented on proposed assessment methodology.

Potential Cumulative Effects

290. Although there are several other offshore wind farm projects in development in the wider areas of the Proposed Development (including Neart na Gaoithe, Inch Cape and Seagreen Alpha and Bravo), all have been scoped out the assessment of airborne noise from their Environmental Statement (now termed EIA Report) therefore it is proposed that no cumulative assessment is required for the Proposed Development.

Potential Transboundary Impacts

291. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open . No potential transboundary effects have been identified for airborne noise receptors and therefore this will not be considered within the EIAR.

5.3.8.    Scoping Questions to Consultees

• Do you agree that the assessment of airborne noise receptors should be scoped out of the Proposed Development EIA including cumulative and transboundary effects?

5.3.9.    Next Steps

292. The over-arching next steps are outlined in section 4.3.4. In terms of topic specific steps for airborne noise, the next step is to seek agreement on scoping out the assessment of airborne noise from the EIA Report as per agreement on the scoping out through the initial Berwick Bank Wind Farm Scoping Opinion.

 

 

5.4.        Offshore Air Quality

5.4.1.    Introduction

293. This section of the Offshore EIA Scoping Report considers the potential impacts from the construction, operation and maintenance, and decommissioning of the offshore and intertidal components (seaward of the MHWS mark) of the Proposed Development on offshore air quality.
294. Offshore air quality was included in the initial Offshore EIA Scoping Report. Although the change in project scope applied to this Offshore EIA Scoping Report, which is combining the offshore Proposed Development Array Areas, the impacts are anticipated to generally be the same as identified in the initial Scoping Report. The initial Berwick Bank Proposal Scoping Opinion response has been considered for the development of this section. SSER intends to scope out offshore air quality as per agreement on the initial Berwick Bank Wind Farm Scoping Opinion.

5.4.2.    Study Area

295. The onshore air quality study area includes the following in accordance with the Institute of Air Quality Management (IAQM) guidance:

• Designated ecological receptors within 50 m of potential landfall construction activities (Barns Ness SSSI); and
• Human Receptors (Residential Properties and public amenity areas) within 350 m of potential landfall construction activities.

5.4.3.    Baseline Environment

Desktop Study

296. An initial desk-based review of literature and data sources to support this Offshore EIA Scoping Report has identified a number of baseline datasets. These are summarised at Table 5.6  Open ▸ below.

 

Table 5.6: Summary of Key Desktop Reports to inform Offshore Air Quality Scoping Assessment

 

297. Due to industrialisation of the coast and inshore area adjacent to the central North Sea there has been an increase in the levels of pollutants which decrease further offshore, though oil and gas platforms provide numerous point sources of atmospheric pollution (DECC, 2016).
298. The UK agreed to set emission ceilings through the National Emission Ceilings Directive (NECD), which was revised in 2016 (NECD 2016/2284/EU) to set emission reduction commitments for total emissions of NOx, SOx, non-methane volatile organic compounds (NMVOC), Ammonia (NH3) and particulate matter (PM2.5) in 2020 and 2030. The UK has met these reduction targets for all of these pollutants for each year since 2010 inclusive with the exception for NOx for the year 2010 (NECD, 2020).
299. The Scottish Government suggest there have been long-term reductions in emissions for all pollutants due to various policies and strategies implemented within Scotland such as the CAFS – The Road to a Healthier Future (Scottish Government, 2015a and Scottish Government, 2020a), Climate Change (Emissions Reduction Targets) (Scotland) Act (2019) setting a 2045 target for net zero emissions and establishment of Low Emission Zones (The Transport (Scotland) Act 2019).
300. In 2017, the National Atmospheric Emissions Inventory undertook a review of the emissions in Scotland for the eight priority air pollutants: ammonia (NH3), carbon monoxide (CO), NOx, NMVOCs, PM10, PM2.5, SO2, lead (Pb) and dioxins (PCDD/F) and benzo(a)pyrene B[a]p. PM10 describes inhalable particles, with diameters that are generally 10 micrometers and smaller. Between 1990 and 2016, there were decreases of 12% for ammonia, 64% per cent for PM10, 65% for NMVOCs, 72% for nitrogen oxides (NOx), 84% for carbon monoxide, 94% for SO2 and 98% for lead (National Atmospheric Emissions Inventory, 2019).
301. The annual mean concentrations in the vicinity of the potential landfall areas for 2020 are shown in Table 5.7  Open ▸ . The baseline concentration of total oxides of nitrogen (NOx) is relevant for sensitive ecological receptors. The baseline annual mean NOx concentration at the Barns Ness SSSI is 5.1 micrograms per cubic meter of air (µg/m3). The maximum baseline annual mean concentrations within the onshore air quality study area for NO2, PM10 and for PM2.5 are 4.4 µg/m3, 10.6 µg/m3 and 5.6 µg/m3 respectively. All background concentrations within the onshore air quality study area are significantly below the annual mean Air Quality Standards (AQSs) of 30 µg/m3 for NOx, 40 µg/m3 for NO2, 18 µg/m3 for PM10 and 10 µg/m3, for PM2.5 which are applicable in Scotland.

 

Table 5.7: Baseline NO2, PM10 and PM2.5 Concentrations in the Onshore Air Quality Study Area 2020

 

5.4.4.    Potential Proposed Development Impacts

302.         A range of potential impacts on offshore air quality have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures:

• Construction, Operation and Maintenance, and Decommissioning

–           atmospheric emissions from vessel and helicopter movements;

–           generation of dust and particulates at landfall (e.g. from earth moving, directional drilling, open cut trenches)) have the potential to have an adverse (smothering) impact on ecological receptors;

–           generation of dust and particulates at the selected landfall site have the potential to affect human health and cause nuisance as a result of dust soiling of surfaces at residential properties; and

–           exhaust emissions from offshore vessels used in the construction phase having the potential to increase local ambient concentrations of Sulphur Dioxide (SO2), NO2, PM10 and PM2.5 and impact human health.

5.4.5.    Designed in Measures

303. The following designed in measures, and how these can reduce potential for impact have been considered in identification of impacts that are proposed to be scoped into and out of the Proposed Development Offshore EIAR (section 5.4.6, Table 5.8  Open ▸ ).

• A bespoke CoCP will be prepared for the construction phase of the Proposed Development. This will be customised depending on the choice of landfall and will include:

–           a detailed project description with figures illustrating location of proposed construction and operational activities, and main ports used for vessels to and from the offshore construction site;

–           adherence to all legislative requirements;

–           a proposed programme of work;

–           a summary of Environmental Management Procedures including roles and responsibilities, sub-contractors and evidence of training, awareness and competence of on-site personnel;

–           procedures for communication; and

–           details of environmental management plans, including an air quality management plan to minimise the generation and potential impacts of dust emissions on receptors relevant for human health, amenity and ecology.

• Dust and air quality management plan within the CoCP will include good practice measures in accordance with the Institute of Air Quality Management (IAQM) guidance (Scottish Government and Defra, 2017; IAQM, 2018), proportionate to the potential impacts which notes that, even close to well-managed mineral extraction sites in the UK, impacts from release of dust on habitats, are rare. If effects are rare close to large-scale, long-term mineral extraction sites then impacts from smaller-scale, well-managed temporary construction, operation and decommissioning activity can be concluded to be negligible and therefore scoped out of further assessment.

5.4.6.    Potential Impacts after the Implementation of designed in measures

304. Atmospheric emissions from Proposed Development may arise from the combustion of fuel used to power both vessels and helicopters used in the construction, operation and maintenance, and decommissioning of the offshore wind farm. The pollutants from vessels and helicopters include sulphur dioxide (SO2) and carbon dioxide (CO2), oxides of nitrogen (NOX) which represents the sum of nitrogen dioxide (NO2) and nitrogen oxide (NO), and particulate matter (PM10 and PM2.5).
305. Based on the baseline characterisation and the project description outlined in section 2  Open ▸ , all potential offshore air quality impacts are proposed to be scoped out of further assessment. These impacts are outlined, together with a justification for scoping them out, in Table 5.8  Open ▸ .
306. It should be noted that a separate ‘Climatic Effects’ section will be included within the Proposed Development Offshore EIAR.

 

.

Table 5.8: Impacts Proposed to be Scoped Out of the Proposed Development Assessment for Offshore Air Quality

 

 

5.4.7.    Proposed Approach to the Environmental Impact Assessment

307. Offshore air quality is proposed to be scoped out therefore no further detail is presented on proposed assessment methodology.

Potential Cumulative Effects

308. Although there are several other offshore wind farm projects in development (including Neart na Gaoithe, Inch Cape and Seagreen Alpha and Bravo) in the wider areas of the Proposed Development, all have been scoped out of further assessment of air quality from their Environmental Statements due to lack of receptor-impact pathway. SSER therefore proposes that there is no cumulative effect in relation to Air Quality and this pathway is scoped out of further assessment of cumulative effects.

Potential Transboundary Impacts

309. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open . No potential transboundary effects have been identified for offshore air quality and therefore this will not be considered within the EIAR.

5.4.8.    Scoping Questions to Consultees

• Do you agree that the assessment of air quality receptors should be scoped out of the Proposed Development EIA including cumulative and transboundary effects?

5.4.9.    Next Steps

310. The over-arching next steps are outlined in section 4.3.4. In terms of topic specific steps for air quality, the next step is to seek agreement on scoping out the assessment of offshore air quality from the EIA Report. In addition, a Climate Effect Assessment is included (section 5.5.1) and will be assessed presented within the offshore EIA report.

 

5.5.        Climatic Effects Assessment

5.5.1.    Introduction

311. This section of the Offshore EIA Scoping Report outlined the assessment of potential impacts from the construction, operation and maintenance, and decommissioning of the Proposed Development as a whole (onshore and offshore infrastructure) on climate, including consideration of GHG. The GHG assessment would be undertaken as part of a Life Cycle Assessment (LCA) approach; this is considered as a component of the overarching Climate Impact Assessment. The assessment will also consider the resilience of the Proposed Development to climate change and reports on the impacts of climate on the Proposed Development.
312. The Climate Impact Assessment will be provided in the form of a standalone report, appended to the onshore and offshore EIA Reports.
313. The proposed development will be based off the coast of East Lothian in an area that is 40km offshore, with a total area of 1,142 square kilometres. It would be a large array of wind turbines to produce low-carbon energy, to support the Scottish Government in fulfilling its commitment to meeting its carbon reduction goals under the Climate Change (Scotland) Act of 2008, as amended in 2019 (Climate Change (Emission Reductions Targets) (Scotland) Act 2019). This is supporting the UK-wide Climate Change Act of 2008, also as amended in 2019.
314. The UK has so far outperformed on its carbon budget targets as set out in the above legislation, but progress is slowing, and the UK is not on track to meet its future budgets or the overall reduction target, according to the most recent Progress Report to Parliament by the Committee on Climate Change. Renewable energy Proposed Developments, such as Berwick Bank, are an important part in aiding the whole of the UK to meet its future budgets. The proposed development is intended to have the production capacity of 4.1GW at optimal running.

5.5.2.    Study Area

315. The study area for the assessment will be Scotland. The primary recipients will be Marine Scotland, acting on behalf of Scottish Minsiters, and East Lothian Council, who are the council in closest proximity to the site and where Berwick Bank onshore and landfall infrastructure will be located.
316. The Climate Impact Assessment requires overview across assets onshore and offshore, which are each required to produce electricity and route it efficiently to the grid. Figure 1.3  Open ▸ sets out visually how the assets will be arranged onshore and offshore.

Legislative Overview

317. The Town and Country Planning (Environmental Impact Assessment) Regulations 2017 (SI 2015/517) states that a climate change risk assessment should consider both:

• Impact of the scheme on climate: the potential effects of the scheme on climate, in particular, the magnitude of GHG emissions emitted during both construction and operation;
• Impact of climate on the scheme: the vulnerability of the scheme to climate change, in particular, the impacts of extreme weather (caused by climate change) during operation and construction and adaptation to mitigate the effects of these impacts; and
• The assessment will include the above. The Marine (Scotland) Act of 2010 is also relevant, as this legislation sets the context for marine licensing around Scotland.
  318. The policy context will be further elaborated in the assessment.

5.5.3.    Baseline Environment

319. The assessment will elaborate briefly on the current context for Scotland and the UK in terms of their current GHG emissions, as well as their respective carbon reduction targets (the ‘carbon budgets’ set out in relevant legislation).
320. To further characterise the baseline and assessment criteria, SSER and our consultants would welcome the opportunity to implement stakeholder engagement to help inform the assessment being carried out.

5.5.4.    Assessment Methodology

Impact of the Proposed Development on Climate

321. A GHG assessment that takes into account the IEMA Environmental Impact Assessment Guide ‘Assessing Greenhouse Gas Emissions and Evaluating Their Significance’ (IEMA, 2017), will be undertaken, which will capture whole-lifecycle analysis of GHG emissions.
322. To assess the Proposed Development’s effects on climate, the magnitude of GHG emissions from construction and operation are calculated and considered in the context of local and national policy, and Scottish and UK carbon budgets.
323. Emissions will be presented in the context of the reduction in GHG emissions to be replaced by the energy produced by the Proposed Development. The overall lifecycle emissions or emissions reductions will be expressed as a percentage of the carbon budgets for the Scottish and UK Governments with respect to the relevant carbon budgetary periods (currently CB3). A measure of significance will be assigned based on the extent to which the Proposed Development would impact on Scotland’s and the UK’s ability to meet its carbon budgets.
324. The assessment will calculate the GHG emissions associated with the construction, operation and decommissioning of the Proposed Development, with reference to the framework set out in PAS 2080:2016 (Carbon Management in Infrastructure).
325. Emissions will be calculated using Atkin’s Carbon Knowledgebase tool, which contains a detailed library of calculation formulae and over 1,000 emissions factors from authoritative sources such as the Inventory of Carbon and Energy (ICE, versions 1.6(a), 2.0 and 3.0), the Defra Greenhouse Gas Reporting Conversion Factors, and the EMEP/ CORINAIR Emission Inventory Guidebook.
326. Emissions will be presented in the context of the reduction in GHG emissions which will be enabled by the production of zero carbon electricity, from the Proposed Development, as a replacement  of electricity from fossil fuels.
327. A level of significance will be assigned based on the extent to which the Proposed Development would impact the UK’s ability to meet their carbon budgets. To do so we will be assessing the positive and negative adverse effects to determine a carbon balance. To express this, the overall lifecycle emissions or emission reductions will be expressed as a percentage of the UK’s carbon budgets[3].

Impacts of Climate on the Proposed Development

328. The assessment will examine the resilience of the Proposed Development to climate change and report on the impacts of climate on the Proposed Development. The assessment will provide the following:

• An examination of the current climate in the study area using the Met Office’s latest regional dataset of 30-year averages and data from nearby long running meteorological stations;
• A review of observed climate vulnerability effects in the study area;
• Consideration of the Proposed Development future climate in the study area. This uses climate Projections from UKCP18 (United Kingdom Climate Projections 2018). These Projections have been developed by the Met Office Hadley Centre Climate Programme which is supported by the Department of Business, Energy and Industrial Strategy (BEIS) and the Department for Environment, Food and Rural Affairs (Defra). They provide the most up-to-date assessment of how the climate of the UK may change over the 21st century, and that information can be utilised to consider what may happen in this study area;
• Evaluation of how the Proposed Development may be vulnerable to the impacts of climate change during its construction, operation and decommissioning;
• The climate vulnerability assessment would consist of the following:

–           Scoping phase

–           Climate sensitivity assessment

–           Climate exposure assessment

–           Assessment phase

• Identification of specific mitigation to adapt the design, operation and maintenance processes to reduce the Proposed Development’s vulnerability to climate change factors; and
• An assessment of the residual climate change vulnerability of the Proposed Development that, in accordance with appropriate Guidance, e.g. From the DMRB or IEMA, considers the likelihood and consequence of each potential vulnerability.

Data Sources

329. The baseline conditions will be identified through a detailed desktop review. Emissions will be calculated using an approach aligned with the Publicly Available Specification (PAS) 2080:2016 Carbon Management in Infrastructure, the technical standard for calculating and managing GHG emissions associated with infrastructure. Other data and information sources may be identified during the review as part of the EIAR.
330. Details on materials for the assessment of GHG emissions from construction of the Proposed Development will be sought from the design team during the assessment. The climate vulnerability assessment (assessment phase) will adopt UKCP18 climate Projections.

5.5.5.    Likely Significant Effects

Construction and Decommissioning

331. During construction, GHG would be generated by:

• production of construction materials, including primary raw material extraction, manufacturing and intra-manufacturing transportation
• transportation of materials and workforce to the construction site
• combustion of fuel to generate energy for use during construction
• treatment and transport of water for use during construction
• transport, treatment and/or disposal of waste generated during construction
  332. During decommissioning, emissions would be generated by on-site deconstruction processes, the transport of waste materials, and processing for re-use, recycling, recovery or disposal. If material were to be reused or recycled at decommissioning, this would generate an emissions reduction outside the infrastructure boundary as virgin materials would be replaced in future Proposed Developments.

Operation and Maintenance

333. The Proposed Development aim is to produce 4100 MW of electricity (at optimal running) over the 35-year lifetime of the Proposed Development. This will provide the National Grid with an alternative low-carbon energy source and displace the need for energy to be produced via high carbon methods (i.e. fossil fuels). In each 5-year national budgetary period, carbon savings generated could be in the region of 3MtCO2e. It is considered that this would materially aid the UK’s ability to meet its carbon reduction targets.

Summary of Elements to be Assessed

334. Table 5.9  Open ▸ summarises the proposed Scope of the Assessment for Effects on Climate.

 

Table 5.9:  Proposed scope of Assessment for Effects on Climate

 

5.5.6.    Scoping Questions to Consultees

• Do you agree that appropriate methods are proposed based on potential for the development’s impact on the climate?
• Do you agree that appropriate methods are proposed based on potential climatic impacts on the development?