Operation and maintenance phase

Magnitude of impact

Subtidal Habitat IEFs

637. During the operation and maintenance phase of the Proposed Development there is the potential for cumulative impacts with three Tier 3 cable installations. The CEA for the Cambois connection is based on information presented in the Scoping Report submitted in October 2022 (SSER, 2022e). The Cambois connection is a 170 km cable route extending southwards from the Proposed Development array area, it will therefore directly impact the Firth of Forth Banks Complex MPA. Scoping indicates the project will consist of four cables installed in 2 m wide trenches up to 3 m in depth. Installation techniques may include jet trenching or MFE techniques as ground conditions dictate. Site preparation will be required, such as boulder and sand wave clearance as part of the 36 month construction programme. These installation parameters are similar to those of the Proposed Development and therefore the magnitude of the impact on the MPA receptors is anticipated to be low whilst at the coastal receptors this would be negligible.
638. The cumulative impact is predicted to be of local spatial extent, short term duration, intermittent and of high reversibility. The magnitude is therefore, considered to be low.

Intertidal Habitat IEFs

639. Due to the highly limited nature of the operational activities for the Cambois connection, as well as Eastern Link 1 and Eastern Link 2 Cables and their distance from the coast the magnitude of the SSC and associated deposition impact in intertidal habitat IEFs is predicted to be negligible.

Firth of Forth Banks Complex MPA

640. As previously noted, the Cambois connection export cable route extending southwards from the Proposed Development array area and will directly impact the Firth of Forth MPA complex. Eastern Link 1 and Eastern Link 2 are at a greater distance and therefore their operation and maintenance activities are unlikely to impact upon the MPA.
641. As a result, the cumulative impact on the Firth of Forth Banks Complex MPA is predicted to be of local spatial extent, short term duration, intermittent and of high reversibility. The magnitude is therefore, considered to be low.

Berwickshire and North Northumberland Coast SAC

642. As a coastal SAC the magnitude as discussed in paragraph 639 is applicable and therefore the magnitude for the Berwickshire and North Northumberland Coast SAC is expected to be negligible.

Sensitivity of the receptor

Subtidal Habitat IEFs

643. The sensitivity of the IEFs are as detailed in paragraphs 161 to 170, as well as Table 8.21   Open ▸ in the project alone assessment, and in paragraphs 561 to 563 of the CEA assessment.

Intertidal Habitat IEFs

644. The sensitivity of the IEFs are as detailed in paragraphs 171 to 173, as well as Table 8.21   Open ▸ in the project alone assessment, and in paragraphs 565 and 566 of the CEA assessment.

Firth of Forth Banks Complex MPA

645. The sensitivity of the IEFs are as detailed in paragraphs 176 to 180, as well as Table 8.22   Open ▸ in the project alone assessment, and in paragraphs 568 and 569 of the CEA assessment.

Berwickshire and North Northumberland Coast SAC

646. The sensitivity of the IEFs are as detailed in paragraphs 181 to 189, as well as Table 8.23   Open ▸ in the project alone assessment, and in paragraphs 571 to 574 of the CEA assessment.

Significance of the effect

Subtidal Habitat IEFs

647. Overall, for the cobble/stony reef outside of an SAC IEF, the rocky reef outside a SAC IEF and the moderate energy subtidal rock IEF, the magnitude of the impact is deemed to be negligible, and the sensitivity of the receptors is considered to be medium. The effect will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase.
648. Overall, for the subtidal sand and muddy sand sediments IEF and the subtidal coarse and mixed sediments IEF, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor is considered to be low. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase.
649. Overall, for the seapens and burrowing megafauna IEF and the Sabellaria reef outside of an SAC IEF, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor is considered to be negligible. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase. 

Intertidal Habitat IEFs

650. Overall, for the intertidal rock IEF and the fucus dominated intertidal rock IEF, the magnitude of the cumulative impact is deemed to be negligible, and the sensitivity of the receptor is considered to be medium. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase and therefore high likelihood of recovery.
651. Overall, for the intertidal sands IEF, the magnitude of the cumulative impact is deemed to be negligible, and the sensitivity of the receptor is considered to be negligible. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms. 

Firth of Forth Banks Complex MPA

652. Overall, for the subtidal sands and gravels IEF, and the shelf banks and mounds IEF, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor is considered to be low. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase. 
653. Overall, for the ocean quahog IEF, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor is considered to be negligible. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase. 

Berwickshire and North Northumberland Coast SAC

654. Overall, for the mudflats and sandflats not covered by seawater at low tide SAC IEF, the magnitude of the cumulative impact is deemed to be negligible, and the sensitivity of the receptor is considered to be low. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms because of the very small magnitude and intermittent nature of this impact in this phase as well as the large distance between this SAC and the Proposed Development.
655. Overall, for the reefs (subtidal and intertidal rocky reef) IEF, the magnitude of the cumulative impact is deemed to be negligible and the sensitivity of the receptor is considered to be medium. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase as well as the large distance between this SAC and the Proposed Development, which is not significant in EIA terms.
656. Overall, the submerged or partially submerged sea caves IEF, the magnitude of the cumulative impact is deemed to be negligible and the sensitivity of the receptor is considered to be medium. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase as well as the large distance between this SAC and the Proposed Development.
657. Overall, for the large shallow inlets and bays IEF, the magnitude of the cumulative impact is deemed to be negligible and the sensitivity of the receptor is considered to be low. The cumulative impact will, therefore, be of negligible adverse significance, which is not significant in EIA terms, because of the very small magnitude and intermittent nature of this impact in this phase as well as the large distance between this SAC and the Proposed Development. 

Further mitigation and residual effect

658. No benthic subtidal and intertidal ecology mitigation is considered necessary for the impact of increases in SSC and associated sediment deposition during the operation and maintenance phase because the likely effects in the absence of further mitigation (beyond the designed in measures outlined in section 8.10), are not significant in EIA terms.

Decommissioning phase

659. As per the maximum design scenario, during the decommissioning phase all structures above the seabed would be removed. It is proposed to remove all export, inter-array and inter-connector cables and scour protection where possible and appropriate to do so. During decommissioning cables would be removed by similar processes as undertaken during installation therefore increases in suspended sediment concentrations would be of a similar form and magnitude. Following decommissioning, changes in suspended sediments concentration and sedimentation would return to baseline levels as it is anticipated that all structures above the seabed level will be completely removed and no further operation to disturb the seabed would be required. Therefore, the assessment for construction phase is deemed equally applicable for the decommissioning phase and is not repeated here (paragraphs 614 to 636).

Long term subtidal habitat loss

Tier 2

Construction and operation and maintenance phase

Magnitude of impact

Subtidal Habitat IEFs

660. Long term habitat loss will occur directly under all structures on the seabed, associated scour protection and cable protection, where this is required. Magnitude has been considered for the construction and operation and maintenance phases combined as the structures will be placed during construction and will be in place, with habitat loss continuing during the operation and maintenance phase.
661. The installation of the Tier 2 projects outlined in Table 8.34   Open ▸ may lead to cumulative long term subtidal habitat loss of up to 15,014,156 m2 or 0.18% of the benthic subtidal and intertidal ecology CEA study area. Table 8.34   Open ▸ shows all projects/plans/activities considered in the Tier 2 assessment which are Inch Cape Offshore Wind Farm, Neart na Gaoithe Offshore Wind Farm, Seagreen 1, the Seagreen 1A Project, Seagreen 1A Export Cable Corridor, Eastern Link 1 and Eastern Link 2.
662. The presence of offshore infrastructure at the Inch Cape Offshore Wind Farm may result in 2,470,000 m2 of long-term subtidal habitat loss (Inch Cape Offshore Limited, 2018). The presence of offshore infrastructure at Neart na Gaoithe Offshore Wind Farm may result in a total of 361,000 m2 of long-term habitat loss (Mainstream Renewable Power, 2019). The maximum design scenario for long term habitat loss associated with Seagreen 1 and the Seagreen 1A Project have been calculated using the approach, and the publicly available information, detailed in paragraph 490. Using this approach, the presence of offshore infrastructure at Seagreen 1 may result in a total of 2,026,045 m2 of long-term habitat loss (Seagreen Wind Energy, 2012) and the Seagreen 1A Project may result in a total of 158,055 m2 of long-term habitat loss. The Seagreen 1A Export Cable Corridor Environmental Statement does not present a specific value for long term habitat loss, however, it is assumed that cable protection will be 6 m wide and may be required for up to 20% of the 110 km offshore export cable (Seagreen Wind Energy Ltd., 2021). Eastern Link 1’s environmental appraisal does not provide specific values for long term habitat loss except to state rock berm of a 7 m width will be installed. The cables installed as a result of Eastern Link 2 (National Grid Electricity Transmission and Scottish Hydro Electric Transmission plc, 2022) will result in 2,200,200 m2 of long term habitat loss. Additionally only 24% of the 176 km Eastern Link 1 cable and only 18% of the 436 km Eastern Link 2 cables will be within the Proposed Development benthic subtidal and intertidal study area therefore only a proportion of the overall impact will be cumulative. The details of the activities resulting in long term subtidal habitat loss from each wind farm are outlined in Table 8.38   Open ▸ .
663. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and high reversibility. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Table 8.38: Total Area and Component Parts of Long Term Subtidal Habitat Loss of the Relevant Cumulative Projects in Tier 2 the Construction and Operation and Maintenance Phases of the Proposed Development

Firth of Forth Banks Complex MPA

664. Neither Inch Cape Offshore Wind Farm, nor Neart na Gaoithe Offshore Wind Farm have a spatial overlap with the FFBC MPA, however Seagreen 1 and Seagreen 1A Project do overlap with the FFBC MPA. Together Seagreen 1 and Seagreen 1A Project overlaps with 7.17% of the FFBC MPA, which represents 31.59% of the total area of Seagreen 1 and Seagreen 1A Project. Based on the MPA assessment undertaken for Seagreen 1 (including the Seagreen 1A Project elements), up to 1,032,566 m2 of long term subtidal habitat loss from Seagreen 1 and Seagreen 1A Project infrastructure may occur within FFBC MPA, which will occur within Scalp and Wee Bankie and Montrose Bank (MS-LOT, 2014). Seagreen 1A Export Cable Corridor also overlaps with the FFBC MPA, the area of overlap represents 3.8% of the total area of the MPA. The MPA Assessment undertaken for Seagreen 1A Export Cable Corridor assumes that cable protection will be 6 m wide and may cover up to 20% of the 110 km offshore export cables. Not all cable protection, however, will be installed in the MPA and there is the possibility that no cable protection would be required in the MPA for the Seagreen 1A Export Cable Corridor (see Figure 3-4 in Seagreen Wind Energy Ltd., 2021). There may be up to 2,996,164 m2 of cumulative long term habitat loss, from Seagreen 1 and Seagreen 1A Project and the Proposed Development, within the FFBC MPA, which equates to 0.14% of the total area of the MPA.
665. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and high reversibility. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Sensitivity of receptor

Subtidal Habitat IEFs

666. The sensitivity of the IEFs are as detailed in paragraphs 289 to 292 and Table 8.25   Open ▸ .
667. The benthic ecology subtidal IEFs are deemed to be of high vulnerability, low recoverability, and regional to national value. The sensitivity of the IEFs is therefore, considered to be high.
668. Although there is an impact on PMF(s) this will not create significant impact on the national status of these features. This is because of the highly localised nature of the impact only causing habitat loss in discrete locations spread cross the Proposed Development.

Firth of Forth Banks Complex MPA

669. The sensitivity of the IEFs found in FFBC MPA are as detailed in paragraphs 293 to 298 and Table 8.26   Open ▸ .
670. The subtidal sands and gravels IEF and shelf banks and mounds IEF are deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of the IEFs is therefore, considered to be high.
671. The ocean quahog IEF is deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of the IEF is therefore, considered to be high.

Significance of effect

Subtidal Habitat IEFs

672. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor (subtidal sand and muddy sand sediments, subtidal coarse and mixed sediments, Sabellaria reef outside of an SAC, moderate energy subtidal rock IEF, cobble/stony reef outside of an SAC IEF and rocky reef outside an SAC IEF) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of the limited extent of this impact as well as the ability of some of these IEFs to colonise the installed infrastructure.

Firth of Forth Banks Complex MPA

673. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor (subtidal sands and gravels, shelf banks and mounds, and ocean quahog) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of the limited extent of this impact within the wider context of the MPA.

Further mitigation and residual effect

674. No benthic subtidal and intertidal ecology mitigation is considered necessary for the impact long term habitat loss during the decommissioning phase because the likely effects in the absence of further mitigation (beyond the designed in measures outlined in section 8.10), are not significant in EIA terms.

Decommissioning Phase

675. There are no Tier 2 projects active in the Proposed Development decommissioning phase to consider for cumulative impacts based on current knowledge. Any programme changes resulting in decommissioning overlap with the Proposed Development are considered in paragraph 482.

Tier 3

Construction and operation and maintenance phase

Magnitude of impact

Subtidal Habitat IEFs

676. The only Tier 3 projects which have been identified in the CEA with the potential to result in cumulative long-term habitat loss with the Proposed Development is the Cambois connection.
677. The values for the Cambois connection and the predicted extent of long term habitat loss associated with this project is presented in Table 8.39   Open ▸ and are based on information presented in the Cambois connection Scoping Report (SSER, 2022e) submitted in October 2022.
678. The installation of the Tier 2 and 3 projects may lead to cumulative long term subtidal habitat loss of up to 15,320,156 m2 or 0.18% of the benthic subtidal and intertidal ecology CEA study area.
679. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and high reversibility. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Table 8.39: Total Area and Component Parts of Long Term Subtidal Habitat Loss of the Relevant Cumulative Projects in Tier 3 the Construction and Operation and Maintenance Phases of the Proposed Development

Firth of Forth Banks Complex MPA

680. In addition to the cumulative long term habitat loss which will occur as a result of Tier 2 projects, namely Seagreen 1 and Seagreen 1A Project, within the FFBC MPA Cambois connection also overlaps with the FFBC MPA. For the Cambois connection it is assumed that cable protection will be 3 m wide and may cover up to 15% of the four 170 km offshore export cables, however only up to 252 km of the total 680 km of cables could occur within the FFBC MPA, resulting in a maximum potential habitat loss of up to 113,400 m2 associated with cable protection within the FFBC MPA. This represents 0.0053% of the total area of the MPA or 0.02% of the total area of Berwick Bank. Not all cable protection, however, will be installed in the MPA and there is the possibility that no cable protection would be required in the MPA as the locations are not yet known. This results in up to 3,109,565 m2 of cumulative long term habitat loss, from Seagreen 1, Seagreen 1A Project, Cambois connection and the Proposed Development, within the FFBC MPA, which equates to 0.15% of the total area of the MPA.
681. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and low reversibility during the lifetime of the Proposed Development. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Sensitivity of receptor

Subtidal Habitat IEFs

682. The sensitivity of the receptors is detailed in paragraphs 666 to 668.

Firth of Forth Banks Complex MPA

683. The sensitivity of the receptors is detailed in paragraphs 669 to 671.

Significance of effect

Subtidal Habitat IEFs

684. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptors (subtidal sand and muddy sand sediments, subtidal coarse and mixed sediments, Sabellaria reef outside of an SAC, moderate energy subtidal rock IEF, cobble/stony reef outside of an SAC IEF and rocky reef outside an SAC IEF) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of the limited extent of this impact across these IEFs as well as the ability of some of these IEFs to utilise the new infrastructure.

Firth of Forth Banks Complex MPA

685. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptors (subtidal sands and gravels, shelf banks and mounds, and ocean quahog) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, this is because of the limited extent of the infrastructure within these IEF and the lack of deteriorative effects.

Further mitigation and residual effect

686. No benthic subtidal and intertidal ecology mitigation is considered necessary for the impact long term habitat loss during the decommissioning phase because the likely effects in the absence of further mitigation (beyond the designed in measures outlined in section 8.10), are not significant in EIA terms.

Decommissioning phase

687. There are not any Tier 3 projects active in the Proposed Development decommissioning phase to consider for cumulative impacts based on current knowledge. Any programme changes resulting in decommissioning overlap with the Proposed Development are considered in paragraph 482.

Colonisation of hard structures

Tier 2

Operation and maintenance phase

Subtidal Habitat IEFs

688. The introduction of hard substrate into areas of predominantly soft sediments has the potential to alter community composition and biodiversity. This impact is only relevant to the operation and maintenance phase as colonisation can only begin post construction. The presence of the projects listed in Table 8.34   Open ▸ has the potential to lead to cumulative impacts arising from the colonisation of up to 17,513,271 m2 of hard structures (0.21% of the benthic subtidal and intertidal ecology CEA study area) from 617 wind turbines, 19 OSPs/Offshore convertor station platforms, five meteorological masts, 1,049.45 km of cable protection and 88 cable crossings. Table 8.34   Open ▸ lists all projects/plans/activities considered in the Tier 2 assessment which are Inch Cape Offshore Wind Farm, Neart na Gaoithe Offshore Wind Farm, Seagreen 1, the Seagreen 1A Project, the Seagreen 1A Export Cable Corridor, Eastern Link 1 and Eastern Link 2.
689. There are no values provided in the Environmental Statement for Seagreen 1A Export Cable Corridor however 20% of the 110 km may require cable protection up to 6 m wide (Seagreen Wind Energy Ltd., 2021).
690. Inch Cape Offshore Wind Farm is likely to contribute to cumulative impacts from the colonisation of hard structures through the presence of 213 wind turbines, five substations, and three meteorological mast, as well as cable protection for the inter-array and offshore export cables. In the Environmental Statement, it is stated that the amount of new hard substrate resulting from Inch Cape Offshore Wind Farm is equivalent to the amount of long term habitat loss (Inch Cape Offshore Limited, 2018) which is described in Table 8.38   Open ▸ and equates to 2,470,000 m2 of new hard structures (Inch Cape Offshore Limited, 2018).
691. At the Neart na Gaoithe Offshore Wind Farm colonisation of hard substrate is likely to result from the presence of gravity base foundations for the wind turbine foundations, substation foundations, scour protection and cable protection. The amount of new hard substrate available equates to 460,000 m2 of new hard structures (Mainstream Renewable Power, 2019).
692. The Seagreen 1 maximum design scenarios for colonisation of hard structures, as stated in the Environmental Statement (Seagreen Wind Energy, 2012), assumes that the area available for colonisation is expected to be approximately the same area as is considered for long term habitat loss, the components of which are described in Table 8.38   Open ▸ . The methodology adopted for the purposes of this assessment to calculate the maximum design scenario for the 114 wind turbines associated with Seagreen 1 is outlined in paragraph 490. The maximum design scenario for Seagreen 1 equates to up to 2,026,045 m2 of new hard structure (Seagreen Wind Energy, 2012).
693. The maximum design scenario for the Seagreen 1A Project has been calculated using the methodology and publicly available information outlined in paragraph 490. Using these assumption, the area available for colonisation as a result of the Seagreen 1A Project is expected to be approximately the same area as that considered for long term habitat loss, the components of which are described in Table 8.38   Open ▸ and equates to 158,055 m2 of new hard structure.
694. The hard substrate installed for Eastern Link 1 includes rock berm with a maximum width of 7 m, no further values regarding hard substrate have been provided (National Grid Electricity Transmission and Scottish Power Transmission, 2022).
695. The hard substrate installed for Eastern Link 2 includes rock berms up to 138 km, six pipeline crossings, 18 cable crossings and rock protection at the landfall. The amount of new hard substrate available is equivalent to the amount of long term habitat loss which is described in Table 8.38   Open ▸ and equates to 2,200,200 m2 of new hard structures (National Grid Electricity Transmission and Scottish Hydro Electric Transmission plc, 2022).
696. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and high reversibility. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Firth of Forth Banks Complex MPA

697. Neither Inch Cape Offshore Wind Farm, nor Neart na Gaoithe Offshore Wind Farm have a spatial overlap with the FFBC MPA, however Seagreen 1 and Seagreen 1A Project do overlap with the FFBC MPA. In total Seagreen 1 and Seagreen 1A Project overlaps with 7.17% of the FFBC MPA, which represents 31.59% of the total area of Seagreen 1 and Seagreen 1A project. Based on the MPA assessment for Seagreen 1 and Seagreen 1A Project MS-LOT, 2014), 1,032,566 m2 of long term subtidal habitat loss from Seagreen 1 and Seagreen 1A Project infrastructure may occur within FFBC MPA, all of which within Scalp and Wee Bankie (Marine Scotland, 2014). Whilst not all of this will represent habitat creation, for the purposes of this assessment it is conservatively assumed to be equivalent. The Seagreen 1A Export Cable Corridor also overlaps with the FFBC MPA, the area of overlap represents 3.8% of the total area of the MPA. The MPA Assessment undertaken for Seagreen 1A Export Cable Corridor assumes that cable protection will be 6 m wide and may cover up to 20% of the 110 km offshore export cables. Not all cable protection, however, will be installed in the MPA and there is the possibility that no cable protection would be required in the MPA for the Seagreen 1A Export Cable Corridor (see Figure 3-4 in Seagreen Wind Energy Ltd., 2021). There may be up to 3,748,131 m2 of cumulative long term habitat creation within the FFBC MPA resulting from Seagreen 1 and Seagreen 1A Project together with the Proposed Development, which equates to 0.18% of the total area of the MPA.
698. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and high reversibility. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Sensitivity of the receptor

Subtidal Habitat IEFs

699. The sensitivity of the IEFs are as detailed in paragraphs 329 to 336.
700. All of the benthic ecology subtidal IEFs are deemed to be of high vulnerability, low recoverability, and regional to national value. The sensitivity of the IEFs is therefore, considered to be high.
701. Although there is an impact on PMF(s) this will not create significant impact on the national status of these features. Colonisation is likely to only occur on new infrastructure and not extend far beyond the infrastructure because the communities colonising the hard structures are unlikely to be suited to the sedimentary habitats which the Proposed Development is largely composed of. In regard to rocky and cobble/stony reefs the species which colonise the hard substrate are likely to be similar to the baseline communities therefore potentially extending the available space for communities from these IEFs. Ultimately the colonisation of new structures is unlikely to present a change in the seabed habitats and therefor the national status of the relevant PMF(s) will be preserved.

Firth of Forth Banks Complex MPA

702. The sensitivity of the IEFs are as detailed in paragraphs 338 to 340.
703. The subtidal sands and gravels IEF and the shelf banks and mounds IEF are deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of the IEFs is therefore, considered to be high.
704. The ocean quahog IEF is deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of the IEF is therefore, considered to be high.

Significance of the effect

Subtidal Habitat IEFs

705. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor (subtidal sand and muddy sand sediments, subtidal coarse and mixed sediments, Sabellaria reef outside of an SAC, moderate energy subtidal rock IEF, cobble/stony reef outside of an SAC IEF and rocky reef outside an SAC IEF) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of the limited extent of this impact across these IEFs as well as the ability of some of these IEFs to utilise the new infrastructure.

Firth of Forth Banks Complex MPA

706. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptor (subtidal sands and gravels, shelf banks and mounds, and ocean quahog) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, this is because of the limited extent of the infrastructure within these IEF and the lack of deteriorative effects.

Further mitigation and residual effect

707. No benthic subtidal and intertidal ecology mitigation is considered necessary for the impact of colonisation of hard structures because the likely effects in the absence of further mitigation (beyond the designed in measures outlined in section 8.10), are not significant in EIA terms.

Tier 3

Operation and maintenance phase

Subtidal Habitat IEFs

708. The Tier 3 projects which have been identified in the CEA with the potential to result in cumulative colonisation of hard substrate with the Proposed Development is the Cambois connection.
709. The Cambois connection has the potential to create 306,000 m2 of new hard habitat associated with rock/mattress cable protection which represents protection covering 15% the total length the four offshore export cables, therefore it is likely that only a proportion of the cable protection will occupy the benthic subtidal and intertidal ecology CEA study area, or potentially none of it. The cable protection represents a change in seabed type, the effects of which are described in paragraphs 319 to 323, however as the cable protection does not extend in to the water column the opportunity for colonisation by some species is reduced. The presence of the Tier 2 and 3 projects has the potential to lead to cumulative impacts arising from the colonisation of up to 17,819,271 m2 of hard structures (0.21% of the benthic subtidal and intertidal ecology CEA study area).
710. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and high reversibility. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Firth of Forth Banks Complex MPA

711. In addition to the cumulative hard structures resulting from Tier 2 projects, namely Seagreen 1 and Seagreen 1A Project, within the FFBC MPA, Cambois connection also overlaps with the FFBC MPA. For Cambois connection it is assumed that cable protection will be 3 m wide and may cover up to 15% of the four 170 km offshore export cables, however only 252 km of cable will be within the FFBC MPA, resulting in a maximum of up to 113,400 m2 of habitat creation associated with cable protection for this project within the FFBC MPA. This represents 0.005% of the total area of the MPA or 0.02% of the total area of Berwick Bank. Not all cable protection, however, will be installed in the MPA and there is the possibility that no cable protection would be required in the MPA as the locations are not yet known. This results in up to 3,861,531 m2 of cumulative area of hard structures which could be colonised, from Seagreen 1, Seagreen 1A Project, Cambois connection and the Proposed Development, within the FFBC MPA, which equates to 0.18% of the total area of the MPA.
712. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and low reversibility during the lifetime of the Proposed Development. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Sensitivity of the receptor

Subtidal Habitat IEFs

713. The sensitivities of the subtidal habitat IEFs are described in paragraphs 699 to 701.

Firth of Forth Banks Complex MPA

714. The sensitivities of the Firth of Forth banks Complex MPA IEFs is described in paragraphs 702 to 704.

Significance of the effect

Subtidal Habitat IEFs

715. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptors (subtidal sand and muddy sand sediments, subtidal coarse and mixed sediments, Sabellaria reef outside of an SAC, moderate energy subtidal rock IEF, cobble/stony reef outside of an SAC IEF and rocky reef outside an SAC IEF) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of the limited extent of this impact across these IEFs as well as the ability of some of these IEFs to utilise the new infrastructure.

Firth of Forth Banks Complex MPA

716. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the receptors (subtidal sands and gravels, shelf banks and mounds, and ocean quahog) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms this is because of the limited extent of the infrastructure within these IEF and the lack of deteriorative effects.

Further mitigation and residual effect

717. No benthic subtidal and intertidal ecology mitigation is considered necessary for the impact of colonisation of hard structures because the likely effects in the absence of further mitigation (beyond the designed in measures outlined in section 8.10), are not significant in EIA terms.

Increased risk of introduction and spread of invasive and non-native species

Tier 2

Construction, operation and maintenance and decommissioning phases

718. The risk of introduction and spread of INNS during the construction, operation and maintenance, and decommissioning phases of the cumulative projects has been considered in this assessment. Magnitude has been considered for all three phases combined as the increased risk of introduction and spread of INNS is as a result of all phases combined.

Magnitude of impact

Subtidal Habitat IEFs

719. The introduction of hard substrate into areas of predominantly soft sediments has the potential to alter community composition and biodiversity and to facilitate the spread/introduction of INNS. The latter may be particularly important with regards to cumulative impacts as several offshore structures in relatively close proximity could enable the spread of INNS. Table 8.34   Open ▸ lists all projects/plans/activities considered in the Tier 2 assessment which are Inch Cape Offshore Wind Farm, Neart na Gaoithe Offshore Wind Farm, Seagreen 1, the Seagreen 1A Project, Seagreen 1A Export Cable Corridor, Eastern Link 1 and Eastern Link 2. The total cumulative area of hard structures available for colonisation is expected to be up to 15,313,071 m2. Additionally, there may be up to 210,800 cumulative vessel trips, not including those for Neart na Gaoithe.
720. Inch Cape Offshore Wind Farm has the potential to introduce INNS in the construction phase through the movement of vessels (six per day during the operation and maintenance phase) associated with the installation of the wind turbines, substations, inter-array and offshore export cables, and the associated works (Inch Cape Offshore Limited, 2018). In the operation and maintenance phase of the project INNS introduction can result from the introduction of new substrate installed in the construction phase, the amount of hard substrate introduced is equivalent to the long term habitat loss which is described in Table 8.38   Open ▸ (Inch Cape Offshore Limited, 2018).
721. Neart na Gaoithe Offshore Wind Farm has the potential to introduce INNS in the construction and operation and maintenance phase as a result of the introduction of hard substrate, the area of the projects which is considered to be equal to the area of long term habitat loss (Mainstream Renewable Power, 2019). This involves the introduction of wind turbines, substations, meteorological masts, and inter-array and offshore export cables protection. The details of which are in paragraph 691(Mainstream Renewable Power, 2019). Vessel movements may also contribute to INNS however no quantification of this is provided in the environmental statement.
722. The Seagreen 1 assessment did not consider the risk of INNS; however, INNS introduction and spread could result from the introduction of foundations for the 114 and other offshore infrastructure, the details of which are in Table 8.38   Open ▸ (Seagreen Wind Energy, 2012). Additionally, the risk of the spread and introduction of INNS may occur during operation and maintenance as a result of the potential for a maximum of 52,800 trips by maintenance vessels over the maximum 30-year lifespan of the wind farm.
723. The Seagreen 1A Project did not consider the risk of INNS; however, INNS may result from the introduction of foundations for 36 wind turbines and the other offshore infrastructure detailed in Table 8.38   Open ▸ . Additionally, the risk may be increased during the operation and maintenance of Seagreen 1A Project from maintenance vessels movements within the project area over the maximum 30-year lifespan of the wind farm.
724. There are no values provided for Seagreen 1A Export Cable Corridor however up to 20% of the 110 km cable may require cable protection up to 6 m wide (Seagreen Wind Energy Ltd., 2021).
725. The environmental appraisals for Eastern Link 1 and 2 did not specifically evaluate this impact however there is the potential for the introduction of INNS as a result of hard substrate introduction which is considered to be equal to the area of long term habitat loss. The details of which are in Table 8.38   Open ▸ (National Grid Electricity Transmission and Scottish Power Transmission, 2022; National Grid Electricity Transmission and Scottish Hydro Electric Transmission plc, 2022). Vessel movements may also contribute to INNS however no quantification of this is provided in the environmental appraisal.
726. The introduction and spread of INNS during the decommissioning phase in each project is expected to be the same as the construction phase as similar activities will occur.
727. The total cumulative area of hard structures available for colonisation by INNS is expected to be up to 17,513,271 m2. Additionally, there will be 210,800 cumulative vessel trips, not including those for Neart na Gaoithe.
728. The cumulative impact is predicted to be of regional spatial extent, long term duration, continuous and low reversibility for the lifetime of the Proposed Development. It is predicted that the impact will affect the receptor directly. The magnitude is therefore considered to be low.

Firth of Forth Banks Complex MPA

729. Neither Inch Cape Offshore Wind Farm, nor Neart na Gaoithe Offshore Wind Farm have a spatial overlap with the FFBC MPA, however Seagreen 1 and Seagreen 1A Project do overlap with the FFBC MPA. In total Seagreen 1 and Seagreen 1A Project overlaps with 7.17% of the FFBC MPA, which represents 31.59% of the total area of Seagreen 1 and Seagreen 1A Project. Based on the MPA assessment for Seagreen 1 and Seagreen 1A Project, 1,032,566 m2 of long term subtidal habitat loss associated with Seagreen 1 and Seagreen 1A Project infrastructure may occur within FFBC MPA, all of which will occur within Scalp and Wee Bankie (MS-LOT, 2014). Seagreen 1A Export Cable Corridor also overlaps with the FFBC MPA, the area of overlap represents 3.8% of the total area of the MPA. The MPA Assessment undertaken for Seagreen 1A Export Cable Corridor (Seagreen Wind Energy Ltd., 2021) assumes that cable protection will be 6 m wide and may be required for up to 20% of the 110 km offshore export cables. Not all cable protection, however, will be installed in the MPA and there is the possibility that no cable protection would be required in the MPA for the Seagreen 1A Export Cable Corridor (see Figure 3-4 in Seagreen Wind Energy Ltd., 2021). There may be up to 3,748,131 m2 of cumulative hard structures which would increase the risk of INNS introduction and spread within the FFBC MPA resulting from Seagreen 1 and Seagreen 1A Project together with the Proposed Development, which equates to 0.18% of the total area of the MPA.
730. The cumulative impact is predicted to be of local spatial extent, long term duration, continuous and low reversibility for the lifetime of the Proposed Development. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be low.

Sensitivity of receptor

Subtidal Habitat IEFs

731. The sensitivity of the IEFs are as detailed in paragraphs 372 to 382, as well as Table 8.27   Open ▸ .
732. The subtidal sand and muddy sand sediments IEF, and the subtidal coarse and mixed sediments IEF are deemed to be of high vulnerability, low recoverability, and regional value. The sensitivity of all the IEFs is therefore, considered to be high.
733. The moderate energy subtidal rock IEF is deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of all the IEFs is therefore, considered to be high.
734. The Sabellaria reef outside of an SAC IEF is deemed to be of low vulnerability, high recoverability, and national value. The sensitivity of the IEF is therefore, considered to be low.
735. The seapens and burrowing megafauna IEF, the cobble/stony reef outside of an SAC IEF, and the rocky reef outside an SAC IEF do not have enough evidence in MarESA or FeAST to determine their sensitivity to INNS. A precautionary approach therefore assumes that they are deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of the IEFs is therefore, considered to be high.
736. Although there is an impact on PMF(s) this will not create significant impact on the national status of these features. This can be justified as the potential area if impact based on the designed in measures to reduce the potential introduction of INNS coupled with the very small amount of relevant INNS in the region, as well as the suitability of these habitats to the INNS in the area means the impact is unlikely to change the national status of these PMF(s).

Firth of Forth Banks Complex MPA

737. The sensitivity of the IEFs within the FFBC MPA are as detailed in paragraphs 383 to 386, as well as Table 8.28   Open ▸ .
738. The subtidal sands and gravels IEF and the shelf banks and mounds IEF are deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of the IEFs is therefore, considered to be high.
739. Ocean quahog were not assessed by either MarESA or FeAST so their sensitivity to INNS is unknown. They are however slow to reach sexual maturity, taking between 5 and 11 years depending on growth rate (Thorarinsdóttir, 1999), which could lead to a high sensitivity to INNS which are often characterised by their ability to spread quickly, ocean quahog may struggle to compete as a result. A precautionary approach therefore assumes that they are deemed to be of high vulnerability, low recoverability, and national value. The sensitivity of the IEF is therefore, considered to be high.

Significance of effect

Subtidal Habitat IEFs

740. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of the subtidal habitat receptors (subtidal sand and muddy sand sediments IEF, the subtidal coarse and mixed sediments IEF and moderate energy subtidal rock IEF) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of limited ability of most invasive species to colonise the majority of these IEFs, where invasive species may be introduced measures put in place make the overall risk low and there is already high vessel traffic in this area.
741. Overall, for the Sabellaria reef outside of an SAC IEF, the magnitude is deemed to be low and the sensitivity of the receptor is considered to be low. The effect will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of the ability of this IEF to continue to thrive alongside other encrusting species.

Firth of Forth Banks Complex MPA

742. Overall, the magnitude of the cumulative impact is deemed to be low, and the sensitivity of all receptors (subtidal sands and gravels, shelf banks and mounds, and ocean quahog) is considered to be high. The cumulative impact will, therefore, be of minor adverse significance, which is not significant in EIA terms, because of the limited ability of most invasive species to colonise the majority of these IEFs as soft sediment habitats.

Further mitigation and residual effect

743. No benthic subtidal and intertidal ecology mitigation is considered necessary for the impact of the increased risk of introduction and spread of INNS during the construction phase because the likely effects in the absence of further mitigation (beyond the designed in measures outlined in section 8.10), are not significant in EIA terms.