3.6. Health and Safety
- Risk assessments for all elements of the Array will be undertaken as per the relevant government guidance and the Applicant’s good practice procedures. The risk assessments will form the basis of the methods and safety mitigations put in place across the lifetime of the Array.
3.7. Waste Management
- The construction and decommissioning phases of the Array in particular will generate waste. A Site Waste Management Plan (SWMP) will be prepared and will describe the procedures for handling waste materials, the quantities of waste types generated as a result of the Array activities, and how these will be managed (e.g. disposal, reuse, recycle or recovery). Information on the management arrangements for the identified waste types and management facilities in the vicinity of the Array will also be provided within the SWMP.
- The SWMP will be provided prior to construction when further detailed design information is available.
3.8. Decommissioning Phase
- In line with the requirements under Section 105 of the Energy Act 2004 (as amended), described fully in volume 1, chapter 2, the Applicant will prepare a DP2 for approval by the Scottish Ministers which will include anticipated costs and financial securities, and consider good industry practice, guidance and legislation relating to decommissioning at the time.
- At the end of the Array’s operational lifetime, it is expected that all structures above the seabed (with the exception of driven piles and DEAs (depending upon anchor system used), scour protection and cable protection) will be fully removed where feasible. Driven piles and/or DEAs installed as part of the wind turbine anchoring system, static portions of inter-array cables, interconnector cables, scour protection and cable protection are either expected to remain in situ or method of decommissioning is yet to be determined. Legislation, guidance and good practice will be kept under review throughout the lifetime of the Array and will be followed at the time of decommissioning. Environmental conditions and sensitivities will also be considered since removal of structures may result in greater environmental impacts in comparison to leaving in situ.
- The sequence of decommissioning is likely to be the reverse of the construction sequence, and similar types and numbers of vessels and equipment are expected to be involved. The Lease Agreement, which will be signed with CES, will require the Array to be decommissioned at the end of its lifetime.
3.8.1. Offshore Decommissioning
Floating wind turbine components
- The integrated floating wind turbines (i.e. floating wind turbine and floating foundation) will be removed from site by reversing the methods used to install them.
Wind turbine floating foundations – mooring and anchoring systems
- Mooring lines will be fully removed from site where this be feasible and practicable. It may not be feasible to fully remove anchors where they are embedded in the seabed (e.g. DEAs or driven piles). These are expected to be left in situ and will follow good practice and consideration of environmental conditions and sensitivities This will be reviewed throughout the lifetime of the Array and the most up to date and good practice guidance at time of decommissioning will be followed. The most adverse scenario has been assessed for each topic within this Array EIA Report.
OSP topsides
- OSP topsides will be fully removed from site by reversing the methods used to install them.
OSP fixed jacket foundations
- Driven piles will be cut at seabed level and left in situ, depending on seabed mobility, to reduce further disruption of the seabed. This will be reviewed throughout the lifetime of the Array and the most up to date and good practice guidance at time of decommissioning will be followed. The most adverse scenario has been assessed for each topic within this Array EIA Report. Jackets will be fully removed from site.
Scour protection
- It is currently proposed that scour protection will be left in situ subject to the final material used. Good practice guidance at time of decommissioning will be followed. The most adverse scenario has been assessed for each topic within this Array EIA Report.
Inter-array cables and interconnector cables
- The dynamic portion of the inter-array cables within the water column will be fully removed. The approach for decommissioning the static portion of the inter-array cables and the interconnector cables on the seabed is yet to be determined, however, this will be reviewed throughout the lifetime of the Array and good practice guidance at time of decommissioning will be followed. Where cables remain buried these may be cut and left in situ taking account of environmental sensitivity at the time of decommissioning. The most adverse scenario has been assessed for each topic within this Array EIA Report.
Cable protection
- The approach for decommissioning the cable protection systems is yet to be determined, however, this will be reviewed throughout the lifetime of the Array and good practice guidance at time of decommissioning will be followed. The most adverse scenario has been assessed for each topic within this Array EIA Report.
3.9. Repowering
- Although it is standard procedure for sectors where a non-renewable resource is being exploited, such as oil and gas, for removal of all structures on the seabed as part of offshore decommissioning, the alternative option of repowering may be considered for offshore renewables – especially as, at the time of decommissioning, the need for the power generated will likely still exist.
- The operational life of the Array is expected to be 35 years, during which there will be a requirement for upkeep and maintenance of the Array, as described in section 3.5.
- ‘Repowering’ of the Array at or near the end of its design life may be considered suitable, for example, where new technology becomes available. In this example, wind turbines and/or foundations may be reconstructed and replaced with those of a different specification or design. If the specifications and designs of the new wind turbines and/or foundations fell outside of the MDS or if the impacts associated with the construction, operation and maintenance, and/or decommissioning of the wind turbines and/or foundations were to fall outside those considered by this Array EIA Report, further consent(s) (and potentially an EIA Report) would be required for repowering. Therefore, this is outside of the scope of this Array EIA Report.
3.10. Designed in Measures
- A number of designed in measures have been considered as part of the PDE which the Applicant commits to deliver as part of the development of the Array. Table 3.34 Open ▸ presents the designed in measures for the Array. As these measures have been incorporated into the description of the Array, they have also been considered within the topic specific assessments within volume 2, chapters 7 to 20. Further details of the designed in measures, secondary mitigation and monitoring commitments are provided in volume 3, appendix 6.3.
Table 3.34: Designed In Measures for the Array
3.11. Residues, Emissions and Waste
- A description of the anticipated residues and emissions and wastes arising from the Array and a description of the LSE1 resulting from the emission of pollutants, noise, vibration, light, heat and radiation, the creation of nuisances, and the disposal and recovery of waste are required as per the EIA Regulations. These requirements, and where these are addressed in the Array EIA Report, are presented in Table 3.35 Open ▸ .
Table 3.35: Residues and Emissions
3.12. Natural Resources
- A description of the anticipated LSE1 resulting from the use of natural resources is also required to be provided as per the EIA Regulations. These requirements, and where these are addressed in the Array EIA Report, are presented in Table 3.36 Open ▸ .
3.13. Risk of Major Accidents and Disasters
- Volume 2, chapter 16 assesses the risk of major accidents and disasters which may arise from the Array.