1. Introduction

1. Berwick Bank Wind Farm Limited (BBWFL) is a wholly owned subsidiary of SSE Renewables (SSER) Limited and will hereafter be referred to as ‘the Applicant’. The Applicant is developing the Berwick Bank Wind Farm (hereafter referred to as ‘the Project’). This Marine Archaeology Technical Report presents baseline information for the offshore environment in the Firth of Forth offshore wind farm development Zone. The Marine Archaeology Technical Report covers the offshore elements of the Project located seaward of Mean Low Water Springs (MLWS) (henceforth referred to as the Proposed Development). The onshore transmission elements of the Project are being applied for separately. The onshore archaeology and cultural heritage assessment which includes the intertidal zone is provided in volume 1, chapter 10 of the Berwick Bank Wind Farm Onshore Environmental Impact Assessment (EIA) Report (SSER, 2022a).
2. The baseline described in the Marine Archaeology Technical Report underpins mitigation measures proposed within the Applicant’s Written Scheme of Investigation (WSI), which includes a Protocol of Archaeological Discoveries (PAD). In November 2021, the Marine Archaeology Technical Report and Outline WSI were shared with Scottish Borders Council (SBC), Historic Environment Scotland (HES) and East Lothian Council Archaeology Service (ELC). HES and SCB confirmed that the mitigation was considered adequate[1] to avoid significant impacts (in EIA terms) on marine archaeology and it was appropriate for the Applicant to scope marine archaeology out of the EIA.
3. In June 2022, the Berwick Bank Wind Farm boundary was revised and the Proposed Development array area was reduced by approximately 20 percent. The assessments presented in the final Application are based on new Proposed Development boundaries and an updated Project Design Envelope. No significant changes have been made to the Proposed Development export cable corridor or landfall or the Proposed Development array area which falls entirely within the previous Proposed Development boundary.
4. The Marine Archaeology Technical Report and WSI have been updated to account for the location of anomalies and known archaeological assets relative to a revised marine archaeology study area that corresponds with the new Proposed Development boundaries. The updated WSI is available in the Berwick Bank Wind Farm Offshore EIA Report (at volume 4, appendix 22, annex D). The updated Marine Archaeology Technical Report (this report) is provided as an ‘accompanying document’ to the Application to ensure that the archaeological baseline that corresponds to the WSI is available to consultees.
5. The Applicant’s responses to feedback received during consultation (see Table 1.1   Open ▸ ). The updated Marine Archaeology Technical Report does not report any updates to marine archaeology baseline for the revised marine archaeology study area that might warrant changes to the general methodology and procedures in the WSI and the fundamental conclusions are unchanged.

1.2. Purpose of this Report

6. The aim of this Marine Archaeology Technical Report is to provide an overview of the offshore archaeological baseline associated with the Proposed Development. The objectives of this study are to:

• summarise the potential for submerged prehistoric archaeology to be encountered within the marine archaeology study area ( Figure 1.1   Open ▸ ).
• identify known maritime and aviation sites, and based on the maritime history of the marine archaeology study area and the wider area, assess the potential for the existence of unknown sites and materials within the Proposed Development site;
• present site-specific geophysical data from surveys across the Proposed Development array area and Proposed Development export cable corridor, identify anomalies of archaeological interest and characterise these anomalies integrating the results of the site-specific survey data with the findings of a desk-based review;
• review available site-specific geophysical data for sediments of archaeological and palaeo-environmental interest and integrate the results with the findings of the desktop review; and
• highlight updates to the baseline that might require additional mitigation measures or adaptations to the strategy.
  7. The structure of the report is as follows:
• Section 2: planning policy and legislation: sets out the relevant legislation, policy and guidance in relation to the known and potential marine archaeology within the marine archaeology study area;
• Section 3: methodology: presents the marine archaeology study area ( Figure 1.1   Open ▸ ), the scope of this study and the methodology and evidence used to define the baseline environment;
• Section 4: baseline environment; characterises the known and potential submerged prehistoric and maritime archaeology within the marine archaeology study area:

–           Section 4.1: seabed and topography: describes the seabed and topography within the marine archaeology study area, as informed by site-specific surveys;

–           Section 4.2: submerged prehistoric archaeology: characterises the known and potential submerged prehistoric archaeology within the marine archaeology study area;

–           Section 4.3: maritime archaeology: characterises the baseline environment in relation to maritime archaeology by chronological period;

–           Section 4.4: Designated, Known and Recorded Wrecks: presents the results of a desktop review of designated, known and recorded wrecks within the marine archaeology study area; and

–           Section 4.5: archaeological assessment of seabed contacts identified during geophysical survey: presents the results of the geophysical assessments undertaken to identify anomalies of anthropogenic origin and therefore of archaeological potential.

• Section 5: conclusions: presents the known and potential for submerged prehistoric and maritime archaeology within the marine archaeology study area.

Figure 1.1:  Marine Archaeology Study Area and Marine Archaeology Study Area (Revised July 2022

Table 1.1: Summary of Key Consultation and How This was Considered Within Marine Archaeological Technical Report, Written Scheme of Investigation and or Protocol for Archaeological Discoveries

2. Planning and Legislation

2.1. Legislative Context

8. This section outlines the legislation, policy, guidance and development plans relevant to offshore archaeological remains in the context of offshore renewable energy development.

2.1.2. Marine (Scotland) Act 2010

9. Marine historic assets of national importance within Scottish Territorial Waters (STW) are protected primarily by the Marine (Scotland) Act 2010 (content available on the UK Government Website accessed August 2022 - legislation.gov.uk), in particular Part 5 Section 73. This states that an area may be designated as an Historic Marine Protected Area (MPA) if Scottish Ministers consider it desirable to preserve a marine historic asset which is located in the area.
10. A marine historic asset is defined as a vessel, vehicle or aircraft (or part of), the remains of a vessel, vehicle or aircraft (or part of), an object contained in or formerly contained in a vessel, vehicle or aircraft, a building or other structure (or part of), a cave or excavation, and a deposit or artefact or any other thing which evidences previous human activity.
11. The purpose of Historic MPAs is to preserve by law, marine historic assets of national importance. There is no requirement for specific permission to carry out work inside a Historic MPA, however permission under the Town and Country (Scotland) Planning Act (1997) or a Marine Licence (ML) under the Marine and Coastal Access Act (MCCA) 2009 (in waters 12 nm to 200 nm), or under the Marine (Scotland) Act 2010 (from Mean High Water Springs (MHWS) to 12 nm) may be required (content available on the United Kingdom (UK) Government Website accessed August 2022 legislation.gov.uk).
12. Clear preservation objectives are provided for each Historic MPA and their boundaries define an exclusion zone to activities that could lead to disturbance of the marine historic asset.
13. In Scotland, the Marine Scotland Act 2010 has replaced Section 1 of the Protection of Wrecks Act 1973.

2.1.3. Protection of Wrecks Act 1973

14. Section 2 of the Protection of Wrecks Act 1973 (content available on the UK Government Website accessed August 2021 legislation.gov.uk) provides guidance on the protection of wrecks that are designated as dangerous due to their contents. Protections are administered by the Maritime and Coastguard Agency (MCA) through the Receiver of Wreck (RoW).

2.1.4. Protection of Military Remains Act 1986

15. The Protection of Military Remains Act 1986[2] makes it an offence to interfere with the wreckage of any crashed, sunken or stranded military aircraft or designated vessel, without a licence. This is irrespective of whether there was loss of life associated with the wreck, or whether the loss of the aircraft or vessel occurred during peacetime or wartime.
16. All crashed military aircraft receive automatic protection under this Act, but vessels must be individually designated. There are two levels of protection offered by this Act:

• designation as a Protected Place: Protected Places include the remains of any aircraft which crashed while in military service or any vessel designated (by name, not location) which sank or stranded in military service after 04 August 1914. Although crashed military aircraft receive automatic status as a Protected Place, vessels need to be specifically designated by name. The location of a vessel does not need to be known for it to be designated as a Protected Place; and
• designation as a Controlled Site: Controlled Sites are designated areas which encompass the remains of military aircraft or a vessel sunk or stranded in military service within the last 200 years. Diving operations are effectively prohibited in these sites without a specific licence granted by the Secretary of State in accordance with the provisions of the Act.

2.1.5. Ancient Monuments and Archaeological Areas Act 1979

17. This primarily land-based Act also provides protection for underwater sites within the UK territorial waters. Buildings, structures or works, caves or excavations, vehicles, vessels, aircraft or other movable structures of national importance may be scheduled as ‘monuments’. It is an offence to demolish, destroy, remove, alter or repair or make any alterations to a monument or carry out any flooding or tipping operations, without scheduled monument consent (content available on the UK Government Website accessed August 2022 - legislation.gov.uk). The Act is administered in Scotland by HES on behalf of Scottish Ministers.

2.1.6. Merchant Shipping Act 1995

18. All wrecks within UK territorial waters and any wreck which landed in the UK from outside the UK territorial waters must, as stated in Section 236 of the Merchant Shipping Act 1995, be declared to the RoW, who acts on behalf of the MCA in administering this section of the Act. The Act defines ‘wreck’ as anything which is found in or on the sea or washed ashore from tidal waters (content available on the UK Government Website accessed August 2022 legislation.gov.uk).
19. All items which are raised from the seabed, regardless of age or importance, must be reported to the RoW who will act to settle questions of ownership and salvage. Finders who report their finds to the RoW have salvage rights.

2.1.7. International Law

20. Outside the UK territorial waters (i.e. beyond 12 nm), the regulation and reporting of maritime archaeology is governed by international legislation and guidance, such as the United Nations Convention on the Law of the Sea 1982 (UNCLOS, 1982), the European Convention on the Protection of the Archaeological Heritage (Revised) 1992 (the Valletta Convention) and the United Nations Educational, Scientific and Cultural Organisation’s Convention on the Protection of Underwater Cultural Heritage 2001 (UNESCO, 2001).

2.2. Planning Framework

2.2.1. Marine Policy Statement 2011

21. The UK Marine Policy Statement (MPS) sets out high level marine objectives for ensuring that marine resources are used in a sustainable way. It was published by the UK Government in 2011.
22. Section 2.6.6 of the MPS sets out the aspects of the historic environment that merit consideration in marine planning and advises that heritage assets should be conserved through marine planning in a manner appropriate and proportionate to the significance of the asset. When considering the significance of a heritage asset and its setting, the marine planning authority should take into account the particular nature of the interest held in the asset and the value it might hold for this and future generations.
23. Designated heritage assets in coastal/intertidal zones and inshore/offshore waters may include Scheduled Monuments, Protected Wreck Sites and sites designated under the protection of the Military Remains Act 1986. Non-designated heritage assets of equivalent status should be considered under the same policy principles as designated heritage assets.
24. Where the loss of the whole or material part of a heritage asset’s significance is justified, suitable mitigation measures should be put in place. Mitigation requirements should be based on advice from relevant regulators and advisors.

2.2.2. Scotland’s National Marine Plan 2015

25. The Scottish National Marine Plan (NMP) was published in 2015 and reviewed in 2018 and 2021 and sets out high-level objectives for managing offshore development and advise for the preparation of future Regional Marine Plans.
26. General Policy 6 within the National Marine Plan relates to the historic environment and states that ‘Development and use of the marine environment should protect and, where appropriate, enhance heritage assets in a manner proportionate to their significance’.
27. The NMP advises that designated heritage assets should be protected in situ within an appropriate setting, and that substantial loss of harm to designated assets should be exceptional and should only be permitted ‘if this is necessary to deliver social, economic or environmental benefits that outweigh the harm or loss’.
28. The NMP further identifies that non-designated heritage assets that meet designation criteria or make a positive contribution should also be protected in situ, wherever possible, and consideration given ‘to the potential for new discoveries of historic or archaeological interest to arise’.
29. The NMP outlines that proposals for development that may ‘affect the historic environment should provide information on the significance of known heritage assets and the potential for new discoveries to arise. They should demonstrate how any adverse impacts will be avoided, or if not possible, minimised and mitigated. Where it is not possible to minimise or mitigate impacts, the benefits of proceeding with the proposal should be clearly set out’.
30. The NMP also states that ‘where the case for substantial change to heritage asset is accepted, marine decision-making authorities should require applicants to undertake suitable mitigating actions to record and advance understanding of the significance of the heritage asset before it is lost, in a manner proportionate to that significance’.

2.2.3. Regional Marine Plan

31. The Proposed Development lies within the Forth and Tay region as defined by the Scottish Marine Regions Order 2015 (legislation.gov.uk). The regional marine plan for the Forth and Tay region is still at the very early stages of development.

2.2.4. Marine Archaeological Guidance

32. Guidance which has been considered in the production of this Marine Archaeology Technical Report includes:

• Code of Conduct (Chartered Institute for Archaeologists, 2014);
• Standard and Guidance for Historic Environment Desk Based Assessment (Chartered Institute for Archaeologists, 2014);
• The Code of Practice for Seabed Developers (The Joint Nautical Archaeology Policy Committee, 2008);
• Historic Environment Guidance for the Offshore Renewable Energy Sector (COWRIE, 2007);
• Offshore Renewables protocol for Archaeological Discoveries (The Crown Estate, 2014);
• Offshore Geotechnical Investigations and Historic Environment Analysis: Guidance for the Renewable Energy Sector (Gribble and Leather, 2010); and
• Making the Most of Scotland’s Seas (The Scottish Government, 2010).

3. Methodology for defining the baseline environment

3.1. Scope

33. The scope of this study is to:

• assess the results of the 2019 and 2020 geophysical survey datasets provided by Fugro Consultants (2019, 2020a 2020b) (Fugro) to identify any sites and materials of possible archaeological significance within the marine archaeology study area; and
• compare the geophysical interpretation with the desktop review, historical data, known archaeological sites and previous investigations in the vicinity of the marine archaeology study area to outline the known and potential marine archaeological resource.
  34. Marine archaeology as assessed in this report is characterised as:
• submerged prehistoric archaeology (for example, palaeochannels and other features that contain prehistoric sediment, and derived Palaeolithic artefacts e.g., hand axes); and
• maritime archaeology (such as shipwrecks and associated material including cargoobstructions and fishermen’s’ fasteners) and aviation sites (aircraft crash sites and associated debris).

3.2. Marine Archaeology Study Area

35. The marine archaeology study area encompasses the Proposed Development array area and Proposed Development export cable corridor up to MLWS at the selected landfall (Skateraw Landfall). The Proposed Development array area together with the Proposed Development export cable corridor comprise the Proposed Development site. Geophysical survey was undertaken over the Geophysical Survey Area (GSA) indicated in Figure 3.1   Open ▸ which covers the Proposed Development array area and a representative portion of the Proposed Development export cable corridor. Where the GSA extends beyond the Proposed Development export cable corridor an assumption can be made for a similar corresponding result within the Proposed Development export cable corridor itself. The marine archaeology study area is defined as the Proposed Development site plus an additional 2 km buffer area around the extent of the Proposed Development site. This was used as the search area within which records from relevant archive databases were obtained. This wider marine archaeology study area allows for a greater understanding of the wider archaeological baseline environment, with the dual purpose of enabling any archaeological trends within the region to be recognised and to allow any archaeological sites identified to be represented in a broader archaeological context.
36. The marine archaeology study area overlaid onto Admiralty Chart is shown in Figure 3.2   Open ▸ .

Figure 3.1: Geophysical Survey Area Relative to the Marine Archaeology Study Area

3.2.2. Desktop Review

37. Information on marine archaeology within the marine archaeology study area was collected through a detailed desktop review of existing studies and datasets from the following principal primary sources:

• records of UK Hydrographic Office (UKHO) wrecks and obstructions;
• records of MPAs held by HES in their online Historic Environment Portal;
• catalogue of heritage sites recorded on the National Record of the Historic Environment held by HES and accessed via their website called Canmore;
• records held in East Lothian Historic Environment Record; and
• records held in Scottish Borders Historic Environment Record.
  38. The baseline data were plotted to identify the general distribution of known and recorded shipping casualties within the marine archaeology study area. Information drawn from secondary sources was used qualitatively, particularly to develop an understanding of the likelihood of unknown and unrecorded maritime archaeological sites.
  39. Records of Second World War Air/Sea Rescue Operations cited by Wessex Archaeology (2008) were used with a documentary review of historic aviation activity in the region, to understand the density and general distribution of wartime aircraft activity in the marine archaeology study area and thus highlight the potential for the presence of aircraft crash sites.

3.2.3. Site-specific Surveys

40. The potential for submerged prehistoric archaeology is assessed with reference to seabed geology and topography, which has been informed by a combination of sources, including peer-reviewed literature but principally, geophysical survey data. A geophysical survey was undertaken across the GSA. Magnetometer, Sidescan Sonar (SSS), Sub-Bottom profiler (SBP) and Multibeam Bathymetry (Multibeam Echosounder; MBES) survey data were collected by Fugro between August and October 2019 (Fugro 2019, Fugro 2020a and 2020b). The primary purpose of these data was to inform the potential for submerged prehistoric archaeology and anomalies of potential anthropogenic origin requiring consideration to be present within the marine archaeology study area and provide baseline information to inform the EIA of the Proposed Development ( Figure 3.2   Open ▸ ).
41. The data collected varied in specification however, it is considered comparable and appropriate to allow for the characterisation of the marine archaeological potential of the Proposed Development site. The full scope and methods for these investigations are described in the method statements produced in advance of each geophysical and geotechnical survey.
    

Figure 3.2:  Marine Archaeology Study Area Overlaid onto Admiralty Chart

42. Line spacing within the Proposed Development array area and the areas surveyed within Proposed Development export cable corridor varied. Within the Proposed Development array area the specification was set at 200 m for mainlines (running north north-west/south south-east) with crosslines (running WSW/ENE) at 1000 m; whilst within the Proposed Development export cable corridor mainlines were specified at 75 m with crosslines at 1000 m.
43. The data was collected to a specification appropriate to achieve the following interpretation requirements:

• magnetometer: identification of contacts > 5 nano Tesla (nT);
• SSS: ensonfication of contacts > 0.3 m;
• SBP: penetration > 10 m; and
• MBES: ensonification of contacts < 1.0 m.
  44. Following data delivery, an initial review of the dataset was undertaken to gain an understanding of the geological and topographic make-up of the survey area. Within the survey area, the potential for variations in the seabed are high and can affect the interpretation of contacts. However, the towed sensors, SSS and magnetometer, used an Ultra Short Baseline (USBL) positioning system to ensure positional accuracy of the sensors throughout the survey. Positional accuracy is further increased through the correlation of SSS and Magnetometer datasets with the MBES dataset.
  45. SSS is considered the best tool for the identification of anthropogenic contacts on the seabed through its ability to ensonify small features and so forms the basis of any archaeological data assessment.
  46. Magnetometer data indicate the presence of ferrous and thus usually anthropogenic material both on, and under the seabed, and where line spacing allows. The survey line spacing for the site-specific geophysical survey ranges between 75 m and 200 m which is too great for the accurate positioning of magnetic anomalies but can indicate areas of archaeological potential. A magnetic anomaly position can only be determined from directly below the sensor, or where lines are run close together to position an anomaly seen on two, or more lines. Where possible, significant magnetic anomalies were correlated with contacts visible on the seabed.
  47. Whilst SBP and MBES are useful tools for archaeological assessment, their primary use, outside of seabed and palaeo-landscape characterisation, is in the corroboration of contacts identified in the SSS and magnetometer data. As such, all contacts of potential anthropogenic origin were assessed for archaeological potential, primarily alongside the magnetometer data, with SBP and MBES data used to corroborate identified contacts.
  48. Archaeological potential was assigned to each contact based on the criteria outlined in Table 3.1   Open ▸ below. Where uncertainty existed as to the identification or archaeological potential of a contact the provided dataset was imported into point cloud visualisation software such as Cloud Compare to view the un-gridded data.

Table 3.1: Criteria for Assigning Archaeological Potential

49. Contacts assessed as having low, medium and high archaeological potential were then compiled into a gazetteer and a shapefile created for further assessment alongside known features such as wrecks, mooring buoys, third party assets such as cables and pipelines, and other seabed structures. The data was subsequently assessed against known anomalies of no archaeological interest to remove contacts of no archaeological importance.
50. As well as identifying surface contacts of potential archaeological interest the geophysical and hydrographic survey data was reviewed to assess the potential survival of palaeo-landscapes within the marine archaeology study area.
51. Sub-surface data acquired from SBP and seismic surveys is key to understanding the palaeo-landscape potential of the marine archaeology study area. Sedimentary horizon grids and geological maps derived from the interpretation of sub-surface data and the current seabed derived from MBES data were assessed. Sedimentary deposits were correlated with geological formations, and the depositional context and make-up of the deposits presented. The results inform the characterisation of the palaeo-environmental and archaeological potential included in this report.

3.2.4. Data Limitations

52. The interpretation of geophysical and hydrographic data is by its very nature, subjective. However, by using an experienced specialist who can analyse the form, size and characteristics of an anomaly, a reasonable degree of certainty can be achieved. Measurements can be taken in most data processing software, and whilst largely accurate, discrepancies can occur. Where there is uncertainty as to the potential of an anomaly or its origin, a precautionary approach is always taken to ensure the most appropriate mitigation for the historic environment is recommended. There may be instances where a contact may exist on the seabed but not be visible in the geophysical data. This may be due to the anomaly being covered by sediment or being obscured from the line of sight of the sonar, or due to poor quality data. The use of both SSS and MBES data mitigates this by visualising anomalies from many angles.