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Triton Knoll Offshore Wind Farm Limited
TRITON KNOLL ELECTRICAL SYSTEM
Environmental Statement
Non-Technical Summary
April 2015, Revision A
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Triton Knoll Offshore Wind Farm Limited
Triton Knoll Electrical System
Environmental Statement
Non-Technical Summary
April 2015
Drafted By: GoBe Consultants Ltd.
Approved By: Kim Gauld-Clark
Date of Approval April 2015
Revision A
COPYRIGHT © 2015 Triton Knoll Offshore Wind Farm Limited
All pre-existing rights reserved
Triton Knoll Offshore Wind Farm Ltd
Auckland House
Great Western Way
Swindon
Wiltshire, SN5 8ZT
T +44 (0)845 720 090
F +44 (0)845 720 050
I www.rweinnogy.com/tritonknoll
Liability
In preparation of this document Triton Knoll Offshore Wind Farm Limited (TKOWFL), a joint venture between RWE Innogy UK (RWE) and Statkraft UK, and subconsultants working on behalf of TKOWFL have made reasonable efforts to ensure that the content is accurate, up to date and complete for the purpose for which it was prepared. Neither TKOWFL nor their subcontractors make any warranty as to the accuracy or completeness of material supplied. Other than any liability on TKOWFL or their subcontractors detailed in the contracts between the parties for this work neither TKOWFL or their subcontractors shall have any liability for any loss, damage, injury, claim, expense, cost or other consequence arising as a result of use or reliance upon any information contained in or omitted from this document.
Any persons intending to use this document should satisfy themselves as to its applicability for their intended purpose. Where appropriate, the user of this document has the obligation to employ safe working practices for any activities referred to and to adopt specific practices appropriate to local conditions.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Table of Contents
1 INTRODUCTION ........................................................ 1
2 LEGISLATION AND POLICY ...................................... 5
3 ENVIRONMENTAL IMPACT ASSESSMENT METHODOLOGY ........................................................ 7
4 SITE SELECTION ..................................................... 10
5 THE PROPOSED DEVELOPMENT ......................... 13
6 OFFSHORE EFFECTS ............................................. 19
7 ONSHORE EFFECTS .............................................. 33
8 POTENTIAL FOR INTER-RELATED EFFECTS ....... 45
9 POTENTIAL FOR CUMULATIVE EFFECTS ............ 45
10 POTENTIAL FOR TRANSBOUNDARY EFFECTS ... 45
11 CONCLUSIONS........................................................ 45
12 FURTHER INFORMATION ....................................... 46
Triton Knoll Offshore Wind Farm Limited have been awarded EU TEN-E funding to support the development of the Triton Knoll Offshore Wind Farm Electrical System located in both UK Territorial waters and the UK’s Exclusive Economic Zone. The funding which is to be matched will support a number of surveys, engineering reports, and environmental impact assessment studies for the Triton Knoll Electrical System. The studies will form part of the formal documentation that will accompany the Development Consent Order which will be submitted to the Planning Inspectorate. The sum of €1,159,559 has been granted and the process to reclaim this funding is ongoing.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Acronym Full Term
AIS Air-insulated switch gear
CoCP Code of Construction Practice
CEMP Construction Environmental Management Plan
DCO Development Consent Order
EIA Environmental Impact Assessment
ES Environmental Statement
GIS Gas-insulated switch gear
HDD Horizontal Directional Drilling
HVAC High voltage alternating current
IEC Intermediate Electrical Compound
km Kilometre
MHWS Mean High Water Springs
MLWS Mean Low Water Springs
MMO Marine Management Organisation
MW Megawatts
NGET National Grid Electricity Transmission
NPS National Policy Statement
NSIP Nationally Significant Infrastructure Project
NTS Non-Technical Summary
PEI Preliminary Environmental Information
PINS The Planning Inspectorate
PRoW Public Right of Way
TWOWF Triton Knoll Offshore Wind Farm
TWOWFL Triton Knoll Offshore Wind Farm Ltd
TCE The Crown Estate
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
1 INTRODUCTION
Overview
1.1 Triton Knoll Offshore Wind Farm Ltd (TWOWFL) is proposing to develop the Triton Knoll Electrical System (the ‘proposed development’) in order to connect the Triton Knoll Offshore Wind Farm (TKOWF)1, for which consent was granted by the Secretary of State in July 2013, to the existing National Grid substation at Bicker Fen, Boston, Lincolnshire.
1.2 This document is the Non-Technical Summary (NTS) of the Environmental Statement (ES) for the proposed development. This NTS provides information about the proposed development, the studies undertaken and a summary of the anticipated effects of the project based on the findings of the Environmental Impact Assessment (EIA) undertaken.
1http://www.rwe.com/web/cms/en/413712/rwe-innogy/sites/wind-offshore/developing-sites/triton-knoll/the-offshore-array/
1.3 For more detailed information, readers should consult the full ES which is divided into three main volumes, with an additional two volumes of annexes:
• Volume 1: Introductory chapters
• Volume 2: Offshore chapters
• Volume 3: Onshore chapters
• Volume 4: Offshore technical annexes
• Volume 5: Onshore technical annexes
1.4 Details on how to access the full ES and the other accompanying application documents are provided at Section 12 of this NTS.
The Applicant
1.5 TKOWFL is a joint venture between two leading international energy companies; RWE Innogy UK Ltd and Statkraft UK. RWE Innogy UK Ltd is the UK subsidiary of the German renewable energy company RWE Innogy (part of RWE AG), a company with a strong and diversified position in renewable energy development. Statkraft UK is a subsidiary of Statkraft Group, Europe’s largest generator of renewable energy and is the leading power company in Norway.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
1.6 Both partner companies are committed to developing and operating wind farms and hydro plant to generate sustainable electricity and are highly experienced in offshore wind farm development.
1.7 RWE Innogy UK currently operates 19 hydroelectric schemes and 26 offshore and onshore wind farms in the UK. In 2004 they completed the construction of the UK’s first major offshore wind farm, North Hoyle, off the coast of North Wales.
1.8 RWE Innogy UK’s offshore projects include:
• North Hoyle, North Wales – 30 turbines (60 megawatts (MW) capacity);
• Rhyl Flats, North Wales – 25 turbines (90 MW capacity), operational since 2009;
• Greater Gabbard, Suffolk – 140 turbines (504 MW capacity), operational since 2012. This is a 50% joint venture with Scottish and Southern Energy;
• Gwynt y Mór, North Wales – 160 turbines (576 MW capacity), first generation achieved in August 2013 and the wind farm became fully operational in 2015; and
• Galloper, Suffolk – number of turbines to be determined for up to 340 MW capacity; offshore construction scheduled to start in 2016.
1.9 Statkraft is a leading company in hydropower internationally and Europe’s largest generator of renewable energy. Statkraft’s renewable energy generation assets have a capacity of 900 MW and the company is the majority owner and operator of three onshore wind farms, a major shareholder in two offshore wind farms, and owns and operates the largest hydropower plant in England and Wales.
1.10 Since 2009, Statkraft has been working towards becoming a lead developer in all phases of the project life cycle. In 2014 Statkraft took over the operation of for the 317 MW Sheringham Shoal offshore wind farm. In July 2014 Statkraft, in partnership with Statoil (as operator) and Masdar, made an investment decision on the 402 MW Dudgeon offshore wind farm in the Greater Wash.
1.11 RWE Innogy UK and Statkraft UK are part of the Forewind Consortium currently developing the proposed Creyke Beck and Teesside Offshore Wind Farms within the Dogger Bank Zone (combined generating capacity of up to 4.8 GW).
Project Overview
1.12 The Triton Knoll Electrical System will connect the consented Triton Knoll Offshore Wind Farm array to the
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
national grid at Bicker Fen, Lincolnshire. The location of the project is shown on Figure 1-1.
1.13 The project comprises the following main components:
• Submarine cable route for exporting electricitygenerated by the offshore wind farm to the shorealong a route of around 66 km;
• A landfall site with associated jointing of offshoreand onshore cables to the north of the village ofAnderby Creek;
• Onshore underground cable along a route ofaround 60 km;
• An Intermediate Electrical Compound, east of thevillage of Orby;
• A new onshore substation for TKOWF to the northwest of the village of Bicker; and
• A connection to the existing National Gridsubstation at Bicker Fen.
1.14 A grid connection agreement was signed between TKOWFL and National Grid Electricity Transmission (NGET) in 2012. This identified the connection point as the existing 400 kV substation at Bicker Fen.
1.15 If the application is successful, construction is anticipated to commence in 2017.
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© Crown copyright, All rights reserved. 2014 License No. EK001-20140601. Contains Ordnance Survey data © Crown copyright and database right 2014. Not to be used for navigation.
Figure 1-1Location of the proposed Triton Knoll
Electrical System project
SCALE: @ A3
Source: Global Land Cover Facility, www.landcover.org.
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Coordinate System: British National Grid
Projection: Transverse Mercator
Datum: OSGB 1936
Units: Meter
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Triton Knoll Intermediate Electrical Compound
Triton Knoll Cable Landfall
Triton Knoll Substation
Bicker Fen NGET Substation
East Lindsey District
West Lindsey District
North Kesteven District
Boston District (B)
South Holland District
North Norfolk DistrictKing's Lynn and West Norfolk District (B)
South Kesteven District
North East Lincolnshire (B)North Lincolnshire (B)
Lincoln District (B)
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Ordnance Survey (2014)
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Rev Date Description Drn
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TKOWF Array
!( National Grid Connection
Administrative Boundary(District/Borough)
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Purpose of the Environmental Statement
1.16 The ES has been prepared in order to assess the likely significant effects of the proposed development on the environment. The scope of the ES includes both the offshore and onshore elements of the Triton Knoll Electrical System.
1.17 Section 2 of this NTS provides an outline of the consents process, followed by an outline of the approach to the impact assessment (Section 3) and an overview of the site selection process for the project (Section 4).
1.18 A description of the project is provided in Section 5, followed by an overview of the environmental effects on the offshore and onshore elements in Sections 6 and 7.
1.19 Consultation regarding the project has been ongoing. Preliminary Environmental Information (PEI) was produced in September 2014 for the statutory consultation carried out under sections 42 and 47 of the Planning Act 2008 in October/November 2014. Feedback from the consultation processes has been taken into account and, where appropriate and practicable, has been used to amend and improve the proposed development and the final ES.
1.20 The ES and this NTS accompany the application made for development consent for the Triton Knoll Electrical System. Details of how consultees and members of the public may respond to the application, together with details of how to register as an interested party, can be found on the Planning Inspectorate website at:
http://infrastucture.planningportal.gov.uk
2 LEGISLATION AND POLICY
Renewable energy policy overview
2.1 The United Kingdom Government has concluded that there is a strong need for offshore wind generation. This is required to meet international climate change obligations and European and domestic targets for renewable energy, as well as replacing existing generating capacity reaching the end of its lifespan and ensuring security of supply to minimise reliance on imported energy.
2.2 During most of the industrial era, UK energy requirements have been met by both fossil fuels and nuclear energy. The UK Government has now set ambitious targets for renewable energy, including offshore wind.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
2.3 The 2010 National Renewable Energy Action Plan confirmed the UK’s commitment to source 15% of its energy from renewable sources by 2020, meeting the mandatory national target set under the Renewable Energy Directive at a European level.
2.4 While biomass, hydroelectricity and wave and tidal generation are all considered to have an important role to play, the Action Plan states that offshore wind is a key area for development and will play a pivotal role in meeting the 2020 target.
2.5 The UK’s commitment to renewable energy has been embodied in the National Policy Statements (NPS) for Energy, the requirement for which was set out by the Planning Act 2008. The relevant National Policy Statements for this application are the National Policy Statements for Energy (EN-1), Renewable Energy Infrastructure (NPS EN-3) and for Electricity Networks Infrastructure (NPS EN-5).
2.6 The need for offshore wind development is set out in both NPS EN-1 and NPS EN-3, with NPS EN-3 specifically noting the following:
‘offshore wind farms are expected to make up a significant proportion of the UKs renewable energy generating capacity up to 2020 and towards 2050’
The Consenting Process
2.7 Applications for development consent for Nationally Significant Infrastructure Projects (NSIP) relating to energy are made to the Secretary of State for Energy and Climate Change. Although the proposed Triton Knoll Electrical System development would not constitute an NSIP in its own right2, to enable the onshore and offshore elements of the system to be progressed through a single application to a single decision-maker, the Secretary of State confirmed on 14th November 20133 that the proposals should be treated as development requiring development consent under the Planning Act 2008. If granted, consent to build and operate the proposed Triton Knoll Electrical System development will therefore take the form of a Development Consent Order (DCO). DCO applications are examined by the Planning Inspectorate, before the final decision to grant or refuse consent is be made by the Secretary of State.
2 As defined in Section 15 of the Planning Act 2008 (http://www.legislation.gov.uk/ukpga/2008/29/section/15) 3 Direction made by the Secretary of State under Section 35 of the Planning Act 2008
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
2.8 The application provides for the project in its entirety, i.e. both onshore and offshore parts. For the offshore elements, a deemed marine licence is being applied for within the DCO application process, the terms of which have been drafted and discussed with the Marine Management Organisation (MMO) prior to the submission of the DCO application. This includes, for instance, any requirements for offshore environmental management and monitoring, as appropriate.
Environmental Impact Assessment
2.9 The process of Environmental Impact Assessment (EIA) applies to a DCO application. The requirements of the European Directive 2011/92/EU (the EIA Directive) are implemented by the Infrastructure Planning (Environmental Impact Assessment) Regulations 2009 (the EIA Regulations).
2.10 The ES and this NTS have been produced to provide information on the identification and assessment of the likely significant effects of the Triton Knoll Electrical System to accompany the development consent application. The ES is the overall document that contains full details of the proposals and the existing conditions, with the EIA being the section(s) of that ES that specifically address the potential for impact.
3 ENVIRONMENTAL IMPACT ASSESSMENT METHODOLOGY
Scoping
3.1 Scoping is the process of identifying the issues to be addressed during the EIA process. TKOWFL submitted a scoping report for the Triton Knoll Electrical System to the Planning Inspectorate in March 2014. This set out details of the proposed scope of environmental assessments to be undertaken for the proposed development.
3.2 The Secretary of State’s formal scoping opinion was received on 5th May 2014 (Application Document 8.1). The scoping exercise highlighted a number of areas that consultees wished to see addressed within the EIA. These responses, together with other consultation responses provided throughout the EIA process, have been taken into account in identifying the scope for the EIA. The scope has also been informed by the nature, size and location of the proposed development.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Consultation
3.3 Consultation is a key element of the Planning Act 2008 process. TKOWFL has been undertaking informal consultation with statutory bodies and other stakeholders on the Triton Knoll project since 2008, in order to identify and agree which issues are particularly relevant to the site and how those issues should be dealt with via the EIA process.
3.4 Landowners have also been consulted throughout the development process to inform the siting and route selection process.
3.5 With respect to formal community consultation, TKOWFL published its Statement of Community Consultation (SoCC) in September 2014 in local newspapers, setting out the proposed approach to the formal consultation process for the project.
3.6 The consultation process has used a range of communication tools, including the project website4, newsletters, briefings and questionnaires. In addition to
4http://www.rwe.com/web/cms/en/413708/rwe-innogy/sites/wind-offshore/developing-sites/triton-knoll/the-electrical-system/
those held previously, public exhibition events were held during October 2014.
3.7 Preliminary Environmental Information (PEI) in the form of a draft ES, together with a Non-Technical Summary, was produced in September 2014 for consultation with the local community under section 47 of the Planning Act 2008. The PEI documents also supported formal consultation under section 42 of the Planning Act.
3.8 TKOWFL has continued to address the issues raised and comments made throughout the EIA process and in finalising the application. The consultation process is summarised in the Consultation Report that accompanies the DCO application (Application Document 5.1).
Approach to EIA
3.9 The likely effects on the environment that may arise from the construction, operation, maintenance and decommissioning of the electrical system have been assessed in accordance with relevant EIA regulations and guidance.
Baseline Conditions
3.10 The existing and likely future environmental conditions in the absence of the project have been identified.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
These are known as ‘baseline conditions’. The baseline conditions of the site and study areas form the basis of each assessment, enabling the likely significant effects of the project to be identified.
Mitigation
3.11 The EIA process is an integral part of the project appraisal and design process. During the EIA, the likely significant effects have been identified and these issues have been taken into account within the ongoing design process. EIA has therefore been used as a means of informing and improving the project design.
3.12 The project assessed within the ES and for which the development consent application is made consequently includes a range of measures that have been designed to reduce or prevent significant adverse effects occurring. The assessment of effects has therefore taken these ‘embedded’ mitigation measures into account as they form part of the project itself.
Assessment of Effects
3.13 The ES sets out an assessment of the likely effects during all phases of the project based on the likely scale (magnitude) of the predicted impacts and the sensitivity of the affected receptor(s).
3.14 Given the necessary flexibility in the project design, the EIA has adopted an approach commonly referred to as the ‘Rochdale envelope’. This approach ensures that the worst case scenario is considered in order to determine the maximum potential environmental impacts that could result from the scheme.
3.15 Significance levels are defined separately for each topic using the terms major, moderate, minor or negligible. Unless identified otherwise, effects noted as being moderate or major are considered to be ‘significant’.
Cumulative Effects and Inter-relationships
3.16 The EIA Regulations require consideration of cumulative effects, which are effects on a receptor that may arise when the project is considered together with other proposed developments in the area. Cumulative effects are assessed and reported in each topic chapter of the ES.
3.17 The EIA Regulations also require consideration of inter-relationships between topics that may lead to environmental effects. For example changes in traffic flows may lead to changes in noise or air quality. An overall project assessment that considers the potential
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
for inter-related effects to occur has therefore been undertaken.
4 SITE SELECTION
4.1 The Triton Knoll Electrical System comprises a number of different onshore and offshore components. The siting and design of each of these components has been given very careful consideration and the principal reasons for the site selection of the various components is set out below.
Selection of connection point into the national grid
4.2 Work was undertaken jointly with National Grid to determine the appropriate connection point into the national grid. An extensive study was undertaken following the identification of an initial longlist of 12 connection points, including both existing and possible new National Grid substation sites across a study area that stretched from north Norfolk to the area immediately north of the Humber estuary.
4.3 Taking into account all relevant environmental, technical and commercial considerations, the existing National Grid Substation at Bicker Fen, near to Boston in Lincolnshire, was selected. The description of the
selection process that was undertaken and reasons for the selection of Bicker Fen are set out in detail in the Interface Selection Assessment Report (Application Document 8.18)
Selection of the offshore cable corridor
4.4 As part of the work described above to inform the selection of the national grid connection point, an extensive offshore characterisation exercise was undertaken. This identified a large number of constraints and therefore limited opportunities for offshore cabling routes.
4.5 An offshore cable corridor was subsequently selected that routed from the site of the consented Triton Knoll Offshore Wind Farm to a landfall area roughly in the centre of the Lincolnshire coastline. This route avoided key features, such as the Silver Pit (an important seabed feature) and also avoided other offshore wind farms and dredging areas.
Selection of the Landfall
4.6 A suitable cable landfall location is required at the coast including space for cable transition joint bays. A longlist of 17 potential landfall sites was drawn up within a
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
study area between Sandilands to the north and Gibraltar Point to the south.
4.7 Following extensive investigation, a shortlist of four landfall sites was identified including Anderby Creek North and Anderby Creek South. Anderby Creek North was eventually selected following a detailed comparison of the four sites, predominantly a result of having the lowest impact upon sensitive ecology and the ability to minimise the effect on access to the beach. It also represented the lowest engineering risk of the four shortlisted sites.
Selection of the Intermediate Electrical Compound
4.8 A suitable location for an Intermediate Electrical Compound (IEC) was required, approximately midway along the combined onshore and offshore cable route. An initial longlist of 29 sites was drawn up within a defined study area, by applying appropriate criteria.
4.9 Following further investigation, a shortlist of three sites was defined. Public consultation and discussions with the local planning authority were undertaken on these three sites in Spring 2013 and finally a site to the east of the village of Orby, to the north of Marsh Lane, was identified. Following this site selection, owing to a reduction of the size of the footprint of the site that was
required, it was possible to slightly re-locate the site to a smaller site to the south of Marsh Lane, in between two existing buildings (grain store and Skegness Stadium) to minimise visual intrusion into the countryside.
4.10 Following public consultation and discussions with the local Parish Councils, a decision was taken to amend the access route for Heavy Goods Vehicles during the construction period, to avoid high numbers of construction vehicles travelling through the village of Orby. Instead, large construction vehicles will access the site along a new temporary road from the A158 into the south of the IEC site. This road will be removed on completion of construction.
Identification of the onshore Cable Corridor
4.11 The onshore cable route was identified following the selection of the landfall at Anderby North, the IEC site to the east of Orby and connection to the national grid at Bicker Fen. The detailed design of the onshore cable corridor was undertaken to join up these sites in the shortest distance to minimise overall environmental effects, whilst also taking care to minimise effects on nearby residents, farming activities, sensitive archaeology and ecology.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
4.12 The site was routed to the south of Burgh le Marsh to avoid impacts upon National Trust land, The Wolds Area of Outstanding Natural Beauty and the National Trust Gunby Hall property. A public consultation exercise was undertaken in Spring 2014 on the proposed onshore cable corridor and this, together with the formal consultation on the PEI and responses from affected landowners have informed the final cable route within this application.
Selection of the new Triton Knoll Substation site
4.13 A suitable location for a new substation was required that was close to the connection point into the national grid. A study area was identified, which was the area within 5km of the existing Bicker Fen National Grid Substation, although land to the south of the railway line was excluded (which runs around 2 km to the south west of the existing substation).
4.14 A longlist of 19 sites was identified within this study area. After investigation, these sites were reduced down to a shortlist of four sites. A public consultation exercise was undertaken in Spring 2013 on the shortlisted sites, and detailed discussions were held with Boston Borough Council. Following these consultations, the Blue Zone was selected, immediately
to the east of the South Forty Foot drain (see Figure 4-1).
4.15 During public consultation, concern was expressed by residents of the nearby village of Bicker regarding the potential for high numbers of large construction vehicles to drive through the small roads within the village during the construction phase. A decision was subsequently taken to create a new permanent access road into the new substation from the A17. This will be used by all construction traffic for the new Triton Knoll substation and also will remain throughout the lifetime of the substation.
Further information
4.16 Further details of the studies, assessments, consultation undertaken in relation to site selection decisions are set out in detail in the Site Selection and Design Report (Application Document 8.17).
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Figure 4-1 Substation shortlist - zones
5 THE PROPOSED DEVELOPMENT
5.1 TKOWFL is planning the development of the TKOWF, located approximately 33 km (20.5 miles) east of the Lincolnshire coast (Figure 1-1). An application for consent for the offshore array (up to 288 turbines)
together with associated intra-array cabling and up to four offshore substations was made in January 2012. The Secretary of State granted a DCO on 12th July 2013. This NTS relates to the Triton Knoll Electrical System, which is required to connect the TKOWF offshore array with the national grid.
5.2 The Triton Knoll Electrical System has been progressed as a separate application from the TKOWF offshore array, as a result of uncertainty around the onshore interface point into the onshore national grid. Since then, an offer was made by National Grid Electricity Transmission (NGET) in January 2012 for connection to the existing substation at Bicker Fen. Following this offer, the proposals for the Triton Knoll Electricity System were subject to detailed study to optimise the project design, enabling the application for the Electrical System to be progressed.
5.3 A schematic of the proposed development is depicted in Figure 5-1, and can be summarised as follows:
• Up to six offshore high voltage alternating current (HVAC) power export circuits that will transmit the electricity generated by the TKOWF to the shore and across the beach to be joined with the onshore power cables. The export cables will run from the offshore substation platforms (OSPs),
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
located within the offshore array (and already consented), to the landfall. The offshore cables will therefore cross part of the array area. The exact length and route of the offshore cables will be dependent upon the location of the offshore substations but will be around 66 km in total;
• Offshore cable protection and pipeline crossings;
• Transition Joint Bays (TJBs) located to the north of Anderby Creek behind the beach and sand dunes where the offshore and onshore cables will be connected to each other;
• Up to six onshore HVAC power export circuits that will transmit electricity from the landfall to the proposed Substation (around 60 km);
• An Intermediate Electrical Compound (IEC) to the east of Orby;
• A Substation to the north-west of Bicker;
• Up to four onshore HVAC power circuits (up to 400 kV) that will transmit HVAC electricity from the Triton Knoll substation to the National Grid substation (a distance of around 1.8 km); and
• Unlicensed Works5 at the existing National Grid Bicker Fen substation comprising up to two new ‘bays’ of electrical equipment required to connect to the national grid.
Figure 5-1 Triton Knoll Electrical System Schematic
5 “Unlicensed works” are electrical works needed to connect Triton Knoll to the National Grid substation at Bicker Fen that National Grid is not required pursuant to its transmission licence to carry out itself.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Offshore
5.4 Preparatory works, undertaken prior to the offshore cables being installed, may include surveys to identify surface debris, unexploded ordnance and seabed features, clearance of surface debris and removal of the crests of sandwaves.
5.5 The offshore export cables, each with a total length of approximately 66 km, will be buried where it is reasonably feasible to do so. They will be protected where burial is not feasible, to prevent the movement of the cables, limit potential environmental impacts and to avoid risks to other marine users. Cables will be laid in sections using one or a combination of the following methods:
• Ploughing, where the cable is simultaneously laid and buried. Typically the cable plough lifts a section of the seabed deposit and lays the cable below it. The seabed deposit is then returned to its original position. Some variation in the ploughing process may be required to take account of the type and form of seabed sediment;
• Jet trenching, where the cable is laid on top of the seabed and a remotely operated vehicle moves along the cable route using high pressure water
jets to fluidise the seabed around the cable allowing it to sink and be buried; and
• Mechanical trenching, where a trench is cut into the seabed using a machine with a cutting chain or wheel, with the cable being laid into the trench. This option may be needed where stiff clay or rock is present.
5.6 The final choice of installation methods will be made at the detailed design stage and informed by the nature of the seabed present along the cable route. It is expected that ploughing will be the main technique used.
5.7 The offshore cables will extend across the beach where they will be buried within a trench of an adequate depth to ensure that they remain buried.
Landfall
5.8 To minimise disturbance to the surface at sensitive locations, special techniques will be used to pass the cable underground. There are three types of these ‘trenchless’ techniques proposed:
• Horizontal Directional Drilling (HDD);
• Pipe-jacking (horizontal auger boring); and
• Micro-boring.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
5.9 At the landfall, a trenchless technique will be used to pass beneath the sea defences, a method which will also avoid impacting sand dunes at Anderby (see Fig 5-2). The cables will be installed in ducts below the sea defences.
Figure 5-2 Schematic of the HDD process at landfall
5.10 At the end of the operational life of the project, the offshore cables may be removed in line with seabed leasing arrangements with The Crown Estate (TCE). Any such decommissioning would be agreed with TCE and the Department of Energy and Climate Change and in accordance with relevant guidance, legislation and good practice in place at that time.
5.11 Further details of the cable installation options are provided in the Project Description chapters of the ES (Chapter 1 of Volume 2 (offshore) and Volume 3 (onshore).
Onshore
5.12 The onshore development will include the cable landfall to the north of Anderby Creek and the onward cable route from the landfall location to the Triton Knoll substation adjacent to the existing National Grid substation at Bicker Fen via the IEC, east of the village of Orby.
5.13 The onshore cable route is approximately 60 km in length from the landfall to the substation. A new substation will be required close to the existing substation at Bicker Fen to change the voltage coming in from the offshore wind farm to the voltage distributed via the national grid.
5.14 The landfall and cable laying activities will be temporary and land within these construction areas will be reinstated after construction, with hedgerows replanted. The IEC and substation will be operational structures which will remain in place during the life of the project.
5.15 Further details of the onshore development proposals are provided in the ES (Volume 3; Chapter 1).
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Cables
5.16 The cables will be buried underground within pre-laid cable ducts. The ducts will be laid within trenches, apart from where the cables are installed underground using trenchless techniques. As noted above, these techniques will be used at the landfall but also to pass under various features such as roads and larger water courses to avoid closures or impacts occurring6. One cable circuit will be placed in each trench, therefore if six cable circuits are used up to six trenches will be needed.
5.17 Cables will be supplied and installed in lengths and these will be joined together via jointing bays that will be relatively evenly spaced along the 60 km onshore route. “Link boxes” will be required at each joint bay to allow access for any testing or repair of cable that might be required7.
6 TKOWFL has committed to use trenchless techniques to cross all public roads and also all water courses that are owned/maintained by the Environment Agency, Canal and River Trust or any Internal Drainage Board. The locations where trenchless techniques have been committed to are set out in the Crossing Schedule (Application Document 8.3) 7 Link boxes will consist of a manhole set in a concrete plinth at ground level
5.18 The cable route construction corridor will be fenced from livestock and public access, with appropriate crossing points available for landowners, livestock and public rights of way (PRoW). Topsoil and subsoil will be removed and stored separately within the corridor area, which is typically up to 60 m wide8. This corridor width allows for the cable trenches, a temporary construction (haul) road and storage for the soils. An indicative construction corridor cross section is shown in Figure 5.3.
8 While the majority of the cable corridor will be 60 m, approximately 3 km of the cable corridor from the A158 north to the IEC will have a maximum width of 66 m to allow for a double-width haul road to accommodate IEC plant delivery and installation traffic, thus removing it from local minor roads
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Figure 5.3 Indicative construction corridor cross section
IEC and Substation
5.19 The IEC and substation will comprise a range of electrical equipment, some of which will be located externally within the compounds, with other sensitive equipment housed within buildings. The IEC building will have a maximum height of 13 m, with the substation building reaching a maximum of 13 m (depending on the technology selected)9.
9 The infrastructure within the Substation compound will include either air-insulated switchgear or gas-insulated switchgear. The choice of switchgear
5.20 An outline landscape strategy has been developed for these sites in order to screen the development area as far as possible (Application document 8.8).
Construction timetable
5.21 Onshore works are anticipated to start in 2017, with works completed by 2023. Construction of the offshore infrastructure is expected to commence in 2018, with
affects both the total land area required and the size and type of buildings which will be present. This will be part of the detailed design process and a decision will be made post-consent prior to construction commencing.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
installation anticipated to take up to 12 months, spread across a two year period. Offshore cable installation works are typically carried out in relatively calm conditions which would likely therefore involve summer working, although some construction activities could take place throughout the year.
6 OFFSHORE EFFECTS
Marine Physical Environment
6.1 The assessment of potential impacts on the offshore physical environment considers the potential for a change in the tides, currents, waves and sediment transport as a result of the proposed development. Within the ES, this assessment has focused on the potential impacts to features identified during the scoping exercise and consultation as being sensitive to the construction, operation or decommissioning of the Triton Knoll Electrical System. Full details of the baseline environment against which the assessment has been carried out can be found in Volume 4; Annex 2-1, with the EIA presented in Volume 2; Chapter 2.
6.2 The features considered include designated seabed and intertidal areas as well as other areas such as sandbanks and beaches around the landfall.
6.3 The assessment has been based on previous detailed surveys and data on the existing baseline environment, with the use of detailed modelling of tides, waves and sediment plumes to identify and assess predicted impacts.
6.4 A number of measures have been embedded within the project design, to provide mitigation of potential impacts. These include selection of the landfall point, careful routing of the offshore cable route to avoid designated seabed or features such as sandwaves where feasible and a choice of construction equipment which minimises sediment disruption.
6.5 The range of potential impacts and associated effects considered has been informed by the detailed consultation undertaken as well as reference to existing policy and guidance. Those impacts considered include changes to the marine physical environment brought about directly (by the presence of infrastructure at the seabed), as well as indirectly (through a change to physical process).
6.6 During construction the following potential impacts have been assessed:
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
• A short-term increase in the amount of sediment in the water during the installation of cables, together with small-scale changes in seabed levels close to the works;
• Sandwave crest levelling, resulting in a change in local hydrodynamic, wave and sediment transport processes;
• Release of sediment and drilling fluid during drilling operations at the landfall;
• Temporary and localised impacts to the beach from sediment excavated from cable trenches before this material is used to refill the trenches; and
• Small alteration in water depth due to indentations in the seabed from vessel legs and anchors.
6.7 During the operational phase the following impacts have been considered:
• For the areas of cable protection, the potential for small scale, long-term change in the local hydrodynamic, wave and sediment transport processes; and
• Introduction of localised scour around the export cables and cable protection measures.
6.8 Impacts from decommissioning were identified to be comparable to, or lesser than, those predicted for the construction works.
6.9 The EIA concluded that for the assessment of physical processes, the potential for impact in all cases, including cumulative effects, was not significant.
Seabed habitats and animals
6.10 The ES describes the marine animals and habitats found on the seabed and the shore, with the potential for impact to these identified and assessed. The assessment uses information from a range of detailed studies, project specific survey (including work undertaken for the TKOWF, together with seabed surveys of the cable route) and technical reports, as well as other scientific literature. Full information on the baseline against which the assessment has been carried out is available in Volume 4; Annex 4-1 and 4-2, with the EIA presented in Volume 2; Chapter 4.
6.11 The consultation process has clarified issues such as how the sensitivity to impacts of habitats and species should be defined and the way in which impacts should be assessed. The consultation process also confirmed which issues needed assessment in the ES, with these summarised below.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
6.12 A number of measures have been included in the project design as embedded mitigation to reduce or prevent potential impacts to the ecology. These include the route selection (which was aimed at avoiding areas important for nature conservation) and choice of proposed construction techniques. These are aimed at minimising disturbance to the seabed and release of sediment in areas where chalk is present on the seabed.
6.13 The main types of potential impact on marine animals and habitats relate to disturbance of the seabed during construction, the impact of an increase in suspended sediment in the water while installing submarine cables, drill fluid release in the intertidal area and the potential for animals to be covered by the sediment when it then settles back to the seabed.
6.14 Potential impacts during operation mainly relate to the loss of habitat underneath any cable protection that is used when the submarine cable cannot be buried and at pipeline crossings, together with any disturbance caused by maintenance vessels.
6.15 The outcome of the assessment of potential impacts on marine ecology is strongly linked to the type of habitat affected and how much of each habitat will be disturbed. The baseline surveys undertaken have found
that the habitats present are common to the southern North Sea and that impacts during construction will be localised and temporary. Potential impacts during operation, although these may last longer, affect a very small percentage of the overall area. For the majority of habitats, the effects are concluded to be negligible.
6.16 There are small areas of peat that occur in the intertidal area. In addition to being of nature conservation interest, the habitats that occur on peat are sensitive to habitat loss. However, even here, given that peat does not occur within the offshore cable corridor and any impacts will be small scale and temporary, the effect is predicted to be of no more than minor significance.
6.17 All impact effects, including those arising from decommissioning and when assessed cumulatively with other projects in the region, are therefore considered to be not significant.
Marine fish and shellfish
6.18 The consideration of fish and shellfish ecology in the ES is based on a detailed site specific study carried out for the Triton Knoll offshore wind farm as well as a review of available reports and surveys. Full details on the baseline against which the assessment has been
21
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
carried out are available in Volume 4; Annex 5-1, with the EIA presented in Volume 2; Chapter 5.
6.19 Fish and shellfish species of ecological importance are assessed along with those of specific commercial and nature conservation value.
6.20 A review of recreational fishing in the area was also carried out and reported in the ES. Information includes the main species caught, together with key fishing locations.
6.21 A number of mitigation measures for fish and shellfish ecology will be secured in the Project Environmental Management Plan (PEMP). The PEMP will address issues such as how construction work will be carried out responsibly and how information on activities will be communicated to users of the sea, e.g. planning for accidental spills. Other mitigation includes burial of submarine cables or, where this is not reasonably feasible, the use of cable protection material, both of which will mitigate against potential impacts such as electromagnetic fields (EMF).
6.22 The scope of potential impacts assessed in the ES has been agreed during consultation and includes the potential for direct damage to habitats or species, together with indirect impacts such as changes in the amount of sediment in the water during construction.
During operation, the potential impacts considered are EMF and physical habitat loss.
6.23 Direct damage during construction has the most potential to affect shellfish, which are less mobile than fish, and habitats which are important for spawning or for particular species such as sand eel.
6.24 The construction process will result in some sediment being released into the water. However, the levels of suspended sediments caused by the project are predicted to be within the range of those occurring naturally (for example during storms) and will persist for only a short amount of time. An increase in suspended sediment can potentially affect fish and shellfish by clogging the way they feed or by smothering habitats, eggs or larvae. The short duration and localised areas affected mean that overall, the potential for impact during construction is not considered to lead to significant effects.
6.25 During operation, the potential for EMF effects primarily relates to species which are sensitive to EMF, which include sharks, rays and some migratory species. As a result of the embedded mitigation measures for the project (burial or cable protection), any such impacts will be highly localised and no significant effects are predicted to occur.
22
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
6.26 The need for limited areas of cable protection and pipeline crossing points has the potential to impact fish and shellfish by the removal of small areas of habitat. As the area affected is a very small part of a much larger overall habitat and again no significant effects are predicted.
6.27 Impacts from decommissioning were identified to be comparable to, or lesser than, those predicted for the construction works and therefore similarly are not predicted to give rise to significant effects.
6.28 No significant cumulative effects were predicted to arise on fish or shellfish species or habitats.
Marine mammals
6.29 The consideration of marine mammals includes whales, dolphins, porpoise and seals. A number of data sources are available to describe the marine mammal species present in the area, including site specific surveys carried out for the TKOWF offshore array, work undertaken for other developments in the area and a number of regional and national studies. A desk-based review of these reports has been presented in the ES, within Volume 2, Chapter 6. The studies, together with the consultation process, confirm that the species likely
to be present in and around the cable corridor are harbour porpoise, grey seal and harbour seal.
Figure 6-1 Grey seal tracks between haul-out in the vicinity of the TKOWF
6.30 The potential for impact on marine mammals has been discussed during the scoping stage with consultees, with agreement reached that the risk is solely associated with the potential for injury resulting from collision or for animals to be pulled into ducted propellers, should these be used on vessels during construction, operation or decommissioning. The reason for this concern is that there are some reports of seals washing up on the shore with ‘corkscrew‘ injuries which may be connected to the use of such propellers,
23
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
although the most recent evidence suggests that the injures may actually result from adult male seals attacking seal pups. Even so, if vessels with ducted propellers are used for the project, TKOWFL would agree appropriate controls with regulatory authorities in line with guidance and best practice at the time.
6.31 The assessment identified the potential for impact in all cases, including cumulative effects, was not significant.
Birds
6.32 A large amount of data on the bird species present within the offshore study area, their numbers and distribution are available, primarily from the surveys and desk based studies previously undertaken as part of the assessment for the TKOWF offshore array, together with similar surveys completed for other offshore projects in the vicinity of the Order Limits within the southern North Sea and further datasets collected on a regional and national basis. In addition, site-specific intertidal bird surveys have been conducted at the cable landfall site. It was agreed with consultees during the Scoping phase of the TKES that, given the wealth of available data on birds at the site and more widely across the region, no further surveys were required. This information is summarised within the ES in Volume 2, Chapter 3.
6.33 As agreed during scoping consultation, the assessment of impact focuses on the potential for direct disturbance to birds during the construction phase, resulting from the increase in vessel traffic and construction activities in the intertidal area.
6.34 Although a number of the bird species present have a high or very high sensitivity to these kinds of disturbance, the limited area affected and the temporary nature of the work leads to a negligible significance in offshore areas. Close inshore and at the landfall, the occasional presence of common scoter leads to a minor significance of effect.
6.35 No impacts are predicted during operation of the Electrical System and impacts from decommissioning were identified to be comparable to, or lesser than, those predicted for the construction works. The potential for impact in all cases, including cumulative effects, was not significant.
24
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Figure 6-2 Gannet in flight
Nature conservation
6.36 There are a number of sites designated for marine nature conservation interest in the vicinity of the proposed project, including both coastal and offshore sites. During consultation, the sites that required assessment were highlighted, with these being noted below and shown in Figure 6-3. Full information is available in the ES, within Volume 2, Chapter 7. The habitats or species associated with these sites and which were assessed are given in brackets:
• The Wash Special Protection Area (cormorant and common scoter);
• North Norfolk Coast Special Protection Area (cormorant and common scoter);
• Humber Estuary Special Protection Area (cormorant);
• Inner Dowsing, Race Bank and North Ridge Site of Community Importance (potential Sabellaria reef and subtidal sandbanks)
• Chapel Point to Wolla Bank Site of Special Scientific Interest (intertidal sediments);
• Humber Estuary Special Area of Conservation (grey seal);
• Wash and North Norfolk Coast Special Area of Conservation (harbour seal);
• European Protected Species (harbour porpoise); and
• Habitats of nature conservation importance (reef features).
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Figure 6-3Designated Sites
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Humber Estuary SAC
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
6.37 The potential impacts during construction include temporary increases in the volume of sediment that is disturbed into the water column and then settling out back to the seabed, the loss or disturbance of habitat, disturbance of birds and risk of vessel collision for marine mammals. During operation, potential impacts assessed were small areas of habitat loss, the potential for a new habitat to form and the continued risk of vessel collision for marine mammals. Impacts from decommissioning were assessed as being comparable to, or lesser than, those predicted for the construction works.
6.38 The combination of the type and extent of potential impacts, the proposed mitigation (including for example avoiding sensitive areas and species), and the limited extent of potential impact areas means that no significant effects on nature conservation interests in the study area are predicted, including cumulative effects.
Commercial fisheries
6.39 The commercial fisheries assessment is based on detailed study of the current areas fished and the fishing fleet working in the area, with full details on the baseline available in Volume 4; Annex 8-1, and the EIA presented in Volume 2; Chapter 8 of the ES.
Considerable consultation has been undertaken (and is still ongoing) with regulators and the fishing community.
6.40 A number of measures are included in the proposals as embedded mitigation against potential impacts to commercial fisheries. These include agreed ways in which the community will continue to be consulted and communicated with prior to, and throughout, the construction phase, for example via the appointment of a Fisheries Liaison Officer and Marine Traffic Co-ordinator, together with provision of adequate warning of works, reporting of potential snagging risks, sufficient cable burial or cable protection and the use of guard vessels.
6.41 The potential impacts identified for assessment from consultation completed to date are primarily connected to the construction phase. These include the temporary displacement of fishing vessels around areas of work, a disruption to or loss of fishing activity, an increase in travel time for fishing vessels displaced and an increased pressure on existing fishing grounds if fishing vessels become more concentrated elsewhere. Impacts from decommissioning were identified to be comparable to, or lesser than, those predicted for the construction works.
27
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
6.42 During operation, the potential for impact relates to snag risk for mobile fishing gear and disruption to fishing activity arising from cable maintenance.
6.43 Overall, the impact assessment found that the cable route forms part of a much larger fishing ground and the nature of the construction works for the proposed development means that only part of the cable route would be affected by construction at any given time.
6.44 Taking account of the proposed mitigation and the short duration of construction, the assessment concludes that there are no potentially significant effects likely during construction, operation or decommissioning either for the project alone or cumulatively.
Socio-economics
6.45 The assessment of socio-economic effects is presented in the onshore section as the assessment has been undertaken on a combined, project-wide basis (see Section 7 below).
Marine Historic Environment
6.46 The assessment of marine and coastal archaeology draws on a desk-based archaeological study of the offshore cable corridor together with a review of site-
specific survey data collected. The information on the baseline for that assessment is available in full in Volume 4, Annex 11-1, with the EIA presented in Volume 2, Chapter 11 of the ES. The study identified a number of wreck sites, together with features of potential archaeological interest. Those features taken forward for EIA include submerged landscapes, known as wreck sites, possible wrecks, buried wrecks and various objects, debris and features that were revealed by surveys.
6.47 Impacts assessed were based on the potential for physical loss of archaeological features, for example within the ‘footprint’ of the cables but also as a result of the use of vessels that make contact with the seabed to hold station (for example those that use legs or anchors).
6.48 The assessment takes account of the embedded mitigation measures proposed, which include ongoing consultation with regulators, careful routing of the cable and the inclusion of appropriate methods to deal with any previously unknown features which are found during construction. In all cases, the potential for impact is described in the ES as being minor at most (including both adverse and beneficial effects) and is therefore not considered significant.
28
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
6.49 Consideration has also been given to the impact of the proposal upon the historic seascape character of the area. This draws upon a characterisation study of the marine area extending from Withernsea in East Yorkshire to Newport in Norfolk which was completed by the Department of Archaeology in the School of History, Classics and Archaeology at Newcastle University for English Heritage. Historic seascape character is defined by the way that marine areas have been utilised, altered and affected by human activities and particularly how the character of those areas is perceived as a result of human activity and cultural and historic associations.
6.50 The assessment considers how the installation and operation of the proposed cables may change the character of the area. Due to the limited extent of the potential impact and the established presence of infrastructure associated with the energy industry in the area all potential effects, including cumulative effects, are considered to be negligible and therefore not significant.
Shipping and navigation
6.51 The assessment of shipping and navigation considers a study area in the vicinity of the Triton Knoll Electrical System and the TKOWF. Consultation has been
undertaken, which has provided information on the baseline environment but also on the types of impact that require assessment.
6.52 Consultees have included those bodies with statutory, commercial and/or recreational interests. As agreed during consultation, the Shipping and Navigation Chapter of the ES (Volume 2, Chapter 9) draws on the Marine Navigation Risk Assessment undertaken for the TKOWF, together with resources such as the Royal Yachting Association Atlas for information on recreational use of the area and information on aspects such as the routes travelled by marine aggregate dredgers. The main commercial shipping routes in the vicinity are shown in Figure 6-4.
6.53 The assessment of shipping and navigation takes account of the change in shipping anticipated as part of the project, the current water depths in the area, together with vessel draft and potential for cable installation to affect the existing water depth.
6.54 The project has included a number of embedded mitigation measures, such as appropriately manned vessels, communication of information to other sea users, provision of guard vessels and so on, in line with guidance from the Maritime and Coastguard Agency, which follow standard, accepted industry best practice.
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© Crown copyright, All rights reserved. 2014 License No. EK001-20140601. Contains Ordnance Survey data © Crown copyright and database right 2014. Not to be used for navigation.
Figure 6-4The main shipping routes within and in the
vicinity of the Triton Knoll Electrical System
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
6.55 The EIA considers how the construction, operation and decommissioning of the Triton Knoll Electrical System project may have the potential to reduce the available space for vessels to navigate through the area, any restrictions on the ability to anchor, the potential for interaction with vessels crossing the area (for example fishing vessels or aggregate dredgers) and a reduction in water depth where cable protection is required or existing pipelines are crossed.
6.56 In particular, the concerns assessed include the potential for collision, the risk of grounding and the need for other vessels to alter their course, potentially increasing their journey time. The EIA concluded that all potential impacts, both for the project alone and cumulatively with other projects, were tolerable or of negligible significance and are therefore not considered significant.
Other marine users
6.57 The consideration of ‘Other Marine Users’ covers a broad range of interests, with those considered relevant to the Triton Knoll Electrical System agreed during scoping consultation and considered within the ES, within Volume 2, Chapter 10. These are as follows:
• Telecommunications, power cables and pipelines, collectively termed ‘linear infrastructure‘;
• Marine aggregate extraction; and
• Sea defences.
6.58 The assessment uses information received during consultation together with information received directly from the UK Hydrographic Office, The Crown Estate, telecommunication operators and existing recent regional and national scale studies. Figure 6-5 summarises the presence of other marine users in the vicinity of the Triton Knoll Electrical System.
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© Crown copyright, All rights reserved. 2014 License No. EK001-20140601. Contains Ordnance Survey data © Crown copyright and database right 2014. Not to be used for navigation.
Figure 6-5Other Marine Users
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-13.5 - -8.3
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-45.2 - -31.5
-62.1 - -45.3
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
6.59 The EIA considers aspects such as the potential for direct damage to occur to existing infrastructure, the exclusion of other activities from the area and the effect on sea defences.
6.60 The project includes a number of embedded mitigation measures, in line with standard and accepted industry best practice, such as issuing relevant information to other marine users, consultation and agreement on how existing cables or pipelines should be crossed, use of guard vessels during works and the selection of construction methods to minimise potential impact on coastal defences.
6.61 As a result of the embedded mitigation measures included, the assessment concludes that the impacts of the proposed development, alone and cumulatively with other projects, were negligible and therefore no significant effects were considered likely to occur.
7 ONSHORE EFFECTS
Landscape and Visual
7.1 A Landscape and Visual Impact Assessment (LVIA) has been undertaken as part of the onshore works, which has taken account of the IEC, Substation, existing National Grid substation and the works at the landfall and along the onshore cable route. The assessment has considered the potential for visual effects and impacts to the landscape and visual receptors to occur across the area from the landfall point to the existing National Grid substation at Bicker Fen. The assessment is presented within Volume 3, Chapter 2 of the ES. The assessment included both desk and site based study, modelling and the production of photographic representations (photomontages) of the infrastructure.
7.2 During the scoping consultation and as a result of the EIA process, a number of measures have been included as part of the project that offer embedded mitigation for potential visual and landscape impacts. These have included careful choice of the cable route taken by the project, the construction methods to be used, selection of the locations for permanent, above-ground infrastructure (substation and IEC), the design
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
of permanent structures, as well as commitments to site restoration, planting and landscaping post-construction. Figure 7-1 shows the proposed outline landscape mitigation strategy around the IEC, with that for the Substation shown on Figure 7.2.
7.3 The main sources of potential impact on the landscape and visual environment during construction are associated with the presence of construction equipment and the temporary construction facilities. Impacts during the operational stage will arise from the presence of the permanent infrastructure which will be in place for the lifetime of the project. No potential for significant effects were considered to arise from decommissioning.
7.4 The assessment also identified the features that may be sensitive to such change, such as existing landscapes and specific viewpoints, including views from residential properties.
7.5 A significant effect has been identified on a single landscape unit during construction along the cable route unit, however this will cease once construction has completed. Significant effects on visual receptors have also been predicted during construction and operation of the IEC (from two viewpoints which are residential properties) and at the substation (for three
viewpoints during construction and once the substation is operational). Significant effects from the construction phase will cease once construction is completed. However, significant effects remain for these viewpoints during operation until the landscape planting that screens the two permanent sites has had time to grow. Once the planting has established, any residual visual effects are considered to be not significant and no cumulative effects are predicted.
7.6 The assessment also considered potential effects for works at the existing National Grid substation at Bicker Fen, however all effects were found to be limited in extent across the life time of the project and none were found to be significant.
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© Crown copyright, All rights reserved. 2015 License number 0100031673. Contains Ordnance Survey data © Crown copyright and database right 2015
Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, i-cubed, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community
Triton Knoll Electrical System
Figure :Intermediate Electrical CompoundLandscape and VisualMitigation Strategy
SCALE: @ A3
Source: Global Land Cover Facility, www.landcover.org.
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Coordinate System: British National Grid
Projection: Transverse MercatorDatum: OSGB 1936
Units: Meter
Proposed mixedwoodland planting
Proposed lower levelwoodland edge planting
10m clearance from fence line- includes a 6m grass strip and4m woodland edge planting
2m grass strip and 4m low level woodland edge/hedgerowspecies at the site frontage
12m
30m
23m
82m
Intermediate ElectricalCompound, Accommodating
all the Above-Ground Electrical Infrastructure
(AGEI)GRAINSTORE
SKEGNESSSTADIUM
Location of Temporary ConstructionCompound - restored to agriculturefollowing completion of construction
MARSH LANE
Access Road - includes a2m grass strip either side
38m
A maximum 72m wide gap in tree planting isrequired along this boundary for cable entryand exit to the compound with the exact locationto be determined post-consent. This will avoidtree root damage to underground cables.However, shallow rooting woodland edgespecies are permitted within the corridor
A maximum 72m wide gap in tree planting isrequired along this boundary for cable entryand exit to the compound with the exact locationto be determined post-consent. This will avoidtree root damage to underground cables.However, shallow rooting woodland edgespecies are permitted within the corridor
9 m clearance between planting and the Orby South Drain Branch No 2
552000 552200 552400 55260036
74
00
36
76
00
36
78
00
36
80
00
Legend:
Proposed Development Boundary
Total area of land required for theIntermediate Electrical Compound,
Permanent and Temporary AccessTracks, Underground Cabling andDrainage and Landscape Mitigation
Intermediate Electrical Compound,
accommodating all the above groundelectrical infrastructure (AGEI)
Temporary Construction Compound(TCC)
Defined Permanent Access Road
Proposed Amenity Grass
Proposed Woodland Edge Planting
Proposed Woodland/Tree Planting
Orby South Drain Branch No 2
1:2,500
0 50 100
Metres /
Notes:-
This map contains data from the following sources-Bing Maps (January 2014)
Lincolnshire County Council Council (June 2014)
00
Chk App
03/03/2015 First Draft NH JM HT
Rev Date Description Drn
01 03/03/2015 Revised PDB DR AJ JM
© Crown copyright, All rights reserved. 2015 License number 0100031673. Contains Ordnance Survey data © Crown copyright and database right 2015
Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, i-cubed, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community
Triton Knoll Electrical System
Figure :Substation Landscape and
Visual Mitigation Strategy
SCALE: @ A3
Source: Global Land Cover Facility, www.landcover.org.
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Coordinate System: British National Grid
Projection: Transverse MercatorDatum: OSGB 1936
Units: Meter
Notes:-
This map contains data from the following sources-Bing Maps (January 2014)
Lincolnshire County Council Council (June 2014)
00
Chk App
03/03/2015 First Draft NH JM HT
Rev Date Description Drn
Substation, Accommodatingall the Above-Ground
Electrical Infrastructure(AGEI)
Location of Temporary ConstructionCompound - restored to agriculturefollowing completion of construction
SO
UTH
FO
RTY
FO
OT D
RA
IN
Access Road - includes a2m grass strip either side
Proposed mixedwoodland planting
Proposed lower levelwoodland edge planting
51m
48m
71m
71m
22m
10 m clearance from fence line– includes a 6 m grass strip and4 m woodland edge planting
71m
A maximum 72m wide gap in tree planting isrequired along this boundary for cable entryand exit to the compound with the exact locationto be determined post-consent. This will avoidtree root damage to underground cables.However, shallow rooting woodland edge speciesare permitted within the corridor
A maximum 72m wide gap in treeplanting is required along thisboundary for cable entry and exitto the compound with the exactlocation to be determined post-consent.This will avoid tree root damage tounderground cables. However, shallowrooting woodland edge speciesare permitted within the corridor
518500 519000 519500 52000033
95
00
34
00
00
34
05
00
1:5,000
0 100 200
Metres /
Legend:
Proposed Development Boundary
Total area of land required for theSubstation Compound, UndergroundCabling, Permanent and Temporary
Access Tracks and Drainage andLandscape Mitigation
Substation compound, accommodatingall the above-ground electricalinfrastructure (AGEI)
Temporary Construction Compound(TCC)
Permanent Access Track
Temporary Construction Access
Defined Permanent Access Road
Proposed Amenity Grass
Proposed Woodland Edge Planting
Proposed Woodland/Tree Planting
Wind Turbine Buffer. Area adjacent toturbine - max 5m height planting
01 03/03/2015 Revised PDB DR AJ JM
Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Socio-economic assessment
7.7 Socio-economics considers a large number of aspects, including employment and economics, demographics, education and skills, quality of life, risk to health and safety, access, and recreation and tourism. As such, both the baseline description and the EIA draw on numerous chapters within the overall ES, with the full baseline description presented in Volume 5; Annexes 3-1 (Socio-economic study area), 3-2 (recreational angling) and 3-3 (employment and economic impact). The assessment is presented in Volume 3, Chapter 3.
7.8 Given the broad spread of topics included within socio-economics, the sources of information to describe the baseline were extensive, with the assessment drawing on a desk based study of publicly available data.
7.9 During consultation, a number of potential impacts were found to be not significant, with agreement reached that these could be scoped out of further assessment. These include operational impacts offshore, a number of operational impacts onshore and at the landfall and all potential impacts during decommissioning.
7.10 The project design incorporates a number of measures to mitigate the potential for impact, including the
avoidance (where feasible) of existing buildings, areas under active use and PRoW, appropriate choice of construction methods, the use of best practice and ongoing provision of information on both the proposed works (including PRoW closures/diversions) and also on the availability of tendering opportunities for local businesses.
7.11 The assessment has considered the potential for impact, including cumulative effects, finding that for the majority these will be of negligible significance, with some being of minor significance, including the potential for some positive impacts.
Terrestrial Ecology
7.12 The assessment of terrestrial ecology draws on a range of site-specific ecology surveys and existing information for the area. During scoping, extensive consultation was undertaken, which has refined the focus of the terrestrial ecology assessment, which considers the potential for impact to animal species and the temporary or permanent loss of a range of habitats during the development and operation of the project. The EIA is presented in Volume 3, Chapter 4 of the ES.
7.13 The consultation discussions, along with the assessment process itself, have identified a number of
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
mitigation measures that have been adopted for the project. In particular, these include measures to avoid sensitive habitats or species through careful routing of the cable, consideration of the techniques used during construction and the development of an ecological and landscape mitigation strategy.
Figure 7-3 Example of a cable corridor during
restoration
7.14 The main potential for impact to terrestrial ecology will be linked to periods of construction, although operation and decommissioning effects were also assessed. Construction effects include, for example, the direct removal of small areas of habitat to enable the components of the project to be installed; periods of
disturbance (both related to noise and visual impacts); and impacts from the crossing of water courses where there may be temporary changes to flows.
7.15 Following agreement on the issues to be addressed in the ES during consultation, the following habitats and species are assessed in the ES:
• A small proportion of the Huttoft Bank Dunes Local Wildlife Site, which is valued locally for nature conservation, will be crossed by the works. Potential for impact includes clearance of vegetation and excavation, with these impacts being temporary and followed by restoration on completion of the construction works. No significant effects are predicted.
• The removal of hedgerows along the cable route will affect these habitat features. However, the lengths of hedgerows removed will be replaced, restored and where possible improved once construction has completed and mitigation during the construction works will ensure that no significant effects will occur.
• Existing and proposed fields for the Lincolnshire Coastal Grazing Marsh are being crossed by the cable route. However, a range of mitigation options have been designed to make sure that,
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
together with the small proportion of the habitat potentially affected, direct impacts to the area will be minimised. The assessment concludes a negligible level of effect, which is not significant.
• A number of species of interest are found in the area, including badgers, water vole, bats, birds and reptiles. These species have been identified during site-specific surveys, with a range of mitigation measures included in the project design and construction methods aimed at reducing the potential for impact. As a result, no significant effects are predicted either for the project alone or cumulatively.
Land use, agriculture and soils
7.16 This chapter of the ES focuses on agricultural land use together with open access land, common land and utilities, with the EIA presented in Volume 3, Chapter 5. The study draws on a number of existing and standard references, which together describe existing land type and land use including the quality of that land. The land is principally agricultural, crossed by existing utilities (including electricity, gas and water).
7.17 In response to consultation, and in line with standard best practice, a number of mitigation measures are
included in the project design and construction methodology. These include careful consideration of the route chosen and the location of temporary and permanent structures, liaison with farmers and landowners to manage access during construction, implementation of a Soil Management Plan (SMP) (an Outline SMP can be found at Application Document 8.7.5), adherence to best practice including regarding notifiable disease or invasive species and the inclusion of measures for reinstatement of land.
7.18 The EIA considers a wide range of potential impacts, including temporary disruption to existing land use, soil disturbance, spread of disease or invasive species, a permanent change or restriction on land use and the effect of heat from buried cables. With the exception of potential effects on marginal agricultural land holdings, no significant effects were predicted. For marginal agricultural land holdings, a potential significant effect was identified for smaller farms as these were considered to be more sensitive to disruption than larger holdings. These effects would be temporary and the mitigation measures adopted would reduce disruption as far as possible. Following restoration of farmland after construction, no permanent significant effects are predicted to arise from the project alone or cumulatively.
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
Geology, hydrogeology and ground conditions
7.19 The description of geology, hydrogeology and ground conditions considers the geology, the groundwater (water underground) and ground contamination (e.g. pollution in the soil). The existing conditions have been described on the basis of publicly available data combined with site surveys, with the EIA presented in Volume 3, Chapter 6. During the project consultation, agreement was reached that no significant effects are likely during operation and decommissioning, with these aspects therefore scoped out of the assessment. An example of the width of the Study Area investigated is given in Figure 7-4.
Figure 7-4 Example of study area and Proposed
Development Boundary
7.20 The project includes a number of mitigation measures, which will be detailed in a Code of Construction Practice (CoCP) and Site Waste Management Plan (SWMP). An Outline CoCP and an Outline SWMP can be found at Application Documents 8.7 and 8.7.7 respectively. Key to the mitigation measures are the avoidance of areas sensitive to such development and use of appropriate construction methods (including choice of equipment, burial of cables), together with
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
ongoing consultation and compliance with the relevant legislation, best practice and guidance.
7.21 The CoCP and SWMP will include measures to manage construction processes appropriately and to control waste.
7.22 The EIA considers a range of aspects related to the construction phase. These include: unforeseen contamination; contamination of the air, ground or groundwater; drainage; designated geological sites; sterilisation of mineral resources; and the accidental spread of contaminated material. The potential for impact to all these features is considered to be minor at most and are therefore not considered to be significant.
7.23 The EIA also concluded the potential for cumulative effects was not significant.
Hydrology and flood risk
7.24 The assessment of hydrology and flood risk considers surface water (primarily streams and ditches but this also includes rivers, lakes and ponds) together with the potential for the project to cause a change in the flood risk to the surrounding area. The information is supported by three Annexes; a baseline report, a Water Framework Directive (WFD) Assessment and a Flood
Risk Assessment (FRA) (Annex 7-1, 7-2 and 7-3 respectively.
7.25 The description of the baseline has been informed by site visits, desk study and consultation and draws on a number of datasets, for example reports prepared by the Local Authorities. The EIA is presented in Volume 3, Chapter 7.
7.26 The project includes a number of embedded mitigation measures to reduce or prevent significant effects. These include the selection of the cable route and areas for construction, raising the ground level at the Substation IEC and parts of the National Grid substation sites to protect equipment from potential flooding, use of appropriate methods of construction (including detailed measures near water) and following and applying appropriate industry best practice and guidelines.
7.27 The EIA considered a number of possible impacts arising from construction, operation and/or decommissioning of the proposed development, alone and cumulatively, which include the following:
• Surface water quality and quantity
• Tidal flooding
• Flooding from rivers and streams (fluvial);
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
• Flooding from land (pluvial)
• Groundwater flooding
• Cumulative impacts
7.28 The EIA considers the potential for the project to affect the existing flow rate and direction of water. With the inclusion of the proposed mitigation, notably including drainage plans and avoiding direct impacts to main watercourses using HDD techniques, the potential for impact was found to be negligible and is therefore not considered significant.
Historic environment
7.29 The historic environment assessment takes account of features found above and below the ground, which can range from listed buildings to the remains of human activity (which could include artefacts ranging from worked flints, to pottery fragments or historic structures) or other evidence of historic interest. The understanding of the baseline historic environment for the project draws on site visits together with existing literature and databases, with the EIA presented in Volume 3, Chapter 8 of the ES. An ‘Outline Onshore Historic Environment Written Scheme of Investigation (WSI)’ (Application Document 8.11) has been prepared as part of the application, which details the
commitments and methodologies for further assessment and mitigation, including commitments to further site investigation work before construction starts.
7.30 To protect features of the historic environment, a number of embedded mitigation measures are included which draw strongly on best practice guidance. These include avoidance of sensitive features, reinstatement of features such as hedgerow boundaries and measures to record items found during construction.
7.31 The potential for impact is linked to the construction stage, including aspects such as ground clearance and the groundworks required before construction can start. No potential for impacts during operation was identified and any decommissioning effects were found to be lesser than those assessed for the construction phase.
7.32 The impact assessment considers each identified feature to assess the significance of the potential for impact, finding the potential significance of effect to be negligible at most or, for many, none; and are therefore not considered significant. No significant cumulative effects are predicted.
7.33 It should be noted that further archaeological survey work will be undertaken in accordance with an agreed scheme of investigation, which will include geophysical
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
and metal detector surveys as well as targeted trial trenches. The works will be carried out prior to construction and as part of the proposed mitigation. The aim of the works is to define the size of features, to identify where trial trenches should be dug and to identify areas of soil that have been disturbed previously.
Traffic and access
7.34 The traffic and access assessment includes the description of existing transport in the area and assesses how the traffic, access, the routes taken and the delivery of abnormal loads as part of the Triton Knoll Electrical System project will affect the existing situation. The EIA is presented in Volume 3, Chapter 9 of the ES.
7.35 The potential for impact during operation has been scoped out of assessment as a result of discussions during the consultation process, with the assessment focused on the construction phase. Decommissioning effects were considered to be no worse, and likely lesser, than those arising from the construction phase
7.36 The assessment considers various aspects including where and how access to working areas will be achieved, the use of temporary haul roads, road
crossings and the construction programme. Details such as the type and number of vehicles accessing the site (and the routes they will take), the routes taken by HGVs (including the type of load, size of the vehicle and the number of such vehicles required) and the management of abnormal loads all inform the EIA.
7.37 An increase or change in the traffic using the existing road network has the potential to impact on existing road users. The project design has given careful consideration to the potential for impact, for example through choice of location for works, the timing of works and the routes chosen for HGV and abnormal loads. The Traffic Management Plan, provided as an ‘Outline Traffic Management Plan’ with the application, will formalise the mitigation (Application Document 8.9).
7.38 The potential for impact from the project alone and cumulatively with other projects has been assessed as negligible when the embedded mitigation is taken into account and is therefore considered not significant.
Air quality
7.39 The EIA for air quality considers the potential impacts on the existing air quality as a result of construction and decommissioning, with the potential for impact during operation scoped out of the assessment during
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
consultation. Information on the existing air quality has been sourced from monitoring locations maintained by the local councils together with data collated by Defra. The EIA is presented in Volume 3, Chapter 10.
7.40 The assessment of potential impacts to air quality has considered the level and type of road traffic predicted and the potential for dust that construction and decommissioning will create. An Outline Traffic Management Plan and an Outline Air Quality Management Plan (Application Document 8.7.4) provided in support of the application provide details of the mitigation measures and working practices that will be followed for the proposed development, in line with best practice.
7.41 The ES concludes that with the proposed mitigation in place, the works associated with the construction and decommissioning of the Triton Knoll Electrical System works will not cause a significant effect on local air quality either alone or cumulatively with other projects.
Noise and vibration
7.42 The assessment of noise and vibration focuses on the potential for impact on people – the potential for impact on ecology is discussed separately. The existing conditions along the cable corridor were informed by
noise measurements undertaken in consultation with local authorities, with the EIA presented in Volume 3, Chapter 11.
7.43 There is considerable guidance available regarding noise and vibration, not only how to assess the potential for impact but also how to mitigate against that impact. The assessment follows these best practice guidelines and the project design reflects this and includes embedded mitigation. For example, careful routing to avoid areas of sensitivity, limiting construction work primarily to daylight hours, with night time work only where necessary for technical reasons, use of the appropriate types of equipment and implementation of a Code of Construction Practice (CoCP).
7.44 For particular activities, temporary noise barriers will be installed with ongoing communication of the progress and nature of the works to residents.
7.45 The potential for impact is assessed in the ES to be primarily minor. However, there may be occasions when trenchless excavation works, for example using HDD, need to continue during the night time. If this occurs in locations close to houses, this has the potential to lead to a moderate level of impact for the short period of time the works take place. This effect is
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
considered to be significant. Further management would be applied in these circumstances to reduce the likelihood of a significant effect actually occurring. No significant cumulative effects are predicted.
8 POTENTIAL FOR INTER-RELATED EFFECTS
8.1 Inter-related impacts are those that may arise through the interaction of individual impacts on a single receptor. Whilst the EIA has identified that scope exists for inter-related impacts between a number of topics, inter-related effects will not be any more significant than the individual impact effects.
9 POTENTIAL FOR CUMULATIVE EFFECTS
9.1 The potential cumulative impacts from the Triton Knoll Electrical System together with other wind farms and development existing or planned in the vicinity has been assessed in the ES. In all cases, cumulative effects were considered to be no greater than those arising from the proposed development alone, with no significant cumulative effects identified.
10 POTENTIAL FOR TRANSBOUNDARY EFFECTS
10.1 Transboundary effects is a term used to describe the effects of a development on other countries. Following completion of a transboundary screening matrix (Planning Inspectorate reference EN020019) and in agreement with The Planning Inspectorate, it is considered that transboundary impacts are not likely to arise as a result of this development. Transboundary effects have therefore not been considered further in this ES.
11 CONCLUSIONS
11.1 This NTS provides a summary of information presented in the ES and is published as part of the application for a Development Consent Order for the construction and operation of the Triton Knoll Electrical System.
11.2 The Triton Knoll Electrical System is required to link the consented TKOWF to the national grid. When built, the TKOWF will have a capacity of up to 900MW. It will provide a notable contribution to the UK’s renewable energy targets. The detail of the Triton Knoll Electrical System has been developed over many years of assessment and the proposed development takes
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Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement Non-Technical Summary
account of environmental, human, engineering, operational and commercial factors.
11.3 Development of the Triton Knoll Electrical System will also result in creation of jobs during the construction and operation stages. This is estimated in the PEI as equating to around 500 full time equivalent jobs per year nationally over the construction phase. Of these, approximately 300 will fall within the East Midlands and some 50 full time equivalent jobs per year will be supported in Lincolnshire.
11.4 The potential impacts of the proposed Triton Knoll Electrical System on the environment have been subject to detailed and thorough assessment in accordance with relevant regulations and guidance. As part of this EIA process, consultation has been carried out with a wide range of stakeholders and this has been used to amend and improve both the assessment and the project, where appropriate and feasible.
11.5 The assessment has concluded that the majority of impacts are not significant and that where potentially significant effects have been identified, appropriate mitigation has been set out that will act to reduce or avoid those effects to an acceptable level.
12 FURTHER INFORMATION
12.1 More detailed information on the Triton Knoll Electrical System is included in the full ES document of which this NTS is a summary. The ES documents and supporting information can be downloaded from the Planning Inspectorate website at the following address:
http://infrastructure.planningportal.gov.uk/projects/east-midlands/triton-knoll-electrical-system/
12.2 Copies of the ES on CD can be requested:
• By post:
FREEPOST
RTBK-ABSH-TGLU
Triton Knoll Offshore Wind Farm Ltd
RWE Innogy UK
Trigonos
Windmill Hill Business Park
Whitehill Way
Swindon
SN5 6PB
12.3 A charge will be made for paper copies.
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