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Record of Appropriate Assessment – East Anglia ONE Offshore Windfarm

Regulation 63 of the Conservation of Habitats and Species Regulations 2017, and

Regulation 28 of the Conservation of Offshore Marine Habitats and Species Regulations 2017 (The “Habitats Regulations”)

17 January 2018

Contents

Introduction __________________________________________________________ 2

East Anglia ONE ____________________________________________________ 2

Southern North Sea cSAC _____________________________________________ 2

Requirement 36 _____________________________________________________ 3

Project Details ________________________________________________________ 3

Assesment ___________________________________________________________ 8

Likely Significant Effects ______________________________________________ 8

2016 Appropriate Assessment __________________________________________ 8

Conservation Objectives ______________________________________________ 9

Method ____________________________________________________________ 10

In-combination impacts of other known or potential activities __________________ 16

Proposed Mitigation __________________________________________________ 23

Monitoring _________________________________________________________ 23

Conclusion _________________________________________________________ 24

Appendix 1 – Record of comments received during consultation period ____________ 26

Introduction

East Anglia ONE

East Anglia One Limited (EAOL) was granted a Development Consent Order (DCO) for the

East Anglia ONE Offshore Windfarm (East Anglia ONE) in June 2014. The DCO granted

consent for the development of an offshore windfarm with a capacity of up to 1,200 Megawatt

(MW), located 43km off the coast of Suffolk, and authorised the development of up to 240 wind

turbines and associated offshore and onshore infrastructure.

EAOL subsequently applied for a non-material change to the DCO, in order to include a further

option which would allow for the use of a High Voltage Alternating Current (HVAC)

transmission system. The Secretary of State (SoS) confirmed the decision to make the non-

material changes to the DCO and published the East Anglia ONE Offshore Wind Farm

(Corrections and Amendments) Order 2016 on the 24th March 2016.

On 16th September 2016, EAOL wrote to the SoS, the MMO and relevant authorities to

provide notification that the HVAC technology had been selected.

The HVAC option for East Anglia ONE allows for a gross electrical output capacity of 750MW

comprising up to 150 wind turbines. However, the final project design envelope for East Anglia

ONE, which has now secured a Contract for Difference, is to construct a 714MW 102 wind

turbine project. This Record of Appropriate Assessment, which relates to the Marine Mammal

Mitigation Protocol (MMMP) necessary to discharge Requirement 36 of the DCO, will assess

the planned offshore design of East Anglia ONE comprising 714MW and 102 wind turbine

generators. This is on the basis that the MMMP contains a commitment not to exceed this final

project design envelope which is set out in the MMMP and summarised in Table 11. Any

increase in the total capacity of the project or number of wind turbine generators from those set

out in Table 1 would therefore require a variation to the MMMP to be approved by the

Secretary of State which would be subject to an additional Habitats Regulation Assessment.

Southern North Sea cSAC

A formal consultation was instigated by the Joint Nature Conservation Committee (JNCC) on

19th January 2016, closing on 3rd May 2016, on a suite of possible Special Areas of

Conservation (pSACs) within UK waters being brought forward under the Habitats Directive, for

which harbour porpoise was the sole feature of interest. Following the consultation process,

1 Scottish Power Renewables, November 2017. Table 1, Page 6; Summary of MMMP Mitigation Measures.

Document submitted to fulfil Requirement 36 of The East Anglia ONE Offshore Wind Farm (Corrections and Amendments Order) 2016

3

the JNCC and the Statutory Nature Conservation Bodies assimilated the responses received

and issued a consultation report to Government on 28th September 2016.

Clearance was given to the sites, which were subsequently submitted to the European

Commission for approval to designate on 30th January 2017 – at which point, the sites

became candidate SACs (cSACs).

Seasonal differences in the relative use of the site have been identified based on the analyses

of Heinänen and Skov (2015)2 which shows that harbour porpoise occur in elevated densities

in some parts of the site compared to others during summer and winter. JNCC and NE’s Draft

Conservation Objectives and Advice on Activities document (JNCC & NE, 2016)3 states that

seasonality in porpoise distribution should be considered in the assessment of impacts and

proposed management.

East Anglia ONE offshore wind farm is located wholly in the winter extent of the cSAC.

Requirement 36

As part of the non-material change application, a Habitats Regulation Assessment (HRA) was

undertaken to assess any potential impacts of the change application on the pSAC.

The HRA considered the potential for; injury, noise disturbance and displacement as a result of

piling activity and vessel movements during construction; the potential for collisions with

construction and maintenance vessels; potential changes to feeding habitats and prey

distribution during construction and operation; and, the potential in-combination noise

disturbance and displacement impacts from other nearby offshore wind farms, dredging

activities and seismic surveys.

EAOL proposed the use of embedded mitigation measures in relation to the project to offset

the greatest impact to harbour porpoise, which was underwater noise impacts from piling of

foundation structures, causing potential injury and displacement. These were:

To only use pin piles (apart from one monopile for the met mast), which will reduce the

peak noise levels and the area over which noise levels would be experienced, and

2 Heinänen, S. & Skov, H 2015. The identification of discrete and persistent areas of relatively high harbour

porpoise density in the wider UK marine area, JNCC Report No.544 JNCC, Peterborough. 3 JNCC and Natural England, January 2016. Harbour Porpoise (Phocoena phocoena) possible Special Area of

Conservation: Southern North Sea Draft Conservation Objectives and Advice on Activities

4

To use soft start procedures as per JNCC guidance on minimising the risk of

disturbance and injury to marine mammals from piling noise (JNCC, 2010)4.

However, the Secretary of State proposed that additional mitigation was secured through the

development of a Marine Mammal Mitigation Protocol (MMMP) which would be agreed with

DECC (now BEIS), in consultation with the MMO and Natural England, whose purpose would

be to minimise the risk of injury or disturbance to marine mammals during piling operations

and to ensure that the level of underwater noise, in-combination with other plans or projects,

will not have an adverse effect on the integrity of the pSAC. This was secured through

requirement 36 of the varied DCO.

When discharging this requirement the Secretary of State will need to be satisfied that the

MMMP is adequate to prevent East Anglia ONE from giving rise to an adverse impact on the

harbour porpoise feature of the Southern North Sea cSAC in accordance with the Habitats

Regulations.

Requirement 36 of the DCO is as follows:

1) No part of Works No. 1 to 3A must commence until a marine mammal mitigation protocol

with appropriate monitoring surveys, the intention of which is to prevent, amongst other

things—

(a) injury to marine mammals, primarily auditory injury in the vicinity of any piling;

(b) disturbance to marine mammals;

(c) adversely affecting the integrity, within the meaning of the Offshore Marine Conservation

(Natural Habitats, &c.) Regulations 2007(a), of a European offshore marine site or a European

site (defined in regulations 15 and 24 of those Regulations respectively), to the extent that

marine mammals are a protected feature of that site, has been submitted to and approved in

writing by the Secretary of State, after consultation with the MMO and Natural England.

(2) The reference to “marine mammals” means the marine mammals listed as European

Protected Species in Schedule 1 to the Offshore Marine Conservation (Natural Habitats, &c.)

Regulations 2007, and “disturbance” has the same meaning as in regulation 39(1)(b) of those

Regulations.

(3) The undertaker must implement the marine management mitigation protocol agreed under

paragraph (1).”

A suite of documents comprising the MMMP, was submitted to the Secretary of State on 30th

August 2017. This was supplemented by a further document entitled ‘Summary of Mitigation

4 JNCC, August 2010. Statutory nature conservation agency protocol for minimising the risk of injury to marine

mammals from piling noise.

5

Measures’ which was submitted to the Secretary of State on 1 December 2017. The Summary

of Mitigation Measures, which also forms part of the MMMP, sets out a summary of the

mitigation commitments which will be implemented under Requirement 36(3). The Secretary

of State has reviewed the MMMP and records his assessment for the purposes of

Requirement 36 below.

6

Project Details

Table 1: Plan or project details

Type of Plan or

Project

The East Anglia ONE DCO (as varied via a non-material change)

grants development consent for Scottish Power Renewables to

construct, up to a 750 Megawatt (MW) offshore wind farm project

that will be located 43km off the Suffolk coast. Following the award

of a CfD, the offshore design of East Anglia ONE will consist of the

following main components:

Up to 102 Wind Turbine Generators (WTG) to provide an

installed capacity of 714 MW

HVAC transmission system using two export cables

WTG’s installed using only jacket foundations

Up to 2.5 m diameter pin piles for the WTG jacket foundations

1 offshore substation (OSS) constructed on four jacket

foundations.

The whole of the the East Anglia ONE array boundary and the

majority of the offshore cable corridor falls within the Winter Area of

the SNS cSAC. The array area of 200.01km2 represents

approximately 0.5% of the SNS cSAC extent.

Table 2: Details of European sites

Name and Legal Status of

Sites:

Name of Sites Legal Status

Southern North Sea (SNS) Candidate Special Area of

Conservation

7

Figure 1: East Anglia ONE project location and map of SNS cSAC summer and winter

areas

Table 3: Features list

Features Details of pressure Is the feature impacted

by the pressure

Southern North Sea (SNS) cSAC

(Phocoena phocoena);

Harbour Porpoise

Construction of Offshore

Windfarm (OWF)

Yes

8

Assesment

Likely Significant Effects

The 2016 non-material change HRA5 considered impacts of the project on the Southern North

Sea pSAC. As part of the assessment, a likely significant effects (LSE) test was performed to

consider if East Anglia ONE would have LSE on a European site.

The Secretary of State considered the potential impacts of the project both alone and in

combination with other plans and projects on each of the interest features of the; Southern

North Sea pSAC, Hamford Water pSPA and the Outer Thames Estuary pSPA, to determine

whether or not there would be LSE.

The Secretary of State concluded that there would be no LSE on either the Hamford Water

pSPA and the Outer Thames Estuary pSPA. There was however, considered to be LSE on the

Southern North Sea pSAC from anthropenenic noise caused by pile driving and death and

injury by collision from shipping.

2016 Appropriate Assessment

Following the LSE test, an appropriate assessment was performed on the impacts of both

anthropogenic noise caused by pile driving and death and injury by collision from shipping on

harbour porpoise as a feature of the Southern North Sea pSAC.

Following the appropriate assessment, the Secretary of State concluded no adverse effect on

integrity of the Southern North Sea pSAC as a result of death and injury of harbour propoise

from shipping.

The Secretary of State also concluded that the JNCC guidelines for minimising disturbance to

marine mammals did not include provisions to ensure that there would be no adverse effect on

the integrity of the Southern North Sea pSAC from East Anglia ONE in combination with other

plans and projects, and therefore requirement 36 should be added to the varied DCO to ensure

that there is no adverse effect on the integrity of the pSAC.

As requirement 36 was added to the DCO to ensure no adverse effect on the integrity of the

pSAC (now cSAC) from anthropogenic noise from pile driving, the following appropriate

5 DECC, March 2016. Record of The Habitats Regulations Assessment Undertaken Under Regulation 61 of the

Conservation Of Habitats and Species Regulations 2010 and Regulation 25 of the Offshore Habitats Regulations for an Application Under The Planning Act 2008. Project Title: East Anglia One Offshore Wind Farm – Non Material Change

9

assessment is limited to considering this pressure on the cSAC. Table 4 shows the pressures

and features which will be considered in the appropriate assessment.

Table 4: Pressure/feature interactions to be assessed

Pressure Feature

(Phocoena phocoena); Harbour porpoise

Anthropogenic underwater sound (summer

months: 1st April – 30th September inclusive)

Sensitive

Anthropogenic underwater sound (winter

months: 1st October – 31st March inclusive)

Sensitive

Conservation Objectives

In January 2016 Natural England and JNCC released draft conservation objectives and advice

on activities for the cSAC6. The Conservation Objectives for the site are:

To avoid deterioration of the habitats of the harbour porpoise or significant disturbance

to the harbour porpoise, thus ensuring that the integrity of the site is maintained and

the site makes an appropriate contribution to maintaining Favourable Conservation

Status (FCS) for the UK harbour porpoise.

To ensure for harbour porpoise that, subject to natural change, the following attributes are

maintained or restored in the long term:

1. The species is a viable component of the site.

2. There is no significant disturbance of the species.

3. The supporting habitats and processes relevant to harbour porpoises and their prey are

maintained.

The following appropriate assessment will focus on points 1 and 2 (above). It is considered that

point 3 pertaining to supporting habitats and processes relevant to harbour porpoises and their

prey was sufficiently assessed in the March 2016 DECC HRA for the East Anglia ONE non-

material change application.

6 JNCC and Natural England, January 2016. Harbour Porpoise (Phocoena phocoena) possible Special Area of

Conservation: Southern North Sea Draft Conservation Objectives and Advice on Activities

10

Method

The appropriate assessment is based on the Report to Inform the Appropriate Assessment

(RIAA) which was submitted by EAOL as part of the suite of documents comprising the MMMP

submitted to the Secretary of State in August 2017.

The methodology in the RIAA is based on advice from the SNCBs to EAOL on what constitutes

an adverse effect on the integrity of the cSAC. The SNCB advice was to use a generic

effective disturbance range (EDR) of 26km around piling events and UXO clearance to

calculate the daily and seasonal spatio-temperal effects on the cSAC. The thresholds

recommended by the SNCBs which would constitute an adverse effect on the integrity of the

cSAC was no more than 20% of the site being disturbed over a 24 hour period and no more

than 10% of the site being disturbed across as season (i.e. the summer and winter seasons).

These thresholds apply to the seasonal extents of the cSAC, i.e. disturbance from pile driving

in summer would only affect the summer extent of the cSAC.

Table 5: Appropriate Assessment of effects of East Anglia ONE project alone on the Southern North Sea cSAC

Pressure Interest

Feature

Favourable condition target for relevant attribute (including range of natural variation) based on conservation objectives

Contribution of management or other unauthorised sources to attribute and /or feature condition

Adverse effect of proposal alone on attribute and/or feature

Adverse effect of proposal in combination with other plans or projects, on attribute and /or feature

Can adverse affects be avoided?

Adverse affect on integrity (long term or short term) (yes, no or uncertain)?

Anthropogenic underwater sound from percussive piling

Phocoena phocoena; Harbour Porpoise

Maintain and restore condition

This project is not necessary for the management of the site or feature. There are potential impacts on the feature from the project.

This assessment will consider the impacts of lethal or permanent injury

(permanent Threshold Shift (PTS)), temporary auditory injury (Temporary

Threshold Shift (TTS)) and disturbance of harbour porpoise within the

cSAC.

The southerly part of the cSAC is recognised for its importance for

harbour porpoise during the winter season (01 October – 31 March). The

whole of East Anglia ONE (200.02km2) is located within the southern part

of the cSAC and represents a total of 0.5% of the total cSAC.

The mitigation of permanent and temporary injury to harbour porpoise will

be secured through the Marine Mammal Mitigation Protocol (MMMP)

Procedure7. Measures in the MMMP Procedure include:

Use of marine mammal observers (MMOb) and passive acoustic

No. See in-combination assessment.

No adverse effects identified.

No adverse effect on site integrity.

7 Scottish Power Renewables – Requirement 36 Report, August 2017 EA1-CON-B-GBE-23782; Appendix A:MMMP Procedure

12

monitoring (PAM). There must be a minimum of 30 minutes with

no marine mammals detected before piling can commence.

Use of an Acoustic Deterent Device (ADD) for at least 15 but no

more than 30 minutes before the start of piling.

A soft start of at least 20 minutes to allow marine mammals to

move away from the noise source before noise can reach a level

that could cause injury.

It is noted that the pin piles which will be used in the East Anglia ONE

wind turbines and offshore substation will have maximum hammer

energies of 1800KJ and 2400KJ respectively which would result in a PTS

potential impact range of 272m (wind turbines) and 317m (offshore

substation). However, in line with JNCC guidance, the MMMP Procedure

ensures that a precautionary mitigation zone of 500m from the pile

location is used. EAOL will ensure (through the MMMP Procedure) that

no marine mammals are present in the mitigation zone 30 minutes before

piling commences.

With regard to disturbance impacts, Scottish Power Renewables

commissioned project specific underwater noise modelling which

estimated a distance of 19km from individual pin piling events within

which disturbance or avoidance is anticipated. It is noted that a

precautionary worst case disturbance distance of 26km was also

presented which is in line with Tourgaard et al 2014 and the SNCBs

current advice.

EAOL states that for an EDR of 26 km the maximum spatial disturbance

from a single piling event is approximately 2486km2 for the winter and

660 km2 for the summer components of the cSAC.

Worst case was considered to be two piling events occurring within a 24

hour period at a maximum separation of 8km and a disturbance range of

26km. In the winter months this scenario would result in no foundation

piling producing a spatial effect greater than 20% in a single 24 period. In

the summer months, East Anglia ONE activity will only affect 2% of the

respective area. It is noted that the project specific disturbance distance

13

of 19km reduces disturbance in a 24 period to 11% in winter and 1% in

summer.

Piling activity will be constrained to take place between 10th February

2018 and the 31st October 2018. No more than two wind turbines will be

installed in any one 24 hour period with (excluding installation of the

offshore substation) no concurrent piling. 24 hour working will be

employed to ensure all piling is completed within the dates above. It is

noted that these commitments will ensure that at least 80% of the piling

takes place in the summer months largely avoiding the sensitive winter

period for harbour porpoise.

EAOL state that there will be a worst case of 50 piling days in the 2017/18

winter season, 183 days in the 2018 summer season and a further 31

days in the 2018/19 winter season, produced an average cSAC effect (as

spatial overlap) of 4% in winter 2017/18, 1% in summer 2018 and 3% in

winter 2018/19. All these seasonal average extents are well under the

recommended SNCB 10% seasonal threshold.

Based on the information above, the Secretary of State considers that the

construction of East Anglia ONE alone will not result in an adverse effect

on the integrity of the cSAC from anthopogenic underwater sound from

percussive piling.

Anthropogenic underwater sound from unexploded ordinance (UXO) clearance by detonation




The need for UXO clearance detonations has yet to be determined,

however if UXO clearance is necessary then the following will be

undertaken to mitigate injury and disturbance.

It should be noted that UXO clearance is subject to a separate licence

application to the MMO through the Marine and Coastal Access Act 2009

and does not, therefore, come under the remit of Requirement 36. The

Marine Licence application will be made if UXO is found and clearance is

No. See in-combination assessment.



14

deemed necessary. As part of the Marine Licence application, the

impacts of lethal or permanent injury (PTS), temporary auditory injury

(TTS) and disturbance of harbour porpoise from UXO detonation within

the cSAC will be mitigated by the development of a UXO-MMMP. The

UXO-MMMP will be developed in consultation with the SNCBs and

included within the Marine Licence application.

When assessing disturbance associated with UXO clearance to harbour

porpoise within the cSAC the following worst case scenario was

considered: a maximum of 60 UXO clearance detonations and a 26km

EDR from each detonation which would fall wholly within the winter

component of the cSAC (due to uncertainty on location of the UXO). The

clearance is planed to take place over the period 1st November 2017 to

the 31st March 2018 with no UXO detonations occurring on the same day

as piling (despite the overlap in date ranges).

No more than two detonations per day are planned for non-piling days

with a separation distance not exceeding 5km. It is noted that additional

detonations may be required depending on confirmed locations of UXO, if

this is the case then the combined area affected in-combination will not

exceed 20% of the winter extents of the cSAC.

A worst case of 60 UXO clearance days occurring over the 2017/18

winter season in addition to the planned piling taking place between 10th

February and 31st March 2018 produces an average seasonal effect from

the project alone of 9%, under the SNCB seasonal threshold of 10%. It is

noted that in reality this effect will be less as not all detonation

disturbance would fall wholly within the cSAC. Should more than one

detonation occur over a 24 hour period then the seasonal disturbance

effect would reduce further.

Based on the information above, the Secretary of State considers that the

construction of East Anglia ONE alone will not result in an adverse effect

on the integrity of the cSAC from anthopogenic underwater sound from

UXO clearance by detonation and percussive piling.He places weight on

the above assessment of piling and UXO clearance activity, which

15

demonstrates that the percentage area of the SNS cSAC impacted is

below that considered by the SNCBs to be significant. The Secretary of

State recognises that the specific requirements for UXO detonation is not

yet known; however he takes sufficient comfort in view of the spatial and

timing restrictions committed to by EAOL.

The Secretary of State concludes that the anthropogenic underwater

sound from the construction of the project alone will not result in

adverse effect on the integrity of the cSAC.

In-combination impacts of other known or potential activities

Consideration must be given to the in-combination effects on the cSAC of other plans or

projects. Consideration is given to sources of anthropogenic underwater sound that have the

potential to contribute to an in-combination effect on harbour porpoises.

The plans and projects screened in for assessment of in-combination impacts are limited to

those meeting the following criteria and are anticipated to occur within the winter 2017/18,

summer 2018 and winter 2018/19 seasons:

Percussive piling activity within 26km of the cSAC

UXO clearance activity with 26km of the cSAC

Oil and gas activities of seismic surveys up to 10km of the cSAC or piling within 26km of

the cSAC

Table 6: Plans or projects considered in the in-combination assessment8

Plan or Project Activity timescale

East Anglia ONE UXO clearance during the period 1st November 2017

31st March 2018

East Anglia ONE Percussive piling during the period 10th February

2018 - 31 October 2018

Triton Knoll Construction window of 2017 to 2021; piling to occur

at some point within that window.

Hornsea Project One Percussive piling during the period February 2018 -

May 2019, with UXO clearance planned summer

2017

Hornsea Project Two Construction window of January 2017 to December

2021; piling to occur at some point within that window.

Dogger Bank and Creyke Beck A&B Construction window of 2017 to 2021; piling to occur


Dogger Bank and Teeside A&B Construction window of 2017 to 2021; piling to occur


8 Scottish Power Renewables – Requirement 36 Report, August 2017 EA1-CON-B-GBE-23782; Table 13 and

Table 14

17

Oil and gas licence proposals 12 oil and gas consent applications for seismic

surveys were identified. Of those only 3 have been

granted consent and all of those have a survey

consent end date of end of 2017. Out of the 12

application blocks only one overlaps the winter

portion of the cSAC.

UXO clearance Assumption that some level of UXO clearance activity

may occur on an annual basis.

Ad hoc precautionary works at Galloper UXO clearance was completed in 2016, however

potential remains for ad hoc removal of UXO

clearance if required. Potential for a precautionary

post installation geophysical survey

Fisheries

Bycatch of harbour porpoise in fishing gear is reported to be one of the most significant

anthropogenic pressures impacting on the harbour porpoise population[1]

The majority of fish landings are obtained from areas adjacent to the cSAC but there are

relatively low levels of fishing activity within the cSAC[2]. While commercial fishing is

considered capable of forming a plan or project under the Habitats Directive, there are no

known plans or projects that will increase the current level of fishing activity within the cSAC.

Commercial fishing has a long historical presence within the cSAC and any impacts on the

harbour porpoise population as a result of commercial fisheries are considered to be a

component of any environmental baseline. Furthermore, it is not possible to determine what

the baseline conditions would be without the impacts that fishing activities have on the harbour

porpoise population.

For the purposes of this assessment, on-going impacts from current activities that have a long

historical presence within the cSAC have been captured as part of the environmental baseline

against which the assessment has been carried out and are not considered to be significantly

affecting the harbour porpoise population, which is in favourable condition. For this reason,

effects from current fishing can be ruled out of this in-combination assessment.

[1]

JNCC report 566, December 2015. A Conservation Literature Review for the Harbour Porpoise (Phocoena phocoena). IAMMWG, Camphuysen, C.J. & Siemensma, M.L.

[2] MMO 2014, UK Sea Fisheries Statistics 2014.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/598190/UK_Sea_Fisheries_Statistics_2014_full_report.pdf



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Tiered approach

A two tiered approach was taken for the assessment which accounts for the level of certainty

on the construction timetable of individual projects. Tier 1 projects are those with a contract for

difference (CfD) and financial investment decisions (FID) in place or have a high degree of

certainty on construction timetables. Tier 2 projects have a consent in place but are yet to

secure CfD or FID and do not have a timetable of works available.

As the average time from securing a CfD to construction commencing is around 2 years with at

least 18 months elapsing between FID and construction of the first piles, it is reasonable to

consider with some degree of certainty that the Tier 2 projects are unlikely to overlap with East

Anglia ONE’s construction window.

Of the projects listed in Table 6, the following are Tier 1 and will be taken forward in the in-

combination assessment:

East Anglia ONE (UXO clearnance)

East Anglia ONE (piling)

Hornsea Project One (piling)

Oil and gas seismic surveys (3 surveys which are consented to be completed by end of

2017)

Table 7: In-combination assessment for Southern North Sea cSAC

Pressure Interest

Feature

Favourable condition target for relevant attribute (including range of natural variation) based on conservation objectives

Contribution of management or other unauthorised sources to attribute and /or feature condition

Adverse effect of proposal alone on attribute and/or feature

Adverse effect of proposal in combination with other plans or projects, on attribute and /or feature

Can adverse affects be avoided?

Adverse affect on integrity (long term or short term) (yes, no or uncertain)?

Anthropogenic underwater sound




Winter 2017/18

For the winter 2017/18 season in-combination assessment, EAOL made

the following worst case scenario assumptions:

UXO clearance of up to 60 detonations with an assumed EDR of

26km for 60 days across the season, with all 26km EDRs

occurring wholly within the cSAC. No UXO clearance related to

East Anglia ONE occurring on piling days

Up to 15% of the total piling commitment for East Anglia ONE.

For other windfarm projects the maximum footprint of effect per

project is calculated based on a 26km EDR drawn at the location

that would cause the largest overlap with the cSAC

60 days of oil and gas seismic survey during 2017 with an EDR of

10km drawn to have the maximum overlap with the cSAC.

Assuming a worst case scenario of installation of up to two piles or UXO

detonations (non-concurrent) and other projects concurrent, a maximum

spatial effect of no more than 20% in a 24 hour period is predicted for

both the 2017 and 2018 portions of the winter season.




20

Summer 2018

For the summer 2018 season in-combination assessment, EAOL made


Up to 80% of the total piling commitment for East Anglia ONE

(248 piles). For other windfarm projects the maximum footprint of

effect per project is calculated based on a 26km EDR drawn at

the location that would cause the largest overlap with the cSAC

For Hornsea Project One the piling would occur within the same

24 hour period as at East Anglia ONE and at the foundation

location(s) leading to the maximum overlap of the EDR.

UXO clearance will not occur in relation to East Anglia ONE but

may be necessary for other projects.

A worst case EDR of 26km produces an in-combination spatial range

effect over a 24 hour period of 8% of the summer extent of the cSAC.

Winter 2018/19

For the winter 2018/19 season in-combination assessment, EAOL made


Up to 5% of the total piling commitment for East Anglia ONE (15

piles). For other windfarm projects the maximum footprint of

effect per project is calculated based on a 26km EDR drawn at

the location that would cause the largest overlap with the cSAC

UXO clearance will not occur in relation to East Anglia ONE but

may be necessary for other projects

Assuming a worst case scenario of installation of up to two piles and

other projects concurrent, a maximum spatial effect of no more than 20%

in a 24 hour period is predicted for the winter 2018/19 season.

It should be noted that the in-combination effects predicted above are

based on the more precautionary generic EDR of 26km and still remain

21

under the SNCB recommended threshold of 20% effect within 24 hours.

The project specific EDR of 19km produces lower estimates of in-

combination effect.

EAOL considers that UXO clearance from other European countries

which could contribute to an adverse effect on the integrity of the cSAC

in-combination is deemed to be de minimus. The reasons for this

conclusion are: only five relevant UXO were detonated in 2014, there is

an expectation this number will decrease, any UXO detonated would

need to be within the 26km EDR to contribute to effects on the cSAC and

the UXO detonation would need to coincide within 24 hours of another

activity (for the 20% threshold) and sufficiently overlap the relevant

seasonal extent of the cSAC (for the 10% threshold).

Seasonal in-combination effects

The in-combination effects of East Anglia ONE across the winter 2017/18,

summer 2018 and winter 2018/19 seasons were based on the

precautionary assumptions set out above (for the 24 hour in-combination

effects).

For the worst case generic EDR of 26km the effects per season were

estimated as no more than 10% for winter 2017/18, 6% for summer 2018

and 3% for winter 2018/19. The project specific EDR of 19km produced

lower estimates of seasonal effects.

The Secretary of State concludes that the anthropogenic underwater

sound from the construction of the project in-combination with

other plans and projects will not result in adverse effect on the

integrity of the SNS cSAC. He places weight on the above assessment

of piling, UXO clearance and oil and gas seismic operations, which

demonstrates that the percentage area of the SNS cSAC impacted is

below that considered by the SNCBs to be significant. The Secretary of

State recognises that future UXO activity in the Southern North Sea is not

22

currently known; however he takes sufficient comfort in view of the spatial

and timing restrictions committed to by EAOL and in the knowledge that,

should UXO clearance be required in UK waters for other campaigns, this

activity would be subject to a separate licencing regime, which must also

must comply with Articles 6(3) and 6(4) of the Habitats Directive.

Proposed Mitigation

A summary of all proposed mitigation measures was submitted by EAOL9 and was taken

into account prior to the Stage 1 Assessment. The proposed mitigation measures are as

follows:

Exclusion of monopiles from the project design

A MMMP Procedure which includes the use of ADDs, marine mammal observers

and soft start procedures

Limiting piling activity to 10th February 2018 to 31st October 2018

No concurrent piling activity for wind turbine foundations

Where sequential piling is necessary, limiting piling to two locations in a 24 hour

period

Where sequential piling is necessary, limiting the separation distance of piling

locations to no more than 8km during the winter period (October to March)

No piling on the same day as UXO clearance

If two UXO clearances are necessary in a 24 hour period, the separation will not

exceed 5km

These mitigation measures are considered to be sufficient to reduce the risk of PTS or

TTS and minimise disturbance to levels under the SNCB recommended thresholds.

Monitoring

It is noted that the following monitoring is proposed by EAOL:

During construction, subsea noise monitoring will take place during piling at the first

four WTG foundation locations and also at the OSS. The overall objective of

monitoring noise generated during construction is to validate the predictions made

in the EA ONE Environmental Statement. If the underwater nolise from piling is

measured to exceed modelling predictions in the Environmental Statement then the

MMO has powers to suspend the EA ONE Marine Licence under section 72(3) of

ther Marine and CoastaL Access Act 2009

Monitoring by marine mammal observers during the installation of WTG and the

OSS. Monitoring will include marine mammal observers recording details of

acoustic and visual monitoring efforts, sightings/behaviour of marine mammals

9 Scottish Power Renwables - Summary of MMMP Mitigation Measures (Document submitted to fulfil

Requirement 36 of The East Anglia ONE Offshore Wind Farm (Corrections and Ammendments Order) 2016) – November 2017

Assesment

24

observed, mitigation activities (including soft start and ADD use) and piling activity

details (including start, end times, problems encountered etc).

These monitoring measures are considered adequate for the purposes of requirement 36.

Conclusion

Will the plan or project cause an adverse effect on site integrity (long term or short

term)?

After having had regard to the best available evidence, the Secretary of State concludes

that, considering the above mitigation measures and the commitments which are secured

through the MMMP to be implemented under Requirement 36 of the DCO, there is no real

risk of the plan or project causing an adverse effect on site integrity for the Southern North

Sea cSAC.

Assesment

25

PAGE DELIBERATELY LEFT BLANK

Appendix 1 – Record of comments received during consultation period

26


Project-specific comments made by: Response:

1. The Wildlife Trusts

The science underpinning the proposed SNCB thresholds is inadequate and therefore not precautionary enough.

The Wildlife Trusts position is noted. For this application, the SNCBs recommended that SPR use temporal and spatial thresholds to determine adverse effects on the SNS cSAC. For the purpose of this assessment, we consider the SNCB advice is based on the best available evidence at the time of this assessment.

The JNCC MMMP guidance is no longer fit for purpose as it was developed for much smaller wind farms and does not take into account the conservation objectives for harbour porpoise cSACs.

We have not been provided with evidence that the JNCC guidance is not fit for purpose for larger windfarms. Furthermore, the MMMP procedure (which largely follows the JNCC guidance) constitutes just one part of the overall MMMP which we consider sufficiently discharges Requirement 36.

Following a legal challenge on a previous offshore windfarm DCO application, TWT consider that commercial fishing should be considered a plan or project and included in the appropriate assessment.

The ‘Fisheries’ section on page 17 addresses the in-combination consideration of bycatch from commercial fishing.

TWT appreciates that participation in the DEPONs project has become a standard condition of some wind farm marine mammal monitoring but believe that site specific monitoring is now required to ensure mitigation is suitable in meeting the conservation objectives of the cSAC.

Longer term strategic monitoring requirements including participation in the DEPONS project were considered and finalised as part of the original East Anglia ONE DCO application. We consider that as set out in the ‘Monitoring’ section on page 23 of this AA the proposed monitoring measures are adequeate for the discharge of Requirement 36. As noted below, we consider the monitoring of the first four wind turbine foundations sufficient to validate the underwater noise predictions made in this assessment.

Now that the SNS cSAC is in place, noise monitoring should occur throughout the whole

The monitoring of the underwater sound produced during installation of the first four foundations is standard


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construction period rather than the first four piles in to assess impacts on the SNS cSAC.

practice as a monitoring requirement for offshore windfarms. This monitoring requirement is considered sufficient to compare measurements to underwater sound modelling submitted by EAOL as part of the DCO application.

2. Whale and Dolphin Conservation

In response to the consultation on this Draft Record of Appropriate Assesment, the WDC submitted the same responses provided to EAOL on the Requirement 36 Report.

The points raised in the WDC submissions are addressed by EAOL in Appendix D of the Requirement 36 report. The Secretary of State is satisfied that EAOL have sufficiently addressed the WDC’s concerns.

3. MMO

Soft Start levels may not be possible to perform if the piling is interrupted. Has East Anglia One considered this issue, and what mitigation they have in place should this approach not be possible?

EAOL have considered the possibility of soft start not being possible following a break in the piling operation. The procedure which will be followed in this instance is set out in paragraph 19 of the MMMP Procedure (Appendix A of the Requirement 36 Report). In the event of a break in piling operation where it is not technically possible to recommence the piling with a soft start procedure, or if piling had stopped for a period greater than 10 minutes an ADD will be deployed for 15-30 minutes. MMOb and PAM operators will also maintain a watch throughout any break in piling operations to ensure no marine mammals are present within the mitigation zone before piling recommences.

We note that Unexploded Ordinance clearance will be covered in a separate licence application.

Noted.

4. Natural England and JNCC

NE welcome EA ONE’s plan to restrict the number of foundations piled and UXO detonations to 2 a day and as close together as possible.

NE’s advice to the regulator is that no other activity resulting in disturbance should be consented in the winter area between now and the end of March 2018 if it could fall on the same days as EA

Noted.

This advice will be shared with the MMO in their capacity as a marine regulator.


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ONE’s piling and UXOs operations.

NE’s advice to the regulator is that no other activity resulting in disturbance should be consented in the winter area between now and the end of March 2018 unless it can be proven that it will not push the seasonal average beyond 10% and (as above) does not fall on the same days as EA ONE’s piling and UXOs operations.

Noted, this advice will also be shared with the MMO in their capacity as a marine regulator.

With regard to the use of pin piles being considered a mitigation measure there is no evidence that disturbance effects are significantly different based on the size of the piles or hammer energy.

It should be noted that although EAOL undertook project specific noise modelling which indicated an effective displacement range (EDR) of 19km, the assumptions of this HRA are based on a precautionary EDR of 26km which is used as standard for monopile wind turbine foundations.

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