north east greenland 2016 seismic survey -...

North East Greenland

2016 Seismic Survey

Final Draft Scope of Works

Prepared for: TGS-NOPEC Geophysical Company ASA

NE Greenland Seismic Survey 2016 TGS

CMACS: J3293 TGS (NEG16 Scoping) v2

Document: J3293 TGS (NEG16 Scoping) v2

Version Date Description Prepared by Checked

by

Approved by

1 26/11/15 Pre Scope IGP/PC CH/KS IGP

2 21/12/15 Final Draft Scope IGP CH IGP

This report has been prepared by Centre for Marine and Coastal Studies Ltd (CMACS).

Contact Details:

CMACS Ltd 80 Eastham Village Road

Eastham

Wirral

CH62 0AW

UK

Company No 4883990 Tel: +44 (0)151 3277 177

[email protected]

www.cmacsltd.co.uk

TGS Lensmannslia 4 N-1386 Asker, Norway Tel: +47 66 76 99 00 Fax: +47 66 76 99 10 Postal Address: P.O. Box 154, N-1371 Asker, Norway www.tgs.com

mailto:[email protected]


http://www.cmacsltd.co.uk/

http://www.tgsnopec.com/



Contents

1. INTRODUCTION ................................................................................................. 1

1.1 Overview of Planned Survey ......................................................................... 1

1.2 Survey Licence Application ........................................................................... 2

2. DESCRIPTION OF THE PROPOSED ACTIVITY ............................................... 5

2.1 Licence number and licencee ........................................................................ 5

2.2 Overview of vessels ...................................................................................... 5

Seismic survey (Source) vessel .......................................................................... 6

Support Operations and Other Survey Work ....................................................... 6

2.3 Phase 1 (seabed sampling survey with MBES and SBP) ............................. 7

2.4 Phase 2 (Seismic survey) ............................................................................. 8

2.5 Support equipment ........................................................................................ 8

3. PURPOSE OF OPERATION AND PROPOSED SPECIFICATION..................... 9

3.1 Purpose .......................................................................................................... 9

3.2 Proposed Specifications (MBES and SBP survey) ......................................... 9

3.3 Proposed Specifications (airgun survey) ........................................................ 9

3.4 Proposed Specifications (seabed survey) .................................................... 14

3.5 Proposed Specifications (ice tracking buoys) ............................................... 15

3.6 Operation period ......................................................................................... 16

3.7 Placement of construction/equipment ......................................................... 16

3.8 Logistics of operation .................................................................................. 16

4. ENVIRONMENTAL ASSESSMENT .................................................................. 17

4.1 Overview ....................................................................................................... 17

4.2 Identification of Potential Impacts ................................................................. 19

Appendix 1. Survey Data Tables

AppendiX 2. MBES Equipment

Appendix 3. SBP Equipment

Appendix 4. Ice Buoys



Figures

Figure 1. Provisional NEG16 survey in relation to Seismic Protection Areas. ............ 3

Figure 2. Provisional NEG16 and previous (legacy) seismic survey by TGS of NE

Greenland. ................................................................................................................. 4

Figure 3. Typical 2-D seismic survey arrangement. ................................................... 8

Figure 4. Layout of the 3,350 cubic inch airgun array. ............................................. 11

Figure 5. Signal duration and associated pressure change for 3,350 inch array. ..... 11

Figure 6: Farfield signatures for 3,350 cubic inch array and a larger array required for

this survey). .............................................................................................................. 12

Figure 7: Cumulative energy flux per pulse. ............................................................. 12

Figure 8. Example of noise modelling sound exposure level (SEL) map.................. 13

Tables

Table 1. Contact details for vessel owners. ................................................................ 7

Table 2. Summary vessel details................................................................................ 7

Table 3. Seismic survey parameters. ....................................................................... 10

Table 4. Specifications for sampling equipment. ...................................................... 15

Table 5. Key dates in survey program. ..................................................................... 16

Table 6. Built-in mitigation. ....................................................................................... 18

Table 7. Built-in mitigation included in 2015 to be reviewed for 2016. ...................... 19

Table 8. Provisional list of potential impacts. ............................................................ 19

Table 9. Provisional list of potential impacts from seabed sampling work. ............... 21


CMACS: J3293 TGS (NEG16 Scoping) v2 Page 1

1. INTRODUCTION

1.1 Overview of Planned Survey

TGS-NOPEC Geophysical Company ASA (TGS) propose to undertake a seismic

survey off North East Greenland between 1 July and 31 October, 2016 (inclusive),

subject to favourable ice conditions. The survey is named ‘NEG16’.

The survey is planned in two phases:

Phase 1. Seabed sampling, supported by survey of bathymetry and surface

sediments using a multibeam echo sounder (MBES) and shallow substrata

using a sub-bottom profiler (SBP).

Phase 2. A 2D seismic survey using airguns (further details in Section 3).

Seabed sampling will cover several smaller areas within the wider survey area and

it is expected that up to 50 gravity cores and 100 dredge or grab samples would be

collected. Up to 10,000 line kilometres of 2D seismic survey data will be acquired

during Phase 2. In practice it is expected that fewer line kilometres of data will be

acquired since ice conditions are likely to limit the start and/or end of the survey.

However, the EIA will assess the full programme.

Proposed survey vessels include an ice breaker which will be required to allow survey

operations in these waters. Details on this and other proposed vessels are provided

in Section 2. A range of support equipment is also proposed to enhance operational

safety and survey efficiency (through improved ice management tools):

o Ice tracking buoys

o Helicopter

The Survey Area is presented in Figure 1 where the proposed 2D seismic survey

lines for 2016 are shown. These lines, and those in subsequent figures, are

provisional and may change following further planning work and/or through detailed

environmental impact assessment; however, all lines will be fully within the

boundaries of the Survey Area indicated and will not enter any of the closed areas

where seismic survey is prohibited. The provisional survey lines are not spaced

uniformly since the survey may target certain areas of interest in greater detail than

others. In a limited number of areas the spacing is around 1km, although adjacent

lines would be unlikely to be surveyed consecutively because of the limited turning

radius of the survey vessel. Throughout the majority of the survey area the line

spacing is 10km or more.



In addition to closed areas, areas of concern have been designated for various

marine mammal species (Figure 1) and will be a key focus of the assessment.

TGS have completed a number of previous surveys in the region. These are

summarised in Figure 2 where it can be seen that the intention is to survey largely in

areas which have been visited previously between 2011 and 2015 to increase the

quality and resolution of data. It is also intended to extend the survey to the north in

comparison to previous years, and further offshore in the north eastern part of the

survey area, should ice conditions permit.

1.2 Survey Licence Application

Guidance on the application and assessment process for seismic survey has been

downloaded from the Government of Greenland (Naalakkersuisut) website1.

TGS will submit an application for a Survey Licence to the Mineral Licence and

Safety Authority (MLSA). MLSA have reviewed a pre-scope and advised that an

Environmental Impact Assessment (EIA) will be required. The pre-scope has been

revised to address any initial comments from MLSA and is now issued as a final

draft scope for public consultation.

This Scope of Works provides information on the proposed surveys and planned

environmental assessment work requested by MLSA in guidelines for application,

execution and reporting of offshore hydrocarbon exploration activities (BMP, 20112)

and supplementary guidelines for EIAs concerning seismic surveys (BMP, 20123),

including Survey Data Tables (Appendix 1). Recently issued guidelines for

submission of scope of project for offshore hydrocarbon exploration activities

(MLSA, 20154) have also been reviewed and relevant information is provided here.

Since the pre-scope was drafted Environment Agency for the Mineral Resources

Activities, Greenland (EAMRA) have issued new guidelines for EIAs (EAMRA, 20155)

which include updated marine mammal protection areas referenced in this scoping

report.

1 https://www.govmin.gl/petroleum/environment/environmental-regulation (checked on 19 November, 2015). 2 BMP (2011). Guidelines for application, execution and reporting of offshore hydrocarbon exploration activities (excluding drilling) in Greenland. 3 BMP (2012). Supplementary guidelines for EIAs concerning seismic surveys in Greenland 2012. Appendix F: Guidelines for submission of scope of project for offshore hydrocarbon exploration activities (excluding drilling). 4 MLSA (2015) Guidelines for submission of scope of project for offshore hydrocarbon exploration activities. 5 EAMRA (2015) Offshore Seismic Surveys in Greenland. Guidelines to Best Environmental Practices, Environmental Impact Assessments and Environmental Mitigation Assessments.

https://www.govmin.gl/petroleum/environment/environmental-regulation



Figure 1. Provisional NEG16 survey in relation to Seismic Protection Areas.



Figure 2. Provisional NEG16 and previous (legacy) seismic survey by TGS of NE Greenland.



2. DESCRIPTION OF THE PROPOSED ACTIVITY

2.1 Licence number and licencee

Prospecting licence for an offshore area in North Greenland Licence: No. 2014/13 for North Greenland Licensee: TGS-Nopec Geophysical Company ASA Licence area: Offshore areas in North Greenland Licence period: 2014 – 2018 Contact details of licence holder:

TGS-NOPEC Geophysical Company ASA

Lensmannslia 4, N-1386, Asker, Norway

Sergej Usov

Tel: +47 6676 9900 Fax: +47 6676 9910

Knut Agersborg

Tel: +47 6676 9900 Fax: +47 6676 9910

Postal Address

P.O. Box 154 N-1371, Asker, Norway

2.2 Overview of vessels

TGS plan to use the seismic survey vessel M/V Akademik Shatskiy, or a similar vessel,

to undertake 2D seismic survey acquisition. The seismic survey vessel will be

supported by two further vessels, an icebreaker (e.g. the Otso or similar) and a support

vessel (e.g. the M/V Bjørkhaug or similar). It is planned to use the Bjørkhaug for Phase

1 survey work, i.e. MBES, SBP and sediment sampling.

The vessels have implemented safety systems that meet all requirements of the leading

companies in the oil industry. They are also insured in accordance with the

requirements standard for major oil companies.



Seismic survey (Source) vessel

The M/V Akademik Shatskiy is a Russian registered vessel owned by the Russian

geophysical company Sevmorneftegeofizika (SMNG). SMNG is the largest marine

geophysical company in Russia. It renders a wide range of marine geophysical services

worldwide including: 2D/3D marine seismic acquisition, navigation positioning, data

processing and integrated interpretation of seismic data.

TGS will operate the seismic survey vessel under a charter agreement with SMNG.

TGS will be responsible for maritime and seismic operations together with SMNG.

Akademik Shatskiy is an 83.5m, 3,211 gross ton vessel (Plate 1); it, or a similar vessel,

will be the survey vessel, towing airguns and hydrophone streamer.

Plate 1. M/V Akademik Shatskiy.

Support Operations and Other Survey Work

An icebreaker will escort the source vessel in areas where sea ice is present. The ice

breaker will also be required to escort the Bjørkhaug (or similar vessel) during Phase 1

survey work.

After completion of Phase 1 survey work the Bjørkhaug will become a support vessel to the seismic survey. A support vessel is needed for personnel rotations which will be via Longyearbyen on Svalbard or another suitable port and to provide safety cover offshore at other times.

Contact details for vessel owners are provided in Table 1 and summary vessel details

in Table 2. This information is provisional and will be confirmed in the EIA/EMA once

the vessel selection process is finalised.



Table 1. Contact details for vessel owners.

M/V Akademik Shatskiy

Sevmorneftegeofizika Trust (SMNG)

M/V Otso Arctia Shipping

M/V Bjorkhaug Maritim Management A/S

17, Karl Marx Str.

Murmansk 183025

Russia

Laivastokatu 9, FI-00160 Helsinki, Finland

Po. Box 370 Sentrum 6001 Aalesund Norway

Phone: 7 8152 476 397

Int Phone: 47 789 1042 8

Fax: 7 8152 456 049

Int Fax: 47 789 1042 7

Email:

[email protected]

Tel.: +358 30 620 7000 Email: [email protected]

Tel: +47 70 11 39 20

Fax: +47 70 11 39 21

E-mail:

[email protected]

NB the information above is provisional and will be confirmed in the EIA/EMA.

Table 2. Summary vessel details.

Vessel Vessel Type Call sign IMO MMSI

number

Contact number/email

M/V

Akademik

Shatskiy

Seismic Survey UAIR 8407010 273452600 TBC

M/V Bjørkhaug

Support Vessel (and

Phase 1 Survey)

JWYW3 8505472 258051000 TBC

M/V Otso Ice Breaker OIRT 8405880 230252000 TBC

NB the information above is provisional and will be confirmed in the EIA/EMA.

2.3 Phase 1 (seabed sampling survey with MBES and SBP)

MBES and SBP survey will be used to optimise the locations for direct sampling of the

seabed. This work will contribute to improved understanding of the survey area (see

Section 3.1). MBES and SBP use reflected sound energy to infer information on seabed

conditions relating to depth and surface geology and shallow sub-surface geology. This

survey will take place in the early part of the programme when ice conditions may be

difficult. Although an ice breaker will be present the survey may still be limited by

conditions and will work only in areas where this is safely practical.

The number and position of seabed samples is yet to be determined but it is anticipated

that up to 50 gravity cores and 100 additional samples (dredges or grabs) would be

collected and will be considered in the impact assessment.






2.4 Phase 2 (Seismic survey)

Offshore seismic survey involves transmitting acoustic energy to the seabed and

recording energy reflected back from subsurface boundaries to acquire information on

subsurface geology. Airguns towed by a survey ship are used to provide the acoustic

energy that is reflected to the towed hydrophone ‘streamer(s)’ some 5-12km long (Figure

3). Airguns fire repeatedly, typically every 10 seconds, and produce very short duration

bursts of sound. Most energy in seismic surveys is produced under 200Hz with a peak

typically around 20-120Hz.

Figure 3. Typical 2-D seismic survey arrangement (source: The Open University, 2014).

2-D seismic survey, as planned for NEG16, involves a single towed streamer (hydrophone

array). This contrasts with 3-D seismic survey which use multiple towed streamers. A 2-

D survey is typically used to provide a regional dataset that allows many companies and

other stakeholders insight to the hydrocarbon potential of a region as a whole rather than

smaller areas typically covered by 3-D surveys.

2.5 Support equipment

In order to provide information on the drift of extreme ice features / icebergs in NE

Greenland TGS plans to deploy ice tracking buoys to support operations as well as wider

academic research into ice drift patterns in the NE Greenland area. Operationally,

monitoring ice drift in real-time will allow the survey team to better establish drift patterns

and potentially forecast clearing areas ahead of seismic survey. The drift patterns may

also permit TGS to forecast ice pressure development where there are multiple buoys

deployed in one area. The drift data collected will contribute to the understanding of

http://openlearn.open.ac.uk/mod/resource/view.php?id=172129



longer-term trends and perhaps seasonal variations, once sufficient data is collected.

Increasing knowledge of extreme ice features and drift patterns will have short term gains

for acquisition efficiency and make a long term contribution to environmental

understanding. Seven ice tracking buoys were deployed during the NEG 2015 survey

and a similar programme is currently envisaged for 2016, although TGS will investigate

using more buoys since the ice tracking data proved valuable for daily survey planning

and helped make the operation safer.

3. PURPOSE OF OPERATION AND PROPOSED SPECIFICATION

3.1 Purpose

The overall purpose of the project is to acquire multi-client seismic data to meet operator

work program commitments in licensed acreage and to develop a regional grid over

unlicensed blocks for any future licence rounds.

The data acquired by the phase 1 and 2 surveys will contribute to a more accurate and

advanced understanding of the geology and hydrocarbon potential of the area. By

conducting the project as a multi-client project, it will eliminate (or significantly reduce)

the need for the various exploration companies to acquire the same data

independently and thereby limit the overall impact to the environment.

3.2 Proposed Specifications (MBES and SBP survey)

A Sonic 2026 multibeam echo sounder (Appendix 2) is planned to be used. The source

sound level of the MBES is variable but will be a maximum of 221dB re 1μPa @ 1m. A

frequency range of between 200 and 400kHz will be used.

An Innomar SES-2000 medium -100 parametric sub-bottom profiler (Appendix 3) is

planned to be used. The source sound level of the SBP will be a maximum of 247dB re

1μPa @ 1m. The pulse type of SBP equipment is variable but a constant wave (CW)

signal is planned to be used with a single frequency primary wavelength of 100kHz

(available range is between 85 and 115kHz).

3.3 Proposed Specifications (airgun survey)

The survey is to be undertaken using the parameters set out in Table 3 which are

equivalent to previous surveys by TGS off NE Greenland since 2011. There will be an

array of 16 (2 x 8) active guns with a total active volume of 3,350 cubic inches.

Noise measurements made during the NEG15 survey will be used to refine information

on the characteristics of the airgun source. For present purposes the information



presented below is based on previous survey acquisition reports.

Airgun array layouts are detailed in Figure 4. The total operating airgun pressure will

be a maximum of 2000 PSI and the peak to peak pressure approximately 90 bar-m.

The duration of each airgun ‘shot’ and associated pressure change is presented in

Figure 5 and signal frequency characteristics in Figure 6. Information on the energy

transmitted with each pulse is provided in Figure 7. This information is important to

understand the characteristics of the underwater noise produced during the survey so

that modelling work can be undertaken to support assessments of its likely effects on

marine wildlife such as fish and marine mammals. Examples of the output of noise

modelling work are provided in Figure 8.

The vessel will conduct the survey whilst travelling at around 5 knots with a firing

interval of 10 seconds (firing approximately every 25m). The survey vessel is intended

to be operational 24 hours a day except in periods when weather or other conditions

do not allow for data acquisition.

Table 3. Seismic survey parameters.

Parameter Value

Number of active air guns 16

Total active volume (cubic inches) 3350

Length of array/Inline spread (m) 19

Width of array/Crossline spread (m) 6

Total pressure (psi) 2000 ±10%

Peak to peak Pressure (bar-m) 90

Planned source depth (m) 7-9

Vessel speed (knots) 5

Firing frequency (s) 10

Firing interval (m) 25



Figure 4. Layout of the 3,350 cubic inch airgun array.

Figure 5. Signal duration and associated pressure change for 3,350 cubic inch array.



Figure 6: Farfield signatures for 3,350 cubic inch array (blue) and a larger array (red- not required

for this survey).

Figure 7: Cumulative energy flux per pulse (similar array to that proposed for NEG16).



Figure 8. Example of noise modelling sound exposure level (SEL) map for: top, one airgun array shot, where the SEL is shown using colours, warm colours being a high SEL, and cold colours represent a low SEL; bottom, cumulative noise exposure modelling (sound exposure level for pinnipeds in water).



3.4 Proposed Specifications (seabed survey)

The seabed sampling programme will comprise up to approximately 150 benthic sites

(estimated 50 gravity core and 100 dredge or grab samples) and is due to be undertaken

by the Bjørkhaug during Phase 1.

The methodology for this is based on seabed sampling surveys conducted by TGS in

Baffin Bay during 2008 and 2011 and NEG in 2012 and 2013. Sampling will be conducted

to investigate areas where seismic reflections are truncated, these are usually areas

where steep shelves and slopes are present. The survey is designed to provide additional

information that can assist the seismic survey data acquisition in identifying geological

features and seabed types. Gravity corers are also used on potential seep locations which

tend to be depressions in the seabed.

The following information (Table 4) is provided in accordance with NORSOK sampling

standards and describes the equipment used.



Table 4. Specifications for sampling equipment (NORSOK ANNEX B, 2004).

Aspect Parameters for survey (approximate)

Type of Sediment expected Soft clay and rock samples

Type of equipment used Gravity corer and dredge/grab

Weight of equipment in air Gravity corer: 800 kg – dredge/grab: 100 kg

Deck space required 8 x 4 m

Crane lifting force and arm length No crane needed during operations

Manufacturer of equipment OSIL (osil.co.uk)

Limitations (water depth, soil type) Cable length, stiffness of seafloor sediments

Geometry and dimensions of cutting shoe Hollow cylinder, inner/outer diameter, 90/100 mm

outer diameter.

Inside diameter of core barrel and liner 94/86 mm

Outside diameter of core barrel and liner 100/90 mm

Whether a piston is used No piston will be used

Weight and lengths available 3 m core barrel

Special handling requirements, e.g. free fall

mechanism.

Winch with free fall

3.5 Proposed Specifications (ice tracking buoys)

It is currently anticipated that approximately eight Polar iSVP ice tracking buoys (Appendix

4) will be deployed. It is intended to retrieve and redeploy all buoys but consideration will

be given in the assessment for the environmental consequences should recovery of all

buoys not be possible. Six out of seven buoys deployed in 2015 were recovered

successfully.



3.6 Operation period

The survey programme is summarised in Table 5.

Table 5. Key dates in survey program.

Activity Date

Arrival in Greenland waters

(earliest)

01/07/2016

Start of seismic data acquisition

(earliest)

01/07/2016

Completion of seismic data acquisition

(latest)

31/10/2016

Start of seabed survey (earliest) 01/07/2016

Completion of seabed survey (latest) 31/10/2016

3.7 Placement of construction/equipment

No placement of equipment is planned other than the use of surface buoys to monitor ice flows which it is intended will be recovered.

3.8 Logistics of operation

The initial port of mobilisation is planned to be Tromsø, there will be the option to use

Bergen (Norway), Lerwick (UK), Longyearbyen (Svalbard) or Reykjavik (Iceland) if the

survey vessels require port facilities or shelter. Crew changes, if required, will be done

from either Longyearbyen or Reykjavik using the support vessel. The helicopter will be

based on the icebreaker and is intended for ice scouting only.

Bunkering and resupplying arrangements are planned and will be be performed by the

support vessel, if necessary with the additional support of a specialized bunkering

vessel. All waste will be retained and disposed of at facilities onshore.



4. ENVIRONMENTAL ASSESSMENT

4.1 Overview

A key purpose of the Scoping Report is to identify potentially significant environmental

impacts of the proposed survey. Impact receptors, i.e. groups potentially affected, could

include marine wildlife such as seabirds or marine mammals, or other users of the survey

area such as commercial fishing activity for example.

Section 4.2 summarises identified potential impacts which it is intended will be

considered in more detail should EIA be requested. Because equivalent survey

operations have been undertaken in previous years it is considered unlikely that

significant impacts which could not be reduced to acceptable levels through mitigation

would exist. Equally, because there have been a number of consecutive surveys in the

same general area the potential for cumulative effects will be considered in the impact

assessment.

As is the case for previous surveys off Greenland by TGS, relevant statutory guidance will

be followed to minimise environmental impacts. Certain mitigation arrangements which

have been developed for previous surveys in the area will also be adopted again and

together this represents ‘built-in’ mitigation which will be taken into account in the

environmental impact assessment. Planned built in mitigation, above and beyond

compliance with standard good environmental practice and national/international

environmental legislation, is set out in Table 6.

Underwater noise modelling has been undertaken previously based on both larger

arrays than planned for NEG16 and the 3,350 cubic inch array proposed. The

assessment will also be supported by measurements of underwater noise from the 3,350

cubic inch array which were made during the NEG 2015 survey. Results of this work

will be used to confirm the validity of previous noise modelling, which it is proposed will

be used again to inform the assessments for NEG16 provided it can be shown that this

modelling did not understate potential effects.



Table 6. Built-in mitigation.

Potential Impact Built-in Mitigation Notes

Conflicts with other vessels (e.g. fishing, commercial traffic).

Support (chase) vessel to liaise via radio to alert other vessels to activity and avoid conflicts.

Disturbance of marine mammals/seabirds by survey vessels and aircraft.

Helicopter pilot to have instructions to avoid flying low (<500m) over marine mammals when detected, or aggregations of seabirds if at all possible and never to deliberately hover over or approach any marine mammals (including polar bear and seals) or seabirds.

Survey vessels to avoid marked changes of speed or direction when operating in vicinity of marine mammals, unless avoidance action is required.

Injury and disturbance to marine mammals from airgun noise.

During and around airgun firing operations guidelines detailed in EAMRA (20156) will be followed.

Guidelines will be implemented by a team of 4 marine mammal and seabird observers (MMSOs) following guidelines provided by Johansen et al (20127). Passive acoustic monitoring (PAM) will be implemented at all times (by two PAM operators working shifts) and two MMSOs will undertake visual surveillance during daylight hours.

Injury and disturbance to bowhead whale

MMSOs will be especially aware of the potential for bowhead whales to occur and will act in a precautionary manner if the animals are known to be in the area. If possible the survey will move away from any area where bowheads have been reported to be active to a distance of at least 50km with survey commencing away from the area in question

Having reviewed the pre-scope EAMRA’s advisors DCE/GINR have stated that this mitigation is considered as important and should be retained.

Contamination of waters Hydrophone streamer cables to be solid, not fluid filled.

The requirement for some mitigation which has been applied in previous surveys will be

evaluated again before mitigation is finalised for 2016 (Table 7).

6 EAMRA (2015) Offshore Seismic Surveys in Greenland. Guidelines to Best Environmental Practices, Environmental Impact Assessments and Environmental Mitigation Assessments. 7 Johansen KL, Boertmann D, Mosbech A & Hansen TB (2012) Manual for seabird and marine mammal survey on seismic vessels in Greenland. 3rd revised edition, May 2012. Aarhus University, DCE – Danish Centre for Environment and Energy, 74 pp. Scientific Report from DCE – Danish Centre for Environment and Energy No. 38



Table 7. Built-in mitigation included in 2015 to be reviewed for 2016.

Potential Impact Built-in Mitigation (2015) Notes

Disturbance to walrus The survey will maintain a minimum 2.5km distance from any closed area for walrus. No firing will take place at a distance closer than this to the walrus closed areas

Information from noise measurements in 2015 will be used to determine if this mitigation is necessary in 2016.

4.2 Identification of Potential Impacts

A provisional outline of receptors potentially affected by the seismic survey (airguns,

SBP, MBES and other equipment) is provided in Table 8, below. Impact assessments

will be completed taking into account that built-in mitigation (Table 6) would be in place.

Any additional mitigation necessary will be identified following comprehensive

assessment.

It is currently unknown whether any other seismic surveys are planned to be conducted

at the same time. TGS will wait for advice from the Greenland authorities and will prepare

a cumulative assessment with appropriate mitigation if required.

A cumulative assessment will also be undertaken to consider the effects of multiple years

of seismic survey off NE Greenland on receptor groups, notably marine mammals which

are identified as the most sensitive to disturbance from underwater noise.

Table 8. Provisional list of potential impacts from acoustic survey operations and related activities.

Receptor

Anticipated Impacts and Mitigation

Water Quality The threat to fish from accidental spills, e.g. of oil/fuels, and materials within

vessels, helicopter and ice buoys and will be assessed. Mitigation commensurate with identified risks will be developed if appropriate.

Fish The key potential impact is underwater noise and sensitivities of fish will be

assessed in relation to known distributions, including seasonal considerations in

relation to spawning. Underwater noise modelling will support the assessment.

The threat to fish from accidental spills, e.g. of oil/fuels, and materials within vessels and ice buoys and will be assessed. Mitigation commensurate with identified risks will be developed if appropriate.



Receptor

Anticipated Impacts and Mitigation

Sea Birds Analysis of potential sensitivities will be conducted as part of the EMA/EIA

process. The survey is largely well offshore but at certain locations potential survey

lines approach relatively close to shore. Overall risks are anticipated to be minimal

with the main risk being oil spills which could reach the coast. The potential for

birds which forage away from the coast to be affected, including through

underwater noise and the influence of vessel lighting, will be considered.

Disturbance by helicopter will be considered. The potential for marine

contamination to result from release of materials within ice buoys (if not retrieved)

will also be considered.

Mammals Marine mammals are a particular concern when considering seismic survey

impacts. In the extreme, underwater noise from airguns a t c l o s e r a n g e can

cause physical harm and hearing damage, and at greater range disturbance and

temporary displacement. Potential effects on animals both in the water and on ice

flows will be considered.

The survey surrounding areas will be carefully assessed for marine mammal sensitivities during the EIA/EMA. It is expected that with built-in mitigation the risk of physical injury to marine mammals will be minimal but this will be evaluated carefully and additional mitigation identified if appropriate.

The assessment will also include consideration of potential long-range disturbance effects as well as the risk of impacts from accidental oil spills and collision with vessels.

Potential for disturbance by helicopter and will be considered.

The assessment will also evaluate the potential for marine contamination to result from release of materials within ice buoys (if not retrieved).

The assessment will be supported by underwater noise modelling completed for previous survey operations off NE Greenland which will be additionally supported by information from underwater noise measurements made during the 2015 survey.

Human Activities

Potential impacts on commercial fisheries (e.g. trawlers) will be assessed based

on the above mentioned assessment for fish as well as in relation to possible

conflict between the survey vessels and fishing vessels using the same waters.

The potential impact on small scale subsistence fishing (small boats) and hunting will be considered.

The impact on tourism is anticipated to be negligible but this will be considered in more detail within the assessment.

Potential impacts from seabed sampling work are outlined in Table 9.



Table 9. Provisional list of potential impacts from seabed sampling work.

Receptor Anticipated Effect

Fish Seabed sampling is expected to have a negligible effect on demersal fish communities. Impact analysis will be provided in EIA/EMA report.

Seabirds No impact anticipated.

Marine mammals

There is no impact to marine mammals anticipated from this activity.

Benthic habitats

There will be a small amount of disturbance to the seabed due to the nature of the survey. Impact assessment will be provided in the EIA/EMA report.

Human Activities

As the impact on demersal fish communities is anticipated to be negligible, the impact on commercial fisheries is likewise anticipated to be negligible. Impact analysis will be provided in EIA/EMA report. There is no impact anticipated to fishing, hunting or tourism.


CMACS: J3293 TGS (NEG16 Scoping) v2 Appendix 1, page 1

APPENDIX 1. SURVEY DATA TABLES

A. Survey data table (Overview)

Specify Description Provided

Type of survey (2D, high resolution (3D), well testing, other)

2D Seismic

Seabed sampling Geophysical (multibeam echo sounder and sub-bottom profiler)

Yes

Map of the area with all transect lines shown Figure 1 shows provisional survey lines

Yes

Start and end dates for the survey Start 01/07/2016

End 31/10/2016

Yes

Expected duration Up to 4 months Yes

Duty cycle of operation (in hours/24 hours)

Number of hours in the dark per 24 hours

24 hour operations

15/08/2016= 8hrs of dark

15/10/2016=15 hours of dark

Yes

Intended use of icebreakers Yes Yes

Will survey be carried out in ice? Ice is expected in considerable

areas of proposed survey area.



B. Array Specification


Number and names of vessels

towing airgun arrays

One (provisionally Akademik

Shatskiy)

Yes

For each vessel provide geometric

layout of complete airgun array with

individual volume specified (in PSI

per airgun and in3 per airgun)

See Figure 4. Yes

Size of total array (In3 and PSI

for the entire array)

2 x 8 gun array,

3,350 cubic inch.

2,000 PSI

Yes

Firing rate in shots/sec

Will sub arrays fire simultaneously or

alternate?

1 per 10s, 25 m per shot

Single stream most likely scenario

Yes

Operation speed of the vessel in

km/hours or knots.

5 knot towing speed Yes



C. Acoustic Properties of Airgun Array


Far field pressure signature of total

airgun output (provide figure)

Please see Figure 5. Yes

Frequency spectrum of the far field

airgun signature (broadband)

(provide figure)

Figure 6: Frequency spectrum Yes

Source level (source factor) of

airgun array on acoustic axis below

array, given in all of the following

units:

dB re 1 µPa peak- peak (broadband)

259 (3,350 cu in)

NB the above and other

expressions of source level

below may be revised when

analysis of 2015 noise

measurement data is complete

Yes

dB re 1 µPa rms

(Over 90%* pulse duration)

(provide duration

for rms calculation) *as defined in Malme et al., 1986; Blackwell et al., 2004

229 (3,350 cu inch) Duration for RMS calculation is 280ms

Yes

dB re: 1 µPa2s. per pulse 234 (3,350 cubic inch array) Pulse length is 280ms (see above)

Yes

Energy, joule/m2 per airgun pulse See Figure 7. Yes

Signal duration

(Define how it is measured)

400msec (peak response over

less than 30msec) (measured

from Figure 5)

Figure 5)

NB 90% pulse duration 280ms (see above)

Yes (see Figure 5)

Figure 5)



Map showing modelled sound

pressure levels (rms*), peak-peak

and sound exposure level (µPa2s)

for the survey area and

surroundings (to levels likely to

affect marine mammals or nearest

land)

* rms calculated by the 90% energy approach for derivation of the duration (Malme et al., 1986; Blackwell et al., 2004).

It is proposed to utilise noise modelling completed in support of the NEG12, NEG13 and NEG14 surveys. This will be supported by additional information from measurements of underwater noise made during the NEG15 survey.

Yes (see example output from the modelling Figure 8).

Provide description of the noise propagation model, including assumptions of sound speed profiles.

The noise propagation

modelling used, is Bellhop and RAM. Bellhop is a geometric beam implementation, and is mostly used for medium- to-deep waters. It supports range-dependent parameters, herein seabed reflection, bathymetry, surface reflection, sound speed profile, volume attenuation. All these parameters are extracted from the databases WOA09, GEBCO, CRUST, each providing precise data for the area in and around the seismic survey zone.

RAM is a parabolic equation (PE) model and is mostly used for shallow waters. It supports the same parameter inputs as Bellhop, as well as complex seabed interaction in cases where layered bottom profiles occur.



D. Specifications of PAM system


Number of hydrophones 4 on array

Yes

Threshold of the recording system –201 dBV re 1 uPa based on

soundcard and NI card

Yes

Sample rate of the recording system Up to 500 KS/s on NI card, 96 KS/s on audio interface

Yes

Where will hydrophones be placed? Approximately 200 metres astern of vessel in close proximity to source array

Yes

Will there be duty cycling of

recordings?

Recordings will be made when suspected sightings are made or as per client request

Yes

In that case when will the PAM system be used?

PAM system used in accordance with local guidelines i.e. 60 minutes prior to ramp up at start of line during darkness or periods of poor visibility.

Yes

Name of software PAMGuard Yes

Species covered Broadband hydrophones covering all species will be covered (0 to 150 KHz response)

Yes

Estimated range accuracy, m. This is dependent on many variables, i.e. frequency, directionality of vocalisation and amplitude of original vocalisation. Typically dolphin species 5000m, whale 10000m, porpoise 200m. Range accuracy 5-10%, direction <5 degrees with Port/Starboard ambiguity

Very low frequency and very high frequency vocalisations will have reduced accuracy due to array geometry and rate of change of position respectively.

Yes



APPENDIX 2. MBES EQUIPMENT

Provided under separate cover.



APPENDIX 3. SBP EQUIPMENT




APPENDIX 4. ICE BUOYS


north east greenland 2016 seismic survey -...

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