Appendix F17

Appendix F17

Browse FLNG DeveLopmeNtDraft Environmental Impact Statement

epBC 2013/7079 November 2014

environmental resources management & sinclair Knight merz 2008

torosa south-1 (ts-1) pilot Appraisal well, environmental monitoring programme – Development of methodologies (part 1), report produced for woodside energy Limited, pp. 51

TOROSA SOUTH-1 (TS-1) PILOT APPRAISAL WELL

ENVIRONMENTAL MONITORING PROGRAMME – DEVELOPMENT OF METHODOLOGIES (PART 1)

Rev 3 26 May 2008

The SKM logo trade mark is a registered trade mark of Sinclair Knight Merz Pty Ltd.


ENVIRONMENTAL MONITORING PROGRAMME – DEVELOPMENT OF METHODOLOGIES (PART 1)

Rev 3 26 May 2008

Sinclair Knight Merz 7th Floor, Durack Centre 263 Adelaide Terrace PO Box H615 Perth WA 6001 Australia Tel: +61 8 9268 4400 Fax: +61 8 9268 4488 Web: www.skmconsulting.com COPYRIGHT: The concepts and information contained in this document are the property of Sinclair Knight Merz Pty Ltd. Use or copying of this document in whole or in part without the written permission of Sinclair Knight Merz constitutes an infringement of copyright.

LIMITATION: This report has been prepared on behalf of and for the exclusive use of Sinclair Knight Merz Pty Ltd’s Client, and is subject to and issued in connection with the provisions of the agreement between Sinclair Knight Merz and its Client. Sinclair Knight Merz accepts no liability or responsibility whatsoever for or in respect of any use of or reliance upon this report by any third party.

TOROSA SOUTH-1 (TS-A) PILOT APPRAISAL WELL

Contents 1 Introduction 1

1.1 Project Description 1 1.2 Background 3 1.3 Objectives of the Environmental Monitoring Programme 5

2 Rig footprint (Objective 1) 6 2.1 Monitoring of Direct Impacts 6 2.1.1 Drop camera benthic community assessment 10 2.1.1.1 Generic drop camera operation 10 2.1.2 ROV ecological assessment 14 2.1.3 Drill cuttings leak plume (secondary ‘impact’ zone) 15

3 Drill Mud and Cuttings Disposal (Objective 2) 18 3.1 Introduction/Background 18 3.2 Drill Centre Water Quality Monitoring 18 3.3 Disposal Site Plume Tracking and Model Verification 18 3.3.1 Materials 19 3.3.2 Sampling Design 20 3.3.3 Field Protocol 21 3.3.4 Data Analysis and Reporting 23

4 Wastewater Discharge Monitoring (Objective 3) 24 4.1 Introduction/Background 24 4.2 Materials and Methods 24 4.2.1 Sampling design and Field Protocol 25 4.2.2 Sample handling, preservation and holding times 27 4.3 Data analyses and reporting 29

5 Sub-surface Noise Assessment (Objectives 4 & 6) 31 5.1 Introduction/background 31 5.2 Fixed Point Underwater Sound Logger 31 5.2.1 Materials and Methods 31

6 Artificial Light Assessment (Objective 5) 33 6.1 Introduction/Background 33 6.2 Materials and Methods 33 6.3 Field Survey Activities and Requirements 33 6.3.1.1 Pre Survey Testing 34 6.3.1.2 Light Survey (Rig Location) 34 6.3.1.3 Light Survey (Sandy Islet Location) 35

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6.3.1.4 Light Survey (Transect) 35 6.4 Data analyses and reporting 37

7 Survey Trip Planning Framework 38 7.1 Introduction 38 7.2 Survey Organisational Structure 38 7.3 EMP Planning Framework and Summary Status 39

SINCLAIR KNIGHT MERZ

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List of Figures Figure 1-1 Location of appraisal pilot well Torosa South-1 and drill cuttings disposal ground.

2

Figure 2-1 Torosa South-1 Appraisal Well: Rig Footprint Impact Zones 8

Figure 2-2 TS-1 rig footprint: Drop camera transects for the primary 'impact' and 'reference' zones 11

Figure 2-3 Examples of Photoquadrat Image Quality - Good Quality (A and B) and Poor Quality (C and D) 13

Figure 2-4 TS-1 Secondary 'Impact' Zone: Drop Camera Transects 16

Figure 3-1 Proposed NTU cable set-up 19

Figure 3-2 Sample quadrant elimination process 21

Figure 3-3 Concentrated sampling approach within the identified plume quadrant 21

Figure 4-1 Stage Two Water Sample Collection Design 26

Figure 4-2 Wastewater discharge water sampling design 27

Figure 6-1 Light Assessment data collection plan 36

Figure 7-1 The organisational structure of the ERM survey team 38

List of Tables Table 2-1 Sampling design 12

Table 4-1 Water quality parameters to be analysed from the wastewater discharge 25

Table 4-2 Required containers, preservation techniques and holding times for parameters to be analysed from the wastewater discharge. 28

Table 7-1 EMP Framework and Summary Status 40


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Document history and status Revision Date issued Reviewed by Approved by Date approved Revision type

Rev A 08/04/2008 Mark Westera Mark Westera 10/04/2008 Draft

Rev B 08/04/2008 Craig Read Mark Westera 10/04/2008 Draft

Rev C 08/04/2008 Robin Kennish Mark Westera 10/04/2008 Draft

Rev 1 08/05/2008 Sam Jarvis - 08/05/2008 Client review

Rev 2 15/05/2008 Sam Jarvis - 15/05/2008 Final client review

Rev 3 26/05/2008 Sam Jarvis 26/05/2008 Final

Distribution of copies Revision Copy no Quantity Issued to

Rev A 1 Electronic Mark Westera

Rev B 1 Electronic Craig Read

Rev C 1 Electronic Robin Kennish

Rev 0 1 Electronic Sam Jarvis (Client Review)

Rev 1 1 Electronic Sam Jarvis



Printed: 26 May 2008

Last saved: 26 May 2008 06:01 PM

File name: I:\WVES\Projects\WV03358\Deliverables\EMP methodology\Rev 3_EMP_Methodologies_260508t.docx

Author: Denise McCorry and Peter Michael

Project manager: Jason Crozier

Name of organisation: Woodside Energy Ltd

Name of project: Torosa South-1 Pilot Appraisal Well

Name of document: ENVIRONMENTAL MONITORING PROGRAMME – DEVELOPMENT OF METHODOLOGIES (PART 1)

Document version: Rev 3

Project number: WV03358-220


1 Introduction Woodside Energy Ltd (hereafter referred to as Woodside) will drill one pilot appraisal well ‘Torosa South-1’ (TS-1), located on the northern edge of South Scott Reef lagoon in April 2008 (Figure 1-1). The drill location is within the Commonwealth waters of Scott Reef which is situated in the Browse Basin offshore of northern Western Australia, approximately 430 kilometres north of Broome. A precision location for TS-A has been selected in order to secure a method to obtain critical sub-surface data and assist with informing the need for, and location of, further appraisal wells that may be required(1).

All activities associated with TS-1 will be managed in accordance with the Torosa South-1 Pilot Appraisal Well Environment Plan (EP) that has been approved by the Department of Industry and Resources (DoIR). The EP details how commitments made in the EPBC Act referral and Supplementary Documentation will be implemented.

In addition to the EP, a comprehensive Environmental Monitoring Plan (EMP) will be developed and executed in the field. There are two objectives of the EMP, which are to:

• Evaluate the appropriateness of mitigation and management commitments made to minimize identified potential impacts associated with the appraisal drilling programme; and

• Obtain data for future environmental impact assessments to be undertaken for the Browse development.

1.1 Project Description Woodside will use the Wilcraft jack-up rig to drill the TS-1 well. The well is located on the northern edge of the southern lagoon of Scott Reef (Figure 1-1) and will take approximately 65 days to drill and profile. Drilling commenced in April 2008, with the objective of completing activities in June 2008.

All drill cuttings and fluids from the TS-1 drilling operations will be recovered to the rig and transported via a vessel to be discharged at a deepwater location 12 km from Scott Reef. This will require two vessels to transport the cuttings.

The jack-up rig, which will accommodate up to 100 people, will be supported by two oilfield support vessels. In total three oilfield support vessels will be used to ship the cuttings and provide support for the rig.

(1) Woodside 2008. Torosa South-1Pilot Appraisal well. EPBC Act Referral.

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Figure 1-1 Location of appraisal pilot well Torosa South-1 and drill cuttings disposal ground.


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1.2 Background The Woodside EPBC Act Referral and Supplementary Documentation(2) (Woodside 2008) identified potential environmental effects from the activities associated with rig deployment, well drilling, profiling and operation of vessels and these were as follows:

Physical disturbance to coral assemblages from the jack-up legs (spud cans), well infrastructure and installation of cuttings recovery equipment;

Impacts on benthic habitat and water quality from disposal of drill muds and cuttings outside of the Scott Reef area;

Potential impacts to water quality and coral assemblages from routine marine discharges such as sewage, bilge water, deck drainage, cooling water, desalination water and waste materials;

Vessels and rig providing a vector for the introduction of non-indigenous marine species;

Noise impacts from the rig, vessels and helicopter when undertaking vertical seismic profiling;

Light impact on fauna;

Emissions to atmosphere from operating equipment;

Accidental hydrocarbon spills during drilling activities;

Potential impacts to water quality, coral assemblages and benthic habitats from rig damage during a cyclone event; and

Interaction with fisheries, shipping and research and monitoring activities.

The activities associated with the appraisal drilling have been assessed through a comprehensive impact assessment process using the Woodside Corporate Risk Assessment tool. Full details are provided in the Woodside Referral Supplementary Documentation. None of the potential impacts identified were associated with a severe risk level. The majority of potential impacts were assigned a low or medium risk level. Only one potential impact was identified as having a high potential risk impact level as follows:

Physical disturbance to coral assemblages from the jack-up legs, well infrastructure and installation of cuttings recovery equipment.

The impact assessment for the rig footprint concluded that damage to the benthic habitats (coral assemblages) would be insignificant and not result in any significant population level effects or impacts on the functioning of the ecosystem and a number of reasons were presented:

(2) Woodside 2008. EPBC Act Referral: Torosa South-1 Pilot Appraisal Well.


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A relatively low proportion of habitat would be impacted (calculated as <0.0005% of the deepwater coral assemblage of Scott Reef southern lagoon) from the direct impact of drilling the well;

The identification of the specific location of TS-1 in an area of low biodiversity that includes the avoidance of corals based on bathymetry and surveys conducted in the proposed site area;

The rig type which is a jack-up rig that does not require anchoring and has limited direct contact with the seabed by the three legs/spud cans, further reducing the footprint impact zone; and

Significant mitigation measures such as to not discharge drill cuttings at the Scott Reef location but to skip and ship to a deep water disposal site, use of low toxicity drill fluids and a riserless mud recovery system to collect drill cuttings and muds from the top hold section and no anchoring (except under circumstances where safety is compromised).




1.3 Objectives of the Environmental Monitoring Programme The Environmental Monitoring Programme (EMP) comprises targeted monitoring activities to assess six key potential impacts identified as part of the proponent’s commitments documented in the EPBC Act referral study(3). The results of the EMP will be used to evaluate and where appropriate verify the commitments made by Woodside to minimize potential impacts resulting from the drilling activities. Furthermore, results of the EMP will be used in modelling verification of predicted plume dispersions for wastewater discharge and drill cuttings disposal and the production of predictive modelling for noise and light impacts for future impact assessment studies relating to the full drilling programme proposed for Southern Scott Reef.

The EMP consists of six key objectives to verify minimal disturbance to the sensitive reefal environment of Southern Scott Reef relating to the activities of the appraisal drilling at Torosa South-1 and these are:

Objective 1 – Rig Footprint: Verify minimal disturbance to the benthic habitat and smothering of benthic fauna.

Objective 2 – Drill Mud and Cuttings Disposal: Monitor potential localised reduction in water quality, smothering of benthic fauna and decreased light attenuation due to increased turbidity at the drill centre and modelled predictions of plume dispersions at the drill centre and disposal site.

Objective 3 – Wastewater Discharge: Monitor potential localised reduction in water quality from discharge of sewage, greywater, bilge, deck drainage, cooling and desalinisation water modelled predictions of discharge plume dispersion at the drill centre.

Objective 4 – Noise: Complete an assessment of underwater noise levels associated with the different phases of the appraisal drilling programme.

Objective 5 – Artificial light: Assess the above-surface light levels and potential impacts on sensitive marine fauna at Scott Reef.

Objective 6 – Vertical Seismic Profiling (VSP): VSP noise level assessment and potential impacts on sensitive marine fauna at Scott Reef.

The EMP will be jointly managed and conducted by SKM and ERM with specialist subcontractors used for specific objectives. Qualified and experienced marine scientific staff from both SKM and ERM are responsible for the development of the monitoring methodologies to address each objective. This report contains the proposed methodologies for each of the six key objectives and these are presented in the following five report sections (Sections 2-6) and Section 7 outlines the proposed survey organization and presents a summary framework for the EMP.

(3) Woodside (2008). EPBC Act Referral: Torosa South-1 Pilot Appraisal Well.


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2 Rig Footprint (Objective 1) Woodside has made the commitment to minimize disturbance to benthic habitat and smothering of benthic fauna that could potentially arise as a result of the TS-1 drilling rig footprint. To ensure that appropriate mitigation and management measures have been put in place and to evaluate their effectiveness a dedicated monitoring programme will be conducted to assess the rig footprint.

The Rig Footprint monitoring programme will address two key issues:

1. Direct impacts of the drilling rig and associated infrastructure and drilling activities to the surrounding seabed. Hereafter, referred to as the primary (rig) ‘impact’ zone; and

2. Potential secondary impacts resulting from the impacts of a drill cuttings leakage scenario on sensitive benthic community receivers, i.e., corals. Hereafter, referred to as the secondary ‘impact’ zone.

2.1 Monitoring of Direct Impacts The direct impacts of the rig and drilling operations at the Torosa South-1 location will be assessed with the employment of two monitoring methods. The first consists of taking a photographic record of the seabed before and after the rig placement and drilling operations. A pre-defined number of towed video/drop camera transects will be surveyed to take a comprehensive suite of photographic images of the primary ‘impact’ zone (the area in which the rig will be in contact with the seabed). The second will address visual impacts directly underneath the rig during the drilling operations and consist of a standardized protocol for the deployment of an ROV within the rig footprint. ROV video footage will be assessed in ‘real time’ to verify that drilling operations are causing minimal smothering of benthic fauna.





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Figure 2-1 Torosa South-1 Appraisal Well: Rig Footprint Impact Zones

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2.1.1 Drop camera benthic community assessment A standardized field methodology for assessment of deepwater benthic assemblages will be employed to make permanent photographic records of the seabed along pre-defined transects. A drop camera system will be used and deployed from a survey vessel before and after the drilling operations.

2.1.1.1 Generic drop camera operation Materials and Methods

The drop camera survey equipment is to be supplied by a subcontractor (Raytech Ltd) to Fugro Pty Ltd for the baseline (before) survey. Fugro Pty Ltd. has been hired by Woodside to conduct geophysical surveys in the Browse development area and will undertake the towed video/drop camera surveys in late March/early April 2008.

The drop camera equipment consists of the following:

A camera frame and simple stabilising vane.

One camera attached to the towed frame providing live video feed and still camera operating modes.

The still camera mode operates with a pair of synchronous strobes.

The still camera mode has a 1.5 mega-pixel image resolution.

Surface viewing of the live video footage is used to guide the position and height of the frame above the seabed. Each photographic image can be framed using the live video image. The video footage can be recorded but only in Hi8 format.

Photographic images are captured in RAW format and converted to JPEG format.

Each photographic image will be geo-referenced with depth information by the combination of the DP vessel and USBL positioning capacity of the towed frame.

Woodside will process all JPEG images into their ArcGIS system for photographic archiving.

Please note that the drop camera survey equipment (as listed above) was used for the baseline surveys and supplied by Raytech Ltd to Fugro Pty Ltd. Fugro Pty Ltd. undertook the drop camera surveys as part of the WEL commissioned geophysical surveys in the Browse development area in March and April 2008.

Sampling design

The sampling design comprises a primary ‘impact’ zone and a matching primary ‘reference’ zone. These zones comprise a circular footprint, 100 m in radius, to capture the area in which a portion



will be occupied by the rig once orientated and positioned at the drill centre. The reference zone has been positioned at a sufficient distance away and upstream of the drill centre so that the likelihood of project impacts is extremely remote. Furthermore, the seabed consists of similar bathymetry and biological features to the impact zone. Pre-defined transects traversing the two primary zones orientated by the primary and secondary compass bearings, i.e., north-south, west-east (transects 1, 3, 5 and 6), northeast-southwest (transect 2) and northwest-southeast (transect 4) will be photographed at 10 m intervals. However, for future surveys replication will be increased to one photograph every 5 m to increase statistical power. It is noted that transects 2-4 of the primary ‘impact’ zone are extended to include seabed areas within the secondary ‘impact’ zone (refer to Section 2.1.4). Each transect (approximately 200-400 m long) will consist of a maximum of 40 photographic images (Figure 2-2 and Table 2-1).

Figure 2-2 TS-1 rig footprint: Drop camera transects for the primary 'impact' and 'reference' zones


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TOROSA SOUTH-A (TS-A) PILOT APPRAISAL WELL

Table 2-1 Sampling design Site BEFORE (baseline) AFTER (post-

decommissioning) RIG IMPACT ZONE Towed video/drop camera x4

transects (1-4) Towed video/drop camera x4 transects (1-4)

RIG REFERENCE ZONE Towed video/drop camera x2 transects (5-6)

Towed video/drop camera x2 transects (5-6)

Image interpretation and data analyses

The drop camera survey mode allows for a series of close-up still images to be taken of the seabed and of the associated sessile benthos. This permits the examination of benthic community composition and characteristics. Differentiation of live and dead benthos can be made from the images and assessed for the ‘before’ and ‘after’ images. ERM staff (including a coral specialist) will be responsible for data extraction from the photographic images after receipt of the images in jpeg and ArcGIS formats.

Estimated cover of biotic and abiotic parameters will be recorded for each seabed image and used to compile a ‘before’ and ‘after’ profile of the primary ‘impact’ and ‘reference’ zones. Where corals are present, details of coral species, growth form and condition (damage / partial mortality / sediment cover / disease), will be assessed. Comparative analyses of the ‘before’ and ‘after’ datasets will be made to assess potential change in the benthic community condition and composition as a result of the rig footprint and drilling activities. Statistical analyses will be employed to address the a priori assumptions of a before-after control-impact (BACI) survey design and hypothesis testing. For example, univariate parameters such as percent live cover and community richness of sessile benthos will be analyses for pre-and post- differences using a nested Analysis of Variance and possible changes in species composition and/or functional groups.

Field protocol

Guidelines for the towed video/drop camera survey were provided to the geophysical survey team. These guidelines were developed in conjunction with Woodside after consultation on the devised field protocol before survey mobilization.

Before commencement of the survey work a hazards register will be compiled and reviewed.

Drop camera transects will be conducted in daylight hours (0700-1800 hrs or 1 hr before sunset)

The drop camera will be lowered at a set point (before the survey transect start) and slowly towed (<2 knots) along a pre-set transect course for a known distance (~400 m).




A series of photographic images (photoquadrats) will be recorded at ten/five metre intervals along the entire length of each transect with the camera maintained at a standardised 1 m height above the seabed.

The USBL positioning equipment will be synchronized with the camera clock so that all images can be geo-referenced in the post-survey processing carried out onshore.

At the end of each transect the drop camera frame will be retrieved and photo images downloaded to a back-up storage device after reviewing the image quality and confirming acceptability. The key image quality indicators are for the images not to be blurred (this is typically a result of the drop camera towing speed) or of insufficient detail (due to the images being taken too far away, from an extended height). Refer to Figure 2-3.

A trial run to test the equipment and survey logistics will be conducted on transects 5 and 6 of the primary ‘reference’ zone.

A field log of the survey work completed will be kept and include information on the date and time of each survey transect recording, start and stop time, success of obtaining good quality images, general sea conditions and operational challenges, if experienced.

A C

B D

Figure 2-3 Examples of Photoquadrat Image Quality - Good Quality (A and B) and Poor Quality (C and D)




2.1.2 ROV ecological assessment The drilling rig will be equipped with an ROV which will be routinely deployed to inspect the well area and operating equipment. During the drilling operations the rig footprint monitoring will employ the ROV to conduct ecological survey checks of the seabed and benthic communities underlying the rig. These surveys will comprise a series of visual checks carried out by the ROV operator and recorded footage of the seabed surrounding the three spud cans and in close proximity to the well area, an area estimated to be approximately 500 m2. The surveys will be used to assess potential sediment accumulation and the health status (living or dead) of any existing epibenthic fauna underlying the rig.

It is recommended that the ROV ecological surveys are conducted at the following times:

As soon as possible, following the placement of the rig infrastructure on site. This first survey will document the actual seabed disturbance resulting from the placement of the three rig spud cans and other equipment within the well area. It is noted that the well location is comprised of a dense cover of rubble and coral fragments. This rubble and fragment layer lies over a matrix of coarse sand which is not expected to cloud the water column as it has a relatively low silt fraction.

Monthly during the drilling operations until rig decommissioning.

After any reported mud or cuttings spills. It is suggested, though dependent on operational logistics, that an ROV ecological survey check is conducted immediately following such an incident and after a two hour period when sediment deposition from either scenario would have stabilized (as suggested by the modelling(4) ).

To assist the visual inspection of potential sediment accumulation underneath the rig it is recommended that visual markers are used and as discussed these could be one or both of the following:

Deployment of weighted reference marker (traffic control cones) with graduated markings in centimetres at several locations underlying the rig.

Paint graduated markings in centimetres on the upper spud cans and lower rig legs while the rig is dry docked for the necessary alterations needed for the Torosa South –1 drilling programme.

(4) Op. Cit.




Field protocol

The ROV ecological survey check will consist of the ROV recording video footage from around each of the three spud cans and the well area (RMR system). Each spud can will be designated a number 1-3 and each visited in a consistent order throughout the surveys.

Checklist for the ROV operator:

Date, time and tide noted in a standardized operational recording log.

ROV video footage taken around each spud can and around the well area in a consistent order: Well area, spud can 1-3.

If markings are placed on the spud cans/legs of the rig close up recordings of these will be taken and the height of sediment noted for each.

Alternatively or in addition, if markers are placed within the rig area close up footage of these will be taken and the height of the sediment noted for each.

The general condition of living epibenthos around each area of rig infrastructure will be noted: sponges, soft corals, hard corals, algae. A photographic guide to be supplied with guiding notes.

General status of the seabed and any observations of introduced sediment covering noted.

A recording sheet and suggested layout of the ROV recording route to log all the above activities and observations. An induction session will be conducted with all ROV operators.

ROV footage and log sheets will be transferred to the Woodside Perth office on a regular basis and footage sent to ERM for assessment.

2.1.3 Drill cuttings leak plume (secondary ‘impact’ zone) A series of drop camera transects traversing an area identified as the secondary ‘impact’ zone before and after the rig deployment and drilling operations will be surveyed (Figure 2-4. transects 7-10). The secondary ‘impact’ zone encompasses the predicted area of a drill cuttings leak plume. This is the potential impact zone of a drill cuttings plume in the event of a recovery pump or hose failure. Again, similar to the primary ‘impact’ zone this is matched with a series of ‘reference’ transects (Figure 2-4 transects 11-16). Transects have been pre-defined to ensure the photographic images capture data from the raised seabed features (as visible from the bathymetry overlay). The bathymetry and previous survey work confirmed the presence of coral bommies (and hence sensitive receivers) in the vicinity of a predicted sediment plume should the situation arise where a failed recovery hose scenario occur (Figure 2-4 transects 7-16).

Data collection and analyses will be conducted as outlined in Section 2.1.1.




Figure 2-4 TS-1 Secondary 'Impact' Zone: Drop Camera Transects




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3 Drill Mud and Cuttings Disposal (Objective 2) 3.1 Introduction/Background A dedicated monitoring programme (a component of the EMP survey trip) will be conducted to verify the modelling results of the drill mud and cuttings disposal and determine any actual impacts to Scott Reef. A number of specific actions to minimise localised reduction in water quality, smothering of benthic fauna and decreased light attenuation due to increased turbidity have been outlined in the Woodside referral study document and will be implemented as part of the Environmental Plan for the Torosa South-1 appraisal well drilling campaign. These include the use of water-based drilling muds, recovery of all drill muds and cuttings, and their disposal at a suitably identified deepwater site 12 km away from Scott Reef.

The monitoring programme consists of tracking the cuttings plume over several dumping events at the disposal site and the deployment of a multi-probe sensor in the vicinity of the well area.

3.2 Drill Centre Water Quality Monitoring Woodside has deployed a series of multi-probe water quality loggers within the Southern Lagoon of Scott Reef. Data from one logger positioned closest to the Torosa South-1 well area (PE_7) will be obtained to test whether drilling activities impact localised water quality and light attenuation. Woodside have deployed a multi-probe seabed logger - SEABIRD SBE 16 Temperature and Salinity logger with integrated Wetlabs ECO FLNTU chlorophyll and turbidity sensors and ECO PAR sensor. The parameters recorded at preset time intervals are: temperature, conductivity, turbidity, Chlorophyll a, Photosynthetically Active Radiation (PAR) and sediment deposition.

The logger was deployed within Southern Scott Reef between 25-27th March at a site in 44 m depth and southwest of the Torosa South-A drill centre. Since deployment background data within the lagoon are currently being recorded and data are downloaded bimonthly. Woodside are currently considering the re-positioning of this logger to a location within the predicted area of failed cuttings hose dispersion plume at the Torosa South-1 drill site.

3.3 Disposal Site Plume Tracking and Model Verification In-situ water quality monitoring in the vicinity of the designated disposal site is required immediately following the disposal of drill mud and cuttings. The primary aim of the monitoring and sampling regime is to describe the cuttings plume behaviour (temporal and spatial patterns of dispersion) and verify the modelled predictions of the associated turbidity plume dispersion.

Field sampling has been proposed for the period between 4th and 8th June 2008. Advice from the modeller (GEMS) is that sampling should coincide with neap tide or turn of the tide when plume dispersal is predicted to be reduced compared with a spring tide. This is yet to be verified. In-situ measurements of Nephelometric Turbidity Units (NTU) will be collected in the waters immediately




adjacent to the disposal site using a towed cable fitted with NTU loggers to develop a turbidity profile throughout the water column. Samples of the drill cuttings will be collected and supplied to In Situ Marine Optics (IMO) to establish a site specific relationship between NTU and Total Suspended Solids (TSS) under laboratory conditions. Results of this relationship will be applied to NTU measures recorded in the plume to determine the relative TSS measures. Samples of the material to be disposed will be taken from each of the dumping events monitored to establish a particle size distribution (PSD) of the material.

3.3.1 Materials The equipment required to monitor potential localised reductions in water quality and verify the modelled plume dispersion predictions consists of the following:

Vessel

Boat equipment (winch, differential GPS tracking and plotting system and Laptop/rugged reader)

Personnel x 2

Equipment for turbidity plume tracking and monitoring

An ‘NTU tow cable’ will be set-up, consisting of five NTU loggers spaced 5 m apart so readings can potentially be obtained above, within, and below the turbidity plume at any given time (Figure 3-1).

Figure 3-1 Proposed NTU cable set-up

Sea Surface

Tow Cable Weight

NTU Logger

25 m

Turbidity Plume

Survey vessel

The NTU instruments deployed will be the TPS WP88T which are capable of logging NTU data while providing ‘real-time’ readings to rugged readers aboard the vessel via communication cables.




The communication cables will be bound together at the determined staggered depths on a double braid spine rope. The spine rope will provide extra strength and support when retrieving the array.

The cable will be weighted as needed below the deepest logger so that it will hang vertical in the water column for geo-referencing accuracy.

The array and the communications cables will be designed so that they can be lowered to a maximum depth of 50 m should this be necessary to remain within the plume.

A Level Troll 500 logging depth sensor will be attached to the top and bottom nephelometers in the array and to log the depth at which the array is travelling through the plume.

Equipment for disposed material sampling

Storage as necessary for drill cutting samples (9 x 9 litre buckets with lids and refrigeration).

3.3.2 Sampling Design It is proposed that the plume from at least three dumping events are tracked and monitored to increase the accuracy of the methodology and account for any variation in data which is likely to occur.

Turbidity plume tracking and monitoring The sampling design primarily involves locating the boundary of the plume, as it is anticipated that the turbidity plume dispersed from the disposal of material will not be visible from the surface and is likely to dissipate rapidly. As indicated by the GEMS model predictions, the general direction of the plume can be determined by the tidal movement and prevailing weather conditions at the time of dispersal. Prior to commencement of sampling, a visual check of the surface water for any indication of the plume will be carried out in order to determine its direction of movement, however if the extent of the plume is not clearly visually evident, using knowledge of the predicted plume behaviour (prior consultation with GEMS modeller), the general location of the plume can be identified through a process of quadrant elimination as depicted in Figure 3-2. The study area for this process of elimination will encompass the predicted coverage of the plume and will be divided into four appropriately sized quadrants (approximately 50 m x 50 m is sufficient), each radiating from the disposal point. The collection of data will begin as close (minimum distance of 25 m from the disposal point is suggested for safety reasons), and as soon as practicable to the disposal point and continue on an outward spiral away from the disposal point at pre-determined distances apart, eliminating quadrants without significantly elevated NTU relative to background levels.






KEY

Figure 3-2 Sample quadrant elimination process

Given the expected absence of other factors that can cause small scale patches of elevated NTU (e.g. phytoplankton blooms, organic matter etc), the quadrant with elevated NTU will be assumed to indicate the likely presence of the turbidity plume. Once the quadrant containing the plume is identified, a more concentrated sampling pattern will be initiated to provide information on the spatial extent of the plume. In this approach, parallel transects of data acquisition will be carried out to further define the extent and concentration of the plume (Figure 3-3).

\

Figure 3-3 Concentrated sampling approach within the identified plume quadrant

3.3.3 Field Protocol Turbidity plume tracking and monitoring

The following guidelines for the plume tracking and monitoring survey will be provided to the water quality monitoring team prior to the commencement of the survey. It is recommended that this procedure is carried out for at least three dumping events.

Plume

Disposal site

Quadrant boundary

Study area

KEY

50 m

Survey route

Plume

Disposal site Survey route

Quadrant boundary

Study area

NTU not elevated

Elevated NTU 100 m


Before commencement of the survey, a hazards register will be compiled and reviewed.

Disposal events should be timed to coincide with neap and slack tides. Tidal direction and weather conditions shall also be noted along with a visual check of the surface water prior to commencement of the dumping to determine the predicted direction of the turbidity plume (and hence which quadrant to focus the survey on). Time series on the vessel’s DGPS tracker and the NTU loggers will be synchronized in order to determine the exact location of the logger/vessel when the plume is located and throughout the plume tracking exercise and measurements of elevated NTU.

The survey will begin as soon and as close as practicable to the dumping activity, as it is expected that the suspended solids will dissipate rapidly into the water column.

Monitoring will focus on the top 25m of the water column as this is the area where finer particles are likely to remain and disperse horizontally for considerable distances before finally settling. However the nephelometer array will be capable of being deployed to a depth of 50m if necessary (and achievable under the prevailing conditions).

All the NTU loggers along the array will be set to record and log data continuously at 5 second intervals, with wiping of the sensor occurring every minute. The loggers used have the capacity to store 2400 data points, equating to 200 minutes of data acquisition based on one reading every 5 seconds. Loggers will be downloaded and data backed up after each sampling event to ensure there is sufficient logging memory available for each of the surveys.

The NTU logger cable will be lowered at a set point and slowly towed (< 2 knots) along a pre-determined transect (i.e. Figure 3-2 and Figure 3-3) for a known distance and duration. If determined from trial runs that the array doesn’t hang as vertically as desired in the water column while towing, a formulae will be devised to calculate the depth and position of the array based on boat speed, current speed and direction, and GPS.

Spikes in NTU values can be used to indicate the presence of a turbidity plume arising from the dumping. The log time of areas with such values will be later matched with the location of the vessel at that time for geo-referencing purposes. The geo-referenced position of elevated turbidity readings will be later used for model verification.

A field log of the survey work will be kept, including all required information for quality assurance and quality control (QA/QC) purposes.




Disposed material sampling

Representative samples of the material to be disposed will be collected prior to each of the dumping events monitored. Samples are required to determine particle size distribution (PSD) and to establish the site specific relationship between NTU and TSS. Three 10L sample buckets will be filled with cutting material (~ 8kg each) by rig personnel prior to each of the dumping events. A total of 9 samples will be collected for analysis of PSD and NTU / TSS relationships over the EMP survey period (three dumping events).

Sample Handling, Preservation and Processing

Sampled cutting material will be placed into 10 litre buckets with water tight lids and held on vessel with no additional holding requirements. Once on-shore, the samples will be transferred to In Situ Marine Optics (for NTU/TSS assessment).

3.3.4 Data Analysis and Reporting TSS and NTU relationship

A relationship between the NTU determined from in-situ measurements (from nephelometer) and TSS will be established by In Situ Marine Optics for model validation, as the plume parameter modelled is TSS.

Plume model verification

Once a site specific NTU/TSS relationship has been determined, the tracked NTU plume can be converted to relative TSS and verified against the model in terms of TSS concentration, extent of the plume coverage and direction of movement. Access and time with the TS-A GEMSS models and the modelling team will be needed for the verification work.




4 Wastewater Discharge Monitoring (Objective 3)

4.1 Introduction/Background Sewage and grey-water, bilge water, deck drainage water, cooling and desalinisation water discharge will be controlled through a comprehensive set of actions under the Torosa South-1 EP. This includes using a MARPOL approved sewage treatment processes, an oil-in-water separator for bilge water and bunding of hydrocarbons and chemicals to prevent residues/spills from entering the overboard drainage system. The environmental objective for routine discharges is to minimise: potential acute toxicity effects on corals, other benthic organisms or water quality; and indirect effects to marine fauna both in the water column and on the seabed.

An evaluation of the environmental objective for wastewater discharge, verification of the discharge water modelling and determination of actual impacts to the marine organisms of Scott Reef will be undertaken as part of the EMP. The content of the wastewater discharge will be examined at the point of discharge on the rig to evaluate the load profile and compare this to the predicted water discharge quality assessment (5). Furthermore, a targeted water sampling survey will be undertaken on site during the drilling rig operations to confirm the vertical and horizontal dilution of the wastewater discharge plume.

4.2 Materials and Methods A two stage approach to monitoring the discharge waters from the drilling rig is proposed.

Stage One will involve the evaluation of the load profile of the discharge waters over a 24 hour period and an examination of the temporal patterns of discharge volumes from the operational records over the period of sampling. Water samples will be collected at six hourly intervals from two sources: A. treated sewage and B. excess seawater discharge points. Further details of the daily patterns of discharge volumes released will be requested from WEL. The stage one sampling will be conducted by rig personnel under the supervision of a WEL representative.

Stage Two will consist of a dedicated water quality sampling programme at the time of the EMP survey trip. Water sampling and temperature/salinity profiling will be conducted within the discharge plume at the point of entry into the surface waters and at pre-defined stations away from the rig. The distance and depth gradients for the sampling stations have been determined by the GEMS 3D Plume Dispersion Model (PLUME3D) and will focus water sampling within the top ten metres of the water column so as to maximise detection of the discharge waters in the vertical dilution profile.

(5) Woodside 2008. EPBC Act Referral: Torosa South-1 Pilot Appraisal Well.




4.2.1 Sampling design and Field Protocol

Stage one sampling – Discharge load profile

Water samples will be taken of the wastewater on the rig before the point of discharge every six hours over a 24hr period to account for all potential periods of high waste output. Samples will be taken from two wastewater sources; the sewage discharge, and the excess seawater. Temperature, pH and salinity will be measured at the time of sampling for each sampling interval using a hand held TPS WP81 probe. The water samples will be handled and stored as outlined in Section 4.2.2 and analysed for the parameters listed below in Table 4-1.

Table 4-1 Water quality parameters to be analysed from the wastewater discharge

Water quality parameter pH Salinity (ppm) Temperature (ºC) Total Nitrogen (mg/L) Total Phosphorus (mg/L) Oil (mg/L) Aluminium (mg/L) Boron (mg/L) Barium (mg/L) Beryllium (mg/L) Cadmium (mg/L) Chromium (mg/L) Copper (mg/L) Manganese (mg/L) Nickel (mg/L) Strontium (mg/L) Zinc (mg/L) Arsenic (mg/L) Lead (mg/L) Mercury (mg/L)

Results will be analysed by ERM staff to compare the load profile with the predicted water discharge quality assessment and to determine temporal variation in water quality parameters and determine the optimal times for sampling of surrounding seawater around the rig.




Stage two sampling – Wastewater discharge plume

A tentative sampling design is proposed here and consists of sampling during the tidal windows of slack water and peak flow (representing the range of potential dispersion of the discharge waters). These tidal states will be determined for the dates of sampling and the predicted direction of the discharge plume as determined by tide and currents identified (to be requested from oceanographic consultants, GEMS). The sampling design will comprise of four water sampling stations (Figure 4-1): 50 m, 100 m, 200 m and 300 m distance away from the source point within the predicted dispersion of the discharge plume. At each station, replicate two litre water samples will be collected at depths of 1 m, 3 m, 5 m, 10 m and 15 m using a 5L teflon ‘Niskin’ bottle. Appropriate volumes of each of the replicate water samples will be bottled into designated sample containers as outlined in Table 4-2.

At each of the sampling stations, a vertical temperature/salinity profile through the water column will be determined using a TPS WP84 temperature/salinity profiler. Data obtained will be manually logged on the instrument at 0.5m increments to a depth of 10 m and then every 1 m to a depth of 20 m. Data logged on the instrument will be downloaded to a PC following each sampling event. The location of the collected water samples and the temperature/salinity profiles will be recorded using the vessels DGPS.

Figure 4-1 Stage Two Water Sample Collection Design

300 m 200 m 100 m 50 m

X X X X X X X X

X XX X X X X XX XX X X X X X

20 m

X X X X X X X X

X X X X X X X X

KEY X Water sample Discharge point Temp/salinity profile




Two water quality surveys shall be conducted for each of the specified tidal states with an interval of 24-48 hours between sampling. For one sampling period (a single tidal state) 40 water samples will be collected, totalling 160 water samples from within the discharge plume over the EMP survey period (Figure 4-2). It is strongly recommended that a further set of water samples should be taken from a reference site at an upstream location in proximity to the drilling rig at both a slack and peak tidal state. Three 2L replicate samples will be taken from a depth of 5 m during each tidal state, resulting in a further 6 water samples being collected for this reference analysis (Figure 4-2).

Figure 4-2 Wastewater discharge water sampling design

A minimum of 220 L and 8.25 L need to be collected from the discharge and reference sites respectively to account for the volume required for analysis of the parameters as outlined in Table 4-2. This volume will be easily catered for, as 160 and 6 samples at 2L each far exceeds this requirement. The excess volume collected is to ensure all required sample containers can be filled from the one sample while still accounting for small spills and leakages which are likely to occur. Excess water samples may also be used as field splits for QA/QC purposes where deemed necessary. A minimum of 3 samples from known stations and depths on each sampling occasion (both discharge and reference sampling) will be split for analysis of the same parameters by a second laboratory for quality assurance purposes. Fifty percent of these split samples will be sent as ‘blanks’. SKM will ensure that the analytical protocols followed by the laboratories are mirrored, allowing comparison between results obtained.

The water samples will be handled and stored as outlined in Section 4.2.2 and analysed for the same parameters as outlined in Table 4-1.

4.2.2 Sample handling, preservation and holding times Water samples are susceptible to change as a result of physical, chemical or biological reactions which may occur between the time of field sample collection and subsequent laboratory analysis.




The extent of change in properties of the water samples will be affected by post-sampling processing and handling parameters such as the storage temperature, exposure to UV light, the nature of the water sample container used and the time between sampling and laboratory analysis. Table 4-2 outlines the recommended water sample containers, preservation requirements and holding times for analysis of the desired parameters.

Table 4-2 Required containers, preservation techniques and holding times for parameters to be analysed from the wastewater discharge.

Parameter Analytical Laboratory

Storage container / minimum volume

Filling technique Preservative Maximum holding time

Oil and Grease

ALS 1 x 1000mL Amber glass bottle

Fill the bottle to the neck.

Pretreated sulphuric acid bottles. Refrigerate/Ice

(4°C) for the holding period 28 days

Total Nitrogen (TN)

ALS 1 x 250mL plastic bottle

Fill below the neck (~90% full).

Pretreated sulphuric acid bottles. Refrigerate/Ice

(4°C) for the holding period 28 days

Total Phosphorus (TP)

Dissolved heavy metals

ALS 1 x 125mL plastic bottle

Filter sample through 0.45µm filter membrane.

Refrigerate/Ice (4°C) for the holding period

6 months

To avoid potential contamination of the water to be analysed for metal elements, the following points shall be adhered to during the water sampling and bottling process:

Samples should be obtained using a Teflon-coated Niskin water sampling bottle.

Between samples (including replicate/duplicate samples) all equipment (i.e. Niskin bottle & funnel) shall be washed in a tub of decontamination solution (Decon 90) then rinsed in a tub of fresh water.

Prior to each of the four sampling events, fill four 125ml plastic bottles with filtered non-contaminated reference seawater. Refrigerate (4°C) two samples and leave two at room




temperature for the duration of the trip. Analysis of these standards/blanks will demonstrate whether contamination of samples is occurring during the storage stage.

Prior to each of the four sampling events, also collect a 1L sample of non-contaminated reference seawater. Leave the sample at room temperature aboard the vessel, while filling (filtering) one 125ml plastic bottle at each of the 5 sampling stations and treating as described in Table 4-2 for metals. Analysis of these samples will account for any contamination occurring during the sampling and bottling process.

The water sampling equipment shall be supplied to the analytical laboratory to test with known water sample standards. Variation detected in the results of these known standards will indicate the level of contamination occurring as a result of contact with the sampling equipment.

Sterile latex gloves should be worn at all times when handling water sampling equipment. Gloves should be changed between each water sampling station.

Personnel in contact with the rope and messenger of the Niskin bottle should at no time come in contact with the water sample.

Suncream/zinc and any other potential anthropogenic contaminants shall be avoided by the personnel in contact with the water samples.

Sample container lids shall not come in contact with anything potentially contaminated (i.e. table, vessel).

Any equipment which comes in contact with the vessel and potentially contaminated personnel shall be cleaned in the decontamination solution prior to being used.

4.3 Data analyses and reporting The load profiling data for the wastewater discharge will include analyses of the water quality parameters measured, such as temperature and salinity and their temporal variation over the 24 hour sampling period. These results will be compared to the documented values at discharge, predicted water discharge quality at 100 m (100 dilutions) and ANZECC guideline trigger values. The operational discharge volumes will also be assessed for the same time period and temporal variation of discharge rates and volumes documented. This will be the first stage of verification of the management of wastewater to the standards documented in the referral study and Environmental Plan.

Results of the in-situ water quality monitoring, temperature/salinity profiling and water quality parameters will be analysed and used to show the vertical and horizontal dilution of the wastewater plume in the waters surrounding the drilling rig (if detected). These results will then be compared to the predicted dilutions of the PLUME3D model and to examine actual/potential impacts to




marine organisms within Scott Reef. Access and time with the TS-A GEMS 3D Plume Dispersion Model and the modelling team will be needed for the verification work.




5 Sub-surface Noise Assessment (Objectives 4 & 6)

5.1 Introduction/background The potential disturbance to marine fauna from noise will be assessed as part of the Torosa South-1 EMP. Data will be used to evaluate the environmental objective to minimise potential physiological effects or disruption to behaviour patterns of marine fauna due to sound energy associated with the rig, support vessels and helicopter operations. The EMP will specifically address an assessment of underwater noise levels from the drilling activities of the Torosa South-1 appraisal well and, if data is available, map the expected decay of sound levels with distance from the drilling rig.

The study objective is:

To gain a better understanding of the radiance of underwater noise from the drilling rig (including the activity of support vessels and Vertical Seismic Profiling) specific to the appraisal well drilling at Torosa South-1

A dedicated monitoring programme will be conducted using a single fixed point underwater sound logger to record sound measurements due to the various drilling operations and support vessel activities. This should allow an assessment of the noise levels due to these activities and thus allow a prediction of potential impacts.

5.2 Fixed Point Underwater Sound Logger A series of underwater sound loggers are currently deployed in the southern Scott Reef area by Curtin University and the logger positioned nearest to the drill centre will act as the fixed point underwater sound logger for the Torosa South-1 appraisal well drilling.

5.2.1 Materials and Methods The exact location of the logger needs to be confirmed by Curtin University. The frequency range of interest should cover at a minimum 0.01 – 100 KHz.

Woodside will ensure that the underwater acoustic noise data collected in situ by the sound logger (confirm exact distance from the Torosa South-1 appraisal well drilling operation) will be downloaded and forwarded to SKM staff for appropriate formatting and subsequent analysis. The information to be provided is the time vs frequency vs SPL, and spectra and spectrograms for all events. It will be necessary to have access to time logs showing what activities occurred and when so that they can be correlated with the monitored noise level. In order to be able to definitively attribute noise levels to specific noise sources, the log of activities should include not only the drilling rig activities but also support vessel approach/departure times (engine running condition




when nearby (any bow thruster activity?) and the helicopter over-flight times. Support vessel and helicopter flight/approach and departure tracks should be marked on a map of the reef to show these relative to the fixed noise logger location to allow distances to be estimated.

All the identification work assumes that the noise logger location is not far enough away from the drill rig location that all activities proposed are below the ambient noise level at the logger location. It would be useful for this purpose if a logger could be located in the vicinity of 1 km from the proposed drilling activities.




6 Artificial Light Assessment (Objective 5) 6.1 Introduction/Background The generation of artificial light from marine drilling activities and equipment has the potential to result in light spill and glow, particularly during night-time operations. Lighting on the rigs and support vessels will be used for safe illumination, at levels that provide sufficient safety around work and accommodation areas for personnel. The introduction of artificial light to a marine ecosystem has the potential to affect species such as marine turtles. Light levels should be measured to determine the change in environmental conditions.

Data collated during these surveys can be used for predictive modelling of light emissions from drill rigs at any location within Scott Reef.

6.2 Materials and Methods Light emission data for drilling activities at Scott Reef will be collated over two field surveys; a base line survey of existing conditions (no artificial light), and an operations monitoring survey (artificial light). This will enable a direct comparison of conditions to determine any changes in light wavelength and density. This is expected to provide further detailed information on identifying high risk areas for light emissions.

Field surveys should be undertaken with comparable environmental conditions. The absence of the moon is critical for collating a clear data set that is not influenced by lunar light emissions. Due to logistical constraints, it is necessary to undertake the base line survey of existing conditions after the drilling period; this is not expected to alter the data in any way. As such, the following timing is provided for field surveys:

Drilling operations: 01/05/08 – 09/05/08



Baseline Survey: 29/07/08 – 04/08/08

Baseline Survey: 27/08/08 – 02/09/08

6.3 Field Survey Activities and Requirements The objective of the field survey is to determine light measurements of ambient conditions (at night) using a hand held lux meter, and a hand held spectrometer (this is connected to a small laptop computer). The light will be measured at both Sandy Islet and the Drill Rig, with measurements taken at approximately 1 m above sea level at multiple locations within a grid layout, and a potential linear transect. The grids will be navigated via a pre programmed route within a hand held GPS carried by field staff. An example of data collection areas is demonstrated on Figure 6-1.




A detailed list of activities and requirements will be described for each survey; however the following applies to all surveys:

Data collection to commence at one hour after sunset, with completion within approximately 6 hours.

Data collection vessel to be sufficient in size to enable light measurements at approximately 1 m above sea level (within arms reach), and transfer of two field staff between vessel and Sandy Islet. This vessel is required to have all lights covered (by towel or dark material) during data collection to avoid interference with light instruments. Data will be collected at 100 m increments, where vehicle must be stationary, onboard lights can be exposed during transit between these points.

All marine vessels (other than the light survey vessel) to vacate the light survey area during surveys, this includes the area between the Drill Rig location and Sandy Islet. This is a requirement to avoid interference with light data collection.

Before commencement of the survey work a hazards register will be compiled and reviewed.

6.3.1.1 Pre Survey Testing Prior to commencement of night survey, a ‘dry run’ is required during daylight hours to test equipment and familiarise vessel crew with collection methods and reconnaissance. This is expected to occur between arrival on site, and sunset, dependant on transfer times. A rest period is also required upon arrival on site.

A survey of Sandy Islet is required during daylight hours to map the extents of the Islet with a GPS. This will define light data collection locations.

A survey of the Drill Rig is also required during daylight hours to photograph light fittings, locations and direction. This may be conducted over a period of days, dependant on scheduling requirements.

6.3.1.2 Light Survey (Rig Location) Light emission data will be collated within a grid surrounding the Drill Rig. An example of the grid is demonstrated on Figure 6-1

Data will be collected within 50 m of the Drill rig.

The proposed data collection grid will involve collection points at 100 m intervals surrounding the Drill Rig.

No change is required to Drill Rig lighting at any time during light survey.




6.3.1.3 Light Survey (Sandy Islet Location) Light emission data will be collated within a grid surrounding Sandy Islet. An example of the grid is demonstrated on Figure 6-1

Data will be collected on Sandy Islet. All lights on board the survey vessel must be screened during light data collection on Sandy Islet.

Photographs will be taken of the Drill Rig whilst ashore Sandy Islet.

The proposed data collection grid will involve collection points at 100 m intervals surrounding Sandy Islet.

Photographs of the Drill Rig will be taken during transit to or from Sandy Islet.

6.3.1.4 Light Survey (Transect) If light levels collected within the Drill Rig grid are detected at a 1 km distance from the Drill Rig, data will need to be collected along a transect (as shown on Figure 6-1). This, however, is not expected to occur.

Data will be collected at 100 m intervals along transect.

Proposed Scheduling of Survey

Objective Day Time Tasks

Preparation 01 TBA Transit to Scott Reef Recuperation/Induction Reconnaissance of Drill Rig Survey Area.

Drill Rig Survey 01 8pm – 2am Collect light data via small vessel Sandy Islet Survey 02 Daylight hours

8pm – 2am Recuperation Reconnaissance of Sandy Islet Survey Area. Collect light data via small vessel Inventory of lights and light data collection

On Rig Audit 03 8pm – 2 am

Complete any unfinished data collection (transect).

Contingency 04 8pm – 2am

Demobilise 05 Daylight hours Transit from Scott Reef




Figure 6-1 Light Assessment data collection plan




6.4 Data analyses and reporting Data collected during field surveys will be analysed and reported upon return to Perth. The following outputs are expected:

Report on Drill Rig lighting (includes photographs of luminaires, location and direction). A survey plan of the rig is required prior to departure to field. This includes light locations and specifications.

Report on Base Line conditions at Scott Reef, focussing on the Drill Rig location and Sandy Islet. This will be communicated using lux mapping and wavelength graphs.

Report on Drill Rig Operations, focussing on the Drill Rig location and Sandy Islet. This will be communicated using lux mapping and wavelength graphs.

Photomontage of Drill Rig operating at north east limits of drilling area. Methodology for this output will be included.




7 Survey Trip Planning Framework 7.1 Introduction A dedicated survey trip will be implemented to conduct the majority of the monitoring programmes contained within the EMP. The survey trip will be conducted during the middle of the drilling programme (to be confirmed) and the primary activities will consist of:

Drill muds and cuttings disposal plume tracking;

Wastewater discharge water quality sampling and temperature/salinity profiling; and

Artificial light assessment using portable lux meter and spectrometer.

7.2 Survey Organisational Structure The organisational structure of the ERM survey team is below (Figure 7-1):

Figure 7-1 The organisational structure of the ERM survey team






7.3 EMP Planning Framework and Summary Status A summary table of the EMP framework and summary status is presented here as a guide to the overall scope of the monitoring activities, their timing and duration and follow up required for each of the monitoring components of the EMP (Table 7.1).



Table 7-1 EMP Framework and Summary Status

EMP Objective Monitoring activity Sampling period Status Comments

1. Rig Footprint Drop camera transects Before and After drilling Completed before drilling survey work

Data gap for transects of the secondary reference area will not be photographed before the drilling programme commences.

ROV Routine Ecological Survey Check

During drilling operations on a monthly basis

ROV checks underway Protocol developed and in implementation phase.

2. Drill cuttings disposal Well area water quality

monitoring Before and during drilling operations

Multi-probe loggers installed within Southern Scott Reef

Arrangements for data retrieval bimonthly.

Disposal site cuttings plume tracking

EMP survey trip Preparation phase Duration of fieldwork: 3 days ( Three dumping events)

3. Wastewater discharge 24 hour load profiling EMP survey trip Preparation phase Equipment – handheld temp/salinity probe (TPS WP81), sample

bottles (x72), guidance notes and record log format for rig crew to collect samples, storage and transport logistics, analytical lab arranged.

Wastewater discharge water quality sampling and temp/salinity profiling

EMP survey trip Preparation phase Equipment: Water sampler, temp/salinity probe (TPS WP84).

4. Sub-surface noise assessment

Fixed underwater sound logger

Before and during drilling operations

Curtin University logger deployed in Southern Scott Reef

Arrangements for data retrieval and processing completed.

5. Artificial light assessment Portable lux and spectrometer

recording systems EMP survey trip and baseline survey required post decommissioning

Preparation phase Fieldwork duration = 4 nights

Appendix F17

Documents

Transcript of Appendix F17