TABLE OF CONTENTS 1.1 PURPOSE AND OBJECTIVE SCOPE DESCRIPTION OF THE ACTIVITY AND ENVIRONMENT 12

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Technical#810827 Rev 4 Page 2 of 169

INTEGRATION WITH OTHER PLANS

16

1.4.1 PTTEP AA Plans 16

1.4.2 External Plans 16

2

EMERGENCY RESPONSE ARRANGEMENTS

17

2.1

PTTEP AA CRISIS AND EMERGENCY ORGANISATION

17

2.1.1 Emergency Management Team 17

2.1.2 Crisis Management Team 18

2.1.3 CMT and EMT Support Groups 19

2.2

STATUTORY REQUIREMENTS AND SPILL RESPONSE AUTHORITIES

19

2.2.1 Definition of Tier Levels 19

2.2.2 Statutory Authority and Combat Agency 20

2.2.3 NOPSEMA 21

2.2.4 AMSA 21

2.2.5 Department of Environment 22

2.2.6 State/Territory Authorities 22

2.3

INDUSTRY ARRANGEMENTS

23

2.3.1 Australian Marine Oil Spill Centre (AMOSC) 23

2.3.2 Oil Spill Response Ltd 23

3

INITIAL RESPONSE ACTIONS

24

3.1

REPORTING AND NOTIFICATION

24

3.2

ESCALATION AND DE-ESCALATION OF RESPONSE TIERS

27

3.3

INCIDENT ACTION PLAN

27

4

FATE OF SPILT HYDROCARBONS

29

4.1

SPILL SCENARIOS

29

4.2

HYDROCARBON PROPERTIES

29

4.3

ZONE OF POTENTIAL IMPACT

30

4.4

PRIORITIES

35

5

SPILL RESPONSE STRATEGY

36

5.1

OVERVIEW OF RESPONSE PLANNING

36

5.2

MONITOR AND EVALUATE

37

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5.3.1 Dispersant Decision Process 44

5.3.2 Application Methods 49

5.4

IN-SITU BURNING

55

5.5

CONTAINMENT AND RECOVERY

57

5.6

PROTECTION AND DEFLECTION

61

5.6.1 Offshore Protection and Deflection 61

5.6.2 Shoreline Protection and Deflection 61

5.7

SHORELINE CLEAN-UP

63

5.8

OILED WILDLIFE

69

5.8.1 Response Structure and Capability 70

5.8.2 Response Activities 71

5.8.3 Equipment and Facilities 72

5.9

WASTE MANAGEMENT

75

5.10

PTTEP AA OIL SPILL EQUIPMENT

78

5.10.1 Maintenance of Equipment 79

5.11

RESOURCES AND MOBILISATION SUMMARY

79

5.11.1 Aircraft Resources 82

5.11.2 Vessel Resources 83

5.12

NET ENVIRONMENTAL BENEFIT ASSESSMENT

84

6

OPERATIONAL AND SCIENTIFIC MONITORING PROGRAM

91

6.1.1 Implementation 93

6.1.2 Mobilisation 93

7

RESPONSE TERMINATION

95

7.1

RESPONSIBILITY FOR TERMINATING THE RESPONSE

95

7.1.1 Tier 1 95 7.1.2 Tiers 2 and 3 95

7.2

STAND-DOWN PROCEDURES

96

7.2.1 Return of Equipment 96 7.2.2 Debrief 96

7.3

COST RECOVERY

96

8

IMPLEMENTATION

98

8.1

PLAN PERFORMANCE MEASURES

98

8.2

MAINTENANCE OF PTTEP AA RESPONSE PREPAREDNESS

98

8.2.1 Testing 98

8.2.2 Auditing 99

8.2.3 Review and Maintenance 99

8.2.4 Training 99

8.3

MANAGEMENT OF CHANGE

101

8.4

CONSULTATION

101

9

REFERENCES

102

10

ATTACHMENTS

103

10.1

ATTACHMENT A - PTTEP AA EMERGENCY CONTACT DIRECTORY

104

10.2

ATTACHMENT B – EMT ROLES AND RESPONSIBILITIES

107

10.3

ATTACHMENT C – EMT CHECKLISTS

111

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10.5

ATTACHMENT E – INCIDENT ACTION PLAN PROCEDURE

127

10.6

ATTACHMENT F – OIL SPILL EQUIPMENT INVENTORY

131

10.7

ATTACHMENT G – NET ENVIRONMENTAL BENEFIT ASSESSMENT PROCESS 140

10.8

ATTACHMENT H – BONN APEARANCE CODES

147

10.9

ATTACHMENT I – ESTIMATING OIL SLICKS AT SEA

149

10.10

ATTACHMENT J – OPERATIONAL AND SCIENTIFIC MONITORING PROGRAM

151

10.11

ATTACHMENT K – ENVIRONMENTAL INFORMATION

152

10.12

ATTACHMENT L – DISPERSANT FIELD TEST PROCEDURE

169

TABLE OF TABLES

Table 1-1 PTTEP AA Crisis and Emergency Management Plans ... 16

Table 1-2 Associated External Plans ... 16

Table 2-1 Definition of Spill Tiers ... 20

Table 2-2 Statutory and Combat Agencies in WA, NT and adjacent Commonwealth Waters ... 20

Table 2-3 Triggers for Statutory Authorities and Support Organisations to join the EMT ... 21

Table 3-1 Spill Assessment Form ... 25

Table 3-2 Escalation and de-escalation triggers for oil spill response ... 27

Table 4-1 Summary of Spill Scenarios ... 29

Table 4-2 Predicted Shoreline ZPI Contact for all Seasons ... 34

Table 5-1 Monitor and Evaluate Strategy Summary ... 39

Table 5-2 Monitor and Evaluate Objectives, Standards and Measurement Criteria ... 40

Table 5-3 Operational Constraints for Dispersant Application ... 42

Table 5-4 Dispersant application summary (initial five days of a spill response) ... 43

Table 5-5 Dispersant Application Strategy Summary ... 51

Table 5-6 Dispersant application objectives standards and measurement criteria ... 54

Table 5-7 In-situ Burning Strategy Summary ... 57

Table 5-8 In-situ Burning objectives, standards and measurement criteria ... 57

Table 5-9 Operational Constraints for Open Water Containment and Recovery ... 58

Table 5-10 Containment and Recovery Strategy Summary ... 60

Table 5-11 Containment and Recovery objectives, standards and measurement criteria ... 60

Table 5-12 Protection and Deflection Strategy Summary ... 62

Table 5-13 Protection and Deflection Objectives, Standards and Measurement Criteria ... 63

Table 5-14 Shoreline Clean-up Methods ... 66

Table 5-15 Shoreline Clean-up Strategy Summary ... 68

Table 5-16 Shoreline clean-up performance objectives, standards and measurement criteria ... 69

Table 5-17 Proposed response activities. ... 72

Table 5-18 Oiled Wildlife Strategy Summary... 74

Table 5-19 Oiled wildlife performance objectives, standards and measurement criteria ... 75

Table 5-20 Segregation of Wastes ... 76

Table 5-21 Temporary Waste Storage and Handling ... 77

Table 5-22 Waste performance objectives, standards and measurement criteria ... 78

Table 5-23 PTTEP AA Response Equipment for Immediate Deployment ... 78

Table 5-24 Resource and Mobilisation Overview ... 81

Table 5-25 Aircraft Resources ... 82

Table 5-26 PTTEP AA Vessel resources (indicative – exact vessels may change) ... 84

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Table 6-1 Operational Monitoring Studies ... 92

Table 6-2 Scientific Monitoring Studies ... 92

Table 7-1 Indicative Termination Criteria ... 95

Table 8-1 Oil Spill Preparedness performance objectives, standards and measurement criteria ... 99

Table 8-2 Oil Spill Response Training Level for PTTEP AA ... 99

Table 8-3 Oil Spill Response Training Levels for Offshore Personnel ... 100

TABLE OF FIGURES

Figure 1-1 Montara PDW activity location and Key Environmental Features ... 14

Figure 1-2 Montara PDW activity location and Protected Areas ... 15

Figure 2-1 PTTEP AA Emergency and Crisis Management Teams and Support ... 17

Figure 2-2 PTTEP AA Emergency Management Team Structure... 18

Figure 3-1 Reporting Sequence for MODU and supply vessels within 500 m of the MODU ... 24

Figure 3-2 Reporting sequence for supply vessels within the permit area but outside of the 500 m MODU zone ... 26

Figure 4-1 Annual Zone of Potential Impact surface hydrocarbon moderate exposure (10g/m2) from a 84,966 m3_{subsea release of Montara crude over 77 days. ... 31}

Figure 4-2 Predicted movement of an oil spill at 3 days after the initial release for the selected single spill trajectory. Results were calculated from a 84,966 m3_{subsea release of Montara crude over 77 days. ... 32}

Figure 5-1 Basic Response Strategy Process ... 37

Figure 5-2 Dispersant Surface Application Decision Process ... 45

Figure 5-3 Dispersant Sub-surface Application Decision Process ... 48

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DOCUMENT CONTROL - EXTERNAL CONTROLLED COPIES

If you become aware of any changes or corrections that are required please photocopy

this page and the relevant page(s) requiring correction, mark up the corrections and send

them to:

Document Control

PTTEP Australasia (Ashmore Cartier) Pty Ltd

Tel:

Email:

Name:.. ... Position: ... Organisation:…. ... OSCP Controlled Copy Number: ...

Tel: ... Fax: ...

Email: ...………... Please note the changes to details on the attached pages(s):

Section Title: ... Sub Section Title: ... Page Numbers: ... Other Comments: ... ... ... ...

DOCUMENT CONTROL - INTERNAL CONTROLLED COPIES

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DISTRIBUTION LIST

RECIPIENT Copy No Hard (H) or Electronic (E)

PTTEP AA Perth Office

Chief Executive Officer 1 E

SSHE Manager 3 E

Drilling & Well Services Manager 4 E

Drilling SSHE Supervisor 5 H / E

Drilling Supervisor 6 E

Environmental Advisor 7 H / E

C, BS & DI Manager 8 E

Perth EMT

Emergency Management Team Leader 9 H

Crisis Management Room 10 H

Emergency Response Room 11 H

Darwin Support

Darwin Supply & Logistics Base Manager 12 H / E

PTTEP AA Offshore

Senior Drilling Supervisor 13 H / E

Night Drilling Supervisor 14 H / E

SSHE Coach 16 H / E

Ensco Australia Pty Ltd

MODU Manager 17 H

HSE Manager 18 H

Offshore Installation Manager 19 H

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DEFINITIONS AND ABBREVIATIONS

Abbreviation Description

ALARP As Low As Reasonably Practicable

AMSA Australian Maritime Safety Authority

AMOSC The Australian Marine Oil Spill Centre

API American Petroleum Industry

Combat Agency The agency (either industry or government) that directs and manages the spill response in certain situations

CMT Crisis Management Team

CORP Corporate

cP Centipoise

CWLTH Commonwealth

DoE Department of Environment

DPaW Department of Parks and Wildlife

DSEWPAC/SEWPAC/DoE Department of Sustainability, Environment, Water, Population and Communities (now DoE)

EMT Emergency Management Team

EP Environment Plan

ER Emergency Response

ERT Emergency Response Team

FPSO Floating Production, Storage and Offloading Facility

HRs Hours

IAP Incident Action Plan

IBC Intermediate Bulk Container

ICT Information Communication and Technology

IMO International Maritime Organisation

IPIECA International Petroleum Industry Environmental Conservation

Association

ISO International Organisation for Standardisation

ITOPF International Tank Owners Pollution Federation

KG Kilograms

KM Kilometres

M metres

MARPOL International Convention for the Prevention of Pollution from Ships

MOC Management of Change

MODU Mobile Offshore Drilling Unit

MOSES Marine Oil Spill Equipment System

MSDS Material Safety Data Sheet

NAS National Academy of Science

NATPLAN Australian National Plan to Combat Pollution of the Sea and Other

Noxious and Hazardous Substances

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Abbreviation Description

Nm Nautical Miles

NOAA National Oceanic and Atmospheric Administration

NOPSEMA National Offshore Petroleum Safety and Environmental

Management Authority

NRT National Response Team

NT Northern Territory

NT DoR The former Northern Territory Department of Resources

NT DoT Northern Territory Department of Transport

OIM Offshore Installation Manager

OPGGSA Offshore Petroleum and Greenhouse Gas Storage Act 2006

OPGGS(E)R Offshore Petroleum and Greenhouse Gas Storage (Environment)

Regulations 2009

OSCP Oil Spill Contingency Plan

OSMP Operational and Scientific Monitoring Programme

OSR Oil Spill Response

OSRICS Oil Spill Response Incident Control System

OSRL Oil Spill Response Limited

OSTM Oil Spill Trajectory Modelling

PIC Person in Charge

POLREP POLREP – Marine Pollution Report

PPB Parts Per Billion

PTTEP PTT Exploration and Production Public Company Limited

PTTEP AA PTTEP Australasia (Ashmore Cartier) Pty Ltd, being the operator or

the titleholder of AC/L7 and AC/L8 or being the Australian subsidiaries of PTT Exploration and Production Public Company Limited, as the context requires

SARO Search and Rescue Officer

SITREP Situation Report

SSHE Safety, Security, Health and Environment

SOPEP Shipboard Oil Pollution Emergency Plan

Statutory Agency State/NT or Commonwealth agency having statutory authority for marine pollution matters in their area of jurisdiction

WA Western Australia

WA DoT Western Australia Department of Transport

WESTPLAN Western Australian State Emergency Management Plan

WMC Waste Management Coordinator

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SPILL ACTION PLAN – QUICK REFERENCE GUIDE

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EMERGENCY CONTACTS

EMERGENCY CONTACT FOR PTTEP AA EMT LEADER

DEDICATED EMERGENCY RESPONSE TELEPHONE NUMBER (this will divert

to the EMT Leader‘s Mobile) 08 9483 9472

Mobile

_{0467 795 002}

OTHER EMERGENCY CONTACTS

Agency

24 Hour Number

Telephone

AMSA (Rescue Coordination Centre)

NT DLP

Port of Darwin

AMOSC

NOPSEMA

WA DoT

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1

INTRODUCTION

PTTEP AA is engaged in petroleum exploration, development and production activities in the offshore area of the Territory of the Ashmore and Cartier Islands under the Offshore Petroleum and Greenhouse Gas Storage Act 2006 (OPGGS Act) (Cwlth).

PTTEP AA is the operator of the Licence Areas AC/L7 and AC/L8 located in the Bonaparte Basin, in the East Timor Sea.

1.1

PURPOSE AND OBJECTIVE

The purpose of this OSCP is to detail the procedures and resources through which PTTEP AA will minimise the effect of any marine oil spill from the periodic Montara production drilling and well workovers (PDW) within the Timor Sea.

This aim is achieved through the implementation of rapid, effective and appropriate response procedures, in particular:

 ensuring that the procedures used by PTTEP AA personnel are consistent with those detailed in the National Plan to Combat Pollution of the Sea by Oil and other Noxious and Hazardous Substances (the ‗NatPlan‘), Western Australian Department of Transport (WA DoT) WestPlan and NT Oil Spill Contingency Plan;

 achieving a full and effective integration and utilisation of PTTEP AA, industry, State/NT and national response resources; and

 rapid identification of protection and clean-up priorities.

This OSCP is designed for use by the PTTEP AA Emergency Management Team.

1.2

SCOPE

This OSCP applies to all PTTEP AA Montara PDW activities located in the AC/L7 and AC/L8 licence areas, as described in Section 1.3 and in greater detail in Section 4 of the Environment

Plan (

for an effective response to an unplanned release of petroleum products or petroleum based chemicals used during the periodic PDW activities. PTTEP AA is the combat agency for all spills associated with the Montara drilling activities with the exception of spills originating from vessels outside of the Montara PDW activities 500 m exclusion zone.

The Australian Maritime Safety Authority (AMSA) is the designated Combat Agency for all vessel-sourced spills in Commonwealth waters. AMSA will assume control upon notification of a vessel incident, as specified in the NatPlan. Therefore, incident planning for vessels outside of the 500 m operations exclusion zone will not be covered in detail in this OSCP.

1.3

DESCRIPTION OF THE ACTIVITY AND ENVIRONMENT

1.3.1 Description of Activity

This OSCP deals with spills arising from periodic PDW activities. Refer to Section 4 of the

corresponding EP ) for further detail on the nature of drilling and workover

activities.

1.3.2 Description of the Environment

A detailed discussion of the local and regional environments, including the location of the physical, biological and socio-economic receptors in the area of interest for operations is include in the EP (Sections 5). The key values and attributes identified at the sensitive receptor locations which may be affected by the activity and have been incorporated into the planning of this OSCP include the following:

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Technical#810827 Rev 4 Page 13 of 169 • physical environment: Seabed and water quality;

• ecological: Benthic communities, shoals, reefs, islands, marine flora, fish, marine reptiles, marine megafauna and seabirds; and

• socio-economic: Heritage, protected areas, commercial, recreational and traditional fishing and commercial shipping.

The location of the key environmental features and protected areas in relation to the Montara PDW activities are shown in Figure 1-1 and Figure 1-2 respectively.

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1.4

INTEGRATION WITH OTHER PLANS

1.4.1 PTTEP AA Plans

This OSCP interfaces with other relevant PTTEP AA crisis and emergency plans as detailed in Table 1-1.

Table 1-1 PTTEP AA Crisis and Emergency Management Plans

Title Document Number Scope and Function

PTTEP AA SSHE

Management System Describes the way in which security, safety, health and the environment is managed in PTTEP AA. PTTEP Crisis

Management Plan Company-wide plan setting out Crisis Management Team procedures. PTTEP AA

Emergency Management

Covers company-wide emergency management. Integrated with facility and project EMPs.

PTTEP AA Montara Drilling Environment Plan

Sets out environmental management requirements for the Montara production drilling and well workovers

Vessel SOPEPS As per contractor

document control. Shipboard Oil Pollution Emergency Plans as per MARPOL requirements

1.4.2 External Plans

The OSCP is integrated with a number of government plans as well as oil industry mutual assistance plans. These are listed in Table 1-2.

Table 1-2 Associated External Plans

Jurisdiction Plan Title Administering

Agency Function / Application

Industry (all waters)

Australian Marine Oil Spill

Centre Plan (AMOS Plan) AMOSC Sets out industry arrangements for mutual aid and access to AMOSC resources.

Commonwealth of Australia (Commonwealth Waters)

National Plan for Maritime Environmental

Emergencies (NatPlan)

AMSA Sets out oil spill preparedness and response procedures under the National Plan.

Northern

Territory NT Marine Oil Pollution Manual NT Dept. of Transport Sets out NT arrangements for marine oil spill preparedness and response.

NT Oil Spill Contingency Plan

NT Wildlife Response Plan

for Oil Spills NT NRETAS Implemented by the Oiled Wildlife co-ordinator within the NT Incident Management Team.

Western

Australia WA Marine Oil Pollution Management Plan (WestPlan-MOP)

WA Dept. of

Transport Response to oil in WA waters. WA Marine Hazardous

Materials Emergency Management Plan (WestPlan-HAZMAT)

Response to spills of non-oil chemicals or other hazardous substances.

WA Oiled Wildlife Plan WA Dept. Parks

and Wildlife Response plan for managing oiled wildlife in Western Australian waters.

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2

EMERGENCY RESPONSE ARRANGEMENTS

2.1

PTTEP AA CRISIS AND EMERGENCY ORGANISATION

Crisis and emergency response is managed by a hierarchy of teams within PTTEP AA, supported by the resources of PTTEP‘s Head Office in Bangkok, Thailand (Figure 2-1).

Figure 2-1 PTTEP AA Emergency and Crisis Management Teams and Support

2.1.1 Emergency Management Team

The structure and operations of the PTTEP AA EMT are consistent with the Oil Spill Response Incident Control System (OSRICS) as set out in the National Marine Oil Spill Contingency Plan. The EMT addresses tactical response issues in an emergency, interfacing with and providing information to internal and external parties including the CMT, Contractors, Joint Venture Partners and the relevant regulatory authorities.

The size and organisation of the EMT will depend on the nature of the incident and the anticipated response. The basic organisation will be as per Figure 2-2.

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Technical#810827 Rev 4 Page 18 of 169 Figure 2-2 PTTEP AA Emergency Management Team Structure

The EMT generates tactical objectives, determines response priorities, ensures that emergency response operations are performed in a safe manner, interacts with senior company representatives, relevant regulatory authorities, and the public. The EMT also prompts for personnel, relative and /or media matters through the CMT.

In event the EMT is activated, the team shall gather at the Emergency Response Room (Board Room, 1st Floor of PTTEP AA Perth Office). The roles and responsibilities of the Emergency Management Team are nominated from the EMT Duty Roster Group with the roles defined in the

PTTEP AA Emergency Management Plan ) and summarised in Attachment

B.

AMSA and AMOSC will be the key support agencies for Tier 2 and 3 spill scenarios. Support from OSRL will be requested as required.

AMSA will provide support as specified under the National Plan arrangements. AMSA will provide a liaison officer to the PTTEP AA EMT to enable this support role.

AMOSC will also provide a liaison officer within the EMT, whose role will be to provide technical advice to the EMT Leader, Planning Coordinator and Operations Coordinator, coordinate AMOS Plan resources and manage deployment in cooperation with AMSA liaison officer (for Tier 2 and 3 spills).

2.1.2 Crisis Management Team

The PTTEP AA CMT is based in Perth and is responsible for proactively identifying and managing strategic issues associated with the incident.

The CMT comprises senior PTTEP AA personnel supported by technical specialists as required for the incident.

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Technical#810827 Rev 4 Page 19 of 169  identify the short and long term strategic implications of the emergency for PTTEP AA

corporate image, operability and commercial position;

 develop, resource and initiate appropriate strategies to limit potentially adverse consequences for PTTEP AA arising from the emergency; and

 develop and implement a long term recovery plan.

The roles of the CMT are detailed in Section 6.5 of the Crisis Management Plan ( ).

2.1.3 CMT and EMT Support Groups

The emergency support groups provide detailed support to the EMT and CMT on a variety of areas. Under the direction of the EMT Leader they work closely with the EMT and CMT in order to ensure a consistent and comprehensive output.

The EMT and CMT support groups are described in Section 6.3 of the PTTEP Emergency

Management Plan ) and includes the following to be setup as required:

 Employee and Relative Response Group;  Media and External Affairs Group;

 Technical Support Group and;  Administration Support Group.

The EMT leader may also request support from the following personnel:  Project Leader – Perth;

 Project Leader – corporate;  Drilling Team Leader;

 Information, Communication and Technology (ICT) Leader; and  Other service providers as required.

2.2

STATUTORY REQUIREMENTS AND SPILL RESPONSE AUTHORITIES

Response and preparedness requirements for potential spills of hydrocarbon resulting from offshore petroleum activities undertaken in Commonwealth waters are provided for under the

Offshore Petroleum and Greenhouse Gas Storage Act 2006 and Offshore Petroleum and Greenhouse Gas Storage (Environment) Regulations 2009 (most notably with regard to Section 14 (8)).

This OSCP has been developed to meet the requirements of the OPGGSA and OPGGS(E)R, but also meets the requirements of other relevant Commonwealth and state legislation including:  The Protection of the Sea (Prevention of Pollution by Ships) Act 1983 (Cth); and  Environment Protection and Biodiversity Conservation Act 1999 (Cth).

2.2.1 Definition of Tier Levels

Under the NatPlan arrangements, oil spills and their response requirements are categorised into three ‗Tiers‘ as summarised in Table 2-1 with the applicable Montara PDW activities potential spill scenarios provided for guidance.

The tier, location and trajectory of the spill influences the PTTEP AA and external resources involved in the spill response and notifications required.

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Technical#810827 Rev 4 Page 20 of 169 Table 2-1 Definition of Spill Tiers

Tier Approximate

Volumes Tier Definition Applicable Montara Spill Scenarios Tier 1 0-10 tonnes

0 – 70 bbl 0 – 10 m3

A small spill requiring a local response:

The Combat Agency will generally be able to respond to and clean up a spill utilising local resources.

Flare drop out

General operations e.g. hydrocarbon transfers Oily water discharges

Fuel spill – bunkering /refuelling (crude/diesel – max volume 5 m3₎

Tier 2 10-1000 tonnes

71 – 7000 bbl 10 – 1000 m3

A medium spill requiring a regional response and/or national assistance:

The resources of the Combat Agency will need to be

supplemented by other resources from intrastate and possibly interstate.

Vessel collision and fuel tank rupture

(diesel - max volume 80 m3₎

Tier 3 >1000 tonnes

>7000 bbl >1000 m3

A large spill requiring national assistance:

The Combat Agency will require local, regional, national and possibly international assistance.

Loss of well control – blow out (crude - max volume 84,966 m3)

2.2.2 Statutory Authority and Combat Agency

A Statutory Agency and a Combat Agency are designated for spills offshore depending on their size and nature, categorised as either Tier 1, 2 or 3.

The Statutory Agency has the remit to monitor the Combat Agency in preparing for and responding to spills and to advise operators on their response. The Combat Agency is the entity having operational responsibility in accordance with the relevant contingency plan. These are detailed in Table 2-2.

In the event of an oil spill arising during Montara PDW activities, PTTEP AA will assume Combat Agency responsibilities.

Table 2-2 Statutory and Combat Agencies in WA, NT and adjacent Commonwealth Waters Location of Incident Spill

Source/ Location Statutory Agency Combat Agency Commonwealth Waters (>3nm offshore)

MODU NOPSEMA PTTEP AA

Vessel at sea AMSA AMSA*

NT Waters (<3nm

from land) Vessels at sea NT DoT NT DoT

WA Waters

(<3nm from land) Vessel at sea WA DoT WA DoT

*In the event of a Tier 1 vessel spill within the 500m zone, PTTEP AA will deploy first strike resources to assist spill clean up (refer to Section 5)

The provision of resources for any tier of oil spill event response will be coordinated by PTTEP AA EMT. In the event of Tier 2 or 3 responses, PTTEP AA may require support from statutory authorities and support agencies.

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Technical#810827 Rev 4 Page 21 of 169 The support agencies will be requested to join the EMT at the commencement of an incident. Triggers for inviting the support agencies into the EMT are provided in Table 2-3.

Table 2-3 Triggers for Statutory Authorities and Support Organisations to join the EMT Support Trigger to join the EMT

AMSA Spill response activated or requiring National Plan Resources

An event which has, in the opinion of the EMT Leader, the potential to escalate into a Tier 2 or Tier 3 spill

AMOSC and OSRL

Tier 2 or Tier 3 spill requiring AMOSC support and Core Group members or specialist OSRL Resources

An event which has, in the opinion of the EMT Leader, the potential to escalate into a Tier 2 or Tier 3 spill

WA and

NT DoT Spill has potential to enter WA State / NT Waters

In the event of a spill potentially reaching international waters, PTTEP AA will contact the Department of Foreign Affairs and Trading to ensure the appropriate notifications are made.

2.2.3 NOPSEMA

The function of the NOPSEMA includes regulation of environmental management of offshore petroleum activities in the Commonwealth offshore areas and in coastal waters where State and Northern Territory powers have been conferred.

NOPSEMA is the National Authority for offshore petroleum activities and a Statutory Authority under the National Plan. In these roles, NOPSEMA is responsible for the oversight of response actions to pollution events from offshore petroleum operations (excluding vessel-only spills) in areas of Commonwealth jurisdiction.

2.2.4 AMSA

AMSA manages the NatPlan, which has been developed in consultation with State / Northern Territory government, the shipping, oil and gas exploration and production companies, chemical industries and emergency service organisations to maximise Australia‘s marine pollution response capability.

AMSA is responsible for a range of services that are directly relevant to oil spill operations including ordination of National Response Team resources (up to 60 people) and the provision and co-ordination of personnel, equipment and aerial surveillance resources.

The NatPlan, incorporating AMSA, State/NT authorities and industry, conducts regular training programs and exercises for personnel likely to be involved in a response to an oil spill in the marine environment. These training programs and exercises are designed to enable Australia to have sufficient numbers of trained personnel to mount a credible and effective response to an oil spill incident during PTTEP AA operations.

Training programs are conducted at three levels, which recognise the overall technical complexity of managing an oil spill response and that the associated knowledge required by personnel varies depending on their level of responsibilities. The three levels of training conducted are:

 Level 1: Operator level personnel, i.e. those undertaking on-site clean-up operations, in a major incident this would also include supervisors appointed as site managers;

 _{Level 2: Middle management personnel responsible for managing the operational response,} e.g. incident controllers, their deputies and environment and scientific coordinators, and Fire Brigade (Hazardous Materials) specialists; and

 _{Level 3: Senior government and industry personnel responsible for high level decision-making} in the management of oil or chemical spill incidents.

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2.2.5 Department of Environment

The Department Environment (DoE‘s) role is to assess projects that may, will or are likely to have a significant impact on matters of national environmental significance. This project was assessed and approved by the delegate of the then Minister for Environment and Heritage on 3 September 2003. The DoE also has a role in monitoring compliance with the conditions of approval issued under the

Environment Protection and Biodiversity Act 1999, including compliance with management plans such as Oil Spill Contingency Plans

The DoE requires spill incidents of 80L or above to reported within 48 hours of the spill occurring on the Department‘s Compliance Hotline for this purpose. The phone number is 1800 110 395 (note that this is not available 24 hours).

2.2.6 State/Territory Authorities

2.2.6.1 Northern Territory Department of Transport

The Northern Territory Department of Transport (NT DoT) through the Marine Safety Branch is responsible for marine pollution prevention and response activities in the NT. The Marine Safety Branch administers the NT Marine Pollution Act (as in force October 2004). The NT Department of Transport, Marine Branch (DLP Marine) manages marine oil pollution response. The Marine Safety Branch on behalf of the NT DoT is responsible for the NT Marine Pollution Contingency Plan which supports the National Plan.

As Statutory Authority for marine oil pollution in NT waters, DLP Marine will:  maintain an adequate level of response preparedness in the NT;  maintain the NT Plan;

 monitor all spills and spill responses;

 provide support for Company Combat Agencies;

 coordinate the supply of NT equipment and personnel for oil spill response if required;  undertake investigations and prosecutions; and

 facilitate activation of suitable recovery procedures, including:

o assisting in the recovery of costs on behalf of all participating agencies; o facilitating damages claims from the public or commercial operators;

o _{coordinate the provision and deployment of NT equipment and personnel contributing to} an interstate or Commonwealth response.

2.2.6.2 Western Australian Department of Transport

The WA DoT is the Hazard Management Authority for oil pollution in WA State waters. The DoT coordinates the State Response Team oil spill response personnel and equipment resources. In the event that an oil spill (for which PTTEP AA is the combat agency) impacts shorelines in WA the DoT will work with PTTEP AA in shoreline operations, and the DoT will define endpoints in liaison with PTTEP AA that are as low as reasonably practical (ALARP).

In the event that there is potential for an oil spill to intersect state waters then DoT will implement WestPlan-marine oil pollution (MOP) and oil spill contingency plan.

WestPlan-MOP details the management arrangements for preparation and response to a marine oil pollution incident in order to minimise the effects of oil pollution occurring in State Waters. Also relevant are the WA Hazardous Materials Emergency Management Plan (WestPlan-HAZMAT) and WA Oiled Wildlife Plan, administered by the WA Fire and Emergency Services (FESA) and Department of Parks and Wildlife (DPaW) respectively.

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2.3

INDUSTRY ARRANGEMENTS

2.3.1 Australian Marine Oil Spill Centre (AMOSC)

Industry assistance is available through the Australian Marine Oil Spill Centre (AMSOC), an industry funded response facility based in Fremantle, Western Australia and Geelong, Victoria. As a member company of AMOSC, PTTEP AA has access to AMOSC‘s oil spill recovery and response equipment (refer to Attachment F), training, dispersant and technical capabilities along with those resources held by member companies as outlined in the AMOSPlan.

The EMT leader has authorisation to request the mobilisation of AMOSC resources.

AMOSC support is facilitated through the AMOSPlan using various legal instruments signed by all members.

The AMOSPlan also provides a link into the NatPlan (AMSA) resources.

AMOSC Core Group of up to 100 personnel re-validate their competencies every 2 years through additional training and exercises at AMOSC and relies on competence based training for its skill-base. This ensures personnel have appropriate training and competency for oil spill response to ensure tasks, for example offshore containment and recovery, shoreline protection and deflection and dispersant operations can be completed effectively. AMOSC Core Group personnel provide the surge capability in response to a Tier 2 or 3 spill.

AMOSC will supply a liaison person directly to the EMT to assist the EMT Leader and Planning and Operations Co-ordinators.

2.3.2

Through PTTEP, PTTEP AA has access to additional oil spill resources through

), which is based in Singapore and Southampton. If required, PTTEP AA has access to 50% of oil spill response equipment (refer to Attachment F). Both the CEO and SSHE Manager have approval to officially request and activate support from in the event of a Tier 3 spill.

L can provide up to 32 trained personnel (16 per rotation) to assist with response in the event of an oil spill. These personnel can be mobilised from Singapore to Australia in less than 24 hours.

personnel can assist and provide technical advice to the PTTEP AA EMT as required. In addition, these personnel can be mobilised in the field as they are trained in operational activities such as containment and recovery, aerial surveillance, flurometric monitoring, shoreline assessment and clean-up. L can also provide satellite imagery every 12 hours in the event of a spill occurring.

If required, AMOSC will coordinate and facilitate assistance on behalf of the PTTEP AA EMT.

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3

INITIAL RESPONSE ACTIONS

This section provides guidance on the immediate response actions in the event of a spill and covers:

 reporting and notifications:

o _{reporting of spill to the MODU OIM;}

o MODU OIM notifying PTTEP AA Drilling Supervisor immediately; o reporting to PTTEP AA, and activation of the EMT;

o _{reporting to regulatory agencies;}  initial assessment of spill; and

 response escalation and de-escalation.

3.1

REPORTING AND NOTIFICATION

All PTTEP AA staff and contractors must report spills or observations of oil or oily substances on the sea immediately to the MODU OIM.

On a vessel, the observer must notify the Vessel Master, which in turn will notify the MODU OIM if within the 500 m of the MODU.

Reporting and notification shall be in accordance with PTTEP AA‘s Incident Reporting and Investigation Procedure (S32-500311-CORP).

Spills from the MODU with a response activated or requiring NatPlan resources must be reported to AMSA as soon as possible in readiness for activation of the AMSA support role. A POLREP form (Attachment D) is required to be sent to AMSA by the MODU OIM in order to provide details of the spill.

Figure 3-1 outlines the notification process for a spill within the MODU 500 m zone.

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Technical#810827 Rev 4 Page 25 of 169 The MODU OIM will make an initial evaluation and estimation of the magnitude and Tier level of the spill and whether the spill has a potential to escalate to a higher Tier level. The guidance for evaluation of the Tier level is provided in Table 2-1. The MODU OIM will notify the Drilling Supervisor immediately, the Drilling Supervisor will then contact the EMT Leader if EMT assistance is required.

The spill assessment form (Table 3-1) should be completed immediately by the MODU OIM to aid the response teams (onsite Emergency Response Team coordinated by MODU OIM and/or EMT under leadership of EMT Leader).

Table 3-1 Spill Assessment Form

Question Prompt / Answer

1 Name of Reporter 2a

Contact Details Telephone No: Bus: A/H:

2b Fax/Email:

3 Position of observer when sighting _made

Aircraft_____________ Vessel_______________ Ground__________________________________ Other (details)____________________________ 4 Position of the slick

5 Source of spill (if known) 6 Type of substance spilled

(if known)

7 Amount of substance spilled (if known) 8a Description of slick General 8b Colour Black_______________ Brown_______________ Rainbow_________________________________ Silver____________ Other (specify)______________________ 8c Area Length______________(m) _{Width_______________(m)}

8d Other

Broken up? Yes___________ No_____________ Windrows (Streaks)?

Yes_________________ No__________________

9 Direction of slick movement (if known)

10 Weather / sea conditions 11 Other information

12 Name of person receiving report 13 Agency / Division / Role

14 Report to be forwarded to Name

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Technical#810827 Rev 4 Page 26 of 169 NOPSEMA is required to be notified of spills from the Montara PDW activities, the type of spills and required timeframes are detailed below. NOPSEMA‘s contact number for reporting an environmental incident is

Spills from the MODU and vessel spills within the 500 m MODU zone must be reported to NOPSEMA as follows:

 Spills greater than 80 litres must be reported to NOPSEMA by the MODU OIM verbally within 2 hrs. A written report of the event must be provided to NOPSEMA within 3 days.

 Spills greater than 80 litres must be reported to the PTTEP AA Drilling Supervisor by the MODU OIM verbally within 2 hrs.

 Spills less than 80 litres must be reported to the PTTEP AA Drilling SSHE Supervisor who will ensure that NOPSEMA receives a written report within 15 days of the end of the reporting month.

All vessel spills, regardless of location, must be reported to AMSA, the combat agency for all Tiers. For support vessel spills under contract by PTTEP AA within the permit area but outside of the 500 m MODU zone, they must report directly to the PTTEP AA Drilling Supervisor as per Figure 3-2. A POLREP form (Attachment D) is required to be sent to AMSA by the vessel master in order to provide details of the spill.

AMSA‘s contact number for reporting any marine pollution is (02) 6230 6811 or 1800 641 792.

Figure 3-2 Reporting sequence for supply vessels within the permit area but outside of the 500 m MODU zone

If a spill has the potential to enter WA or NT State Waters, the relevant state departments must also be informed by the EMT leader on the below reporting contact numbers.

 WA DoT:

 WA DPaW:

 WA DER:

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Technical#810827 Rev 4 Page 27 of 169 In addition, the DoE requires spill incidents of 80L or above to reported within 48 hours of the spill occurring on the Department‘s Compliance Hotline for this purpose. The phone number is 1800 110 395 (note that this is not available 24 hours).

3.2

ESCALATION AND DE-ESCALATION OF RESPONSE TIERS

After the spill has initially been reported to the Person in Charge (PIC) (MODU OIM or Drilling Supervisor), the PIC is required to make the initial assessment of the spill tier, and maintain responsibility for de-escalation and termination of the response if Tier 1. The EMT will be responsible for escalation and de-escalation in the event of Tier 2 or 3 spills.

The EMT Leader is responsible for defining the response tier upon establishment of the EMT, ongoing assessment of the incident and the defined tier level, including escalation and de-escalation considerations, and ultimately terminating the incident response.

The escalation and de-escalation response triggers for this OSCP are: Table 3-2 Escalation and de-escalation triggers for oil spill response

Escalation Triggers De-escalation Triggers

The spill moves or is predicted to move outside of the ZPI Hydrocarbon source is under control A volume greater than 10 m3 has been released will

escalate the spill from Tier 1 to Tier 2 The NEBA determines that continued response activities will have no further net environmental benefit

A volume greater than 1000 m3_{has been released will}

escalate the spill from Tier 2 to Tier 3 incident Endpoint criteria for response strategies in Section 4 have been met The surface slick is predicted to reach a shoreline will

escalate the event to a Tier 3

For classification of Tier levels for spills from the PDW activities, refer to Section 2.2.1.

3.3

INCIDENT ACTION PLAN

In the event of a Tier 2 or 3 spill, the EMT leader will develop an Incident Action Plan (IAP) (IAP Procedure - Attachment E) with input from supporting units of the EMT team and Planning Co-ordinator (refer to EMT Role Checklists in Attachment B).

The main steps in planning the response and preparing the IAP are:

 response policy and aim: this is a broad statement of the over-riding aim of the response, it should also set priorities;

 objectives – these comprise a goal statement and indicate desired individual outcomes of the response;

 describe the strategies – these describe how the EMT plan to reach the stated objectives; and  methods (tactics) – these state how the strategies will be undertaken and may be written as a

series of tasks.

The IAP is a key step in managing any significant response, recognising that all incidents are different and will be subject to variable factors such as weather, timing (seasons), sea state, duration, size and nature of release. The purpose of the IAP is to consider all of these variable and changing factors, to ensure the response continues to be suitable for the event.

There are a range of scenarios that the EMT may need to respond to, and the IAP allows a structured approach to the challenge facing the team, and the resources available to respond to the incident. The Planning Coordinator will ensure monitoring of the IAP with input from the Operations Coordinator and Logistics Coordinator in consultation with the EMT Leader. This includes consolidation of the IAP aims, objectives, strategies and tactics developed by the EMT under the direction of the EMT Leader

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Technical#810827 Rev 4 Page 28 of 169 The IAP will cover operational monitoring and focuses on obtaining timely information such that physical analysis can be carried out to assess efficiency of response or to predict oil behaviour (weathering) or effects. Long term scientific monitoring will be undertaken in accordance with the Operational and Scientific Monitoring Program (Attachment J).

It will detail the response mechanisms and priority areas for protection based on the actual circumstances of the event, taking into account the spill trajectory, weather conditions, but also importantly safety considerations.

For the PDW activities, given the range of potential impacts from a sub-surface release event, an IAP is a critical step identified in the response strategy. Key activities to be addressed by the IAP include a review of the Net Environmental Benefit Assessment (NEBA) (Section 5), remodelling of oil spill trajectory modelling with relevant spill and environmental data (Section 4), and ongoing consultation with affected/involved parties that may be required (see Section 9 of the Montara Operations EP). To ensure that the IAP is appropriate for the nature of the spill, PTTEP AA proposes to seek the advisory support of technical experts as nominated by AMSA, AMOSC and operators with activities within the ZPI.

These experts will provide advice and support to the EMT Leader in the development of an IAP in areas including (but not limited to):

 monitoring and evaluate;  dispersant application;  containment and recovery;  in-situ burning;

 shoreline clean-up;

 environmental monitoring; and

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4

FATE OF SPILT HYDROCARBONS

The purpose of this section is to set the context for development of response arrangements outlined in subsequent sections of this OSCP.

4.1

SPILL SCENARIOS

As part of the risk assessment process, six potential hydrocarbon spills were identified for Montara PDW activities. The different types of spills could be classified in to three categories being: subsea (crude), surface (diesel) and surface (crude).

Further information on the six worst case spill scenarios, associated maximum spill volumes, model settings and assumptions are detailed in Section 7 of the EP and summarised with assessed Tier level below in Table 4-1.

Table 4-1 Summary of Spill Scenarios

Scenario

ID Incident Source/Location Oil Type Maximum Credible

Volume (m3₎

Tier

A Flare drop out Well bore clean-up Montara Crude <0.05 1

B General

operations e.g. hydrocarbon transfers

MODU and Supply

Vessels Diesel, lubricating oil, aviation fuel, waste oil

< 0.05 1

C Oily water

discharges MODU Diesel, lubricating oil, waste oil < 0.05 1 D Fuel spill – bunkering /refuelling MODU Diesel ~ 5 1 E Collision and/or sinking of support vessel leading to tank rupture

Supply Vessel(s) Diesel ~ 80 2

F Loss of well

control – blow out MODU Montara Crude 84,966 _{(534, 380 bbls)} over 77 days

3

Scenarios E (80 m3_{diesel) and F (}_84,966_m3_{crude) were then modelled as they presented the}

worst case scenario for the category of spill it represents, consequently providing the worst case Zones of Potential Impact (ZPI).

4.2

HYDROCARBON PROPERTIES

PTTEP AA commissioned Asia Pacific Applied Science Associates ( to undertake hydrocarbon spill modelling of two hydrocarbons release scenarios, being Scenario E (80 m3 diesel – vessel collision) and F (84,966 m3_{- loss of well control). As part of this modelling, the}

characteristic oil properties were defined for the diesel and crude oil.

The diesel oil used in the modelling study was based on the formulation used for typical operation of diesel fuel engines in the North West Shelf and Timor Sea. This type of diesel would have an initial API of 38 (or 829 kg/ m3_{) and a dynamic viscosity of 1.15 cP at 25}o_{C. Diesel fuel oil only has}

5% residual or persistent components when spilled into the marine environment. These persistent hydrocarbons will not readily evaporate with the heavier components tending to entrain in the upper water column as oil droplets in the presence of moderate winds (i.e. >12 knots) and breaking waves, but can re-float to the surface if these energies abate.

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Technical#810827 Rev 4 Page 30 of 169 The use of Montara crude for spill modelling instead of the Skua, Swift and Swallow field oils or a blend is considered conservative due to the more persistent nature of Montara crude (higher density and wax content) than those from Skua, Swift and Swallow fields.

The Montara crude is a medium crude oil (API of 35.8°, density of 845 kg/ m3 at 25°C) with a low viscosity (4.5 cP), which is categorised as a Group III oil (ITOPF). The Montara crude has a significant portion of residual components (27%), which means under certain conditions (i.e. exposure to weathering) it can solidify into small waxy flakes.

4.3

ZONE OF POTENTIAL IMPACT

Definition of a Zone of Potential Impact (ZPI) allows identification of potential sensitive receptors which may be affected by harmful hydrocarbon concentrations associated with an oil spill in order to manage risks to those receptors to ALARP during a spill response. Section 7 of the EP provides an extensive discussion around the ZPI from both scenario E and F modelled.

The ZPI relates to the area that could potentially be impacted by spilled hydrocarbons. The two ZPI‘s are:

 surface exposure or within the water column (dissolved and entrained hydrocarbons); and  shoreline contact.

It is recognised that the spatial extent of the ZPI is influenced by environmental conditions (i.e. wind and currents). To account for these conditions, the potential impact of the spill scenarios have been considered for each of the three main seasons – summer, transition and winter.

As discussed in section 7 of the EP, the annual sea surface exposure ZPI for the loss of well control features the largest impact envelope and has therefore been used to formulate the response strategies within this plan. This sea surface hydrocarbon exposure is based on a threshold of 10 g/m2_{as this represents surface hydrocarbons viable for response strategies and}

potential environmental impacts. Small patches of sea surface exposure above the threshold of 10 g/m2 are located outside of the main ZPI, these spot slicks are of low probability.

Dissolved and entrained hydrocarbons have not been presented as part of the ZPI. This is due to their smaller impact envelope as detailed within section 7 of the EP.

The discussion of potential impacts of spills from the Montara PDW activities, the Net Environmental Benefit Assessment (NEBA), and development of appropriate response strategies in this OSCP are based on the following sea surface exposure ZPI and associated volumes of stranded oil ashore.

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Technical#810827 Rev 4 Page 31 of 169 Figure 4-1 Annual Zone of Potential Impact surface hydrocarbon moderate exposure

(10g/m2) from a 84,966 m3 subsea release of Montara crude over 77 days.

The worst case single scenario from a 84,966 m3 subsea release of Montara crude over 77 days is illustrated below in Figure 4-2 through Figure 4-5. This worst case single scenario illustrates how distinct spot slicks of surface oil form on the sea surface in the first seven days (Figure 4-2 and Figure 4-3) that exceed 10 g/m2_.

After seven days, the frequency of spot slicks with a concentration greater than 10 g/m2 reduce as the rate of release decreases and the oil becomes influenced by surface winds and currents. As a result of this, a number of response strategies will target the area close to the release site with concentrations of sea surface exposure greater than 10 g/m2_{, this will aim to minimise the volume}

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Technical#810827 Rev 4 Page 32 of 169 Figure 4-2 Predicted movement of an oil spill at 3 days after the initial release for the

selected single spill trajectory. Results were calculated from a 84,966 m3_{subsea release of} Montara crude over 77 days.

Figure 4-3 Predicted movement of an oil spill at 7 days after the initial release for the selected single spill trajectory. Results were calculated from a 84,966 m3 subsea release of Montara crude over 77 days.

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Technical#810827 Rev 4 Page 33 of 169 Figure 4-4 Predicted movement of an oil spill at 15 days after the initial release for the selected single spill trajectory. Results were calculated from a 84,966 m3_{subsea release of} Montara crude over 77 days.

Figure 4-5 Predicted movement of an oil spill at 35 days after the initial release for the selected single spill trajectory. Results were calculated from a 84,966 m3_{subsea release of} Montara crude over 77 days.

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Technical#810827 Rev 4 Page 34 of 169 Modelling has shown that if no spill response measures are implemented, the trajectory of the spilled Montara crude has the potential to contact shorelines in proximity to the Montara PDW activities, this forms the shoreline contact ZPI.

In the case of a spill, all predicted shoreline contact based on real time modelling will be considered as part of the NEBA process including the operational and scientific monitoring programs.

All shoreline contact is considered as part of the ZPI. Shorelines contacted are presented in Table 4-2.

Table 4-2 Predicted Shoreline ZPI Contact for all Seasons

Shoreline

Location Maximum Probability of

Contact (%)

Minimum Time

Before Visible Oil

Coming Ashore (hours) Maximum Peak Load on Shoreline (g/m2) Average Load on Shoreline (g/m2₎ Adele Island 4 (Summer) 1076 (Summer) 788 (Summer) 231 (Summer) Browse Island 42 (Transitional) 373 (Transitional) 3230 (Summer) 592 (Summer) Scott Reef

South 52 (Transitional) 330 (Winter) 3773 (Transitional) 583 (Transitional) Scott Reef

North 40 (Transitional) 344 (Winter) 7265 (Winter) 186 (Summer) Seringapatam

Reef 60 (Winter) 306 (Winter) 5103 (Summer) 407 (Summer)

Cartier Island 100 (Winter) 122 (Winter) 6545 (Summer) 916 (Winter) Ashmore

Island 100 (Winter) 232 (Winter) 7264 (Transitional) 1227 (Transitional) Hibernia Reef 86 (Transitional) 192 (Winter) 6118 (Winter) 1022 (Winter) Melville Island 48 (Summer) 849 (Summer) 2509 (Transitional) 690 (Transitional) Rote 32 (Transitional) 314 (Transitional) 3657 (Summer) 140 (Winter) Sawu 14 (Winter) 826 (Transitional) 6746 (Transitional) 121 (Transitional) Sumba 16 (Transitional) 669 (Transitional) 1764 (Transitional) 46 (Transitional) Lombok 8 (Transitional) 1067 (Transitional) 559 (Transitional) 14 (Transitional) Sermata 18 (Summer) 715 (Summer) 461 (Summer) 21 (Transitional)

Leti 30 (Summer) 592 (Summer) 1008 (Summer) 61 (Transitional)

Moa 20 (Summer) 603 (Summer) 945 (Transitional) 114 (Transitional) Masela 10 (Transitional) 1110 (Summer) 561 (Summer) 26 (Summer)

Selaru 24 (Summer) 1285 (Summer) 651 (Summer) 21 (Summer)

Babar 18 (Summer) 906 (Summer) 300 (Transitional) 12 (Summer) Flores 2 (Winter) 1127 (Transitional) 147 (Winter) 11 (Winter)

Yamdena 14 (Summer) 1364 (Summer) 484 (Summer) 13 (Summer)

Sandy Islet 20 (Transitional) 579 (Winter) 1851 (Summer) 418 (Summer) Joseph

Bonaparte Gulf 6 (Summer) 1591 (Summer) 1465 (Summer) 41 (Summer) Sumbawa 14 (Transitional) 1000 (Transitional) 3227 (Transitional) 177 (Transitional) Nusapenida 6 (Transitional) 1053 (Transitional) 548 (Transitional) 31 (Transitional)

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Technical#810827 Rev 4 Page 35 of 169 Shoreline

Location Maximum Probability of

Contact (%)

Minimum Time

Before Visible Oil

Coming Ashore (hours) Maximum Peak Load on Shoreline (g/m2₎ Average Load on Shoreline (g/m2₎ Bathurst Island 48 (Summer) 918 (Summer) 1850 (Summer) 46 (Summer) Pulau Semau 10 (Transitional) 1162 (Summer) 518 (Summer) 26 (Transitional) West Timor 20 (Summer) 761 (Summer) 639 (Summer) 27 (Summer) East Timor 24 (Summer) 857 (Summer) 1994 (Summer) 16 (Summer) Pulau Dana 32 (Transitional) 283 (Transitional) 2054 (Summer) 177 (Winter) Raijua 8 (Transitional) 1136 (Summer) 322 (Winter) 45 (Winter)

Alor 8 (Summer) 1362 (Summer) 241 (Summer) 18 (Summer)

Wetar 20 (Summer) 839 (Summer) 567 (Summer) 26 (Summer)

Liran 4 (Summer) 1797 (Summer) 131 (Summer) 23 (Summer)

Pulau Kisar 26 (Summer) 749 (Summer) 1180 (Summer) 86 (Summer) Romang 12 (Summer) 1332 (Summer) 1547 (Summer) 54 (Transitional) Nyata 2 (Transitional) 2060 (Transitional) 662 (Transitional) 46 (Transitional)

Dai 2 (Summer) 1183 (Summer) 162 (Summer) 12 (Summer)

Papua 6 (Summer) 2010 (Summer) 328 (Summer) 5 (Summer)

Kepulauan Aru 2 (Summer) 1861 (Summer) 118 (Summer) 3 (Summer) Christmas

Island 18 (Winter) 1460 (Winter) 1478 (Winter) 37 (Winter)

The minimum predicted time oil could be sighted on the shoreline was 122 hours (or 5.1 days) at Cartier Island under winter, 249 hours (or 10.4 days) under transitional conditions and 315 hours (13.1 days) under summer.

4.4

PRIORITIES

In the event of a spill, PTTEP AA in accordance with AMSA guidance, will be guided by the following priorities:

 human health and safety;  habitat and cultural resources;

 rare and/or endangered flora and fauna;  commercial resources; and

 amenities.

The EP assessed all locations and sensitivities that could be impacted in the event of a spill, with consideration of the maximum average loads and minimum times to contact.

Many locations will potentially be impacted in the event of a loss of well control. The following three environmentally sensitive locations have been identified an assigned as priority locations for protection in the event of a spill based on the sensitivities, loads ashore and times to contact. These are:

 Ashmore Reef;

 Cartier Island; and  Hibernia Reef.

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5

SPILL RESPONSE STRATEGY

5.1

OVERVIEW OF RESPONSE PLANNING

This section details the priorities, equipment, resources and response strategies that would be deployed in the event of a spill during Montara PDW activities.

Response strategies have been developed on the basis of predictive modelling and experience from the Montara drilling incident in 2009. As Section 4.3 detailed, the single case trajectory provides a basis for planning a response strategy as it demonstrates the characteristics of the hydrocarbons. The modelling illustrates how the subsea release produces spot slicks of oil with a concentration of greater than 10 g/m2_{for the first seven days. The characteristics of the oil to form}

spot slicks is accounted to the high release rate estimated for a well blowout scenario. The response strategies have therefore been developed to target these areas and reduce the volume of oil that could potentially travel and contact shorelines.

After seven days, the frequency of spot slicks of greater than 10 g/m2_{are limited and it is only the}

area in close proximity to the release site that features unweathered crude with sea surface exposures of greater than 10 g/m2_{. This has been utilised to determine the extent of response}

strategies required and enables the resources for each strategy to be evaluated.

As was undertaken during the Montara incident in 2009, the oil spill modelling outputs may require reassessment, using revised real-time modelling and observation of the spill. In a spill event, the spill trajectory, size, spill event time/season may result in a different impact than the scenarios provided in this document. Any such re-work would be incorporated into an IAP as detailed in section 3.4.

The response strategies that may be implemented are dependent on the volume of hydrocarbon, location of the spill event, environmental conditions at the time of the spill, and sensitivities in the ZPI.

There are eight potential response options:

1. Monitor and Evaluate: this is applicable to all spill scenarios. In the event that a surface spill does not threaten any environmental sensitivity, it may be the only strategy that is deployed. 2. Dispersant Application: samples of Montara hydrocarbons have undergone weathering and

dispersant testing. During a Tier 3 spill incident, dispersant amenability testing and a NEBA assessment will be undertaken to confirm the applicability of the strategy. This strategy is likely to be the primary strategy for the reduction of hydrocarbons reaching environmental sensitivities.

3. In-situ Burning: this strategy may be considered in the event of a loss of well control if there are high concentrations of surface oil on the sea surface and the environmental conditions are suitable.

4. Containment and Recovery: this strategy may be useful to recover any persistent weathered residues floating on the sea surface and prevent them from reaching shore providing sea states permit. Weathering assessment of Montara crude oil samples have been undertaken to determine the properties of the weathered product, in addition to the observations of weathering during the Montara incident in 2009, these are detailed in the EP.

5. Protection and Deflection: this strategy will only be deployed when surface hydrocarbons threaten environmental sensitivities due to the failure or inability to deploy dispersant application and/or containment and recovery techniques. A NEBA assessment will determine whether deployment of the strategy will have an overall environmental benefit to protecting shorelines which may be sensitive to the protection and deflection activities.

6. Shoreline Clean-up: this is a strategy of ‗last resort‘ and will only be deployed in the event of surface hydrocarbons impacting shorelines. A NEBA assessment will determine whether deployment of the strategy will have an overall benefit to shorelines (which may be sensitive to shoreline clean-up techniques).

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Technical#810827 Rev 4 Page 37 of 169 7. Oiled Wildlife Response: this strategy will be considered for deployment where surveillance

activities identify marine fauna that may be impacted by the spill.

8. Waste Management: this strategy will be required to support all active response strategies. For all tiers, source control is undertaken to ensure no further release of hydrocarbons to the marine environment.

The process in which these response strategies will be considered is illustrated in Figure 5-2. These strategies can be implemented concurrently depending on the location and characteristics of the spill. The viability of implementing response strategies will be dependent on a number of factors including but not limited to environmental conditions, resources available and distance from sensitivities. Development of an Incident Action Plan (section 3.4) will assess these various factors. A Net Environmental Benefit Assessment (as detailed in section 5.10) will be undertaken frequently to determine which response strategies will provide a net environmental benefit to the environmentally sensitive locations that may be impacted.

All viable strategies will be implemented until their performance objectives are satisfied.

Figure 5-1 Basic Response Strategy Process

5.2

MONITOR AND EVALUATE

The ongoing monitoring and evaluation of the oil spill is essential to maintaining situational awareness. Situational awareness based on the likely fate and trajectory of the spilt oil is fundamental to putting in place an oil spill response that will be efficient and effective.

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Technical#810827 Rev 4 Page 38 of 169 Based on the ZPI, PTTEP AA will use a variety of methods to gain and maintain situational awareness of the spill. Operational monitoring may also commence at this point if triggered (refer Section 7).

Monitoring and evaluation will be undertaken for any tier spill to sea during Montara PDW activities in order to monitor the location of the spill and state of natural weathering.

There are four key sources for monitoring a spill:  real time oil spill trajectory modelling (OSTM);  satellite tracking buoys;

 observations from a vessel; and  aerial surveillance.

Real time oil spill trajectory modelling will be used to estimate the likely movement and behaviour of the spill and will be verified by field observations. The oil spill trajectory modelling will be sourced from within 24 hours using their 24/7 emergency capability and the location of the slick predicted by oil spill trajectory modelling will be verified by field observations. Preliminary estimations using visual observations from the field and manual calculations will be available within approximately 3 hrs to inform the mobilisation of equipment and resources in preparation for potential response strategies.

Satellite tracking buoys are also available in the field (two on the MODU support vessel) and will be deployed in the event of a Tier 2 or 3 spill. One buoy will be deployed from the support vessel at the leading edge of the spill plume within 3 hours of the spill event in order to:

 monitor movement of surface oil; and  qualify and assist surveillance monitoring. To access tracker buoy data go to website:

Resources available to respond to a spill requiring monitoring and evaluation (Tier 1, 2 and 3 spills) are given in Table 5-1 with the minimum standard for resource mobilisation time post activation by the EMT.

Vessel surveillance will involve visual monitoring from the MODU and from vessels of opportunity, which may be engaged immediately in the event of a spill. Vessel surveillance may assist in determining if additional response actions are required.

Vessel surveillance will incorporate Operational monitoring studies as outlined in Section 6; this will involve various monitoring and sampling methodologies of water to determine the extent of surf