APLNG - Spring Gully Coal Seam Gas Water Management Plan...3.1.3 Australia Pacific LNG Project EIS Local Needs Analysis 25 ... Document Custodian is IG-Operations-APLNG-HSE Origin

Spring Gully North-West and North-East Project – Preliminary Documentation REPORT

Appendix 10: Spring Gully Coal Seam Gas Water Management Plan (Spring Gully CWMP) (CDN/ID 12369206)

Management Plan QLD 8200 ENV PLN

CDN/ID 12369206

THE THREE

WHATS What can go wrong? What could cause it to go wrong? What can I do to prevent it?

Review due: 10/11/2020

For internal Origin use and distribution only. Subject to employee confidentiality obligations.

Once printed, this is an uncontrolled document unless issued and stamped Controlled Copy or issued under a transmittal.

Integrated Gas

SPRING GULLY COAL SEAM GAS WATER MANAGEMENT PLAN Australia Pacific LNG Upstream Phase 1 This coal seam gas (CSG) water management plan describes the strategy for managing CSG water, treated CSG water and brine produced in the Spring Gully development area. It also describes the environmental values of the development area and the objectives to be met to ensure that potential environmental impacts from CSG water and brine management are adequately controlled.

Review record

Rev Date Reason for issue Originator Checked QA/Eng Approved

0 29/06/2011 Issued to DERM SM DC BC

1 21/10/2011 Issued to DERM in response to RFI

VC JM SM

2 16/01/2012 Issued for Approval TA JM SM

3 22/03/2013 Issued for use K. Presley J. Mitchell D. Carberry J. Long

4 09/01/2015 Draft issue as proposed CWMP for DEHP pre-lodgement

A. Lane K. Presley J. Mitchell M. Renfree

5 27/11/2015 Brine Management Plan updated

Profiles updated T. Hill J. Murray V. Cavanough S. Fletcher

5A 08/02/2017 Issued for EPBC Referral V. Cavanough J. Long

M. Renfree V. Cavanough S. Fletcher

6 08/02/2017 Issued for Use - - - S. Fletcher

6A 10/11/2017 Issued for Response to EPBC Referral 2017/7881 IESC Advice

V. Cavanough J. Long

S. Dale

6B 22/11/2017 Updated Water Balance Modelling

V. Cavanough J. Long -

7 22/11/2017 Issued for Use S. Fletcher

Spring Gully Coal Seam Gas Water Management Plan CDN/ID 12369206

Released on 22/11/2017 - Revision 7 - Status Issued for Use Document Custodian is IG-Operations-APLNG-HSE

Origin Energy Upstream Operator Pty Ltd ABN 67 105 423 532 Page 2 of 94 Once printed, this is an uncontrolled document unless issued and stamped Controlled Copy or issued under a transmittal. Based on template: AUS 1000 IMT TMP 4881989_Revision 2_IFU_03/03/2016_IG-SystemsInfo-DocRecordsMgt

Table of contents

Executive Summary 7

Terms, Abbreviations and Definitions 10

1. Introduction 13

1.1 Background 13 1.2 Objectives of the CWMP 13 1.3 Scope of the CWMP 14

2. Resource Profile 18

2.1 Background 18 2.2 Produced CSG water 18

2.2.1 CSG water production profile 18 2.2.2 CSG water quality 19

2.3 Treated CSG Water 20 2.3.1 Treated CSG water production profile 20 2.3.2 Treated CSG water quality 21

2.4 Brine and Salt 23 2.4.1 Brine production profile 23 2.4.2 Brine quality 23

3. CSG Water Management Strategy 24

3.1 Strategy Drivers 24 3.1.1 Australia Pacific LNG’s CSG water management philosophy 24 3.1.2 History and Current Operations of the SGDA 24 3.1.3 Australia Pacific LNG Project EIS Local Needs Analysis 25

3.2 Re-evaluation of the SGDA CSG Water Management Strategy 26 3.2.1 Irrigation Scheme (Agricultural Use) 27 3.2.2 Aquifer injection 28 3.2.3 Release to Surface Waters 28

3.3 Transition Stage and Future SGDA CSG Water Management Strategy 28 3.4 SGDA (Site) Water Balance Model 29 3.5 CSG water management for E&A programs 33

4. Brine and Salt Management Strategy 33

4.1 Option evaluation and assessment criteria 34 4.1.1 Selective Salt Recovery (SSR) 34

4.2 Long Term Management Strategy 36

5. CSG Water, Brine and Salt Management Scheme 36

5.1 Untreated CSG water management scheme 37 5.1.1 CSG water gathering network 37 5.1.2 CSG water storage 37 5.1.3 Untreated CSG water use 38

5.2 Treated CSG water management scheme 38 5.2.1 CSG Water Treatment 38 5.2.2 Treated CSG water use 42

5.3 Brine and salt management scheme (Encapsulation) 44 5.3.1 Brine ponds 45 5.3.2 Regional Brine Aggregation Pipelines 45 5.3.3 Brine Crystalliser 46 5.3.4 Salt Encapsulation in a RWF 46

6. Existing Environment 46

6.1 Climate 46 6.2 Land 47




6.2.1 Topography and geomorphology 47 6.2.2 Geology and soils 47 6.2.3 Land use 48

6.3 Groundwater 48 6.3.1 Hydrogeology 48 6.3.2 Groundwater quality 49 6.3.3 Groundwater use 49 6.3.4 Groundwater – surface water interaction 49 6.3.5 Groundwater dependent ecosystems 49

6.4 Surface water 52 6.4.1 Hydrology 53 6.4.2 Surface water quality 55 6.4.3 Surface water use 55 6.4.4 Aquatic habitat 55 6.4.5 Aquatic ecology 55 6.4.6 Environmentally Sensitive Areas 55 6.4.7 Matters of National Environmental Significance 56

7. Environmental Values and Water Quality Objectives 56

8. Risks, Potential Impacts and Management 57

8.1 Risk assessment process 58 8.2 Untreated CSG water management scheme 59

8.2.1 CSG water gathering network 59 8.2.2 CSG water storage 59 8.2.3 Use of untreated CSG water 60

8.3 Treated CSG water management scheme 65 8.3.1 Project activities 65 8.3.2 Irrigation and livestock watering 65 8.3.3 Aquifer injection 65 8.3.4 River release 65

8.4 Brine and salt management scheme 71 8.4.1 Brine ponds 71 8.4.2 Brine aggregation pipelines 71 8.4.3 Brine crystalliser 71 8.4.4 Salt encapsulation facility 71

8.5 Incident and emergency response 74

9. Management Criteria 74

10. Monitoring 79

10.1 Overview 79 10.2 Operations Monitoring 80

10.2.1 Dam Monitoring 80 10.2.2 CSG Quality Monitoring 81 10.2.3 Environmental Monitoring 82 10.2.4 Pond and Shallow Groundwater Monitoring Plan 82 10.2.5 Deep Groundwater Monitoring Plan 82 10.2.6 Soils Monitoring Program 82

11. Management Systems and Records 83

11.1 HSEMS 83 11.2 Operations Environmental Management Plan 85 11.3 Project Delivery Process 85 11.4 Complaints and Customer Satisfaction System 85 11.5 Environmental Data Management System 86 11.6 OpenText 86 11.7 Origin Collective Intelligence System 86

11.7.1 Incidents 86 11.8 Risk Registers 86




11.9 Learning Management System 86 11.10 Enterprise Asset Management System 86 11.11 ATLAS 86

12. Reporting 87

12.1 Routine 87 12.1.1 Monitoring Results 87 12.1.2 Audits and Reviews 87 12.1.3 Compliance 87

12.2 Non-routine 87 12.2.1 Monitoring Results 87 12.2.2 Incident and Emergency Events 88

13. References 88

14. Document information and history 90

Table of figures

Figure 1-1: SGDA (Spring Gully and Injune EAs) Location Plan 16

Figure 1-2: Australia Pacific LNG Project Locality Plan 17

Figure 2-1: Predicted Rate of CSG Water Production 18

Figure 2-3: Predicted Rate of Treated CSG Water Production 21

Figure 2-4: Predicted Rate of Brine Production and Accumulated Salt Mass 23

Figure 3-1: Detailed Analysis – Spring Gully Peak Production CSG Water Profile (2017-2020) 30

Figure 3-2: Spring Gully Additional Irrigation Demand During Peak Production 31

Figure 3-3: Spring Gully Existing Irrigation Demand During Peak Production 31

Figure 3-4: 350 ML Storage Dam Volumes and Evaporation Rates During Peak Production 32

Figure 3-5: Spring Gully Aquifer Injection Rates 32

Figure 4-1: Option Identification and Evaluation Process 34

Figure 4-2: Salt Encapsulation SchematicRanking of assessed brine and salt management options 36

Figure 4-3: Brine Management Strategy 36

Figure 5-1: Simplified Process Flow Diagram of Treatment Steps at the WTF and PIP (Transition Stage and Future water strategy) 41

Figure 5-2: PIP Process Flow Diagram 43

Figure 5-3: Overview of Processes and Operations for RWF 45

Figure 6-1: Regional Climate 46

Figure 6-2: Eurombah Creek at Brookfield – Daily Flow Duration Curve 54

Figure 6-3: Time Series of Daily Flow, Rainfall and Releases 54

Figure 8-1: Risk Assessment Process 58

Figure 8-2: Risk Matrix 59

Figure 8-3: Crisis and Emergency Response Framework 74

Figure 10-1: SG CWMP Monitoring Programs 79

Figure 11-1: Elements of the HSEMS and Continuous Improvement 84

Figure 11-2: HSE Framework 84




List of tables

Table 1-1: Summary Requirements of Legislation and Approval Conditions 15

Table 2-1: CSG Water Quality 19

Table 2-2: Treated CSG Water Quality 21

Table 2-3: Brine Quality 23

Table 3-1: Categories of CSG Water Management Option 26

Table 3-2: CSG Water Management Strategies for Australia Pacific LNG EIS gas fields 26

Table 3-3: SGDA Transition Stage and Future CSG Water Management Strategy (Excluding Brine) 28

Table 3-4: Option Evaluation for SGDA E&A CSG Water Management 33

Table 5-1: CSG Water Storage Feed Ponds in Operation 38

Table 5-2: Summary of Approvals Governing the Use of Treated CSG Water in the SGDA 42

Table 5-3: Location of Injection Bores and Monitoring Bores 43

Table 5-4: Aquifer Injection PLC Set Points 44

Table 6-1: Land Use in the SGDA 48

Table 6-2: Hydrostratigraphic Sequence 51

Table 6-3: Precipice Sandstone Groundwater Quality 52

Table 6-4: Landholder Bores and Water Uses 52

Table 6-5: Estimated Annual Flows in Eurombah Creek at the Eastern Gully Confluence 53

Table 7-1: Environmental Values of Water 56

Table 8-1: Risks and Controls for the Untreated CSG Water Management Scheme 61

Table 8-2: Risks and Controls for the Treated CSG Water Management Scheme 67

Table 8-3: Risks and Controls for the Brine and Salt Management Scheme – Current Infrastructure 72

Table 9-1: Management Criteria of the Spring Gully CWMP (applicable to the Spring Gully and Injune EAs) 76

Table 10-1: Dam Monitoring Requirements 80

List of appendices

Appendix A Origin Energy Document References 91

Appendix B Spring Gully CSG Water Quality Monitoring Plan (CDN 8600569) 93

Appendix C Spring Gully Receiving Environment Monitoring Program – Eurombah Creek (CDN 8600568) 94




Release Notice

This document is available through OpenText. The responsibility for ensuring that printed copies remain valid rests with the user. Once printed, this is an uncontrolled document unless issued and stamped Controlled Copy.

Document Conventions

The following terms in this document apply:

Will, shall or must indicate a mandatory course of action

Should indicates a recommended course of action

May or can indicate a possible course of action.

Document Custodian

The custodian of this document is the Environment Manager, Production Operations. The custodian is responsible for maintaining and controlling changes (additions and modifications) to this document and ensuring the stakeholders validate any changes made to this document.

Deviations from Document

Any deviation from this document must be approved by the Environment Manager, Production Operations.




Executive Summary

This coal seam gas (CSG) water management plan (CWMP) describes how CSG water produced in the Spring Gully Development Area (SGDA) is managed safely and in a manner that maximises its beneficial use whilst ensuring the protection of environmental values (EVs) and balancing social and economic factors.

Location

The Spring Gully development covers an area of approximately 256,000 ha in south central Queensland between the towns of Roma, Injune and Taroom. The development area lies within the Upper Dawson River catchment of the Fitzroy Basin and is predominantly drained by Eurombah Creek and its tributaries. Land use within the development area is dominated by livestock grazing. Geologically, the development area lies within the Surat Basin, with CSG activities targeting the Bandanna and Reids Dome Formations.

CSG Water Management Strategy

Full-scale production of CSG in the SGDA commenced in 2005 with current CSG activities authorised by the Spring Gully Environmental Authority (EA) (EPPG00885313) and the Injune EA (EPPG00302013), issued by the Queensland Government Department of Environment and Heritage Protection (DEHP).

The original CSG water management infrastructure of the SGDA was designed and constructed in accordance with the regulation of the time and initially comprised a series of storage ponds used to store CSG water. To support future beneficial uses of CSG water, in 2007, Australia Pacific LNG constructed the Spring Gully Water Treatment Facility (WTF). Treated CSG water from the WTF was initially wholly released to Eurombah Creek in accordance with the Spring Gully EA. Brine generated at the WTF was stored in brine storage ponds.

The WTF represented Australia Pacific LNG’s first significant WTF and provided the opportunity to assess the viability of a variety of treated CSG water management options1 including irrigation and aquifer injection via trial schemes as well as brine management options via pilot studies. These investments have helped to guide the development of the following CSG water management portfolio of the development area:

Beneficial use of CSG water for project activities (including construction, dust suppression and landscaping and revegetation) in accordance with the General Beneficial Use Approval Associated Water (including coal seam gas water) (DEHP 2014a) (the General BUA);

1 Refer to Version 4 of this CWMP version for summation of the options evaluation.




Beneficial use of treated CSG water from the WTF for:

Project construction and operational activities in accordance with the General BUA;

Irrigation in accordance with the General Beneficial Use Approval Irrigation of Associated Water (including coal seam gas water) (DEHP 2014b) (Irrigation General BUA);

Stock watering in accordance with the General BUA; and

Full-scale aquifer injection in accordance with the Spring Gully EA;

Intermittent contingency release of treated CSG water to Eurombah Creek when the inherent variability of irrigation demand means that a proportion of the treated CSG water cannot be beneficially used in accordance with the Spring Gully EA;

Storage and concentration of brine in ponds by solar evaporation; and

Crystallisation of concentrated brine to salt suitable for encapsulation in a regulated waste facility, forecast for implementation approximately 20 years from now.

It is currently predicted that CSG water production in the SGDA will peak through the period between 2017 and 2021.

To ensure that the CSG water strategy of the SGDA continues to present the most appropriate means of managing the quantities and qualities of the CSG water produced from SGDA, the effectiveness of existing options has been re-evaluated along with the potential performance of a range of alternatives. In accordance with the requirements of the CSG Water Management Policy (DEHP 2012), this process preferentially considered options defined as Priority 1 by the policy.

This re-evaluation has identified the requirement to install additional beneficial use capacity to manage the forecast production associated with the development of the North West and North East (NW/NE) areas of the SGDA to remove the requirement for contingency discharge to Eurombah Creek.

Consequently, the operation of the Spring Gully WTF is currently in a transition stage to achieve 100% beneficial use of treated CSG water by the time the NW/NE areas of the SGDA are commissioned. The transition stage is defined as the period from Q4 2017 until the first well originating within the NW/NE area is bought online. During this period river discharge will continue to support the existing beneficial use schemes whist additional beneficial use capacity is constructed. This additional beneficial use capacity will be provided by increasing the current performance of the aquifer injection scheme (in accordance with the existing EA) and constructing a centre pivot irrigation scheme to increase irrigation demand.

The future CSG water management portfolio will therefore rely on:

An Expanded Irrigation Scheme (comprising 285 ha Pongamia and ~136 ha of cropping), operated in accordance with beneficial use approvals; and

Full-scale aquifer injection in accordance with the Spring Gully EA.

The existing beneficial use of CSG water (untreated and treated) for project activities will continue subject to supply and demand but does not form part of water balance modelling.

Brine and Salt Management Strategy

The long term preferred brine management strategy for the SGDA involves initial storage of brine in approved ponds designed, constructed and operated in accordance with the Spring Gully EA and the Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2013). Solid salts resulting from brine evaporation over time will be finally disposed of in an licensed regulated waste facility prior to the end of the life of the Australia Pacific LNG Project.

The Brine Investigation Report (BIR) (Q-LNG01-95-RP-1763) describes outcomes of the brine studies to date, presenting the corresponding screening and option evaluation including risk assessment, and provides evidence to support the preferred option of Encapsulation.

Risk Assessment

Australia Pacific LNG has conducted an environmental risk assessment for each component of the strategies for CSG water and brine management. For each identified risk, existing controls have been identified and consequence and likelihood ratings combined to derive a risk level. The risk assessment found that existing controls are successful in mitigating all environmental risks to acceptable levels for the existing operational brine infrastructure.




To evaluate the performance of the strategies and in turn, to support continual improvement of their operation, Australia Pacific LNG has developed a series of management criteria, each of which includes:

A management objective for protecting EVs from the potential impacts of CSG water or brine management activity;

A series of tasks that will ensure that the objective can be achieved;

Specific indicators against which the performance of CSG water management can be measured, assessed and audited in an objective and repeatable manner; and

A target for CSG water or brine management.

Australia Pacific LNG will submit annual returns to DEHP showing how the conditions of the Spring Gully EA have been met and evaluating performance against the management criteria. Should a criterion not be met, Australia Pacific LNG will investigate the potential causes and where appropriate, identify and implement measures to ensure it can be met in future. Any incidents will be managed in accordance with the LNG Environmental Incident Procedure (CDN 3675694).




Terms, Abbreviations and Definitions

Term/Abbreviation Definition

ADWG Australian Drinking Water Guidelines (NHMRC 2011)

AEP Annual exceedance probability

AIMP Aquifer Injection Management Plan

ANZECC Guideline Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC and ARMCANZ 2000)

ATP Authority to prospect

Australia Pacific LNG Project EIS

Australia Pacific LNG Project Environmental Impact Statement (Australia Pacific LNG 2010)

AWBM Australian Water Balance Model

BIR Brine Investigation Report (Q-LNG01-95-RP-1763) summarising the brine and salt management options investigated; the methodology for evaluation and selection of the preferred brine and salt management options; and the recommended brine and salt management strategy to be adopted for the Australia Pacific LNG project.

BoM Australian Government Bureau of Meteorology

Brine DEHP (2012) define ‘brine’ as saline water with a concentration of total dissolved solids exceeding 40,000 mg/L. For the purpose of this CWMP, all saline effluent generated at the WTF is referred to as brine, regardless of total dissolved solids concentration.

BUA Beneficial Use Approval

CDN Controlled Document Number

CSG Coal Seam Gas

CSG water Water produced from a CSG well to enable gas production

CWMP Coal Seam Gas water management plan

DEHP Queensland Government Department of Environment and Heritage Protection.

Prior to April 2012, the functions of DEHP were conducted by the Department of Environment and Resource Management (DERM).

DF Disc Filtration

DNRM Queensland Government Department of Natural Resources and Mines

DSA Design Storage Allowance

EA Environmental Authority

EAMS Enterprise Asset Management System

E&A Exploration and Appraisal

ESA Environmentally Sensitive Area

EsDAT Environment data management system

EP Act Environmental Protection Act 1994 (Qld)

EPBC Act Environment Protection and Biodiversity Conservation Act 1999 (Cth)

EPP Water Environmental Protection (Water) Policy 2009 (Qld)

EV Environmental value

GAB Great Artesian Basin

General BUA General Beneficial Use Approval Associated Water (including coal seam gas water) (DEHP 2014a)

GoldSim GoldSim Pro (water balancing modelling software)





HDPE High-density polyethylene

HEV High Ecological Value

HSE Health, Safety and Environment

HSEMS Health, Safety and Environment Management System

Injectate Degassed treated CSG water to be injected

Injune EA Environmental Authority EPPG00302013

Irrigation General BUA

General Beneficial Use Approval Irrigation of Associated Water (including coal seam gas water) (DEHP 2014b)

LNG Liquefied Natural Gas

MF Membrane Filtration

ML/d Mega Litre per Day

NATA National Association of Testing Authorities

NW/NE Petroleum Leases (PL) 414, 415, 416, 417 and the northern section of PL 418

O&M Operations and Maintenance

OCIS Origin Collective Intelligence System

Origin Energy Origin Energy Upstream Operator Pty Ltd

PDP Project Delivery Process

PIP Permeate Injection Plant

PL Petroleum Lease

PLC Programmable Logic Controller

Project activities Includes construction activities (such as drilling, well completions and work-overs, hydraulic fracturing, facilities construction, hydro-testing of gathering networks), dust suppression and landscaping and rehabilitation.

QLUMP Queensland Land Use Mapping Program

REMP Receiving Environment Monitoring Program

RO Reverse Osmosis

RPEQ Registered Professional Engineer of Queensland

RWF Regulated Waste Facility

SCADA Supervisory Control and Data Acquisition

SGDA The CSG development area operated by Origin Energy and administered by the Spring Gully EA (EPPG00885313) and Injune EA (EPPG00302013).

Spring Gully EA Environmental Authority EPPG00885313

Spring Gully IMP Spring Gully Aquifer Injection Management Plan (Q-8200-95-MP-1008)

SSR Selective Salt Recovery

TDS Total Dissolved Solids

TOWL Top Operating Water Level

Transition Stage The period from Q4 2017 to the first well online originating within the NW/NE area during which time the existing water portfolio is optimised.

Treated CSG water Water produced from a CSG well which has undergone treatment prior to end use

Untreated CSG water Water produced from a CSG well which has not undergone treatment prior to end use

UV Ultraviolet





UWIR Underground Water Impact Report for the Surat Cumulative Management Area (QWC 2012)

WQMP Water Quality Monitoring Plan

WTF Water Treatment Facility

WQO Water Quality Objective




1. Introduction

1.1 Background

The Spring Gully Development Area (SGDA) is a coal seam gas (CSG) field covering approximately 256,000 ha of land in south central Queensland and comprising petroleum leases (PLs) 195, 200, 203, 204, 268, 414, 415, 416, 417, 418 and 419, as well as authority to prospect (ATP) 592, as shown in Figure 1-1. The closest towns to the development area are Roma, 50 km to the southwest, Injune, 40 km to the west and Taroom, 40 km to the east.

Origin Energy Upstream Operator Pty Ltd (Origin Energy) is the appointed upstream operator of the SGDA and delivers this role on behalf of Australia Pacific LNG Pty Limited, a joint venture between Origin Energy, ConocoPhillips and Sinopec Group.

Full-scale production of CSG in the SGDA commenced in 2005 and current CSG activities are authorised by the following two (2) environmental authorities (EAs), issued by the Queensland Government Department of Environment and Heritage Protection (DEHP):

For CSG activities in all PLs of the SGDA, EA EPPG00885313 (the Spring Gully EA); and

For CSG activities in ATP 592, EA EPPG00302013 (the Injune EA).

Australia Pacific LNG’s current operation of the SGDA is integrated with that of the Australia Pacific LNG Project, a CSG to liquefied natural gas (LNG) project that consists of the following principal components:

Production of CSG in development areas (including Spring Gully) located in the Queensland local government areas of Maranoa, Toowoomba and Western Downs;

Construction and operation of a 450 km gas transmission pipeline to transport CSG from the development areas to an LNG production facility on Curtis Island, near Gladstone on the central Queensland coast; and

Construction and operation of the LNG production facility.

1.2 Objectives of the CWMP

The process of producing gas from CSG wells produces water (herein termed CSG water) which will be managed in accordance with this CSG Water Management Plan (CWMP).

This CWMP has the overarching objective of maximising beneficial uses of CSG water in order to deliver sustainable outcomes that protect environmental values (EVs) whilst balancing social and economic considerations. This objective is supported by the following series of aims:

To ensure that the implemented options of managing CSG water continue to reflect the most appropriate solution for the development area, providing flexibility to successfully manage a range of variables that include:

The rates and quality of CSG water production;

The locations and volumes of CSG water demand;

Advances in technology;

The outcomes of ongoing monitoring of EVs;

Understanding of social constraints; and

Evolving regulatory requirements.

To document how the potential environmental risks of CSG water management are and will be effectively controlled; and

To establish the means to regularly assess the performance of CSG water management against a set of defined criteria, thereby providing the mechanism for continually improving the best practice management of CSG water.

This CWMP has been prepared in accordance with the following documents:

The Environmental Protection Act 1994 (Qld) (the EP Act), specifically Section 126;

The Spring Gully EA; and

The 2012 CSG Water Management Policy, published by DEHP.




Table 1-1 lists the primary requirements from the above documents relevant to CSG water management and indicates the section of this CWMP in which each requirement is met.

Revision 7 of this CWMP has been prepared to respond to advice given to the decision maker on the NW/NE referral (EPBC 2017/7881) by the Independent Expert Scientific Community, including updated water balance modelling.

Note: A number of previous reviews of this CWMP have been undertaken to support applications for the CSG water management strategy. The most recent CWMP revision history is provided below for reference.

February 2017 (Version 6) – Revised profiles to assess impacts of expanding into the Spring Gully ‘northern development area’ (I.e. PLs 414, 415, 416, 417 and the northern section of PL418) to support the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) Referral application.

December 2015 (Version 5) – Update of the imbedded Brine and Salt Management Plan based on the submission to DEHP of the BIR (Q-LNG01-95-RP-1763), including update of the water and salt profiles, and general administrative changes.

January 2014 – February 2015 (Version 4) – Update of the CWMP to support an EA amendment application for continued release (up to March 2020) of treated CSG water to Eurombah Creek (refer to Q-8200-15-EA-1063).

1.3 Scope of the CWMP

This CWMP describes all those activities associated with the management of CSG water in the SGDA once that CSG water has been recovered to the ground surface. It considers the management of CSG water over the lifetime of the SGDA and will be updated as required in order to continue to ensure that the most appropriate CSG water management approach is in place.

The following activities are out of scope for this CWMP:

Management of stormwater – addressed in the project’s Construction Environmental Management Plans (Q-LNG01-15-MP-1005, Q-LNG01-15-MP-0144);

Management of wastewater from camps and processing facilities;

Management of hydrostatic test water – addressed in the Land Release Management Plan (CDN 11970260); and

Hydraulic fracture stimulation, noting that where Australia Pacific LNG plans to undertake hydraulic fracturing, this will be undertaken in accordance with Schedule J of the Spring Gully EA.

A variety of management and operational documents support the implementation of this CWMP and are listed in Appendix A. Documentation attached to this CWMP include:

Spring Gully Water Quality Monitoring Program (CDN 8600568), refer to Appendix B; and

Spring Gully Receiving Environment Monitoring Program - Eurombah Creek (CDN 8600568), refer to Appendix C.




Table 1-1: Summary Requirements of Legislation and Approval Conditions

Requirement Section Reference

Section 126 of the EP Act

The quantity of produced water the applicant reasonably expects will be generated in connection with carrying out each relevant activity.

Section 2

The flow rate at which the applicant reasonable expects water will be generated. Section 2

The quality of the water, including changes in the water quality that the applicant reasonably expects will happen while each relevant activity is carried out.

Section 2

The proposed management of water including use, treatment, storage or disposal. Section 4.1

The measurable criteria (the management criteria) against which the applicant will monitor and assess the effectiveness of water management including:

The quantity and quality of the water used, treated, stored or disposed of.

Protection of environmental values affected by each relevant activity.

The disposal of waste, including, for example, salt.

Section 8.5

The action proposed to be taken if any of the management criteria are not complied with, to ensure the criteria will be able to be satisfied in the future.

Section 8.5

The proposed management of the water cannot provide for using a CSG evaporation dam in connection with carrying out a relevant CSG activity unless:

(a) the application includes an evaluation of:

(i) best practice environmental management for managing the CSG water; and

(ii) alternative ways for managing the water; and

(b) the evaluation shows there is no feasible alternative to a CSG evaporation dam for managing the water.

Not applicable

Conditions of the Spring Gully EA

(B26) The holder of this authority must prepare and submit a Discharge to Waters Release Strategy on treated coal seam gas water to the Administering Authority within 6 months upon the granting of this authority should the holder of this authority intend to continue the discharge of treated coal seam gas water to Eurombah Creek.

Spring Gully Discharge to

Waters Release Strategy (Q-8220-

15-MP-018) submitted to DEHP in October 2014.

Not further considered in this

CWMP (B28) As part of the Associated Water Management Plan (AWMP) the holder of this authority must develop and implement an on-going Release Reduction Strategy to maximise associated water re-use and to minimise any release to waters from the Reverse Osmosis Plant located on PL 195. The strategy must address the following matters:

Section 3

(Superseded Release Reduction Strategy (Q-8200-

95-EA-001))

Implementation of re-use measures to achieve maximum use of the water.

Specific targets for achieving increased re-use of treated and untreated associated water.

A market analysis at least every three (3) years to identify existing and future opportunities for water re-use.

On-going review of emerging technologies and/or re-use options that could achieve significant reductions in mass loads of contaminants released to the environment.

Investigation of the feasibility of alternative options, practices and procedures to further minimise the volume and concentration of contaminants released to waters.

Programs to implement feasible options to achieve increased water re-use and reduction in contaminant loads, including actions and timeframes for completion.




Figure 1-1: SGDA (Spring Gully and Injune EAs) Location Plan




Figure 1-2: Australia Pacific LNG Project Locality Plan




2. Resource Profile

2.1 Background

To predict the rate at which CSG water will be produced from a given CSG well, Australia Pacific LNG uses numerical models to simulate reservoir conditions in the coal seam and its surrounding geology. As field data is collected, these models are regularly updated in order to allow necessary model assumptions to be progressively refined.

This CWMP has used the numerical model’s best technical estimate of CSG water production as the basis for evaluating and selecting options for the management of CSG water, treated CSG water and brine. Other model parameters, including for different technical and reservoir assumptions, are used as sensitivity tests. The varied characteristics of the coal seam and other sub-surface structures, as well as the actual development program, performance and availability of surface infrastructure, may mean that actual CSG water production deviates from the predicted trend.

In order to maximise the opportunities for its beneficial use, CSG water produced in the SGDA is currently treated using Reverse Osmosis (RO) desalination, a technology that generates two (2) products, treated CSG water and brine. The rate at which each product is produced depends on three (3) factors; the rate of CSG water production requiring management, the rate at which CSG water is processed through the RO unit, and the recovery rate of the RO unit (i.e. the percentage of the CSG water entering the RO unit that becomes treated CSG water).

The CSG water production profile forms the basis for the evaluation and selection of strategies for the management of CSG water, treated CSG water and brine (as outlined in Sections 3 and 4), as well as for the development of the associated infrastructure schemes (see Section 5).

2.2 Produced CSG water

2.2.1 CSG water production profile

Figure 2-1 presents the best technical model prediction of forecast CSG water production from CSG production wells in the SGDA until circa 2065, inclusive of:

Existing operational areas (PL 195, 200, 204 and 268)

Bandanna formation contributions displayed by tenure

Reids Dome.

Figure 2-1: Predicted Rate of CSG Water Production




Figure 2-1 shows that:

CSG water production is forecast to continue to peak up to approx. June 2021;

The peaks are a result of contributions from the NW/NE development area;

From mid 2021 onwards the rate of CSG water production steadily declines then is anticipated to plateau between 2-3 ML/d from circa 2040.

A site water balance model has been undertaken to inform the re-evaluation of the CSG water management strategy based on this development profile (refer to Section 3.2 of this CWMP).

2.2.2 CSG water quality

The quality of CSG water is primarily dependent on the geology from which the CSG water is abstracted. Although CSG water quality from a given CSG well is expected to remain relatively consistent throughout its lifetime, the quality of CSG water from wells in different parts of a development area will vary.

Once produced to the surface, CSG water will be gathered to a CSG water management pond for temporary storage. During storage, the following natural processes will act to alter CSG water quality:

Mixing and homogenisation of CSG water from different parts of the development area;

Precipitation of metals such as aluminium, iron and manganese caused by contact with atmospheric oxygen;

Settling of fine suspended sediment;

Dissolution of carbon dioxide changing the carbonate-bicarbonate balance and altering pH; and

Change in temperature to approach ambient values.

Table 2-1 summarises the quality of CSG water produced in the SGDA based on MF Feed sampling (i.e. pond water that has been pumped from the pond to the plant and undergone coarse filtration to remove particulates), excluding any changes to feed water quality from expansion activities

Table 2-1: CSG Water Quality

Param

eter

Un

it

Lo

R

No

. of

Sam

ples

No

. of

Detec

ts

20th

Percen

tile

Med

ian

80th

Percen

tile

Inorganics

Alkalinity (Bicarbonate) as CaCO3

mg/L 1 204 204 1700 1800 1914

Alkalinity (Carbonate) as CaCO3

mg/L 1 204 204 87.6 164 225.4

Alkalinity (Total) as CaCO3

mg/L 1 204 204 1810 1938.5 2200

Ammonia as N mg/L 0.004 114 85 0.236 0.61 1.4

Bicarbonate mg/L 1 200 200 2074 2196 2342.4

Bromide mg/L 0.01 113 113 6.78 7.8 8.4

Calcium mg/L 0.01 200 200 8.56 9.4 11

Carbonate mg/L 4 200 200 52.68 99 137.88

Chloride mg/L 0.03 199 199 2330 2500 2800

Electrical Conductivity (Lab)

µS/cm 2 204 204 9500 10000 11200

Fluoride mg/L 0.01 202 202 4.9 5.7 6.5

Iodide mg/L 0.01 143 143 1.44 2.1 2.5

Magnesium mg/L 0.01 204 204 2.5 2.9 3.5

Nitrate (as N) mg/L 0.01 202 87 0.026 0.05 0.0856

Nitrite (as N) mg/L 0.001 202 65 0.0228 0.04 0.0658

Nitrite + Nitrate (as N) mg/L 0.002 198 102 0.0322 0.0625 0.13

Nitrogen (Total) mg/L 0.01 204 204 1.76 3.6 5.34




Param

eter

Un

it

Lo

R

No

. of

Sam

ples

No

. of

Detec

ts

20th

Percen

tile

Med

ian

80th

Percen

tile

Inorganics

Ortho Phosphorus (as P) (Filtered)

mg/L 0.002 198 155 0.0668 0.16 0.33

pH (Lab) pH_Units 0.1 204 204 8.7 9 9.1

Phosphorus mg/L 0.01 200 200 0.56 0.81 1.2

Potassium mg/L 1 200 200 15 16 20

Saturation Index - -10 197 197 1.242 1.5 1.658

Silicon as SiO2 mg/L 0.1 200 200 21.8 26 31

Sodium mg/L 0.01 204 204 2206 2505 2800

Sulphur as SO4 mg/L 0.6 200 58 1.1 1.6 3.14

Suspended Solids mg/L 1 204 202 19.2 34 56

Total Dissolved Salts mg/L 1 130 130 6100 6500 7600

Total Dissolved Solids mg/L 1 61 61 5900 6470 7600

Total Dissolved Solids (Calc)

mg/L 1 87 87 5800 6020 6400

Total Hardness as CaCO3

mg/L 1 200 200 32 36 41

Turbidity NTU 0.1 204 204 14 22 37.4

Metals

Aluminium mg/L 0.001 204 202 0.0752 0.43 1.1

Arsenic mg/L 0.0005 204 56 0.0015 0.0018 0.002

Barium mg/L 0.001 204 204 2.7 3 4

Boron mg/L 0.001 204 204 2.7 2.9 3.24

Cadmium mg/L 0.0001 204 1 0.0001 0.0001 0.0001

Chromium (III+VI) mg/L 0.0005 204 64 0.001 0.001 0.002

Cobalt mg/L 0.0002 200 7 0.001 0.001 0.001

Copper mg/L 0.001 204 39 0.001 0.002 0.00212

Iron mg/L 0.001 204 204 0.24 0.565 1.1

Lead mg/L 0.0002 204 2 0.00112 0.0022 0.00328

Lithium mg/L 0.001 88 88 1.3 1.4 1.628

Manganese mg/L 0.0005 204 203 0.022 0.035 0.0516

Molybdenum mg/L 0.001 204 7 0.001 0.001 0.0116

Nickel mg/L 0.0005 204 14 0.001 0.001 0.002

Selenium mg/L 0.001 204 0 ND ND ND

Silver mg/L 0.001 204 2 0.0012 0.0015 0.0018

Strontium mg/L 0.001 204 204 3.6 4.1 4.5

Tin mg/L 0.001 204 1 0.001 0.001 0.001

Zinc mg/L 0.001 204 62 0.003 0.004 0.00732

Organic

Total Organic Carbon as C

mg/L 0.5 198 197 8.44 18 29

2.3 Treated CSG Water

2.3.1 Treated CSG water production profile

Figure 2-3 illustrates how the forecast rate of treated CSG water production in the SGDA is predicted to vary to circa 2065 from 2018. The treated water profile follows the produced water profile as described in Section 2.2, however is constrained during the peak water production period by the Spring Gully Water Treatment Facility (WTF) treatment capacity.




Figure 2-2: Predicted Rate of Treated CSG Water Production

2.3.2 Treated CSG water quality

The most significant changes to the quality of CSG water will occur as a result of RO treatment. A detailed description of the treatment processes and facilities is provided in Section 5.2. Table 2-2 presents a summary of the quality of treated CSG water produced in the SGDA based on sampling of the combined permeate stream at the RO plant.

Table 2-2: Treated CSG Water Quality

Param

eter

Un

it

Lim

it of

Reporting

No

. of

Sam

ples

No

. of

Detec

ts

20th %

ile D

etected

C

on

cen

trati

on

Med

ian

Detec

ted

Co

nce

ntra

tio

n

80th %

ile D

etected

C

on

cen

trati

on

Inorganics Alkalinity (Bicarbonate) as CaCO3

mg/L 1 204 204 17 28 40

Alkalinity (Carbonate) as CaCO3

mg/L 1 204 6 1 1 2

Alkalinity (Total) as CaCO3

mg/L 1 204 204 17.6 28 40

Ammonia as N mg/L 0.004 114 83 0.017 0.08 0.21

Bicarbonate mg/L 1 200 200 20.74 34.16 47.58

Bromide mg/L 0.01 114 114 0.136 0.17 0.21

Calcium mg/L 0.01 205 25 0.2 0.3 0.4

Carbonate mg/L 1 200 200 0.6 0.6 0.6

Chloride mg/L 0.03 202 202 29 46.5 57

Electrical Conductivity (Lab)

µS/cm 2 205 205 130 220 270

Fluoride mg/L 0.01 202 153 0.0574 0.084 0.106

Iodide mg/L 0.01 142 129 0.0306 0.046 0.0664

Magnesium mg/L 0.01 204 5 0.058 0.07 0.172




Param

eter

Un

it

Lim

it of

Reporting

No

. of

Sam

ples

No

. of

Detec

ts

20th %

ile D

etected

C

on

cen

trati

on

Med

ian

Detec

ted

Co

nce

ntra

tio

n

80th %

ile D

etected

C

on

cen

trati

on

Nitrate (as N) mg/L 0.01 202 6 0.033 0.0365 0.048

Nitrite (as N) mg/L 0.001 202 39 0.002 0.003 0.007

Nitrite + Nitrate (as N) mg/L 0.002 198 99 0.003 0.004 0.00994

Nitrogen (Total) mg/L 0.01 204 187 0.03 0.075 0.208

Ortho Phosphorus (as P) (Filtered)

mg/L 0.002 198 134 0.003 0.004 0.007

pH (Lab) pH_Units 0.1 205 205 7.2 7.5 7.7

Phosphorus mg/L 0.01 200 114 0.014 0.023 0.037

Potassium mg/L 0.1 200 38 0.6 0.7 1.06

Residual Alkali as Na2CO3

meq/L 0.01 203 203 0.3 0.6 0.8

Saturation Index - -10 195 195 -3.004 -2.66 -2.388

Silicon as SiO2 mg/L 0.05 200 188 0.1 0.3 0.5

Sodium mg/L 0.01 205 204 26 44 56

Sodium Absorption Ratio

- 0.1 203 202 4 7 9.8

Sulphur as SO4 mg/L 0.2 200 3 0 0 1.44

Suspended Solids mg/L 1 204 3 5.4 6 18

Total Dissolved Salts mg/L 1 128 128 71 110 180

Total Dissolved Solids mg/L 1 62 62 63.2 98 133.2

Total Dissolved Solids (Calc)

mg/L 1 85 85 105 125 152

Total Hardness as CaCO3

mg/L 1 204 5 1 2 4.6

Turbidity NTU 0.1 204 53 0.1 0.15 0.2

Metals Aluminium mg/L 0.001 205 5 0.002 0.013 0.0278

Arsenic mg/L 0.0005 205 0 ND ND ND

Barium mg/L 0.001 205 205 0.009 0.03 0.0566

Boron mg/L 0.001 205 205 0.36 0.51 0.642

Cadmium mg/L 0.0001 205 1 0.005 0.005 0.005

Chromium (III+VI) mg/L 0.0005 205 0 ND ND ND

Cobalt mg/L 0.0002 200 0 ND ND ND

Copper mg/L 0.001 205 6 0.003 0.0035 0.004

Iron mg/L 0.001 205 71 0.004 0.009 0.014

Lead mg/L 0.0002 205 1 0.002 0.002 0.002

Lithium mg/L 0.001 86 85 0.0278 0.032 0.04

Manganese mg/L 0.0005 205 12 0.0012 0.002 0.0028

Molybdenum mg/L 0.001 205 1 0.003 0.003 0.003

Nickel mg/L 0.0005 205 0 ND ND ND

Selenium mg/L 0.001 205 0 ND ND ND

Silver mg/L 0.001 205 0 ND ND ND

Strontium mg/L 0.001 205 204 0.0176 0.04 0.0702

Tin mg/L 0.001 205 1 0.001 0.001 0.001

Zinc mg/L 0.001 205 53 0.002 0.005 0.013

Organic




Param

eter

Un

it

Lim

it of

Reporting

No

. of

Sam

ples

No

. of

Detec

ts

20th %

ile D

etected

C

on

cen

trati

on

Med

ian

Detec

ted

Co

nce

ntra

tio

n

80th %

ile D

etected

C

on

cen

trati

on

Total Organic Carbon as C

mg/L 0.5 198 35 0.578 0.65 0.912

2.4 Brine and Salt

2.4.1 Brine production profile

Figure 2-4 presents the forecast rate of brine production (in relation to produced and treated CSG water production) and resultant salt mass in the SGDA to circa 2065. Approximately 400,000 tonnes of salt will be produced over the project life.

Figure 2-3: Predicted Rate of Brine Production and Accumulated Salt Mass

2.4.2 Brine quality

The quality of the brine produced in the SGDA will vary over time in terms of both constituent salts and the concentration of total dissolved solids (TDS). This variation reflects both the characteristics of the CSG water being treated, and the design and operational parameters of the respective treatment facilities. Prevailing weather conditions will also affect the quality and concentration of brine as it is subject to solar evaporation while it is stored in brine ponds, prior to the final end-of-life management solution. The ratio of ionic components in brine is expected to approximate those of the CSG water being treated. Table 2-3 summarises the quality of brine generated in the SGDA, as it exits the water treatment facilities, prior to storage and concentration in brine ponds (i.e. reject, which is the data from all four reject streams that has been combined for statistical analysis).

Table 2-3: Brine Quality

Param

eter

Un

its

LO

R

Min

imu

m

Detec

ted

Co

nce

ntra

ti

Maxim

um

D

etected

C

on

cen

trati

on

Averag

e D

etected

C

on

cen

trati

on

10%ile

Detec

ted

Co

nce

ntra

tio

n

90%ile

Detec

ted

Co

nce

ntra

tio

n

Physical-Chemical pH (Lab) pH_Units 0.1 8.2 9.1 8.70 8.4 8.9

Total Dissolved Salts mg/L 1 10300 35600 27346.84 22750 32600




Para

mete

r

Un

its

LO

R

Min

imu

m

Detec

ted

Co

nce

ntra

ti

Maxim

um

D

etected

C

on

cen

trati

on

Averag

e D

etected

C

on

cen

trati

on

10%ile

Detec

ted

Co

nce

ntra

tio

n

90%ile

Detec

ted

Co

nce

ntra

tio

n

Total Dissolved Solids (Calc) mg/L 1 4000 41500 31509.79 27030 35700

Electrical Conductivity (Lab) µS/cm 2 1900 55700 41720.65 34280 49120

Major Cations and Anions Alkalinity (Bicarbonate) as CaCO3 mg/L 1 3300 21400 9597.42 7800 11300

Alkalinity (Carbonate) as CaCO3 mg/L 1 110 1021 486.03 236.5 734.3

Alkalinity (Total) as CaCO3 mg/L 1 3500 22200 10074.64 8214 12000

Bicarbonate mg/L 1 1.22 26108 11687.71 9516 13786

Bromide mg/L 0.01 0.94 95 43.64 31.5 58.5

Calcium mg/L 0.01 8 130 46.58 35.7 59

Carbonate mg/L 1 0.6 612.6 290.95 141 439.56

Chloride mg/L 0.03 491 19900 13088.09 10900 16000

Fluoride mg/L 0.01 1 49 28.74 21 38

Iodide mg/L 0.01 1.5 48 12.01 7.54 17

Magnesium mg/L 0.01 2.9 22 13.61 9.5 18.7

Phosphorus mg/L 0.01 0.5 27 8.59 4.78 13

Potassium mg/L 1 36 250 84.05 63 107

Silicon as SiO2 mg/L 0.1 0.9 220 112.52 72.4 160

Sodium mg/L 0.01 440 18000 12496.48 10300 15000

Sulphur as SO4 mg/L 0.6 1.4 98 14.17 2.16 34.8

Total Hardness as CaCO3 mg/L 1 38 390 172.11 130 220

Total Organic Carbon as C mg/L 0.5 5.8 520 38.51 17 71

3. CSG Water Management Strategy

This section of the CWMP describes and justifies the strategy for managing CSG water produced in the SGDA.

3.1 Strategy Drivers

3.1.1 Australia Pacific LNG’s CSG water management philosophy

Australia Pacific LNG is committed to managing CSG water in order to maximise its beneficial use whilst minimising the associated development footprint and protecting EVs. To account for the inherent uncertainties associated with predicting the quantity and quality of future CSG water production, as well as those associated with unpredictable events such as extreme wet weather, Australia Pacific LNG’s future CSG water management strategy seeks to ensure that sufficient capacity is available for 100% beneficial use.

3.1.2 History and Current Operations of the SGDA

The full-scale production of CSG and associated CSG water in the SGDA commenced in 2005. CSG water management infrastructure was designed and constructed in accordance with the regulation of the time and initially comprised a series of CSG water management ponds used to store the produced CSG water.

In order to reduce the reliance on ponds for storage, and to establish the capability to support future beneficial uses of CSG water as they became feasible, in 2007, Australia Pacific LNG constructed the Spring Gully WTF. Treated CSG water from the WTF was initially released to Eurombah Creek in accordance with the Spring Gully EA. Brine generated at the WTF was stored in ponds.

The Spring Gully WTF represented Australia Pacific LNG’s first significant WTF and provided the opportunity to confirm the viability of management options that could then be applied to the broader Australia Pacific LNG Project as it was developed. These option assessments included the following.




Irrigation – In 2008, a trial plantation irrigating Pongamia Pinnata with treated CSG water was established in the vicinity of the WTF to test the growth and frost tolerance of the species in the regional climate and environment. Pongamia Pinnata is a rapid growing Australian native legume tree that produces a high yield of seeds that have a range of beneficial uses (Scott et al. 2009). On the basis of the outcomes of the trial, in 2010, a 300 ha plantation of Pongamia Pinnata was proposed (with 285ha actually established) on the Australia Pacific LNG property of Spring Gully utilising treated CSG water for irrigation.

Aquifer Injection – In 2010, a series of phased investigations with the aim of determining the feasibility of injecting treated CSG water into underground formations were commenced. Initial data acquisition indicated the presence of appropriate receiving formations and in April 2012, a 12-month aquifer injection trial was undertaken in accordance with the Spring Gully EA. The trial was able to confirm the technical feasibility of injecting treated CSG water into the Precipice Sandstone. As a result, a full-scale Spring Gully aquifer injection scheme has been constructed and is operational.

Brine Management – Australia Pacific LNG has completed a Brine Investigation Report (BIR) (Q-LNG01-95-RP-1763) which details the studies undertaken to investigate options for the management of salt and detail the Project’s preferred salt management option. The SGDA was included in brine investigations for an Australia Pacific LNG Project preferred solution.

Australia Pacific LNG’s investment in the development of the above option assessments has enabled the original CSG water management strategy of the SGDA to be progressively enhanced so that it currently comprises the following beneficial uses of CSG water.

Project Activities – In order to reduce demand on other regional water sources, Australia Pacific LNG uses CSG water, treated CSG water or a blend of untreated and treated CSG water, to suppress dust, as well as to support construction activities (such as drilling, well completions and work-overs, hydraulic fracture stimulation, facilities construction, hydro-testing of gathering networks), landscaping and rehabilitation.

Irrigation (and Livestock Watering) – The current operation of the Pongamia Plantation consists of the irrigation of 285 ha of Pongamia pinnata using treated CSG water from the WTF. Treated CSG water may also be used to water stock on Australia Pacific LNG properties in the development area if required.

Aquifer Injection – The full-scale Spring Gully aquifer injection scheme commenced operation in Q3 2015 and can inject a maximum of 8.1 ML/d of treated CSG water into the Precipice Sandstone aquifer.

Through the progressive implementation of these beneficial uses, Australia Pacific LNG has gradually and consistently reduced the proportion of treated CSG water that it releases to Eurombah Creek (excluding 2017 calendar year). Release of treated CSG water is currently used intermittently, when the demand for beneficial uses (project activities, aquifer injection and irrigation) is insufficient to manage the quantity of treated water.

The brine generated at the WTF is transferred to a series of brine ponds for storage, and evaporation, prior to implementation of the final salt management solution.

The above portfolio represents the existing CSG water and brine management strategy of the SGDA. This CWMP evaluates whether or not this strategy continues to reflect the most appropriate solution for managing the volume and quality of future CSG water expected to be produced. In turn, and where required and where proven feasible, enhancements to the current strategy are proposed.

Where the annual review of the site water balance model (as required by the EA) identifies constraints in the CSG water management scheme, further evaluation of the currently approved CSG water management strategy will be undertaken to identify if any augmentation of the current beneficial use scheme is required.

3.1.3 Australia Pacific LNG Project EIS Local Needs Analysis

To support the development of the Australia Pacific LNG Project Environmental Impact Statement (Australia Pacific LNG, 2010) (the Australia Pacific LNG Project EIS), Australia Pacific LNG evaluated the potential performance of more than 70 CSG water management options (grouped into the six (6) categories presented in Error! Reference source not found.) for its development areas across south central Queensland in line with the priorities of the CSG Water Management Policy (DEHP 2012).

Note: Whilst the SGDA was not included in the EIS study area, the Australia Pacific LNG EIS Project informed the SGDA re-evaluation with SGDA operated as part of the Australia Pacific LNG Pty Limited.




Table 3-1: Categories of CSG Water Management Option

Category Description Position on DEHP Hierarchy

Municipal use Supply of treated CSG water to townships for municipal use. Priority 1

Agriculture Supply of treated CSG water for agricultural uses including:

1. Existing irrigated cropping or livestock watering operations.

2. To support new irrigation or livestock watering schemes.

3. Agricultural ventures operated by Australia Pacific LNG or third party(ies)/landholders.

Priority 1

Industrial use Supply of untreated or treated CSG water to industrial users Priority 1

Project activities

Use of untreated, treated (or blended) CSG water to support Australia Pacific LNG Project activities such as dust suppression and construction. Construction activities include drilling, well completions and workovers, hydraulic fracturing, facilities construction, hydro-testing of gathering networks and landscaping and rehabilitation.

Priority 1

Injection Injection of treated CSG water to a depleted aquifer. Priority 1

Injection Injection of untreated or treated CSG water to a basement formation.

Priority 2

Release to surface water

Release of treated CSG water to surface watercourses in a manner that ensures the protection of EVs.

Priority 2

CSG water management options implemented for Australia Pacific LNG (EIS bound) gas fields, based on local needs analysis and defined option selection criteria, is listed below.

Table 3-2: CSG Water Management Strategies for Australia Pacific LNG EIS gas fields

Gas Field Water Management Strategy Description Position on DEHP Hierarchy

Approval Governing Activity(ies)

Condabri and Talinga/Orana

100% beneficial use via:

Agriculture - Irrigation (treated water to landholder scheme known as Fairy Meadow Road Irrigation Pipeline)

Project Activities

Priority 1

General Irrigation BUA

General BUA

EPPG00853013

EPBC 2009/4974

Contingent treated water release to surface waters - Condamine River

Priority 2

Combabula 100% beneficial use via:

Aquifer Injection (treated water to Precipice and Hutton Sandstone)

Project Activities

Priority 1

EPPG008532132

EPBC 2009/4974

General BUA

Contingent treated water release to surface waters - Yuleba Creek

Priority 2

3.2 Re-evaluation of the SGDA CSG Water Management Strategy

The capacity of the current CSG water management strategy and existing infrastructure to manage the forecast water production profile including the contribution of the NW/NE area of the SGDA without an ongoing reliance on creek discharge was evaluated. The evaluation found that additional capacity was required to achieve beneficial use of the treated water, and manage brine, and that a transition stage would be required to enable continued operation of the WTF until additional capacity is constructed.

2 The discharge approval to release treated CSG water to Yuleba Creek under EA EPPG00853213 has expired.




During this transition stage there would be continued reliance on river discharge within the existing EA limits.

In order to transition, the following option categories have been re-evaluated:

Agriculture;

Injection (treated water); and

Release to surface waters.

This re-evaluation assumes municipal use, industrial use and injection of untreated CSG water remain infeasible as per evidence provided in previous versions of this CWMP.

As there is no change to the proposed use of CSG water (untreated/produced and treated/permeate for project activities in accordance with the General Beneficial Use Approval Associated Water (including coal seam gas water) (DEHP 2014) (the General BUA), this has not been included in this re-evaluation.

3.2.1 Irrigation Scheme (Agricultural Use)

The current agricultural use within the SGDA is the 285 ha Pongamia Pinnata plantation which has been operational since 2010, irrigated by treated CSG water. The supply of treated CSG water to this scheme is currently authorised under the General Beneficial Use Approval Irrigation of Associated Water (including coal seam gas water) (The Irrigation General BUA) (DEHP 2014).

Daily irrigation rates have varied between zero and 6.8 ML/d dependent on seasonal climate and day-to-day weather with a sustainable annual average of 3.1 ML/d recommended.

Analysis into the potential to expand the irrigation demand at Spring Gully has been undertaken to increase the beneficial use capacity. This analysis identified the potential to increase the irrigation demand by constructing a 137ha centre-pivot irrigation scheme in addition to operating the existing 285ha Pongamia scheme.

The entire irrigation scheme would be operated to include:

Operation and maintenance of the existing Pongamia plantation (drip irrigation system);

Four (4) x 34 ha centre pivots of perennial Rhodes grass and annual cropping (corn/oats), which ties into the Pongamia distribution line between Pongamia and the dam; and

350 ML dam for permeate buffer storage.

The Expansion Irrigation Scheme has been designed to ensure an average annual irrigation rate of approx. 5.6 ML/d with seasonal usage buffered by 350 ML dam, dependent on water availability.

The modelling for the proposed expansion of the irrigation scheme has been undertaken using SOURCE 4.1.1 developed by eWater CRC (www.ewater.com.au), chosen due to industry acceptance and modelling capabilities. SOURCE models the crop usage for irrigation on a soil moisture deficit basis, to reflect the processes that will be used during the operation of the irrigation facility.

Specific data used for the irrigation modelling is provided below.

Meteorological data including rainfall, evaporation and evapotranspiration is sourced from the SILO database. The model used 100 years of SILO data from 1917 to 2017.

Evaporation data applied to the storage dam was multiplied by a pan coefficient of 0.8.

Arable soil depth of 0.9m and Plant Available Water Capacity of approximately 125mm, based on sampling of soils in the proposed irrigation expansion areas. Target soil water depletion varies from 30 to 60mm in summer, and 20 to 50mm in winter over the life of the project, to avoid crop stress events.

Crop types are a combination of silage and grazing crops to support and optimise the agricultural activities undertaken in the region. Crop usage varies over the life of the project to suit available water supply. Example of crops that may be grown are corn, barley, oats, Rhodes grass, sorghum and millet.

The Expansion Irrigation Scheme aims to:

Subject to CSG water availability, apply irrigation water in balance with crop evapotranspiration demand and soil water holding capacity;

Prevent overland flow and runoff of applied irrigation water; and




Induce controlled leaching as required to manage the distribution of native and applied salt in the crop root zone.

During the Transition Stage, existing irrigation of the Pongamia plantation will occur and be supplemented by filling of the dam once constructed.

Note: This scheme provides a future option to increase capacity of the Spring Gully WTF by providing blended water (produced water plus permeate) for irrigation, subject to beneficial use approval.

3.2.2 Aquifer injection

The Spring Gully aquifer injection scheme was modelled with an injection capacity of up to 8.1 ML/d of treated CSG water into the Precipice Sandstone. The Spring Gully Aquifer Injection – Technical Feasibility Assessment (Q-8200-95-TR-0015) identified the Precipice Sandstone as the most suitable target for aquifer injection and the subsequent trial concluded that a full-scale injection scheme would be technically feasible.

However, since the full aquifer injection scheme became operational, its performance has not met design specifications due to operational issues with the Permeate Injection Plant (PIP) (i.e. no reservoir constraint). Current performance has been limited to an annual average of approx. 1.5 ML/d.

A project to currently underway to improve the capacity and reliability of the PIP to achieve an instantaneous capacity of 5ML/d and an annual average capacity of 3.5ML/d (based on site water balance modelling requirements).

3.2.3 Release to Surface Waters

The current EA EPPG00885313 authorises release of treated CSG water to a tributary of Eurombah Creek up to 700 ML/yr, with a cessation date of 31 March 2020. Internal decisions have resulted in Origin Energy choosing to cease river discharge once the Transition Stage has been completed.

During the Transition Stage, contingent discharge to Eurombah Creek is required for ongoing operations whilst the water management capacity is constructed to support the NW/NE expansion (including exploration and appraisal activities connected to existing gathering infrastructure).

3.2.3.1 Protection of Environmental Values during the Transition Stage

To monitor the environmental performance of the contingency release scheme, Australia Pacific LNG will continue the current receiving environment monitoring program (REMP) in accordance with the Spring Gully EA. The Spring Gully Receiving Environment Monitoring Program: Eurombah Creek (8600568) (the Eurombah Creek REMP) has been implemented since August 2011 and its regular monitoring of flow, aquatic habitat, bank stability, water quality, sediment quality, phytoplankton, zooplankton and aquatic macrophytes has found no evidence of environmental harm or detrimental impact to EVs from to the release of treated CSG water from the WTF. This demonstrates that Australia Pacific LNG’s management practices are effective in ensuring that the release scheme can be implemented in an environmentally compliant manner.

As such, and considering the ability of release acts as a reliable contingency to the beneficial use portfolio of the SGDA during the Transition Stage, the option is considered to be fully aligned to the CSG Water Management Policy (DEHP, 2012) at this time.

3.3 Transition Stage and Future SGDA CSG Water Management Strategy

The SGDA CSG permeate water management strategy is presented in Table 3-3, based on a predicted peak constrained treated water profile of 10.2 ML/d over the next 2 years.

The SGDA brine management strategy is addressed in Section 4 of this CWMP.

Table 3-3: SGDA Transition Stage and Future CSG Water Management Strategy (Excluding Brine)

Strategy Water Management Strategy Description Position on DEHP Hierarchy


Transition Stage

Beneficial Use of CSG water for:

Project Activities

Agriculture - Irrigation (treated water to the landholder scheme - Pongamia plantation/dam filling)

Aquifer Injection (treated water to Precipice sandstone)

1

General BUA


EPPG00885313




Strategy Water Management Strategy Description Position on DEHP Hierarchy


Contingent treated water release to surface waters – Eurombah Creek

2

Future Beneficial Use of CSG water for:

Project Activities

Agriculture - Irrigation up to 7.5 ML/d

Aquifer Injection (treated water to Precipice sandstone) up to ~5 ML/d

1

General BUA


EPPG00885313

EPBC2017/78813

3.4 SGDA (Site) Water Balance Model To support the development and implementation of the future Spring Gully CSG water management strategy outlined in this CWMP (i.e. re-evaluation of the current strategy), Australia Pacific LNG has developed a site water balance model using GoldSim Pro (GoldSim) modelling software. GoldSim is a general purpose probabilistic simulation tool used to undertake reliability and risk assessments by quantitatively addressing uncertainty inherent in complex systems, and used extensively by the CSG industry.

The model simulates the performance of CSG water and brine management infrastructure and is used to optimise this infrastructure based on the predicted rates of CSG water production, WTF performance, and the effects of rainfall and evaporation. A salt mass balance is also included within the model to account for salinity effects and to permit evaluation of brine management options.

The specific objectives of the site water balance model are as follows:

To optimise the size, configuration and timing of implementation of CSG water and brine management infrastructure;

To evaluate the risks associated with the CSG water and brine management scheme containing forecast CSG water volumes in response to extreme weather; and

To allow for continued monitoring of the performance of CSG water and brine management infrastructure and to test performance against future predictions of CSG water production.

To ensure that the methodology and assumptions of the Spring Gully site water balance model remain appropriate to any changes in the CSG water management strategy, the model undergoes quarterly recalibration and validation with a detailed forecast for 2+ years and annually for life of project.

The model has been configured to ensure all treated CSG water can be injected when not used for the Expanded Irrigation Scheme. Key inputs in the GoldSim model to achieve this outcome included:

Median (P50) water profile generated by Enersight modelling software including the Eurombah to Reedy Creek Interconnect in operation based on reservoir assessment;

1:100 year rainfall event occurring in 1956, based on SILO database (http://www.longpaddock.qld.gov.au/silo) ranging from 1/1/1889 to 2/3/2016;

1.26 – 1.65 ML/d produced from the Reids Dome pilot commencing February 2018 to June 2021;

Spring Gully WTF treatment capacity of 12 ML/d, recovery rate of 80%, availability of 85%, and treatment capacity after availability of 10.2 ML/d (therefore assuming 8.16 ML/d treated water volume and 2.04 ML/d brine volume);

Proposed irrigation rates for the proposed Expansion Irrigation Area, growing a mixture of forage and silage crops, and 285 ha Pongamia plantation (refer to Section 3.2.1.1);

350 ML treated water storage dam as a storage buffer based on design dimensions of 10 ha water surface area and 3.5m depth profile;

3.5 ML/d continuous annual average aquifer injection capacity;

0 ML/d discharge to Eurombah Creek; and

3 Subject to Approval Decision by the Australian Government Department of the Environment and Energy




0 ML/d project activities (as the demand profile is not continuous or long term).

A detailed analysis of the peak production period at Spring Gully has been presented in Figure 3-1.

The site water balance model, based on these assumptions verifies that there is no permeate excess (modelled as no dam overflow) for a 1 in 100 wet rainfall year (with the exception of unforeseen events which would be controlled by field turn when the pond ullage is not available) during peak water production period of 2017 to 2021.

The site water balance model, based on current brine storage volumes, also identifies the requirement for an additional brine dam with a capacity of up to 400 ML to be operational by 2020.

Refer to the following graphical evidence of model outputs:

Figure 3-2: Spring Gully Additional Irrigation Demand during Peak Production

Figure 3-3: Spring Gully Existing Irrigation Demand during Peak Production

Figure 3-4: 350 ML Storage Dam Volumes and Evaporation Rates

Figure 3-5: Spring Gully Aquifer Injection Rates

Figures 3-2 and 3-3 identifies the irrigation demand varies over seasons with peaks during Summer periods when there is high evaporation rates. Figure 3-2 also confirms that a maximum instantaneous aquifer injection rate of up to 5 ML/d would offset any irrigation peaks considering the corresponding storage dam volume peaks (Figure 3-4) do not exceed the design capacity of the dam. Figure 3-4 identifies sufficient capacity in the 350 ML storage dam to prevent an excess water/overflow. From an operations perspective, the site will be managed to prioritise water supply to irrigation whilst ensuring aquifer injection is utilised primarily during low demand periods (nominally during Winter). Figure 3-5 identifies a continuous injection rate of 3.5 ML/d will be required for up to 40 years.

Figure 3-1: Detailed Analysis – Spring Gully Peak Production CSG Water Profile (2017-2020)




Figure 3-2: Spring Gully Additional Irrigation Demand During Peak Production

Figure 3-3: Spring Gully Existing Irrigation Demand During Peak Production




Figure 3-4: 350 ML Storage Dam Volumes and Evaporation Rates During Peak Production

Figure 3-5: Spring Gully Aquifer Injection Rates

Note: Work in currently underway to provide the required beneficial use capacity which has been modelled. Specifically:




Expansion of the existing irrigation scheme (refer to Section 3.2.1); and

Upgrade the capacity and reliability of the aquifer injection scheme to achieve instantaneous capacity of 5 ML/d with 70% availability (refer to Section 3.2.2).

Quarterly integrated water balance modelling is undertaken by Operations for detailed two (2) year forecasting review underpinned by actual data as part of portfolio optimisation, including dam (feed and brine) capacity and storage, and permeate capacity (i.e. sensitivity analysis as per Section 2).

3.5 CSG water management for E&A programs

CSG water produced during the operation of pilot CSG wells is typically stored in pilot ponds or tanks as these activities occur in remote locations from the CSG water gathering and treatment infrastructure.

Table 3-4 evaluates alternative options for the management of this CSG water. For E&A programs, the typically low volumes of CSG water production and the limited time period over which CSG water is produced act to prevent the establishment of long-term sustainable, independent schemes for the use of CSG water. Unless supplementary water supplies are also secured, any beneficial use scheme could only operate for a short period of time. Furthermore, the majority of potential uses of CSG water would require that CSG water undergoes prior treatment, necessitating infrastructure that would (eg. Reids Dome) have a large development footprint in comparison to the volume of treated CSG water that could be generated for beneficial use.

Table 3-4: Option Evaluation for SGDA E&A CSG Water Management

Option Assessment of Feasibility

Use of untreated CSG water for project activities

Where practicable, and where this can be conducted in accordance with the conditions of the General BUA, CSG water will be used for project activities.

Use of treated CSG water for agricultural, industrial or municipal supply, or for aquifer injection

The small volumes of expected CSG water production, and the limited time period over which this resource would be available, prevent the establishment of long-term sustainable beneficial uses of CSG water.

Reflecting the required development footprint, it is not considered environmentally or economically appropriate to treat the produced CSG water to an acceptable standard for agricultural, industrial or municipal use, or for aquifer injection.

Storage of CSG water in pilot ponds or tanks

This is considered to be the most appropriate initial CSG water management option where CSG water cannot be used for project activities.

Pilot ponds or tanks will be constructed in accordance with prevailing regulation and /or relevant Australian Standards. Dependent on the outcomes of the E&A program, any remaining stored CSG water will be managed via one of the following options:

Transfer via tanker or pipeline for treatment at the Spring Gully WTF and subsequent beneficial use; or

Transport off site using a regulated waste transporter to existing facilities for disposal.

Release of CSG water to surface waters

Release of CSG water to surface watercourses is not considered an appropriate option due to water quality constraints.

4. Brine and Salt Management Strategy

Produced CSG water is treated by the WTFs using reverse osmosis (RO) technology to produce high quality treated water that is suitable for numerous beneficial uses. A by-product of the RO treatment is a saline water stream which is also referred to as brine.

The BIR (Q-LNG01-95-RP-1763) has been prepared in consideration of four (4) identified options for brine management: selective salt recovery (SSR), brine injection, encapsulation and ocean outfall. The objective of the BIR is to present:

The results of brine management option investigations required by the relevant development area’s EA and Coordinator-General Approval

A summary and ranking from most to least preferred of all brine management options investigated; and




The preferred brine management option.

The brine and salt strategy is consistent across the individual development areas (Walloons, Condabri, Combabula and Spring Gully) of the Australia Pacific LNG Project.

This CWMP has been updated to present the updated brine and salt management plan in alignment with the results of the BIR.

4.1 Option evaluation and assessment criteria

Option evaluation and assessment criteria are shown in Figure 4-1 and follow a two (2) gate process.

The first gate for assessment was a fatal flaw analysis for the option requiring it be compatible with the following requirements of the Australia Pacific LNG project:

The option must be technically feasible over the lifetime of the project;

The option must not pose an unacceptable risk to the production of CSG considering time, reliability and flexibility; and

The option must be compliant with prevailing regulations and/or be approved by the administering authority within the timeframes required by the Australia Pacific LNG project.

The second gate evaluated the option against performance assessment criteria from a range of categories including environmental impact, health and safety, alignment with regulation and social impact, and designed to ensure the option was consistent with Australia Pacific LNG’s philosophy, regulations and commitments made in the Australia Pacific LNG EIS. The ongoing review of the options by Australia Pacific LNG identified a range of sub options (n = 76). Over a staged process, 15 sub options were identified for detailed analysis across the Triple Bottom Line.

Figure 4-1: Option Identification and Evaluation Process

4.1.1 Selective Salt Recovery (SSR)

Selective Salt Recovery (SSR) is a unique combination of existing technologies to produce salt products from CSG brine for potential beneficial reuse. Concentrated brine would be transported to the SSR facility through a purpose built brine pipeline and stored in a holding pond at the SSR facility. Salt crystallisers would then be used to fractionally crystallise brine into sodium chloride (table salt) and sodium carbonate (soda ash). The resulting salt products would then be available for transportation by rail prior to shipping to the international market.




SSR is a Priority 1 option however SSR has been considered infeasible for reasons including:

Insufficient market demand to be assured of sale of the salt products;

Prohibitive cost, where the cost to transport the salt products to market typically exceeds the market value of the product;

Large capital cost for the infrastructure required, being the brine aggregation pipelines and SSR facility; and

Significant energy consumption and land disturbance impacts are required to undertake SSR.

4.1.1.1 Brine Injection

The feasibility of a brine solution based on injection is dependent on finding a geologically isolated formation which contains sufficient capacity for the forecast brine volume produced by the industry which either:

Does not contain groundwater; or

Where groundwater is present that the brine is of a similar or better quality than in-situ groundwater so as to minimise the potential for environmental harm to occur.

Australia Pacific LNG investigations found that reservoir permeability is either too low to support brine injection and/or there was uncertainty regarding the containment of injected brine/isolation from overlying aquifers.

Consideration was also given to dilution of brine but under the current policy framework this would negate the beneficial use of treated water and also increases the volume for injection. Further, injection of a diluted brine solution would need to occur at a significant depth below the Great Artesian Basin which, along with the uncertainties in the occurrence of appropriate structures, introduces significant technical risks of accessing a highly pressurised system at depth.

As no suitable injection target could be identified, brine injection was assessed as being infeasible.

4.1.1.2 Ocean Outfall

The Ocean Outfall option requires the construction of a ~250km infield brine pipeline network connecting brine ponds across Australia Pacific LNG gas fields and a 370km pipeline to a coastal ocean outfall (Tugun desalination plant) for discharge. Concept design and route selection were completed in collaboration with another proponent. Upon detailed analysis, this option was considered infeasible on grounds of cost and social acceptance due to the significant construction effort required for implementation and associated land disturbance.

It is noted that Ocean Outfall is the only option which avoids residual liability, that is, once discharge ceases there will be limited or no ongoing monitoring and management and the pipeline can potentially be used for other purposes, as can the outfall. All other options require extended ongoing monitoring and management and / or extensive decommissioning processes.

4.1.1.3 Encapsulation

Salt encapsulation involves the conversion of stored brine to a mixed salt using a mixed salt crystalliser for long-term storage and containment in salt encapsulation cells (see Figure 4-2), otherwise known as Regulated Waste Facilities (RWFs). A range of studies have been undertaken on all of the elements of the salt encapsulation option since 2010. These have included studies on both the infield brine pipelines, the technologies required to crystallise the brine as well as the RWF, in particular various technologies and techniques were considered during the study for the RWF approach and RWF method to assess their suitability. The methods considered involved proven technologies that are commercially available on the market and represent industry practice. From the assessments indicated above the following was recommended:

The landfill approach should be Archival (i.e. Engineered to contain wastes indefinitely, but also to permit later identification and retrieval).

The landfill method should be Mono Disposal (i.e. Disposal of waste with the same general physical and chemical form. Once deposited, the wastes may not necessarily remain in the same physical form).

Given the large geographic spread of Australia Pacific LNG’s WTFs, it is recognised that the salt encapsulation option could be undertaken using either a centralised or decentralised infrastructure arrangement, therefore a number of scenarios were considered.

The preferred concept involves a decentralised option underpinned by best practice environmental design principles with the resultant scheme described in Section 5.3 of this CWMP.




Figure 4-2: Salt Encapsulation SchematicRanking of assessed brine and salt management options

The ranking of the brine and salt management options, as described above, is as follows.

1st –Encapsulation - the lowest environmental impacts and cost of the options considered.

2nd - Ocean outfall - the environmental impacts, associated disturbance and overall cost and complexity of implementation exceed that for encapsulation.

3rd – SSR - considered infeasible due to environmental, market and cost impacts.

4th - Brine injection - infeasible due to technical reasons which prohibit its adoption.

4.2 Long Term Management Strategy

The long term management strategy of brine/CSG salt has been a result of collaboration within the CSG industry since 2010. At that time the long-term brine management strategy developed by each Proponent involved the temporary storage of brine in dedicated brine ponds and final encapsulation of the CSG salt.

In recognition that brine storage (and concentration via solar evaporation) is the first management action and subsequent collaboration within the CSG industry, Australia Pacific LNG’s long term brine/CSG salt management strategy is Encapsulation based on the above ranking of options. A representation of the combined brine management strategy is presented in Figure 4-3. Specific to Spring Gully, brine will be stored in dedicated ponds until transferred by an infield brine pipeline to Reedy Creek WTF for crystallisation and containment at the RWF (subject to approvals).

Figure 4-3: Brine Management Strategy

5. CSG Water, Brine and Salt Management Scheme




This section of the CWMP explains how the CSG water and brine management strategies outlined in Section 3 and 4 will be implemented. It includes a description of the infrastructure required to gather, store, treat and use CSG water and brine in the SGDA.

5.1 Untreated CSG water management scheme

5.1.1 CSG water gathering network

To release CSG from a coal seam, the water pressure that holds it in place must be reduced, a process that is achieved by drilling a well into the coal seam and abstracting water, often using a lift pump. As a result, CSG and CSG water flow up the CSG well to the ground surface where they are separated by a wellhead separator. The CSG water is then conveyed in a low-pressure, buried, high density polyethylene (HDPE) pipeline network to the feed pond of the WTF (see Section 5.1.2).

The design and construction of the CSG water gathering network uses the existing topography of the landscape to optimise pressure and thereby reduce operational energy requirements. However, to maintain delivery of water to the WTF, at intermediate points along the network, Water Gathering Stations (WGS) and Water Transfer Stations (WTS) may be installed. WGS and WTS consist of a pumping station and an associated above ground tank or storage pond.

WGSs and WTSs ensure continuity of flow and also provide redundancy in the event of downstream pipeline issues. Any CSG water stored in the tank or pond of a WGS or WTS as a result of such an issue will be pumped to the WTF immediately on resumption of the operation of the downstream gathering network.

Existing WGS and WTS ponds in the SGDA are located at Strathblane dam, Taloona tank (replaced decommissioned dam), Lighthouse tank, Waikola tank, Nuggett Hills tank and Echo Hills tank. In addition, tanks are installed at four (4) locations (Lighthouse, Waikola, Nuggett Hills and Echo Hills).

5.1.2 CSG water storage

5.1.2.1 Exploration and Appraisal phase

Exploration and Appraisal (E&A) CSG activities applicable for this Spring Gully CWMP will be undertaken in the ATP administered by the Injune EA or in locations administered by the Spring Gully EA. CSG water produced during the drilling and operation of pilot CSG wells is typically initially stored in pilot ponds or tanks (except where predicted volumes make this on site option infeasible).

CSG water produced at single-well pilots will initially be stored in tanks sized to account for both the total volume of CSG water predicted to be produced, and an allowance for wet weather. On average, evaporation in the SGDA exceeds rainfall in every month of the year (see Section 6.1). However, in order to account for the rare periods during which rainfall may exceed evaporation, a freeboard allowance is incorporated into the capacity of each tank.

CSG water stored in pilot tanks will be managed in accordance with the strategy presented in Section 3.5. Once the operation of the pilot well ceases, the associated tank or dam is taken offline. The tank or dam will then remain in place to be monitored and maintained whilst the broader E&A program continues. Following completion of the E&A program, any CSG water remaining in dams or tanks will be transferred by tanker (or via the production scale gathering network if production-scale CSG activities are progressed) to an appropriate WTF, preferentially for beneficial use, or if approved under the EA, left in situ to evaporate.

Once dewatered, tanks will be dismantled and removed from the site. Ponds will be decommissioned and remediated if not required for beneficial use by the Landholder or Third Party. The sites of ponds and tanks will then be rehabilitated in accordance with the Spring Gully Development Area Rehabilitation Plan (CDN 12883952).

Where E&A activities will rely on the existing CSG water management scheme, verification that the strategy remains valid will be required using site water balance modelling.

5.1.2.2 Full-scale CSG production phase

CSG water produced at production CSG wells is currently gathered to the WTF Feed Pond (which has been constructed in the footprint of Cell 1 of the existing Spring Gully Pond A), an integrated system designed with two (2) cells. The WTF Feed Pond provides a preliminary treatment function through oxidation and settlement processes along with buffer storage capacity between field production and WTF inflows.

The characteristics of the CSG water storage ponds are described in Table 5-1.




Table 5-1: CSG Water Storage Feed Ponds in Operation

Name Capacity at Top Operating Water Level (ML)

Depth of Stored Water at Top Operating Water Level (TOWL) (m)

SGWTF Feed Pond – West 60.1 3.04

SGWTF Feed Pond – East 60.5 3.04

5.1.3 Untreated CSG water use

Wherever practical, Australia Pacific LNG will use CSG water to support project activities. The use of untreated CSG water for these purposes will be conducted on a case-by-case basis dependent on the volume and quality of the CSG water stored and the volume and quality of the water required, as well as the location of the demand in relation to CSG water storages. Use of untreated CSG water for project activities will be based on technical recommendations from dedicated studies (eg. Aecom 2016 ‘CSG Water Dust Suppression Calculator’, Q-1000-15-RP-077).

Any use of untreated CSG water to support project activities will be conducted in accordance with the General BUA and internal procedures.

Additionally, the Spring Gully EA authorises the release of untreated CSG water to land from LPD management and for hydrostatic pressure testing. A procedure for LPD water quality sampling has been prepared (CDN 3675692). Release limits are specified in the Spring Gully EA. For hydrostatic test water, releases to land must meet EA water quality limits which are consistent the LPD release limits. Further requirements for LPD and hydrotest water releases are described in the Land Release Management Plan (CDN 11970260).

5.2 Treated CSG water management scheme

5.2.1 CSG Water Treatment

The WTF was constructed in 2007 and has a maximum treatment capacity of 12 ML/d. Recent re-evaluation of the numerical model used to predict rates of CSG water production has shown that CSG water production rates will require management within the capacity constraints of the existing CSG water infrastructure during the peak water production period.

Figure 5-1 presents a simplified process flow diagram of the treatment processes at the WTF. They can be summarised into the following four (4) process steps:

1. Temporary storage in the WTF Feed Pond to provide buffer storage, aeration, and removal of coarse sediment and to allow for stabilisation in the temperature of CSG water prior to entering the facility;

2. Pre-treatment technologies to remove larger particles and adjust pH to improve the desalination process;

3. Desalination using RO; and

4. Conditioning of treated CSG water to ensure suitability for end use.

5.2.1.1 Feed Pond

CSG water is gathered to the Feed Pond at the WTF for aggregation and temporary storage. Whilst in storage the Feed Pond allows for the settlement of coarse suspended sediments and for oxygenation of CSG water.

The feed pond storage capacity at its TOWL is 121 ML (refer Table 5-1). It has an internal division into two (2) compartments: a buffer compartment and a feed compartment, of approximately equal capacity.

The Feed Pond’s typical operation is for the field inflows to be directed to the feed compartment, and for recycled water from the WTF and other water sources to enter the buffer compartment which then flows into the feed compartment. The process flow for the WTF is drawn from the feed compartment. However the pond design provides operational flexibility and also permits the inflows to be directed to either compartment, or for a compartment to be isolated. The buffer compartment typically sits at a consistent level near TOWL to allow for management of the volume re-processed in the feed water to the WTF.

5.2.1.2 Filtration

CSG water drawn from the WTF feed pond is screened to remove any particles, suspended sediments or biological organisms. CSG water first passes through a disc filtration (DF) unit (400 m) followed by a finer membrane filtration (MF) unit to produce a very low turbidity feed water suitable for the




downstream RO process. The turbidity of the water is monitored to ensure it is within the required limits. After passing through the DF and MF units, water is temporarily stored in the filtrate tank.

The DF and MF units undergo regular backwash (using MF filtrate) with the used backwash fluid directed to the WTF Feed Pond. The MF unit also undergoes daily cleaning using sodium hypochlorite, sodium hydroxide (caustic soda) and sodium bisulphite to remove organic fouling and to maintain the hollow fibre membranes. Citric acid is also used to remove scale build-up when required. Spent cleaning fluids are directed to the WTF Feed Pond (buffer compartment).

5.2.1.3 Reverse Osmosis

RO desalination uses hydraulic pressure to overcome osmotic pressure and draw water through the RO membrane. Most dissolved salts and other trace elements are rejected by the membrane thereby generating two (2) separate product streams, treated CSG water and brine. The WTF operates at a recovery rate of approximately 80%.

Prior to entering the RO unit, water from the filtrate tank is batch dosed with DBNPA (2,2-dibromo-3-nitrilopropionamide) to reduce the propensity of feed water to cause biofouling of the RO membranes. Feed water to the RO is also adjusted for pH (if required) and dosed with antiscalant to reduce scale formation on the RO membranes. Feed water to the RO is monitored for conductivity, pH, temperature and oxygen reduction potential. If any of the limits for equipment protection are triggered, the RO feed water is recycled to the filtrate tank. Any overflows from the filtrate tank are directed to the WTF Feed Pond.

The pH and conductivity of the treated CSG water generated by the RO process is continuously monitored. Any treated CSG water which does not conform to the required water quality limits is automatically recycled to the filtrate tank. Brine is directed to a brine pond.

Periodic cleaning of the RO system is achieved using citric acid and sodium hydroxide with spent cleaning fluids directed to the WTF Feed Pond (buffer compartment).

5.2.1.4 Conditioning of treated CSG water

In order to ensure that the pH of treated CSG water meets the requirement for its end use, treated water from the RO system is blended with a small amount of filtrate from the MF unit. Continuous monitoring of pH and electrical conductivity between this dosing point and the downstream permeate tank will trigger an alarm in the event that either parameter exceeds a pre-defined alarm set-point.

Depending on the quality of water required by the end use, treated CSG water from the RO system will undergo one of the following types of additional treatment.

Treated CSG water for agricultural activities and river release

Treated CSG water to be used at the Pongamia Plantation for irrigation, on Australia Pacific LNG properties for stock watering, or to be released to Eurombah Creek, is dosed with calcium chloride downstream of the permeate tank.

Treated CSG water for aquifer injection

All treated CSG that is to be used by the Spring Gully aquifer injection facility undergoes a series of additional treatments at the PIP. These steps are outlined below and described in detail in the Spring Gully AIMP (CDN 11792487).

Disinfection

The first stage in the PIP treatment process is the disinfection of feed water by ultra-violet (UV) irradiation. As the permeate tank of the WTF is partially open to the atmosphere, UV irradiation is used to remove any biological particles that may have entered the treated CSG water following RO.

Cartridge filtration

Although the RO process removes all particulate matter, the potential exists for limited amounts of particulate matter to enter the treated CSG water while it is stored in the WTF Permeate Tank. Cartridge filtration removes this particulate matter and also serves to protect the downstream degasification membranes.

Degasification

The degasification membrane system utilises a vacuum pump and nitrogen gas sweep stream to lower the partial pressure of oxygen, drawing the oxygen out of solution from the feed water and across the membrane. The degasification membranes are designed to reduce dissolved oxygen concentrations to less than 50 µg/L.




Oxygen scavenger and corrosion inhibitor

An anti-oxidant corrosion inhibitor will be added to the permeate entering the injection bore.

Injectate monitoring

The degassed treated CSG water (injectate) is continuously analysed for pH, dissolved oxygen, electrical conductivity and temperature at the outlet of the PIP, prior to conveyance to the injection bores. Should the recorded parameters deviate from engineer-specified set points, automatic isolation valves will redirect the treated CSG water back to either the WTF Permeate Buffer Tank or Feed Pond.

5.2.1.5 Waste products from treatment processes

Waste products generated at the WTF and PIP primarily consist of:

Filtered solids and other chemical cleaning solutions from the WTF and PIP;

Contaminated water from chemical/dangerous goods storage areas, wash-down areas and stormwater collection system; and

Brine.

Waste products that are suitable for recycling will be directed to the WTF Feed Pond for subsequent treatment. Other wastes will be directed to brine ponds (see Section 5.3).




Note: Figure does not show recycle lines used to recirculate off-specification water

Figure 5-1: Simplified Process Flow Diagram of Treatment Steps at the WTF and PIP (Transition Stage and Future water strategy)




5.2.2 Treated CSG water use

In accordance with Section 3 of this CWMP, the future strategy for treated CSG water use in the SGDA, post the Transition Stage, consists of the following activities:

Project activities including dust suppression, construction activities and landscaping and revegetation;

Expansion Irrigation Scheme; and

Aquifer injection into the Precipice Sandstone.

The following sub-sections describe the infrastructure and operation of each of these components. The current authorised release to Eurombah Creek, comprising a discharge line from the permeate export tank, considered part of the CSG water management strategy in the Transition Stage, will be undertaken in accordance with the requirements of the Spring Gully EA.

The Spring Gully Water Quality Monitoring Program (WQMP) (CDN 8600568), refer to Appendix B, documents the compliance water quality monitoring requirements associated with the current approvals – refer to Table 5-2 below. The update of the WQMP will be undertaken post the Transition Stage to reflect cessation of discharge to Eurombah Creek, as it is a key operational document.

Table 5-2: Summary of Approvals Governing the Use of Treated CSG Water in the SGDA

CSG Water Use Activity Approval

Use of CSG water and/or treated CSG water for project activities

General BUA

Use of treated CSG water for irrigation Irrigation General BUA

Use of treated CSG water for aquifer injection Spring Gully EA referencing the Spring Gully AIMP

EPBC 2017/7881 (subject to approved decision)

5.2.2.1 Project activities

As described in Section 5.1.3, where it is compatible with the requirements of the particular project activity and where it can be conducted in accordance with the General BUA, untreated CSG water will be preferentially used to support project activities. In circumstances where a higher quality of water is required, treated CSG water will be used in accordance with the General BUA. Project activities that could use treated CSG water include:

General construction activities such as:

Well drilling, workovers and completions;

Hydro-testing of CSG water gathering network;

Facility construction;

Dust suppression for construction and maintenance activities (subject to internal approval and adequate controls); and

Landscaping and revegetation/rehabilitation.

Water to be used for these activities will be sourced from the gathering network/WTF/permeate supply network.

No additional infrastructure is required to undertake this activity.

5.2.2.2 Expansion Irrigation Scheme

The Expansion Irrigation Scheme will comprise (in addition to the WTF and dispatch pumps upgrade):

Existing 285 ha Pongamia plantation drip irrigation system fed via offtake pipeline from the WTF;

~20km pipeline (with tie in to the existing Pongamia irrigation pipeline) to a storage dam;

Storage dam with capacity of up to 350 ML;

Irrigation pumps; and

Irrigation plots (as required) to avoid excess permeate.




5.2.2.3 Aquifer injection

The Spring Gully aquifer injection scheme commenced operation by Q1 2015 into one (1) of the three (3) injection bores with the remaining two (2) bores commissioned in Q3 2015. The scheme is authorised to inject up to 8.1 ML/d of treated CSG water from the PIP for injection into the Precipice Sandstone. Table 5-3 describes the location of this infrastructure.

Table 5-3: Location of Injection Bores and Monitoring Bores

Bore ID Longitude (GDA94)

Latitude (GDA94) Description

DRP-WI-1 149.07109 -26.000209 Injection bore (previously used for trial)

DRP-WI-2 149.07068 -26.000305 Injection bore

DRP-WI-3 149.07136 -25.999970 Injection bore

DMP01 149.07136 -26.000446 Monitoring bore

DMH01 149.07101 -26.000497 Monitoring bore

The process flow diagram of the PIP is presented in Figure 5-2.

Figure 5-2: PIP Process Flow Diagram

Water quality parameters are monitored at several inline points within the WTF and PIP to ensure that the quality of water to be injected remains within engineer-specified control points that are commensurate with conditions of the Spring Gully EA, and to ensure that the WTF and PIP are operating within their respective design specifications.

A programmable logic controller (PLC) measures each of the inline sensors continuously to ensure rapid response to off-specification treated CSG water. Data is stored by a supervisory control and data acquisition (SCADA) system and can be retrieved for interpretation or reporting.

Table 5-4 summarises the PLC set point limit levels for the aquifer injection scheme which align to the conditions of the Spring Gully EA. PLC operational targets and alarm levels will also be defined. The operational target is the preferred value for injection whereas alarm levels advise the operator that the water quality is outside of the target range. The limit level represents a control point that accords with




the Spring Gully EA and that if breached, will trigger the automatic cessation of injection until the parameter returns to within the acceptable range.

Table 5-4: Aquifer Injection PLC Set Points

Parameter Unit Limit Level

Electrical Conductivity µS/cm 460

Dissolved Oxygen ppb 500

Total Dissolved Solids mg/L 300

pH pH unit 6.5 – 8.5

Wellhead Pressure kPa 3,700

A regular maintenance program has been established to ensure efficient operation of the injection bores. This will include consideration of construction materials and their mechanical integrity, the injection pumps, instrumentation and the monitoring bores and related infrastructure. Each of these component pieces of infrastructure will have specific maintenance requirements that will be addressed on a scheduled basis. Unscheduled maintenance will also be conducted as required based on monitored performance.

5.3 Brine and salt management scheme (Encapsulation)

The preferred brine and salt management scheme comprises storage of brine in ponds, utilising solar evaporation for the concentration of brine, followed by thermal crystallisation to produce a solid salt product suitable for containment in a RWF. A conceptual overview of the scheme’s key processes is shown in Figure 5-3, which incorporates:

Storage and solar evaporation of brine in brine ponds – brine produced by the WTF (TDS circa 30 g/L, Table 2-3) is transferred into brine ponds located in close proximity to the WTF for storage. Evaporation of water from the brine increases its salinity until crystallisation commences (at circa 250 g/kg of brine).

Regional aggregation of brine – the concentrated brine is transferred by aggregation pipeline to the regional location where it will be crystallised and encapsulated in a regulated waste facility (RWF).

Brine crystallisation to solid salt – two regional crystallisers and RWF are proposed, one for each of the east (Talinga and Condabri) and west (Reedy Creek and Spring Gully) regions. The crystallisation process is anticipated to be a thermal process, with solid salts transferred to the RWF.

Salt encapsulation in RWF – the RWF will receive salt in a staged approach, resulting in operational and completed cells, which reduces the risk of dissolution of stored salt due to rainfall and exposure of the surface to wind-borne salt transport. The RWF will be designed and operated in accordance with applicable legislation and guidelines, and is anticipated to be located within the footprint of decommissioned brine ponds.

The brine crystalliser and encapsulation facility infrastructure is anticipated to be operational in approximately 20 years time, which allows time for further refinement of this option. Elements such as equipment sizing, timing and precise location can be refined as more certainty is gained over the amount of water and salt that will be produced by Australia Pacific LNG.




Figure 5-3: Overview of Processes and Operations for RWF

5.3.1 Brine ponds

Brine and high salinity WTF effluents produced during the RO desalination of CSG water is stored in ponds designed, constructed and operated in accordance with the Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2013) and regulatory requirements of relevant approvals.

The brine storage capacity within the SGDA is 2047.9 ML based on the TOWL, comprising 5 dams (i.e. Pond B and Pond C Cells 1-4). Level control gauge labels are installed in each pond to identify the mandatory reporting level and spillway level.

Based on the site water balance modelling, an additional brine dam may be required with a capacity of up to 400 ML due to predicted increased water volumes over the project life. Preliminary siting location assessments to date have identified any future dams are likely to be in close proximity to existing Pond C. The requirement for brine storage is continually reviewed in conjunction with the anticipated water production and field development plans.

As built details of the current brine (regulated) dams are available in the Spring Gully Regulated Dam Register.

5.3.2 Regional Brine Aggregation Pipelines

The preferred scheme requires a regional cross-tenure pipeline is required between the Spring Gully and Reedy Creek WTFs for transfer and aggregation of brine to a single regional crystallisation and encapsulation facility in the west. The alignment of the pipeline is intended to follow existing pipeline and infrastructure easements currently connecting the facilities for gas and/or produced CSG water transfer, where available.

Various materials have been considered for the brine aggregation pipelines and the following key issues are intended to be considered when selecting the preferred material:

Minimise risk of leakage and accommodate design and transient pressures.




Have the ability to be cleaned to reduce risk of blockage, and

Have ability to incorporate control valves, gates, and meters.

5.3.3 Brine Crystalliser

To produce a solid salt suitable for encapsulation, a final dewatering process will be undertaken. The brine crystalliser core process will be thermal and will convert the high salinity brine to solid salt for transfer by conveyor and/or truck to the encapsulation facility.

5.3.4 Salt Encapsulation in a RWF

Solid salt will be encapsulated in a RWF involving proven technologies that are commercially available and represent an evidence-based method of safely containing and storing waste. The current intention is to locate the RWF within the footprint of existing brine ponds at Reedy Creek WTF.

6. Existing Environment

This section describes the existing environment of the SGDA with particular focus on those aspects of the environment that may interact with the CSG water management scheme.

6.1 Climate

Climate data is recorded by the Australian Government Bureau of Meteorology (BoM) at Roma Airport (65 km to the southwest of the WTF) and Injune Post Office (53 km to the northwest) Based on data recorded at these stations, the climate of the SGDA can be summarised as follows, and as shown in Figure 6-1:

Sub-tropical and semi-arid with warm and wetter summers and relatively mild and drier winters;

Average daily maximum temperatures ranging between 20°C in winter and 33°C in summer;

Average daily minimum temperatures ranging between 3°C in winter and 20°C in summer;

Average monthly rainfall ranging between 25 mm in winter and 89 mm in summer; and

Average monthly evaporation significantly exceeds rainfall in all months. It varies seasonally between 96 mm in winter and 319 mm in summer.

Note: Mean maximum and minimum temperature and mean monthly rainfall recorded at Injune Post Office (BoM Site Number 043015) 53 km northwest of the SGWTF. Mean monthly evaporation recorded at Roma Airport (BoM Site Number 43091) 65 km southwest of the SGWTF.

Figure 6-1: Regional Climate

The SGDA is in a portion of southern Queensland where magnitude of rainfall water and evaporation water loss is unbalanced (i.e. annual evaporation exceeds annual rainfall). The SGDA experiences approximately 630 mm of rain per year on average and the average evaporation rate is approximately




2,000 mm per year. As such, the SGDA experiences approximately 1,370 mm of net evaporation per annum. Variability in terrain across the SGDA will contribute to some variability in local climate.

6.2 Land

6.2.1 Topography and geomorphology

A topography, geomorphology and soil assessment was conducted by Golder Associates (Golder, 2013) to provide a desktop and ground truthing assessment of the soil resources and values within the SGDA project area.

The topography across the SGDA project area consists predominantly of rises and undulating plains on the southern half and eastern third of the SGDA project area with low hills leading to dissected sandstone hills towards the north. The hills have slopes generally in the order of 10% and up to more than 20%. Major topographical features in the region include Robinson Gorge, to the northeast of the development area, and Expedition Range, to the northwest. The development area lies within the Brigalow Belt Bioregion.

There are also broadly spaced rivers and creeks flowing in a general easterly direction across the project area. Principal watercourses consist of:

Dawson River

Scotts Creek

Eurombah Creek, and

Several creeks that originate to the south of the SGDA project area and flow north-easterly across plains and channels to join Eurombah Creek.

The landform categories applicable to the SGDA project area are as follows:

Dissected plateaus;

Plateaus and low hills;

Rises and undulating plains; and

Level to gently undulating plains.

The predominant landforms are rises and undulating plains with level to gently undulating plains along the water courses.

6.2.2 Geology and soils

The SGDA lies within the Surat Basin, part of the GAB, which in turn, overlies the Bowen Basin. The sediments of these basins were deposited as fluvio-deltaic packages in coastal plains or shallow marine setting and contain significant and economic coal beds. The basins are separated by a major unconformity, with the Bowen Basin sediments lying below the contact.

The SGDA lies close to the boundary between the surface outcrop of the Bowen and Surat Basins. Its surface geology is dominated by rocks of Middle Jurassic Hutton Sandstone and the Late Jurassic Injune Creek Group4. Soil types vary considerably but are primarily comprised of texture-contrast soils and cracking clays with a high proportion of fines. The shallow texture-contrast soils are typically used for grazing while stony shallow soils are more frequently associated with forestry activities or grazing of native pastures. Cracking and non-cracking clays (particularly those of alluvial origin) are the most productive soils in the development area and are used for dryland cropping as well as improved pasture.

A number of detailed assessments of soils within the SGDA has been undertaken. This program of assessment has involved the collection of many soil samples that have been characterised and grouped as individual Australian Soil Classification Key Soil Orders (KSO) or KSO associations mapped at scales of 1:15,000 to 1:30,000 consistent with the Soil Mapping Units mapped at approximately 1:1,500,000. In summary, Dermosol/Vertosol and Tenosol/Sodosol and Sodosols are the main soil types of the SGDA.

4 See Taroom 1:250,000 Geological Map (Sheet SG/55-8) and the Roma 1:250,000 Geological Map (Sheet SG/55-12)




6.2.3 Land use

As defined by the Queensland Land Use Mapping Program5 and as shown in Table 6-1, the dominant land use in the SGDA is livestock grazing (88.5%). More localised uses include production forestry (7.8%) and non-irrigated cropping (3.5%).

Woodland and forests are predominantly found in the northern half of the development although dense vegetation is found along the banks of watercourses and in other localised pockets scattered across the development area. The Hallett, Stephenton and Belington Hut State Forests lie within ATP 592 in the far north of the development area. The Expedition Range National Park lies outside the development area to the northwest of ATP 592.

Most land tenure is freehold. A network of existing minor public roads and tracks pass through the development area although no major roads are present. There are no townships within the development area although rural homesteads are scattered across its extent.

Approximately 60% (156,250 ha) of the SGDA is classified by Queensland Government mapping as either Class A or Class B Good Quality Agricultural Land, with these areas typically found on the undulating plains of the south and east of the development area. Queensland Government mapping also identifies potential strategic cropping land within the development area, triggered as the Strategic Cropping Area under the Regional Planning Interests Act 2014 (Qld).

Table 6-1: Land Use in the SGDA

Land Use Category Land within SGDA (ha) % of SGDA

Livestock grazing 226,499 88.5

Production forestry 19,884 7.8

Cropping 9,034 3.5

Reservoir/dam 294 0.11

Lake 101 0.04

Transport and communication 38 0.01

Utilities 34 0.01

Mining 27 0.01

Residential 13 < 0.01

Intensive animal production 6 < 0.01

Irrigated perennial horticulture 0.01 < 0.01

Other minimal use 48 0.02

TOTAL 256,979 100

Data source: http://www.qld.gov.au/environment/land/vegetation/mapping/qlump/

6.3 Groundwater

6.3.1 Hydrogeology

The hydrostratigraphic sequence of the SGDA in the vicinity of the WTF is presented in

5 See http://www.qld.gov.au/environment/land/vegetation/mapping/qlump/




Table 6-2: Hydrostratigraphic Sequence . It shows that aquifers are typically separated by aquitards. For example:

The Hutton Sandstone aquifer outcrops in the development area and is underlain by the Evergreen Formation aquitard;

The Boxvale Sandstone Member aquifer lies between the Evergreen Formation and Basal Evergreen Formation aquitards; and

The Precipice Sandstone aquifer (the basal formation of the Surat Basin) is overlain by the Basal Evergreen Formation and overlies the Rewan Formation aquitard. The Rewan Formation aquitard separates the Precipice Sandstone from the underlying Permian age Bandanna Formation, the target CSG reservoir in the SGDA.

No large regional scale faults are mapped in the immediate vicinity of the WTF (the Hutton-Wallumbilla Fault lies approximately 25 km to the west). Numerous small scale faults have been interpreted from seismic data however none of these faults have been interpreted to be vertically continuous from the Precipice Sandstone through to any other aquifer.

The SGDA is located to the immediate north of a regional groundwater divide oriented northwest-southeast. Groundwater flow in the Precipice Sandstone is expected to be towards the northeast.

6.3.2 Groundwater quality

Groundwater quality has been sampled at monitoring and water supply bores targeting the Precipice Sandstone in the vicinity of the WTF. Selected laboratory results prior to the start of the injection trial are presented in Error! Reference source not found.. To calculate the median and 95th percentile, values below the detection limit were set at the detection limit, hence the statistics presented represent conservative values.

Precipice Sandstone groundwater is strongly sodium dominant, with a higher bicarbonate concentration than chloride. In comparison to the Australian Drinking Water Guidelines (NHMRC 2011) (ADWG), the majority of water quality parameters lie within suitable ranges for potable use. Exceptions are recorded for iron, manganese and lead, which all recorded exceedances of the ADWG aesthetic limit.

6.3.3 Groundwater use

The Spring Gully AIMP includes an assessment of landholder bores in the SGDA that source water from the Precipice Sandstone. Of those water supply bores that have the potential to lie within the hydraulic impact zone of the Spring Gully aquifer injection scheme (listed in Table 6-4), all but the Spring Gully camp bore uses Precipice Sandstone groundwater for the watering of stock.

6.3.4 Groundwater – surface water interaction

Recharge of groundwater in the region mainly occurs via the infiltration of rainfall at intake beds exposed in outcrops or sub-crops along the elevated northern and eastern margins of the Surat Basin. Infiltration of rainfall may occur directly into outcropping sandstone aquifers, through contributions from losing reaches of watercourses, or by percolation through unconsolidated sediments that overlie the aquifers.

The Underground Water Impact Report for the Surat Cumulative Management Area (QWC, 2012) (UWIR) reports that sections of Eurombah Creek in the vicinity of the WTF are fed by groundwater from the Hutton Sandstone. The National Atlas of Groundwater Dependent Ecosystems (NWC, 2012) identifies Eurombah Creek and two unnamed riverine wetlands as having high potential for groundwater interaction in the vicinity of the WTF.

6.3.5 Groundwater dependent ecosystems

The UWIR (2016) identifies no springs sourced in the vicinity of the SGWTF, although Eurombah Creek may be groundwater fed in parts.

The Scotts Creek spring complex lies within the Spring Gully development area, approximately 25km to the northeast of the WTF. OGIA (2015a) identifies the source aquifer to be the Hutton Sandstone. During a terrestrial ecology assessment commissioned by Australia Pacific LNG, salt pipewort, which is listed as endangered under the EPBC Act was found at these springs. Since the Scott’s Creek spring complex is a discharge spring sourced from a GAB aquifer, the ecological communities at these springs are considered as Matters of National Environmental Significance (MNES) under the EPBC Act.

The Lucky Last spring complex hosts MNES, and is sourced from the Boxvale Sandstone member (OGIA 2015b). It is not within the SGDA and is approximately 38km north-northwest of the WTF. The Abyss and Spring Rock Creek complexes, also outside of the SGDA are believed to be sourced from




the Precipice Sandstone. Abyss is in close proximity to Lucky Last, whereas Spring Rock Creek is approximately 4km to the north of Lucky Last. Abyss hosts MNES but Spring Rock Creek does not (OGIA 2015c).




Table 6-2: Hydrostratigraphic Sequence

Province Age Spring Gully Stratigraphy Aquifer/Aquitard S

ura

t B

asin

Jura

ssi

c

Inju

ne

Cre

ek

Gro

up

Walloon Coal Measures Minor coal and sandstone Aquifers with siltstone and mudstone Aquitards (very thin or not present at Spring Gully)

Bu

nd

amb

a G

rou

p Hutton Sandstone Aquifer - outcropping formation at Spring Gully

Evergreen Formation Aquitard

Boxvale Sandstone Member Aquifer

Basal Evergreen Formation Aquitard

Precipice Sandstone Major Aquifer

Bo

wen

Bas

in

Tri

assi

c

Moolayember Formation Aquitard (not present at Spring Gully)

Clematis Group Sandstones Aquifer (not present at Spring Gully)

Rewan Group Upper Aquitard underlain by variable minor Aquifer

Per

mia

n

Bla

ckw

ater

G

rou

p Bandanna Formation

(Coal Measures) Minor coal and sandstone Aquifers with siltstone and mudstone Aquitards

Kaloola Member Aquitard

Up

per

Bac

k C

k G

rou

p Black Alley Shale Aquitard

Mantuan Formation Mixed Aquitards and very minor Aquifers

Upper Tinowon Formation Aquitard

Lower Tinowon Formation Mixed Aquitards and very minor Aquifers

Ingelara Formation Aquitard

Lo

wer

Bac

k C

reek

Gro

up

Aldebaran Sandstone Minor Aquifer

Reids Dome Beds Aquitard

Bas

emen

t

Dev

on

ian

Timbury Hills Formation Aquitard




Table 6-3: Precipice Sandstone Groundwater Quality

Parameter Units

ADWG Guideline Value Range Median

95th Percentile

pH pH unit 6.5 - 8.5 A 6.5 - 8.5 7.2 8.3

Electrical conductivity µS/cm - 134 - 281 191 245

Total dissolved solids mg/L 600 A 78 - 109 90 106

Total suspended solids mg/L - <1 - 41 5 24

Total organic carbon mg/L - <1 1 1

Fluoride mg/L 1.5 H <0.1 - <0.5 0.1 0.3

Arsenic (total) mg/L 0.01 H <0.001 - <0.005 0.001 0.003

Boron (total) mg/L 4 H <0.05 - 0.06 0.05 0.06

Barium (total) mg/L 2 H 0.01 - 0.35 0.07 0.25

Copper (total) mg/L 2 H, 1 A 0.001 - 0.5 0.005 0.3

Iron mg/L 0.3 A 0.79 - 7.62 0.92 7.46

Manganese mg/L 0.5 H, 0.1 A 0.01 - 0.21 0.051 0.21

Lead mg/L 0.01 H <0.001 - 0.02 0.004 0.02

Strontium (total) mg/L - 0.01 - 0.2 0.09 0.2

Nitrogen (total oxidised) mg/L - <0.01 - 0.06 0.02 0.04

Phosphorus mg/L - <0.01 - 0.1 0.05 0.09

Gross alpha Bq/L - <0.2 0.2 0.2

Gross beta activity - 40K Bq/L - 0.2 0.2 0.2

Table Notes H ADWG guideline value for health A ADWG guideline value for aesthetic quality

Shaded cells indicate exceedance of either a health or aesthetic ADWG guideline value.

Table 6-4: Landholder Bores and Water Uses

Ref. Bore ID Distance from SGWTF (km) Primary Water Use

1 Australia Pacific LNG Spring Gully Camp bore

5.6 Water supply to Spring Gully

camp

2 Spring Gully-PB1 28.6 Monitoring bore

3 Spring Gully-PB3 10.2 Monitoring bore

4 Strathblane-WB1-B 13.3 Stock watering

5 RN58623 14.6 Stock watering




6.4 Surface water

The SGDA lies within the Upper Dawson River sub-basin of the Fitzroy Catchment.

The majority of the development area is drained by Eurombah Creek and its tributaries (predominantly Durham Creek, Barton Creek and Kangaroo Creek). Eurombah Creek flows in an easterly to north-easterly direction through the centre of the development area, joining the Dawson River close to Taroom, approximately 60 km to the northeast of the development area boundary. The Dawson River flows from west to east approximately 30 km northeast of the WTF and through the far north of the development area.

Eurombah Creek is ephemeral and between flow events exists as a series of shallow and disconnected waterholes that may persist through the dry season. The channel of Eurombah Creek is typically well incised, with relatively steep banks approximately 10 m in height. The low flow channel width is about 8 m and the channel bed is generally comprised of clays and silts, with some sand bars, clear of vegetation, with rock outcrops and/or embedded boulders.




The vast majority of watercourse reaches within the SGDA are defined by DEHP (2011) as having a moderately disturbed ecosystem condition. High ecological value (HEV) areas, where the management intent is to achieve an effectively unmodified waterway condition, are restricted to a short reach of Commissioner Creek (approximately 20 km northeast but not downstream of the WTF) (HEVa2144) and a larger area (HEVa2145), located adjacent to the Dawson River in the far north of the development area (and upstream of the Eurombah Creek confluence).

6.4.1 Hydrology

Flow on Eurombah Creek is recorded by a DNRM gauge at Brookfield (130376A), approximately 50 km downstream of the point at which treated CSG water is intermittently released to Eastern Gully. Eurombah Creek is ungauged upstream of this location and so an estimate of flow at the Eastern Gully confluence has been made using the Australian Water Balance Model (AWBM) rainfall-runoff model. The results show that for a median rainfall year, flows in excess of 86 ML/d (equivalent to 1 m3sec-1) can be expected to occur on approximately 14 days in a year. Annual flow estimates indicate a flow of approximately 10,000 ML for a median rainfall year (see Table 6-5). Of the annual total flow, between 400 ML and 700 ML could be lost due to seepage and evaporation before Eurombah Creek crosses the eastern boundary of the SGDA (see the Eurombah Creek REMP for further details).

Analysis by Joo et al. (2005) suggests that annual flow through the Eurombah Creek system contributes approximately 0.1% to the annual flow of the Dawson River and less than 0.02% to the annual flow of the Fitzroy River.

Table 6-5: Estimated Annual Flows in Eurombah Creek at the Eastern Gully Confluence

Type of Rainfall Year Annual Flow (ML)

10th percentile (very dry year) 2,200

25th percentile (dry year) 4,000

50th percentile (‘normal’ year) 10,000

75th percentile (wet year) 30,000

90th percentile (very wet year) 56,000

The flow duration curve for the DNRM gauge on Eurombah Creek at Brookfield (130376A) is presented in Figure 6-2. The flow data from this gauging station is classified as ‘Poor’ by DNRM, meaning the data has been validated and is the best available at the time, but that results should be interpreted with caution. It suggests that no flows have occurred for around half the time since the gauge commenced operation in November 2011. It should be noted that the treated CSG water release scheme was operating during this period.

Figure 6-3 presents a time series of the gauged data and shows that the hydrology of Eurombah Creek is characterised by episodic flow events in response rainfall. Five (5) events in the last three (3) years have recorded mean daily flows of approximately 1,000 ML/d or greater. Typically, the time to peak and recession of these flow events was rapid however more prolonged periods of flow have occurred in the recent past. Over a 72 day period between January and April 2012, mean daily flow was maintained above 10 ML/d and reached greater than 10,000 ML/d. Releases of treated CSG water were intermittent during this period, occurring on 50 days at an average rate of 3.5 ML/d and a maximum rate of 6.1 ML/d.




Figure 6-2: Eurombah Creek at Brookfield – Daily Flow Duration Curve

Figure 6-3: Time Series of Daily Flow, Rainfall and Releases




6.4.2 Surface water quality

As a component of the Eurombah Creek REMP (refer to Appendix C), Australia Pacific LNG has conducted sampling of water quality on Eurombah Creek since 2011. The results of samples taken upstream of the treated CSG water release point (and therefore reflective of background conditions) are presented in Error! Reference source not found.. They show that the water quality of Eurombah Creek is dominated by calcium, sodium, bicarbonate and chloride ions.

Pre-release water quality (and aquatic habitat) data is available in the Spring Gully Coal Seam Gas Field Assessment of Discharging Reverse Osmosis Permeate to Eurombah Creek (EECO, 2007) report confirms in the period between 2003 to 2006, Eurombah Creek is highly turbid, has high pH and high concentrations of nitrate, aluminium and copper and at times, concentrations of sodium, chloride and Total Dissolved Solids can reach high levels.

Annual reporting of the surface water quality of Eurombah Creek is undertaken, with latest available data available in the 2016 Annual Report (CDN 13947082).

6.4.3 Surface water use

Surface water entitlements in the Fitzroy River Basin are controlled by the Queensland Government through the implementation of the Fitzroy Basin Resource Operations Plan (DEHP 2013). Within the Fitzroy Basin, supplemented water (that water allocated through a regulated system) is delivered through five (5) water supply schemes. The closest of these to the SGDA is the Dawson Valley Water Supply Scheme. This scheme commences at the upstream limit of Glebe Weir (around 200 km downstream of the WTF) and extends to around 18 km upstream of the Fitzroy River junction. No uses of surface water to support food production for human consumers, drinking water or industrial use are known to exist along Eurombah Creek, with EVs updated accordingly in the Spring Gully REMP.

6.4.4 Aquatic habitat

The Eurombah Creek catchment is characterised by meandering channels with some areas of erosion coinciding with riparian vegetation clearance, grazing and trampling by cattle. Surveys of Eurombah Creek conducted in support of the Eurombah Creek REMP indicate that the aquatic habitat condition of sites upstream of the treated CSG water release point are generally of a moderate condition. Outside of flow events, aquatic habitat is limited to pools. There is little overhanging or trailing terrestrial vegetation. Extensive beds of macrophytes have recently been recorded (Boobook, 2017). Partially and fully submerged dead trees and branches are present in places.

6.4.5 Aquatic ecology

An aquatic ecology assessment of the SGDA comprising desktop research and targeted field surveys was conducted in 2012 (frc environmental, 2013). Its key findings were as follows:

Aquatic ecological values are low to moderate and dictated primarily by the ephemeral nature of many of the regional watercourses. Agricultural development has significantly altered the water quality and physical characteristics of aquatic habitat;

Watercourses are generally characterised by cleared riparian vegetation, bank erosion, low habitat diversion, invasion of weed species, poor water quality and sedimentation;

Watercourses typically have a low to moderate biodiversity and generally support only those fish and macroinvertebrate species that are tolerant of varying and often harsh conditions;

The most significant watercourses (such as the Dawson River and Eurombah Creek), offer more stable habitat and as a consequence, have a higher ecological value but still exist in a slightly to moderately disturbed condition;

Wetlands and springs are characterised by slightly to moderately disturbed conditions as a result of cattle damage and weed invasion; and

There are no wetlands of national significance within the development area. The nationally significant Palm Tree and Robinson Creeks complex lies approximately 40 km downstream of the development area.

The descriptions of aquatic ecology are provided in the Spring Gully REMP (refer to Appendix C) with the 2016 Annual Report (CDN: 13947082) assessing no discernible negative impacts to date.

6.4.6 Environmentally Sensitive Areas

Queensland Government mapping indicates the presence of environmentally sensitive areas (ESAs) related to water in the SGDA, namely Endangered and Of Concern Regional Ecosystems mapped adjacent to watercourses.




Australia Pacific LNG has an ongoing program for ground-truthing ESAs. The Spring Gully Environmental Constraints Planning and Field Development Protocol (Q-8200-15-MP-1157) has been prepared for expansion of the existing SGDA.

6.4.7 Matters of National Environmental Significance

Ongoing periodic reviews of relevant MNES have occurred in relation to the SGDA having regard to current and future development and operations.

A desktop assessment conducted as part of the aquatic ecology assessment (frc environmental 2013) identified the following four (4) species listed under the EPBC Act as having the potential to occur in the SGDA.

Fitzroy River turtle (Rheodytes leukops);

Murray cod (Maccullochella peelii);

Salt pipewort (Eriocaulon carsonii); and

Community of native species dependent on natural discharge of groundwater from the GAB.

Salt pipewort and the community of species dependent on groundwater from the GAB (both listed as endangered under the EPBC Act), were recorded during a terrestrial ecology assessment.

Subsequent to the frc environmental 2013 assessment, additional MNES reviews has identified the:

Actual occurrence of the White-Throated Snapping Turtle (WTST) (Elseya albagula), listed under the EPBC Act as critically endangered, and identified by Boobook Ecological Consulting (2017) as an important population.

Potential presence of the Curlew Sandpiper and Australian Painted Snipe, however Eurombah Creek is likely to represent, at best, marginal habitat.

6.4.7.1 White Throated Snapping Turtle

The White-throated Snapping Turtle is endemic to Queensland, being found only in the Burnett, Marty and Fitzroy River and their associated tributaries (DoEE 2014).

Boobook (2017) reported:

One or more WTST were observed at seventeen (17) sites, or 38.6% of surveyed sites within Eurombah Creek

Aquatic and terrestrial (nesting) habitat within the survey area.

7. Environmental Values and Water Quality Objectives

This section of the CWMP identifies and describes the environmental values (EV) of the SGDA. For surface water and groundwater EVs, it also identifies associated Water Quality Objectives (WQOs) relevant based on the implemented CSG water management strategy.

The EVs of Queensland waters are specified in supporting documents to the Environmental Protection (Water) Policy 2009 (Qld) (EPP Water) for the Dawson River Sub-Basin. Table 7-1 presents the surface water and groundwater EVs for the SGDA as defined by DEHP (2011).

Table 7-1: Environmental Values of Water

Environmental Value Upper Dawson Southern Tributaries – developed areas

Surface Water Groundwater

Aquatic ecosystems Irrigation* Farm supply/use Stock water Aquaculture Human Consumer*




Environmental Value Upper Dawson Southern Tributaries – developed areas

Surface Water Groundwater

Primary Recreation Secondary Recreation Visual Recreation Drinking Water Industrial Use

Cultural and Spiritual Values *A review of site specific EVs does not identify Irrigation and Human Consumer EVs as applicable (excluding the proposed Expansion Irrigation Scheme).

To protect site specific EVs listed in Table 7-1, DEHP (2011) has specified sub-regional water quality guideline values or cited separate guideline documents that should be used to derive WQOs for effective management. In the case of the aquatic ecosystem EV, these WQOs vary depending on the condition (and associated management intent) of the waters in question. Waters of the SGDA are considered to be ‘moderately disturbed’ and therefore the management intent (as defined by EPP Water) is to ensure the biological integrity of an aquatic ecosystem that is adversely affected by human activity to a relatively small but measurable degree.

In order to ensure the protection of those EVs that have the potential to be affected by CSG water management, Australia Pacific LNG has adopted WQOs for the following two (2) environments:

Surface water of Eurombah Creek; and

Precipice Sandstone groundwater (in association with the Spring Gully aquifer injection scheme).

The derivation of WQOs for these two (2) environments is described in detail in the Eurombah Creek REMP (refer to Appendix C) and Spring Gully AIMP respectively.

HEV areas, where the management intent is to achieve an effectively unmodified or highly valued condition, are restricted to a short reach of Commissioner Creek (approximately 20 km northeast but not downstream of the WTF) and an area adjacent to the Dawson River in the north of the SGDA. It is considered that the Spring Gully CSG water management scheme will not impact these areas.

In addition to the WQOs, Australia Pacific LNG has adopted a number of other criteria against which it will monitor the ongoing effectiveness of CSG water management. These management criteria are outlined in Section 9 of this CWMP.

8. Risks, Potential Impacts and Management

Australia Pacific LNG will implement the CSG water management scheme for the SGDA in accordance with relevant approvals in order to ensure the protection and maintenance of all relevant EVs. A complete assessment of compliance of the CSG water management scheme for each annual return period is provided to DEHP.

An adaptive management process is in effect for SGDA water operations which is a structured, iterative process of decision-making with a focus on the progressive reduction of uncertainty over time. It has been implemented through a modelling-monitoring-management approach whereby each component is used to inform and refine the others. Should the monitoring and modelling indicate an increase in risk to potential receptors due to implementation of the Transition Stage or future CSG water management scheme, the adequacy of the monitoring can be reviewed to assist in the management of that risk.

This section of the CWMP presents the outcomes of an environmental risk assessment conducted to ensure that all risks to EVs from CSG water management in the SGDA are appropriately controlled.




8.1 Risk assessment process

Australia Pacific LNG is committed to the continual and effective management of risk and implements a risk management process to ensure that:

Systems are in place to identify risks to the extent that is reasonably practicable;

The potential impacts of identified risks are understood and that limits are set to ensure their appropriate management;

Responsibilities for risk management are delegated to appropriate persons;

Assurance is provided as to the effectiveness of the risk management system and its associated risk controls; and

Any material changes to risk levels are monitored and acted upon accordingly.

To achieve these aims, for all CSG water management activities, Australia Pacific LNG conducted a comprehensive risk assessment when developing the current CSG water management strategy that included the steps outlined in Figure 8-1 below, in accordance with International Standard ISO 31000 – Risk Management.

Figure 8-1: Risk Assessment Process

Risks associated with the operation of the CSG water management scheme have been considered for the lifetime of the SGDA. For each identified risk, the Australia Pacific LNG risk matrix (Figure 8-2) was used to assign a consequence and likelihood rating assuming existing controls are in place deriving a risk level of a five-point scale (Low to Extreme).

‘Low’ level risks and some ‘Medium’ level risks (of acceptably low severity), are considered to be appropriately mitigated by existing controls without the need for further treatment. For all other risks, additional mitigation measures must be considered and treatment plans prepared and approved. For ‘Extreme’ risks, a treatment plan is prepared and implemented immediately.

The following sub-sections summarise the outcomes of the assessment of risks to EVs associated with operation of the CSG water management scheme for the SGDA.




Environmental requirements associated with the construction of CSG water management infrastructure are discussed in the Project Construction Environment Management Plan (Q-LNG01-15-MP-1001) and the accompanying Detailed Construction Environmental Management Plan (Q-LNG01-15-MP-0144). Issues to be considered and managed during the decommissioning, rehabilitation and remediation of CSG water management infrastructure are discussed in the Spring Gully Development Area Rehabilitation Plan (CDN 12883952).

LIKELIHOOD RATING

1

Remote

2 Highly

Unlikely

3 Unlikely

4 Possible

5 Likely

6 Almost Certain

CO

NS

EQ

UE

NC

E R

AT

ING

6 Catastrophi

c H H S S E E

5 Critical M M H S S E

4 Major M M M H S S

3 Serious L M M M H S

2 Moderate L L M M M H

1 Minor L L L M M M

Notes: L = Low, M = Medium, H = High, S = Severe, E = Extreme.

Figure 8-2: Risk Matrix

8.2 Untreated CSG water management scheme

The risks and existing controls associated with the untreated CSG water management scheme of the SGDA are summarised in Table 8-1 following.

8.2.1 CSG water gathering network

Risks to EVs associated with the operation of the CSG water gathering network are limited to the potential for a loss of pipeline integrity to lead to the uncontrolled release of CSG water. Table 8-1 shows that existing design, operating and monitoring controls ensure that the likelihood of this risk occurring is ‘Highly Unlikely’ and that in such an event, its consequence would be ‘Minor’. The overall risk level is therefore considered ‘Low’.

8.2.2 CSG water storage

All dams are assessed as significant or high consequence structures will be designed, constructed, operated, maintained and decommissioned in accordance with the current DEHP Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2016 or as updated). Note: The dams constructed for the initial WTF and gathering network operation, including Spring Gully Pond A (now decommissioned), the Taloona dam (under rehabilitation) and the Strathblane WGS were designed and constructed in accordance with the applicable regulation of the time or transitioned to compliance under an approved program.

Table 8-1 presents risks associated with the operation of CSG water storages. It shows that existing control measures are sufficient to ensure that all risks are ranked as ‘Low’, based on the decommissioning of dams not constructed with an impermeable liner. Routine inspections and maintenance tasks and a detailed annual inspection by a suitably qualified ‘dam’ engineer will be performed to ensure that the condition and operation of CSG water storages meet the relevant performance criteria.




Any observations made during routine monitoring, as well as during internal and external auditing will trigger maintenance tasks to ensure the CSG water storage in question continues to meets all required performance criteria. Australia Pacific LNG has also developed procedures to respond effectively to emergency situations associated with CSG water storages should they arise (see Section 8.5).

8.2.3 Use of untreated CSG water

By beneficially using CSG water (either untreated or treated), Australia Pacific LNG is helping to reduce pressure on existing regional water sources. In order to ensure that CSG water is used as efficiently as possible, and therefore to reduce the risk that reliance on existing water sources increases, Australia Pacific LNG develops procedures that guide all uses of CSG water. In addition to ensuring that the use of CSG water is conducted in manner that prevents adverse impact to EVs, these procedures also ensure that CSG water is not wasted.

As described, the use of untreated CSG water to support Australia Pacific LNG’s project activities will be implemented in accordance with the governing approvals dependent on the volume and quality of the CSG water stored, the volume and quality of the water required, and the location of the demand in relation to CSG water storages. The General BUA imparts obligations on the producer and user of the resource to ensure that the risks of impacting soil, surface water or groundwater EVs are appropriately managed. As well as complying with these obligations, Australia Pacific LNG also adopts measures outlined in the Detailed Construction Environmental Management Plan (Q-LNG01-15-MP-0144) and the Land Release Management Plan (CDN 11970260) and reproduced in Table 8-1. These include:

Prior to the commencement of water application, a range of environmental information relevant to the site in question is reviewed. This includes soils mapping and investigation, land use assessment, slope calculation, assessment of proximity to sensitive receptors, evaluation of site drainage and identification of ESAs;

The development of an up-to-date site plan clearly showing areas of water application and storage locations (where applicable). The site plan will be available on site at all times during water use;

CSG water quality data will be sampled and reviewed prior to application to confirm will not have a negative impact. Records will be retained for auditing purposes;

The application rate for CSG water will be set to avoid ponding or runoff from the application area. This will be determined by use of the project specific CSG Water Dust Suppression Calculator (Aecom, 2016); and

Application of CSG water will not occur during rainfall events.

Through the adoption and implementation of these controls, the risks associated with using CSG water to support project activities are ranked as ‘Low’ (See Table 8-1). No further treatment measures are therefore required however monitoring will be conducted to confirm that project water use continues in a manner that protects and maintains EVs.

Currently the use of untreated CSG water is undertaken by Australia Pacific LNG for Project Development due to its limited duration. The use of untreated CSG water for operations and maintenance is subject to further environmental review, ensuring its use meets the intent of the General BUA.

Table 8-1 indicates that all risks associated with operation of the untreated CSG water management scheme in the SGDA are controlled to ‘Low’ risk levels by the implementation of existing controls.




Table 8-1: Risks and Controls for the Untreated CSG Water Management Scheme

Risk Potential Cause Existing Controls Consequence Likelihood Risk Level

CSG Water Gathering Network

Uncontrolled release of CSG water adversely impacts soil, surface water and/or groundwater EVs.

Loss of pipeline integrity.

Release of CSG water from LPDs.

Gathering network designed in accordance with Australian Standards by suitably qualified engineers and in accordance with Gathering System Design Criteria, Philosophy and Procedure (Q-LNG01-10-AP-0012).

Integrity of gathering network managed through implementation of Integrity Management Plan: Polyethylene Pipelines (CDN 3675627) including:

o Right of way inspection prior to commencement of operation

o Ongoing right of way surveillance tailored to specific gathering network. Components may include; monitoring of third-party activities within corridor, monitoring for evidence of soil erosion and conducting leakage surveys.

Low point drains manually operated in accordance with Spring Gully EA and the LPD Water Quality Sampling – LNG (CDN 3675692) procedure.

Rehabilitation monitoring in accordance with the Spring Gully Rehabilitation Plan (CDN: 12883952) which includes monitoring of soil and vegetation indicators from loss of containment or LPD release impacts.

1

MINOR

2

HIGHLY UNLIKELY

LOW





CSG Water Storage

Seepage through liner and/or pond embankment adversely impacts soil, surface water and/or groundwater EVs

Failure of pond liner.

All regulated structures will be designed to contain the wetting front with an appropriate liner system in accordance with the Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2016).

Operation of the dam in accordance with the relevant dam’s Operations and Maintenance Manual (O&M manual) which includes:

o Sump monitoring involving water leak detection between the primary and secondary liners

o Controlling water quality

o Preventative Maintenance schedule, specifically pond repair process.

The Spring Gully Pond and Shallow Groundwater Monitoring Plan (CDN 3677458) is implemented to identify signs of seepage.

(Routine) LNG Dam Inspection Schedule (CDN 8333963) is implemented based on expert advice and undertaken by accredited inspectors.

RPEQ regulated dam inspections undertaken annually with recommended actions managed via a maintenance system.

2

MODERATE

2

HIGHLY UNLIKELY

LOW

Drowning of fauna and stock

Entry of fauna/stock into pond site.

New dams will be fenced. Fauna egress infrastructure is optional. 1

MINOR

3

UNLIKELY LOW





Failure of dam bund or overflow adversely impacts soil, surface water and/or groundwater EVs

Poor construction and / or operation.

Extreme rainfall causes volume stored to exceed capacity and / or to promote scour of embankments.

DSA/freeboard is available in each dam before the start of the wet season (1st November each year), verified by environmental audit.

Adequate freeboard in embankment design commensurate with the latest/current consequence category determined for the dam.

All new dams will be located above the 1:100 year annual exceedance probability (AEP) flood level.

Surface water diversion channels sized to convey runoff around pond embankments without causing additional erosion of land.

Embankments utilise homogeneous earth fill or zoned earth fills.

Routine dam monitoring program as outlined in the LNG Dam Inspection Schedule (CDN 8333963).

Operation of existing dam in accordance with the relevant dam’s Operations and Maintenance Manual (O&M manual) which includes:


o Operating water levels to TOWL (or where there is an integrated design system, operating water levels to ensure the combined Design Storage Allowance (DSA) is available)

o Preventative Maintenance schedule.

RPEQ inspections undertaken annually for regulated dams, with recommended actions managed via a maintenance system, including consequence assessments assessing dam break and failure to contain - overtopping.

Site water balance modelling undertaken quarterly.

3

SERIOUS

1

REMOTE LOW





Use of Untreated CSG Water

Ponding and/or runoff of CSG water adversely impacts soil, surface water and/or groundwater EVs

Poor practice during application of CSG water.

CSG water quality unsuitable for use.

All requirements for use outlined in the General BUA will be met.

Prior to the commencement of water application, a range of environmental information relevant to the site in question is reviewed and the CSG Water Dust Suppression Calculator (Aecom, 2016) is to be used to demonstrate no environmental impact by setting of an application rate (as addressed in the site plan).

Up-to-date site plan maintained clearly showing areas of water application and storage locations (where applicable).

CSG water quality data will be sampled and reviewed prior to application to confirm it will not have negative impacts for the duration of its use. Records will be kept for auditing purposes.

Application of CSG water will not occur during rainfall events.

Use of untreated CSG water for operations and maintenance activities will be undertaken in accordance with an environmental procedure.

1

MINOR

2

HIGHLY UNLIKELY

LOW

Vehicle incident/ accident leads to spill of CSG water and resultant adverse impact on surface water and/or groundwater EVs.

Driver error.

Poor road condition.

Poor weather.

Poor vehicle condition.

Land Transport Directive (ORG-HSE-DVE-001) and Fatigue Risk Management Directive (ORG-HSE-DVE-043) implemented.

All drivers to complete safe driver training.

All heavy vehicles fitted with In-Vehicle Monitoring System (IVMS).

Driver to inspect vehicle prior to use using the appropriate Safety Inspection Checklist.

Fatigue Risk Management Plan prepared, approved and implemented.

Vehicle Safety Checklists and required Journey Management Plans provided to site manager or business unit manager for record maintenance.

Driver to check with site during periods of wet weather to confirm roads are safe.

1

MINOR

3

UNLIKELY LOW




8.3 Treated CSG water management scheme

The future treated CSG water management scheme for the SGDA consists of beneficial use of treated CSG water for:

Project activities conducted in accordance with the General BUA;

Expansion Irrigation Scheme in accordance with the Irrigation General BUA; and

Injection into the Precipice Sandstone in accordance with the Spring Gully EA.

The Transition Stage CSG water management strategy continues to implement, for contingency to the beneficial use portfolio, release of treated CSG water to Eurombah Creek in accordance with the Spring Gully EA.

Table 8-2, presented at the end of this section, summarises all the risks as being ‘low’ based on the implemented existing controls associated with the current treated CSG water management scheme of the SGDA. The following sub-sections consider each component of this scheme in turn.

8.3.1 Project activities

By using treated CSG water as opposed to untreated CSG water, the consequence of potential impacts related to use of untreated CSG water quality are reduced.

8.3.2 Irrigation and livestock watering

Potential impacts to soil, surface water and groundwater EVs associated with irrigation schemes are well known and documented (see for example Biggs et al. 2012). Risks associated with irrigation include soil structure impacts, soil/water interactions (such as deep drainage) and those related to potential offsite water resource impacts (surface water runoff and soil erosion). Risks associated with livestock watering primarily relate to animal health and do not have the potential to impact surface water or groundwater EVs.

Irrigation systems have been design to prevent environmental impacts. An Irrigation Risk Assessment (in accordance with the framework established by ANZECC 2000) associated with the Expansion Irrigation Scheme has been undertaken to develop management practices, where required to: maintain soil structure, stability, and productive capacity; minimize potential toxic effects on crops; and maintain or improve yields of the irrigation area.

Australia Pacific LNG conducts the following monitoring.

Water quality monitoring at the supply point in accordance with the WQMP (refer to Appendix B).

Biennial soil sampling and monitoring within the existing Pongamia Plantation (in accordance with the procedure CDN 3677371) but which will be augmented to within the expanded irrigation area.

Biannual shallow groundwater monitoring, using the existing bore network for dam management in accordance with the plan CDN: 3677458. However the Expansion Irrigation Scheme proposal includes scope for additional observation piezometers (max 10m below ground level) within the augmentation area.

An soils and water assessment of impacts on the existing Pongamia plantation has been undertaken and concludes no adverse impacts on EVs to date (Origin, 2016).

No current livestock watering using treated CSG water is undertaken within the SGDA. However the risk assessment has included this potential option.

8.3.3 Aquifer injection

The Spring Gully aquifer injection scheme will be managed in accordance with the Spring Gully EA and the approved Spring Gully AIMP (CDN 11792487) designed to ensure the protection and maintenance of all relevant EVs.

The Spring Gully AIMP includes a comprehensive risk assessment, in conformance with the Australian Guidelines for Water Recycling: Managed Aquifer Recharge (NRMMC, 2009), of the potential environmental risks associated with the Spring Gully aquifer injection scheme.

An annual Spring Gully fluid injection is provided to the DEHP as part of the Annual Return.

8.3.4 River release

During the Transition Stage, contingent release of treated CSG to Eurombah Creek will be required when rates of treated CSG water use by the Pongamia Plantation are low due to seasonal climate or wet weather and/or during maintenance of the aquifer injection scheme. To monitor the potential impact of this release scheme on surface water EVs, Australia Pacific LNG implements regular and




ongoing monitoring in accordance with the Eurombah Creek REMP, approved by DEHP (refer to Appendix C). The program includes the monitoring of flow, aquatic habitat, bank stability, water quality, sediment quality, phytoplankton, zooplankton and aquatic macrophytes, and has been implemented since 2011. To date, the results of the Eurombah Creek REMP show no evidence to suggest that the release of treated CSG water has caused any adverse impact to surface water EVs. Therefore no assessment of potential impacts to Eurombah Creek from releases to surface waters releases is provided based on actual observations. The risk of discharge of treated CSG water is included in Table 8-2 for verification purposes.

The current REMP does not consider impacts on the WTST however does monitor macroinvertebrates which are a known food source for juvenile WTST (no discernible impacts to date). The existing REMP has been augmented with a dedicated turtle observation period (waterhole watches undertaken in general accordance with recommendations for visual survey of turtles as described in Eyre et al. (2014)) and concurrent search for nesting sites at existing monitoring sites whilst discharge continues to occur, taking effect in the 2017 spring survey.




Table 8-2: Risks and Controls for the Treated CSG Water Management Scheme


Use of Treated CSG Water for Irrigation

Contamination of water and soil and/or soil structure impacts impedes crop growth and yield.

Irrigation using water of an inappropriate quality.

CSG water treated to meet relevant water quality limits, supported by calcium dosing where required.

Online and fortnightly laboratory monitoring of treated CSG water quality to identify off-specification water.

Visual assessment of plant health for signs of wilting and discolouration.

Soil monitoring biennially.

2

MODERATE

2

HIGHLY UNLIKELY

LOW

Deep drainage promotes waterlogging and / or mobilisation of salts causing increased groundwater salinity.

Excessive irrigation application rate.

Ensure water applied at a sustainable rate such that soil structure and characteristics are maintained and deep drainage does not impact on groundwater quality or saturate the unsaturated zone.

Water balance modelling conducted to determine crop water use and in turn, to derive an irrigation budget that ensures application in accordance with crop requirements.

Treated CSG water to be applied using precision irrigation techniques to minimise surface water runoff.

All plant and equipment necessary to maintain compliance with the Irrigation General BUA will be installed, maintained and operated in proper and effective condition, and prevent soil compaction.

Reduce the risk of reportable uncontrolled releases of water from irrigation mainline, submain and reticulation to as low as reasonably practicable by ensuring operational monitoring / protection systems are of a high engineering integrity.

Biannual shallow groundwater monitoring to monitor rates of deep drainage.

1

MINOR

3

UNLIKELY LOW





Erosion causing increased turbidity and harming aquatic ecosystems.

Clearing for agriculture and / or excessive irrigation application rate.

Ensure water is applied at sustainable rate such that soil structure and characteristics are maintained and deep drainage does not impact on groundwater quality or saturate the unsaturated zone.

Water balance modelling conducted to determine crop water use and in turn, to derive an irrigation budget that ensures application in accordance with crop requirements.

Tractors and machines used on site will be light and will be restricted wherever possible to areas that are grassed.

Regular visual inspection of all natural drainage pathways. These inspections will identify:

o Signs of erosion or reduced vegetation;

o Evidence of siltation;

o Evidence of seepage; and/or

o Surface water ponding.

2

MODERATE

2

HIGHLY UNLIKELY

LOW

Use of Treated CSG Water for Livestock Watering

Use of treated CSG water for livestock watering causes animal harm.

Using water of an inappropriate quality.

Treat CSG water used for livestock watering to meet the relevant water quality limits.

Monitor treated CSG water quality to ensure water quality requirements are met.

Day-to-day stock welfare and management subject to agreement.

2

MODERATE

1

REMOTE LOW

Use of Treated CSG Water for Aquifer Injection

Inorganic chemicals, or metals (or pathogens) or salinity or sodicity in injectate degrade groundwater EVs.

Inorganic chemicals in injectate.

Injectate causing dissolution of metals from aquifer minerals.

Injection of treated CSG water reducing parameters of concern.

Deoxygenation at the PIP limits the potential for reactions in the aquifer.

Process control of aquifer injection scheme limits injectate water quality to 95th percentile of median formation water Total Dissolved Solids.

Off-specification water is automatically directed back to feed pond of WTF using inline analysers.

Ongoing monitoring of installed monitoring bores.

Refer to Spring Gully AIMP LOW

Turbidity and particulates degrade groundwater EVs.

Turbidity and particulates of injectate.

MF and RO at the WTF reduce turbidity and concentration of particulates. Refer to Spring Gully AIMP LOW





Rupture of the aquitard Over-

pressurisation of the injection well

Injection volumes and wellhead pressures will be recorded by online monitoring system and alarms setting of limits.

Mechanical design and integrity monitoring of bores. Refer to Spring Gully AIMP LOW

Impacts on groundwater –dependent ecosystems

Pressure impacts from injection.

Water quality of injectate.

Injected water will be of equal or better quality than in-situ groundwater.

Groundwater modelling used to confirm hydraulic and water quality risk to identified GDEs.

There are no precipice springs or potentially baseflow-connected watercourses in the vicinity of the injection site identified in the UWIR (QWC, 2012).


Impacts on existing entitlement holders

Pressure impacts from injection.

Water quality of injectate.

Injected water will be of equal or better quality than in-situ groundwater.

Groundwater modelling used to confirm hydraulic and water quality risk to landholder bores.


Use of Treated CSG Water for River Release

Change in geomorphology causing:

Increased gullying.

Notch erosion and increased risk of bank failure.

Entrainment of bed sediments, and redistribution downstream.

Increased flow.

Stream power of treated CSG water entering receiving watercourse.

Hydraulic analysis conducted to determine geomorphological character of receiving watercourse reaches.

Engineering controls are used to dissipate stream power and provide localised control of velocity, reducing scour and erosion at the release location.

Implementation of the Eurombah Creek REMP allows for continual improvement of the understanding of existing geomorphic variance and potential impacts from the release scheme.

If indicated as necessary by REMP results, review bank and in-stream stabilisation options.

2

MODERATE

1

REMOTE LOW





Localised erosion of banks at release location increasing concentration of sediment in flow and leading to subsequent deposition downstream.

Stream power of treated CSG water entering receiving watercourse.

Hydraulic analysis conducted to determine geomorphological character of receiving watercourse reaches.

Engineering controls are used to dissipate stream power and provide localised control of velocity, reducing scour and erosion at the release location.

The release location is regularly inspected for scour and erosion. Adjacent banks and downstream reaches are inspected during REMP surveys.

2

MODERATE

2

HIGHLY UNLIKELY

LOW

Impacts to aquatic ecology from change in flow regime

Change in flow regime.

Continue to implement the Eurombah Creek REMP and continue to optimise the monitoring methodologies where feasible.

2

MODERATE

2

HIGHLY UNLIKELY

LOW

Impacts to aquatic ecology from water quality

Water quality of treated CSG water differs to that of receiving watercourse.

Only treated CSG water that meets the water quality criteria required by the Spring Gully EA (Condition B6) will be released to Eurombah Creek. Treated CSG water to be released undergoes calcium dosing to ensure that the minimum calcium concentration is achieved.

Treated CSG water quality is monitored at multiple locations within the treatment process.

2

MODERATE

2

HIGHLY UNLIKELY

LOW




8.4 Brine and salt management scheme

The following sub sections consider each aspect of the brine and salt management scheme in turn, as sourced from data provided in the BIR (Q-LNG01-95-RP-1763).

The risks and controls associated with the operational infrastructure of the preferred brine and salt management scheme are summarised in Table 8-3.

A comprehensive risk assessment for the operation of the forecast future brine and salt management scheme infrastructure will be undertaken once detailed design is completed and to support the necessary regulatory approval applications.

It should be noted that much of the infrastructure associated with the brine and salt management scheme such as the brine aggregation pipelines, crystalliser and RWF, is forecast to be required in approximately 20 years from now.

8.4.1 Brine ponds

Brine ponds are the currently operational brine and salt management scheme infrastructure. All brine ponds have been designed, constructed and operated in accordance with the Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2016) or applicable regulation of the time of design.

Existing control measures are considered sufficient to ensure that all risks associated with pond operation are ranked as ‘Low’.

8.4.2 Brine aggregation pipelines

The brine aggregation pipelines are forecast to be required in approximately 20 years time. The risk to EVs from the operation of the brine aggregation pipelines reflects the potential for a loss of pipeline integrity to cause an uncontrolled release of brine to the environment. Control measures considered to mitigate this risk include:

Ensuring that the brine pipelines are designed in accordance with Australian Standards by suitably qualified engineers;

Developing and implementing an ‘Integrity Management Plan’ which is specific to the pipeline material and network characteristics. This would share similarities with the management plan for the gathering network: Integrity Management Plan: Polyethylene Pipelines (CDN 3675627) which includes right of way inspection prior to commencement of operation and ongoing right of way surveillance tailored to the specific gathering network which may include monitoring for evidence of soil erosion, for leaks and of third-party activities.

8.4.3 Brine crystalliser

The brine crystallisers are forecast to be required in approximately 20 years time. A comprehensive risk assessment for the operation of the encapsulation facility will be undertaken once detailed design is completed and to support the necessary regulatory approval applications.

8.4.4 Salt encapsulation facility

The salt encapsulation facility is forecast to be required in approximately 20 years time. It will be designed, constructed and operated to the relevant standards for a RWF to safely store the solid salts derived by the crystallisation of the brine. A comprehensive risk assessment for the operation of the encapsulation facility will be undertaken once detailed design is completed and to support the necessary regulatory approval applications.




Table 8-3: Risks and Controls for the Brine and Salt Management Scheme – Current Infrastructure


Brine Storage

Seepage through liner and/or pond embankment adversely impacts soil, surface water and/or groundwater EVs

Failure of pond liner.

All regulated ponds will be designed to contain the wetting front with an appropriate liner system in accordance with the Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2016).

Operation of the dam in accordance with the relevant dam’s O&M manual which includes:

o Sump monitoring involving water leak detection between the primary and secondary liners


o Preventative Maintenance schedule, specifically pond repair process.

The Spring Gully Pond and Shallow Groundwater Monitoring Plan (CDN 3677458) is implemented to identify signs of seepage.

(Routine) LNG Dam Inspection Schedule (CDN 8333963) is implemented based on expert advice and undertaken by accredited inspectors.

RPEQ regulated dam inspections undertaken annually with recommended actions managed via a maintenance system.

2

MODERATE

2

HIGHLY UNLIKELY

LOW





Failure of pond bund adversely impacts soil, surface water and/or groundwater EVs

Poor construction and / or operation.

Extreme rainfall causes volume stored to exceed capacity and / or promote scour of embankments.

Dams designed and constructed under the supervision of a suitably qualified and experienced person.

DSA/freeboard available in each pond before the start of the wet season (1st November each year, verified by a REPQ dam inspector) commensurate with the consequence category of the dam.

All ponds are located above the 1:100 year flood level.

Surface water diversion channels sized and installed to convey runoff around pond embankments without causing additional erosion of land.

Embankments are structurally designed and utilise homogeneous earth fill or zoned earth fills.

Operation of existing dam in accordance with the relevant dam’s O&M manual which includes:


o Operating water levels to TOWL (or where there is an integrated design system, operating water levels to ensure the combined DSA is available)

o Preventative Maintenance schedule.

(Routine) LNG Dam Inspection Schedule (8333963) is implemented.

RPEQ inspections undertaken annually for regulated dams, with recommended actions managed via a maintenance system, including consequence assessments assessing dam break and failure to contain - overtopping.

Site water balance modelling undertaken quarterly.

3

SERIOUS

1

REMOTE LOW

Secondary salinity (arising from wind-borne salt from brine ponds) adversely impacts terrestrial ecology, soils and/or surface water EVs

Wind-borne salt.

Pond design considers prevailing wind-direction and influence of fetch on potential wave height and run-up in design of freeboard allowance.

No forced agitation of pond surface.

Regular monitoring of surrounding vegetation will be undertaken as part of the monitoring of embankment condition to identify any preliminary signs of salinity effects during routine inspections.

2

MODERATE

2

HIGHLY UNLIKELY

LOW

Drowning of fauna and stock in brine ponds

Entry of fauna and stock into pond site.

Ponds will be fenced. Fauna egress infrastructure is optional. 1

MINOR

3

UNLIKELY LOW




8.5 Incident and emergency response

Australia Pacific LNG operates under an established Health, Safety and Environment Management System (HSEMS) to minimise and manage the impacts on employees, contractors, the environment and the communities in which the company operates (see Error! Reference source not found.).

The design process and subsequent day-to-day operation of all CSG water management assets incorporates a series of measures designed to ensure their continued and safe performance. In the event of an unexpected scenario occurring, incident or emergency responses are implemented in accordance with directives in which all relevant staff are trained.

Origin’s crisis and emergency response framework consists of a three tier structure consisting of Site Emergency Response, Group Emergency Management and Crisis Management.

The site-specific Emergency Response Plan (CDN 3677536) outlines specific emergency responses for the SGDA. The primary mechanism for potential for harm to the environment (relevant to CSG water management activities) is unmanaged large volume releases of CSG water, treated CSG water or brine (e.g. uncontrolled release from pond or pipeline rupture).

Figure 8-3: Crisis and Emergency Response Framework

All environmental incidents in the SGDA are responded to in accordance with the LNG Environmental Incident Procedure (CDN 3675694). All incident response processes are recorded and closed out through OCIS with incident reports stored for no less than the life of the project.

9. Management Criteria

In accordance with the EP Act, Australia Pacific LNG has developed measurable criteria (termed management criteria) against which the effectiveness of CSG water and brine management will be monitored.

Table 9-1 presents the management criteria for the Spring Gully CSG water management strategy. Each component of the water and brine management strategies has been assigned a specific management criterion and together, these criteria account for the quantity and quality of all water used, treated, stored or disposed of in the development area. Several management criteria also inherently address the management of waste (primarily brine) generated during the treatment of CSG water.

Each management criterion consists of:

A management objective for protecting EVs from the potential impacts of the CSG water management activity;

A series of tasks that will ensure that the objective can be achieved;




Specific indicators against which the performance of CSG water management can be measured, assessed and audited in an objective and repeatable manner; and

A target for CSG water management.

The continued suitability of all management criteria and operational performance against each criterion will be regularly evaluated and reported once a year in the Spring Gully EA annual return . During this process, if it is found that a management criterion has not been met, the following activities will be undertaken.

Investigate significance of failure to meet management criterion on EVs and identify likely cause/s.

Where cause/s can be attributed to the activities of Australia Pacific LNG, and where required in order to protect EVs, identify means to refine operating procedures in order to ensure that criterion is met in future.

Where required in order to protect and maintain EVs, implement any recommended changes to operating procedures.

Changes to the management criteria in Version 7 of this CWMP have been undertaken to clarify compliance in relation to the Transition Stage and future CSG water management strategy.




Table 9-1: Management Criteria of the Spring Gully CWMP (applicable to the Spring Gully and Injune EAs)

Objective Task Performance Indicator Performance Target

1 - No unauthorised disturbance of environmentally sensitive areas due to CSG water management activities.

Comply with disturbance allowances specified in EA.

Disturbance approvals secured through implementation of Disturbance Procedure (3675693, 3675803, 3675804, 3675805).

For all relevant activities, ensure that Environmental Constraints Assessment - Preparation and Issue (Q-LNG01-15-AW-0014) is followed.

Monitor the condition of Commonwealth- and QLD State-listed species and communities and endangered regional ecosystems in accordance with The Spring Gully Environmental Constraints Planning and Field Development Protocol (Q-8200-15-MP-1157).

Develop and implement an approved Cultural Heritage Management Plan.

Records of environmental constraints assessments and evaluation of compliance against Disturbance Procedure (3675693, 3675803, 3675804, 3675805).

Extent of unauthorised disturbance of ESAs.

Full compliance with Disturbance Procedure (3675693, 3675803, 3675804, 3675805) and Environmental Constraints Assessment - Preparation and Issue (Q-LNG01-15-AW-0014) demonstrated through records stored on Disturbance Tracker intranet site.

Zero unauthorised disturbance of ESAs.

2 - No unauthorised releases to the environment from the water gathering network.

Develop and implement an Operations and Maintenance Plan for the gathering network. Ensure this plan addresses the operation of valves, low point drains, high point vents and pipeline leak detection and isolation procedures.

Respond to all incidents in accordance with LNG Environmental Incident Procedure (CDN 3675694).

Volume of unauthorised leaks or spills from pipelines.

Records of incidents, investigations and close out processes.

Zero unauthorised leaks or spills from pipelines.

Zero OCIS incidents with overdue actions.





3 - No unauthorised releases to the environment from Regulated Structures.

Design, construct and operate all Regulated Structures in accordance with the requirements of the Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2016 or as updated).

Maintain register of Regulated Structures.

Develop and implement a Shallow Groundwater Monitoring Plan to identify potential seepage from ponds.

Implement inspection program as outlined in the Dam and Pond Inspection Guide (3675543).

Respond to all incidents in accordance with LNG Environmental Incident Procedure (3675694).

Implement the Spring Gully Development Area Rehabilitation Plan (12883952).

Develop and implement a brine and salt management plan to mitigate potential impacts of brine management including the potential for secondary salinity.

Volume of unauthorised releases from Regulated Structures.

Compliance with requirements of Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2016 or as updated).

Change in groundwater quality.

Records demonstrating compliance with implementation of Dam and Pond Inspection Guide (3675694).


Trends in data collected through rehabilitation monitoring.

Zero unauthorised releases from Regulated Structures.

Mandatory reporting level marked on all Regulated Structures and provide for DSA in all Regulated Structures by 1 November each year.

No exceedance of trigger value specified in Spring Gully Pond and Shallow Groundwater Monitoring Plan (CDN 3677458) attributable to management of Regulated Structures

Records of compliance with the Dam and Pond Inspection Guide (CDN 3675694) up to date.


Preparation and submission of the Plan of Operations for the SGDA including disturbance and rehabilitation activities.

4 - Take all reasonable steps to evaluate and, where appropriate implement, means to optimise CSG water and brine management.

Develop and maintain a numerical reservoir model to predict CSG water production over the life of the development area.

Continue to investigate opportunities to improve water and brine management and prioritise these options in accordance with the CSG Water Management Policy (DEHP 2012).

Develop and maintain a site water balance model to optimise the implementation, size and operation of water management infrastructure.

Evaluate feasibility of brine concentration technologies.

Evidence that performance of CSG water and brine management system is being continually assessed and that, where required, alternative means to optimise the systems are being investigated.

Progress towards delivery of study assessing beneficial uses of brine and salt.

Where appropriate for the development area, performance of CSG water and brine management system as demonstrated by site water balance model.

Site water balance model shows that existing and planned infrastructure remains effective at managing the forecast rate of CSG water and brine production.





5 - Maximise the beneficial use of CSG water.

Develop and maintain a numerical reservoir model to predict the quantity and quality of CSG water production over the life of the development area.

Prioritise water use in accordance with the CSG Water Management Policy (DEHP 2012).

Develop and implement operational and control philosophies for the WTF.

Develop and implement WQMP to ensure that water quality is fit for its beneficial use.

100% beneficial use of CSG water. Transition Stage:

Execute and implement the Expansion Irrigation Scheme

Upgrade the capacity and reliability of the aquifer injection scheme to achieve instantaneous capacity of 5 ML/d with 70% availability.

Future CSG water management strategy:

100% beneficial use of CSG water.

6 - Supply CSG water to beneficial uses in accordance with EA or BUA.

Ensure EA or BUA requirements for use in question are met.

Develop and implement WQMP to ensure that water quality is fit for its use.


Develop and implement site am Emergency Response Plan for the WTF.

Water supplied and used in accordance with relevant EA or BUA conditions.

Groundwater, surface water and soils monitoring programs developed in order to effectively monitor potential impacts from beneficial use options.

Change in surface water quality.

Change in groundwater quality.

Change in soil quality.


No non-compliance with EA or BUA conditions for beneficial uses.

For surface water monitoring, parameter concentrations maintained within WQOs identified in REMP.

For groundwater monitoring, parameter concentrations maintained within 10% of long term average background levels.

For soils monitoring, maintenance of soil structure, stability and productive capacity.


7 - Where beneficial uses are proven to be infeasible, ensure that treated CSG water disposal complies with Environmental Authority.

(Applies to Transition Stage only)

Ensure that any release of treated CSG water to surface water meets the requirements of the relevant EA.

Develop, secure approval of and implement REMP that meets the requirements of the EA.


Non-conformances against conditions related to disposal option in EA.

Implementation of approved REMP.

Change in surface water quality, aquatic habitat and/or species composition and abundance.

No non-conformance against conditions related to disposal option in EA.

Sampling events conducted as described in the approved REMP.

No discernible negative impact to surface water EVs attributable to treated CSG water release.




10. Monitoring

This section of the CWMP describes the monitoring undertaken to ensure the effective performance of CSG water management in the SGDA.

10.1 Overview

Monitoring undertaken in the SGDA consists of the following four (4) programs, as shown in Figure 10-1.

Monitoring aimed at ensuring operations are undertaken within an acceptable operating envelope;

Monitoring aimed at ensuring compliant CSG water and brine storage;

Monitoring aimed at ensuring compliance of CSG water use activities with the relevant governing approvals; and

Monitoring aimed at the prediction and early detection of any potential impact to EVs from CSG water management.

Data from the monitoring programs will be used to continually refine and improve the operation of the CSG water management scheme. A detailed description of each of the monitoring programs is provided in the following sub-sections.

Figure 10-1: SG CWMP Monitoring Programs




10.2 Operations Monitoring

Australia Pacific LNG implements a series of monitoring activities relevant to the daily operation of WTFs. Surveillance activities related to monitoring the system performance of the WTF are outlined in the Production Surveillance Plan (3675650). This document outlines monitoring activities, responsibilities and tools to determine if system performance is adequate. The required activities also include completing a root cause analysis assessing maintenance delays and identifying repeat events requiring attention and rectification in order to increase reliability.

All plant and equipment will be installed, maintained and operated in proper and effective condition.

10.2.1 Dam Monitoring

Australia Pacific LNG implements a range of inspection and monitoring procedures in order to ensure pond safety and to monitor the potential for environmental impacts. A summary of these procedures is provided in Table 10-1.

Table 10-1: Dam Monitoring Requirements

Activity Frequency Reporting Personnel Plan

Monitoring requirements

Shallow groundwater/ seepage

Water quality sampling – biannually

Any evidence of seepage raised as an incident in OCIS and reported in accordance with EA conditions.

Competent Environmental Advisors

Spring Gully Pond and Shallow Groundwater Monitoring Plan (CDN 3677458)

Regulated pond water quality monitoring

Annual DSA November 1 reports

Seepage monitoring reports

Competent Environmental Advisors

Suitably qualified staff/ laboratory accredited by National Association of Testing Authorities (NATA)

Embankments Requested by Technical Authority – Dams (Defect based)

EAMS Qualified surveyors

Asset Integrity Management Plan for Dams (CDN 3675617)

Inspection requirements

Compliance inspection

Annual Inspection report to be submitted to Queensland Government in accordance with relevant EA conditions.

Suitably Qualified and Experienced Person





Activity Frequency Reporting Personnel Plan

Embankments (cracking, erosion, seepage, subsidence and settlement, liner damage)

Spillways

Pond water level

Seepage

Sump pump test

As per the LNG Dam Inspection Schedule (CDN 8333963)

EAMS Authorised Dam Inspectors


Maintenance Requirements

Maintenance Schedule

Regulated Dam Routine Maintenance Schedule (CDN 8333974)

EAMS Technical – Civil Asset Integrity Management Plan for Dams (CDN 3675617)

Documentation Requirements

Regulated Dam Register

Maintained as current and accurate

EA Annual Return Senior Environmental Advisor - Water

Environment Sharepoint

10.2.2 CSG Quality Monitoring

The Spring Gully WQMP (CDN 8600569), refer to Appendix B, describes the monitoring and response procedures undertaken to ensure that CSG water produced in the SGDA is used in accordance with relevant governing approvals. It identifies the parameters to be monitored, the water quality limit levels that trigger management responses, and the responses and reporting procedures to be undertaken dependent on the beneficial use activity.

The Spring Gully WQMP applies to the compliance water quality monitoring requirements associated with the following activities in the SGDA:

Use of CSG water and/or treated CSG water for project activities;

Use of treated CSG water for irrigation;

Use of treated CSG water for stock watering and incidental land management;

Use of treated CSG water for aquifer injection;

Use of treated CSG water for landscaping and revegetation; and

Release of treated CSG water to surface waters.

The Spring Gully WQMP identifies the locations of monitoring points, the relevant approval document (the Spring Gully EA, the General BUA or the Irrigation General BUA) and the references available for sampling to ensure compliance with the Monitoring and Sampling Manual 2009 (DEHP 2013). Responsibilities for sampling are defined in the Production Operations Compliance Water Quality Monitoring Plan (CDN 3675645).

CSG water quality is monitored throughout the treatment process, including via on-line monitoring within the facilities supported by manual samples collected by WTF operators. The Spring Gully WTF sampling and analysis plan (CDN 3677461) outlines these activities for the SGDA WTF. The parameter values, set points, alert levels, quality control points and critical control points are set to ensure that the supply of treated CSG water complies with the quality requirements for the end use. Alarm levels also apply to aquifer injection and are described in the Spring Gully AIMP.




10.2.3 Environmental Monitoring

10.2.3.1 Surface Water Receiving Environment Monitoring Program

The Eurombah Creek REMP (CDN 8600568), refer to Appendix C, has been implemented since 2011. It includes monitoring of flow, aquatic habitat, bank stability, water quality, sediment quality, phytoplankton, zooplankton and aquatic macrophytes with the aim of identifying any potential impacts from the release of treated CSG water.

The results of the monitoring are summarised once a year in an annual report, and in quarterly interim reports.

10.2.4 Pond and Shallow Groundwater Monitoring Plan

Australia Pacific LNG’s shallow groundwater monitoring is comprised of two (2) components:

Monitoring of groundwater at bores surrounding a containment facility to identify any seepage from the containment facility; and

Monitoring of the water quality of the containment facility itself to determine how best to respond to uncontrolled releases.

Australia Pacific LNG undertakes shallow groundwater monitoring around ponds along with water quality monitoring of the water stored in ponds in order to:

Detect and report potential seepage from ponds to the subsurface;

Establish background groundwater quality to derive criteria for ongoing monitoring; and

Provide sufficient monitoring surveillance of groundwater conditions such that any seepage would be identified in an appropriate timeframe.

The Spring Gully Pond and Shallow Groundwater Monitoring Plan (CDN 3677458) describes the shallow groundwater monitoring program, including parameters to be monitored and monitoring frequencies. Should a trigger value be exceeded, the following phased investigation will be implemented:

Verification (validate the exceedance);

Evaluation (characterise extent and potential harm caused by seepage); and

Further assessment and/or corrective actions (e.g. stop source of leak, further monitoring, modification of activities or remediation).

The results of the monitoring and summarised after each monitoring round.

10.2.5 Deep Groundwater Monitoring Plan

The Spring Gully AIMP outlines the monitoring of groundwater pressure and water quality that will be conducted to assess potential hydraulic and water quality impacts within the Precipice Sandstone and Hutton Sandstone resulting from injection. The locations of monitoring bores have been selected based on the results of the aquifer injection trial, hydraulic and water quality impact zone monitoring, and the location of potential receptors.

Groundwater level data from the overlying aquifers will be reviewed to assess whether pressure effects have transmitted across the intervening Evergreen Formation aquitard, and to ensure preferential pathways have not developed in the grout sheath surrounding the casing of the injection bores or local monitoring bores.

Groundwater quality data will be assessed to understand whether injectate-groundwater and injectate-rock mass chemical reactions have occurred that may result in environmental harm or that may affect the long-term viability of the injection scheme.

Water quality samples will be collected from the in-field monitoring bores every six (6) months. Regional monitoring bores will be sampled annually. All water quality monitoring will include sampling for physicochemical parameters, major and minor ions and dissolved and total metals as outlined in the Groundwater Monitoring Plan (Q-LNG-01-10-MP-0005).

10.2.6 Soils Monitoring Program

Australia Pacific LNG implements land and soil management plans and monitoring programs wherever CSG water management activities have the potential to impact these EVs.

For all relevant work sites, the Contractor must prepare and adhere to a site-specific erosion and sediment control plan developed in accordance with best practice erosion and sediment control (IECA




2008). This includes a surface water monitoring program designed to detect impacts from sediment runoff into waters in accordance with the Construction Monitoring Program (Q-4500-15-MP-1002).

The Spring Gully WQMP (CDN 8600569) outlines requirement for monitoring of the water collected in LPDs. In accordance with the Spring Gully EA, where water quality and location criteria are met, CSG water from low point drains may be released to land. Prior to these activities commencing, site environmental assessment information is reviewed including soils mapping, results of any site soils investigations, land use, slope, proximity to sensitive receptors, site drainage and ESAs.

A soils monitoring program is also implemented at the Pongamia plantation as part of the Spring Gully Agriculture Resource Management Plan (CDN 11780805) in order to ensure that the irrigation operation does not adversely impact soils (Note: to be updated to include additional irrigation areas that are part of the future CSG water management strategy and the associated environmental monitoring). The procedure for biennial soil sampling (CDN 3677371) includes soil core sampling at a series of locations within the site and allows for analysis of soil samples by a NATA-accredited laboratory. This soil sampling supplements the monitoring of vegetation health, surface water and alluvial groundwater in the vicinity of the Pongamia Plantation to collectively ensure that the scheme has no detrimental impact on relevant EVs.

11. Management Systems and Records

As the appointed operator of the SGDA, Origin Energy’s key management systems, which represent the mechanism by which this CWMP will be implemented, are presented in this section of the CWMP. They include:

Health, safety and environment management system;

Project delivery process;

Complaints and customer satisfaction system.

Origin Energy’s Purpose, Principles, Values and Commitments are presented in the form of “Our Compass”6, an approach that provides clear and concise guidance for everyday decision making. The development of this CWMP and the implementation of the SGDA CSG water management strategy have, and will continue to be guided by the Our Compass approach.

11.1 HSEMS

Origin Energy operates under a health, safety and environment (HSE) policy and the HSEMS to minimise and manage the impacts on employees, contractors, the environment and the communities in which the company operates. The HSEMS has been developed with reference to Australian/New Zealand Standard ISO 14001 - Environmental Management Systems and AS 4801 - Occupational Health and Safety Management Systems.

The framework of the HSEMS is presented in Figure 11-1 and is implemented through a continuous improvement cycle of Commit Plan Do Check Review. Each element of the continuous improvement cycle is executed through a set of Company standards and directives, all of which support the HSE policy.

The HSEMS comprises two key HSE directives – HSE System and HSE Risk Controls. The revised HSE framework is provided in Figure 11-2.

6 Further information on “Our Compass” is located at http://www.originenergy.com.au/232/Our-Compass




Figure 11-1: Elements of the HSEMS and Continuous Improvement

Figure 11-2: HSE Framework




11.2 Operations Environmental Management Plan

An Operations Environmental Management Plan (OEMP) (CDN 3675641) applies to the SGDA, and underpins part of the Australia Pacific LNG Operations HSE Strategy (CDN 7471963).

The OEMP outlines how each of the HSE elements of the HSEMS directives are implemented. This OEMP provides an EMS Document Guide (CDN 15778124) that cross references all environmental controls.

11.3 Project Delivery Process

The Project Delivery Process (PDP) provides a structured and transparent project management process to support the following components:

Identification and assessment of alternative options;

Selection and development of the highest performing option/s;

Effective implementation and execution of the project; and

Reliable operation of all assets.

Whilst the PDP mandates the completion of specific activities, the means of achieving these requirements are flexible to site-specific factors. The PDP is therefore fit-for-purpose in all situations. The methodology is characterised by the following:

The process addresses the full lifecycle of the project;

Projects progress in a series of controlled phases with a formal decision review at the end of each phase;

Each phase include decision gates, primary activities and deliverables;

Projects only progress through a decision gate after detailed scrutiny of their risks, assurance having been provided that these risks can be effectively managed;

Controlled delivery is assured by having the need to meet defined objectives and targets agreed early with the project manager and key stakeholders;

Sufficient time is taken in the early phases of the project to assess and identify value drivers and risks before committing to major expenditure;

The organisational structure is set up to support the delivery of projects, including sufficient multi-functional resources through the lifecycle; and

Continuous improvement and performance measurement are built in to each phase.

The PDP requires that a Basis of Design be completed during the ‘Develop’ phase of the project. The Basis of Design outlines:

The scope of the facilities to be built;

Information on the process technology and process design standards; and

Definition of the functional requirements, physical parameters, regulatory requirements, codes and minimum discipline standards.

11.4 Complaints and Customer Satisfaction System

Origin Energy’s grievance and dispute resolution policy outlines the process for resolving a dispute, grievance or complaint from a stakeholder. Complaints received from external stakeholders will be investigated and communication with the complainant is normally undertaken within 24 hours. The results of the investigation will be communicated back to the complainant within a reasonable timeframe with a record of the complaints and any actions taken recorded in the complaints database.

The existing Origin Energy complaints database, consistent with Australian Standards ISO 10002:2006 - Customer Satisfaction – Guideline for complaints handling in organisations, will be used to record any complaints.




11.5 Environmental Data Management System

EsDAT, an environmental data management system, has been selected by Australia Pacific LNG as the internal database for the storage of all laboratory-derived water quality data. EsDAT allows for the management of data, supports trend analysis and provides a systematic approach to record keeping in order to ensure ongoing data integrity. All EsDAT records will be retained for no less than 5 years.

11.6 OpenText

Integrated Gas controlled documents are managed in accordance with the Document Control OpenText eDRMS Procedure (CDN 3741039).

11.7 Origin Collective Intelligence System

Factual and accurate accounts of all incidents that occur in an Origin Energy-controlled jurisdiction are recorded in OCIS. OCIS provides a common platform for reporting incidents, observations and risks and any relevant or stand-alone actions. The information this system captures is used to improve Origin Energy’s ability to manage risks across the business. Additionally, OCIS is instrumental in reporting and managing incidents and risks at all levels from teams, sites and Business Units up to the Board level.

11.7.1 Incidents

OCIS is used to track incident investigation, reporting requirements and preventative and/or corrective actions. As the investigation and associated actions are completed, the incident can be reviewed and closed out.

Incidents reports are stored in OCIS for the duration of no less than the life of the project/activity. Where the facts of an incident are required to be provided to a regulatory authority, any correspondence and a summary of the communication is stored in OCIS against the relevant incident.

11.8 Risk Registers

For each operational site, a register documenting reasonably expected environmental risks is maintained. Each risk register is reviewed annually and updated to reflect any changes in the site operating philosophy.

The expected consequence, likelihood and exposure to each risk are documented in the risk register along with existing controls and any further actions required. Once the register has been populated, acceptance by a corresponding ‘Risk Acceptance Authority’ is required for the activity/operation to proceed (note that activities/operations can be accepted subject to an agreed treatment plan).

Populated risk registers are uploaded into Stature, along with any actions, for tracking. Completion of actions under an agreed treatment plan will prompt a review of the risk register to reflect the current situation.

11.9 Learning Management System

The training requirements of individual personnel are identified within a competency matrix. Origin Energy has a robust competence program delivered via ’People Connect’. Personnel are deemed to be a ‘competent person’ after completing the required combination of theoretical and practical training, education and experience modules, and after having been successfully assessed by competence assessors. A training and competency register shall be maintained for the life of the development areas. Training records and staff qualifications are stored and maintained in People Connect.

11.10 Enterprise Asset Management System

Origin Energy has developed a register to capture all Queensland CSG operational assets. The asset register includes details of existing infrastructure, including the regulated dams. This data is stored in the Enterprise Asset Management System (EAMS) and used to schedule routine tasks against particular assets (eg. inspections and pond monitoring). It also tracks actions in respect to scheduled and reactive maintenance on each asset.

11.11 ATLAS

ATLAS is an integrated environmental, social and regulatory compliance recording and reporting system that provides Australia Pacific LNG with the capacity to:

Record regulatory compliance conditions and environmental and social commitments;

Record required actions with due dates;




Assign tasks to users with due dates;

Link dependent conditions and actions;

Manage tasks; and

Record evidence of compliance.

Origin Energy uses ATLAS to record and track all regulatory requirements.

12. Reporting

This section of the CWMP describes the processes for routine and non-routine reporting applicable to CSG water management in the SGDA.

12.1 Routine

12.1.1 Monitoring Results

All water quality monitoring laboratory results are available through EsDAT. ESdat also has the capability to notify relevant users via email if results exceed trigger levels such as EA water quality specifications.

Daily operator monitoring results are recorded in a separate database (the MPM database), as are continuous online SCADA data records (the Historian database). An over-arching centralised integrated operations system provides a portal to access, analyse and receive alerts from the MPM and Historian databases.

An annual report of all monitoring undertaken in support of the CWMP and the Spring Gully EA is provided to the DEHP in accordance with appropriate legislative and regulatory approval requirements.

12.1.2 Audits and Reviews

The CWMP is subject to periodic reviews and updates in accordance with the EA.

Review and update of this CWMP will be undertaken throughout the continuous improvement cycle and may be triggered by:

Any appropriate and relevant recommendations from the annual CSG water management evaluation reports;

Unsuitable/unsustainable (non-representative) management criteria;

Any significant change (>10%) to the long term estimated CSG water or brine production profiles, or change in the peak production period;

Any significant change to CSG water quality, treated CSG water quality or brine quality;

Implementation of a new management strategy not already addressed by the CWMP;

Any appropriate and relevant recommendations resulting from an incident investigation;

Any appropriate and relevant recommendation resulting from review of monitoring program results/data;

A request by the regulator; or

Any significant change to relevant legislation and/or government policy (eg. BUA framework).

12.1.3 Compliance

Annual returns will be submitted to DEHP showing how the conditions of the Spring Gully EA have been met for the preceding year. The annual return will also assess the effectiveness of CSG water management against the management criteria outlined in Section 9 via a CSG Water Management Evaluation Report.

12.2 Non-routine

12.2.1 Monitoring Results

Monitoring results will be reviewed regularly and non-compliance of conditions in the Spring Gully EA will be reported within the relevant timeframe to the appropriate authority. Australia Pacific LNG will internally report non-compliances or exceedances to management as soon as possible upon receipt of the results/becoming aware and in accordance with the LNG Environmental Incident Procedure (CDN 3675694).




12.2.2 Incident and Emergency Events

All incidents will be managed in accordance with the LNG Environmental Incident Procedure (CDN 3675694), which includes internal and external reporting and record keeping requirements.

The Spring Gully Operations Emergency Response Plan (3677536) defines the actions required to effectively respond to a crisis and/or emergency situation.

13. References

AECOM, 2016. Australia Pacific LNG CSG Water Dust Suppression Calculator, Version 2.1. AECOM, Fortitude Valley.

Australian Government, 1999. Environment Protection Biodiversity Conservation Act 1999.

Australian and New Zealand Environment and Conservation Council & Agriculture and Resource Management Council of Australia and New Zealand, 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality, ANZECC and ARMCANZ, Australia.

Australia Pacific LNG, 2010. Australia Pacific LNG Project Environmental Impact Statement, Australia Pacific LNG, Australia

National Health and Medical Research Council, 2011. Australian Drinking Water Guidelines Paper 6. National Water Quality Management Strategy, NHMRC, Canberra.

Biggs, A.J.W., Witheyman, S.L., Williams, K.M., Cupples, N., de Voil, C.A., Power, R.E. and Stone, B.J. 2012. Assessing the salinity impacts of coal seam gas water on landscapes and surface streams. Final report of Activity 3 of the Healthy Headwaters Coal Seam Gas Water Feasibility Study, DNRM, Brisbane.

Boobook Ecological Consulting, 2017. Fauna Survey Report – Survey for White-throated Snapping Turtle (Elseya albagula) at Eurombah Creek, Spring Gully Gas Field. Boobook, Roma.

frc environmental, 2013. Aquatic Ecology Assessment: Spring Gully Development Area, frc environmental, Brisbane.

GHD, 2013, Spring Gully Terrestrial Ecology Assessment Australia Pacific NG Upstream Phase 1 Q-8200-15-TR-1020, GHD, Brisbane.

Golder Associates, 2013, Spring Gully Development Area Topography, Geomorphology and Soils Assessment Q-8200-15-TR-1021, Golder Associates, Brisbane.

International Erosion Control Association, 2008. Best Practice Erosion and Sediment Control Guidelines, IECA, Australia.

Joo M., Yu B., Carroll C. and Fentie B. 2005. ‘Estimating and modelling suspended sediment loads using rating curves in the Fitzroy river catchment, Australia’, in (eds) Zerger, A. and Argent, R.M. MODSIM 2005 International Congress on Modelling and Simulation. Modelling and Simulation Society of Australia and New Zealand, December 2005.

National Resource Management Ministerial Council, 2009. Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (Phase 2) Managed Aquifer Recharge, NRMMC, Australia.

NRA Environmental Consultants, 2017. ‘EPBC Act Self-Assessment Report for the Spring Gully Water Treatment Facility Receiving Environent Assessment of Potential Impacts’. NRA Environmental Consultants, Townsville.

National Water Commission, 2012. Atlas of Groundwater Dependent Ecosystems, National Water Commission, Australia.

OGIA, 2015a. Wetland Conceptualisation; Sub-report 4, Scott’s Creek, Version 1.3, 20/05/2015, Department of Natural Resources and Mines, Brisbane.

OGIA, 2015b. Wetland Conceptualisation; Sub-report 1, Lucky Last and Abyss Complexes, Version 1.2, 20/05/2015, Department of Natural Resources and Mines, Brisbane.

OGIA, 2015c. Wetland Conceptualisation; Sub-report 11, Spring Rock Creek, Version 1.2, 20/05/2015, Department of Natural Resources and Mines, Brisbane.

Queensland Government Department of Environment and Heritage Protection, 2016. Manual for Assessing Consequence Categories and Hydraulic Performance of Structures, DEHP, Brisbane.

Queensland Government Department of Environment and Heritage Protection, 2014a. General Beneficial Use Approval Associated Water (including coal seam gas water), DEHP, Brisbane.




Queensland Government Department of Environment and Heritage Protection, 2014b. General Beneficial Use Approval Irrigation of Associated Water (including coal seam gas water), DEHP, Brisbane.

Queensland Government Department of Environment and Heritage Protection, 2013. Environmental Protection Act 1994 Guideline: Application requirements for petroleum activities, DEHP, Brisbane.

Queensland Government Department of Environment and Heritage Protection, 2013b. Monitoring and Sampling Manual 2009, DEHP, Brisbane.

Queensland Government Department of Environment and Heritage Protection, 2012. CSG Water Management Policy, DEHP, Brisbane.

Queensland Government Department of Environment and Heritage Protection, 2011. Environmental Protection (Water) Policy 2009: Dawson River Sub-basin Environmental Values and Water Quality Objectives, DEHP, Brisbane.

Queensland Government Department of Environment and Heritage Protection, 2009. Queensland Water Quality Guidelines, DEHP, Brisbane.

Queensland Government Department of Natural Resources and Mines, 2013. Fitzroy Basin Resource Operations Plan, DNRM, Brisbane.

Queensland Government Department of Natural Resources and Mines, 2012. Great Artesian Basin Resource Operations Plan, DNRM, Brisbane.

Queensland Government Department of Natural Resources and Mines, 2006. Water Resource (Great Artesian Basin) Plan, DNRM, Brisbane.

Queensland Water Commission, 2012. Underground Water Impact Report for the Surat Cumulative Management Area, Queensland Water Commission, Brisbane.

RPS, 2011. Spring Gully Discharge to Surface Watercourse Modelling, RPS, Australia.

Scott, Paul T. Pregelj, L. Chen, N. Hadler, J. S. Djordjevic, M. A. and Gresshoff, P. M., 2008 ‘Pongamia pinnata : An Untapped Resource for the Biofuels Industry of the Future’, Bioenergy Research, vol. 1, pp. 2-11.




14. Document information and history

DOCUMENT CUSTODIAN GROUP

Title Name/s

IG-Operations-APLNG-HSE Stuart Fletcher

DOCUMENT HISTORY

Rev Date Changes made in document Reviewer/s Consolidator

Approver

0 29/06/2011 Issued to DERM SM DC

1 21/10/2011 Issued to DERM in response to RFI

VC JM

2 16/01/2012 Issued for Approval TA JM

3 22/03/2013 Issued for use K. Presley J. Mitchell D. Carberry

4 09/01/2015 Draft issue as proposed CWMP for DEHP pre-lodgement

A. Lane K. Presley J. Mitchell

5 27/11/2015 Brine Management Plan updated; Profiles updated

T. Hill J. Murray V. Cavanough

6 08/02/2017 Issued for EPBC Referral V. Cavanough J. Long M. Renfree

S. Fletcher

7 22/11/17 Issued in response to IESC advice for SGDA NW/NE EPBC Referral – various updates

J. Long S. Dale A. Skelly M. Renfree R. Morris S. Rutledge

V. Cavanough S. Fletcher




Appendix A Origin Energy Document References

Document Number Title (historical document number)

CSG Water Production and Strategy

Q-LNG01-95-RP-1763 Australia Pacific LNG Project Brine Investigation Report

3675645 Production Operations Compliance Water Quality Monitoring Plan

8600569 CSG Water Quality Monitoring Program: Spring Gully Development Area (Q-8200-15-MP-0003)

3677461 Collect samples and complete routine analysis – Water Treatment Facility

Regulated Dams / Ponds

3675617 LNG Integrity Management Plan: Dams (OEUP-Q1000-PLN-ENG-002)

8333963 Regulated Dam Inspection Schedule

3677458 Spring Gully Pond and Shallow Groundwater Monitoring Plan (OEUP-Q8220-PLN-ENV-001)

Aquifer Injection

Q-8200-95-MP-1008 Spring Gully Aquifer Injection Management Plan

Q-8200-95-TR-0015 Spring Gully Aquifer Injection – Technical Feasibility Assessment

Pongamia, Irrigation

11780805 Spring Gully Agriculture Resource Management Plan (Q-8200-15-MP-1086)

11480941 Spring Gully Pongamia Monitoring Report 2014-2016

Surface Water Release

3677519 Monitor the upstream and downstream temperature at the treated permeate release point, Eurombah Creek

8600568 Spring Gully Receiving Environment Monitoring Program: Eurombah Creek

12556458 Spring Gully Receiving Environment Monitoring Program Annual Report 2015

13947082 Spring Gully Receiving Environment Monitoring Program Annual Report 2016

Other CSG Water Related

3675692 Low Point Drain Water Quality Sampling - LNG

Land Environment, Uses, Rehabilitation

12883952 Spring Gully Development Area Rehabilitation Plan (Q-8200-15-MP-0010)

11970260 Land Release Management Plan (Q-LNG01-15-MP-0354)

Q-8200-15-MP-1157 Spring Gully Environmental Constraints Planning and Field Development Protocol

3675693

3675803

3675804

3675805

Disturbance Procedure Gate 1: Scope (OEUP-Q1000-PRO-ENV-005) Gate 2: Ready to Scout (OEUP-Q1000-PRO-ENV-020) Gate 3: Final Layout Lockdown (OEUP-Q1000-PRO-ENV-021) Gate 4: Issue Disturbance Approval (OEUP-Q1000-PRO-ENV-022)

Q-LNG01-15-MP-0144 Detailed Construction Environmental Management Plan

Q-4500-15-MP-1002 Australia Pacific LNG Monitoring Program for Construction Activities

Incidents, Emergency, Reporting

3675694 LNG Environmental Incident Procedure: Production Operations Guideline & Toolkit (OEUP-Q1000-PRO-ENV-006)

3677536 Emergency Response Plan: Spring Gully Area Operations




Document Number Title (historical document number)

Gathering Infrastructure Design, Operation, Integrity

Q-LNG01-10-AP-0012 Gathering System Design Criteria, Philosophy and Procedure

3675627 Integrity Management Plan: Polyethylene Pipelines (OEUP-Q1000-PLN-ENG-016)

Corporate

ORG-HSE-DVE-100 HSE Risk Controls Directive

ORG-HSE-DVE-102 HSE System Directive




Appendix B Spring Gully CSG Water Quality Monitoring Plan (CDN 8600569)

PlanQLD 8200 ENV PLN

CDN/ID 8600569

THE THREEWHATS

What can go wrong?What could cause it to go wrong?What can I do to prevent it?


Review frequency: 03 years

For internal Origin use and distribution only.Subject to employee confidentiality obligations.


Integrated Gas

COAL SEAM GAS WATER QUALITY MONITORING PROGRAMSpring Gully Development AreaThis document describes the water quality monitoring undertaken in the Spring Gully development area to assess compliance against Queensland Government approvals for the use of coal seam gas water. It identifies monitoring locations, parameters to be sampled, water quality limit levels and exceedance response procedures.

Legacy Document Number: Q-8200-15-MP-0003

Review record

Rev Date Reason for issue Reviewer/s Consolidator Approver

0 29/06/2011 Issued to DERM JRM DC SM

1 28/04/2014 Issued For Use A Lane K Presley M Renfree

2 03/03/2015 Issued For Use A Lane K Presley M Renfree

2A 07/09/2016 Issued For Review VC VC -

3 10/10/2016 Issued For Use - - S Fletcher

3A 02/06/2017 Issued for review V Cavanough V Cavanough

4 07/09/2017 Issued for use - - S Fletcher

Spring Gully CSG Water Quality Monitoring Program CDN/ID 8600569

Released on 07/09/2017 - Revision 4 - Status Issued for useDocument Custodian is IG-Operations-APLNG-HSE

Origin Energy Upstream Operator Pty Ltd ABN 67 105 423 532 Page 2 of 17Once printed, this is an uncontrolled document unless issuedand stamped Controlled Copy or issued under a transmittal.Based on template: AUS 1000 IMT TMP 4881989_Revision 4_Issued for use_01/06/2017_IG-SystemsInfo-DocRecordsMgt

Table of contents

1. Introduction 3

1.1 Objective 3

1.2 Scope 4

1.3 Exclusions 4

2. Background 4

3. Terms, Abbreviations and Definitions 5

4. Document References 6

5. Scheme Description 6

5.1 CSG Water 6

5.2 CSG Water Use 7

5.2.1 Project Activities 75.2.2 Irrigation 85.2.3 Stock Watering and Incidental Land Management 85.2.4 Aquifer Injection 85.2.5 Release to Land 95.2.6 Release to Surface Waters 9

6. CSG Water Quality Monitoring 9

6.1 Overview 9

7. Water Quality Parameters and Limit Levels 11

7.1 Assumptions and Limitations 11

7.1.1 Irrigation 117.1.2 Stock Watering and Incidental Land Management 117.1.3 Project Activities - Landscaping and Revegetation 11

8. Sample Analysis and Data Management 16

9. Reporting and Incident Response 16


Table of figures

Figure 1: Document Interfaces 3

Figure 2: the Spring Gully CSG Water Treatment Process Flow Diagram 7

Figure 3: Spring Gully CSG Water Quality Monitoring Points (Points of Supply) 10

List of tables

Table 1: Approvals Governing the Use of CSG Water in the Spring Gully Development Area 4

Table 2: Spring Gully CSG Water Quality Monitoring Program Components 9

Table 3: Spring Gully Water Quality Monitoring Parameters 12




1. Introduction

1.1 Objective

This Coal Seam Gas Water Quality Monitoring Program (CSGWQMP) describes the monitoring and response procedures undertaken to ensure that coal seam gas (CSG) water produced in the Spring Gully development area is used in accordance with relevant regulatory approvals. It identifies the parameters to be monitored, the water quality limit levels that trigger management responses, and the responses and reporting procedures to be undertaken in each case.

This CSGWQMP will be implemented alongside the Production Operations Compliance Water Quality Monitoring Plan (3675645) which identifies all water quality monitoring commitments, both external and internal, for Australia Pacific LNG production operations.

This CSGWQMP is owned by the APLNG Operations HSE and will be updated at regular intervals as approvals change and as new uses of CSG water are authorised. Its relationship with key operational documentation is presented in Figure 1.

Figure 1: Document Interfaces




1.2 Scope

This CSGWQMP applies to the compliance water quality monitoring requirements associated with the following activities in the Spring Gully development area:

Use of CSG water and/or treated CSG water for construction activities (such as drilling, well completions and work-overs, hydraulic fracturing, earthworks and dust suppression)

Use of treated CSG water for irrigation

Use of treated CSG water for stock watering and incidental land management

Use of treated CSG water for aquifer injection

Use of treated CSG water for landscaping and revegetation

Release of untreated CSG water to land and

Release of treated CSG water to surface waters.

1.3 Exclusions

The following monitoring activities are outside the scope of this CSGWQMP:

Monitoring requirements not related to water quality (for example soil sampling)

Monitoring requirements for sewage treatment plants

Operational water quality monitoring at the Spring Gully water treatment facility (WTF) and Spring Gully permeate treatment facility (PTF)

Supply of treated CSG water for potable use

Inspection and water quality monitoring of regulated structures and non-regulated structures, and associated shallow groundwater monitoring and

Receiving environment monitoring.

2. Background

Petroleum activities in the Spring Gully development area are authorised by environmental authority EPPG00885313 (the Spring Gully EA), issued by the Queensland Government Department of Environment and Heritage Protection (DEHP). The Spring Gully CSG Water Management Plan (Q-8200-15-MP-001) (the Spring Gully CWMP) provides a complete description of the strategy for managing CSG water in the development area.

Uses of CSG water in the Spring Gully development area are currently authorised by one of two (2) approval types, as listed in

The Spring Gully EA or

Beneficial use approvals, issued by DEHP.

In addition, under the Environmental Protection Act 1994 (Qld) (the EP Act), Australia Pacific LNG has a general environmental duty to take all reasonable and practicable measures necessary to prevent or minimise environmental harm.

Table 1: Approvals Governing the Use of CSG Water in the Spring Gully Development Area


Use of CSG water and/or treated CSG water for construction activities, dust suppression, and landscaping and revegetation

General Beneficial Use Approval – Associated Water (including coal seam gas water) (DEHP 2014) (General BUA)

Use of treated CSG water for irrigationGeneral Beneficial Use Approval – Irrigation of Associated Water (including coal seam gas water) (DEHP 2014)(General BUA – Irrigation)

Use of treated CSG water for stock watering and incidental land management

General BUA





Use of treated CSG water for aquifer injection

Spring Gully EA (cross references the Aquifer Injection Management Plan (Q-8200-95-MP-1008))

Release of untreated CSG water to land Spring Gully EA

Release of treated CSG water to surface water

Spring Gully EA

3. Terms, Abbreviations and Definitions


ANZECC GuidelineAustralian and New Zealand Guidelines for Fresh and Marine Water Quality(ANZECC and ARMCANZ 2000)

BUA Beneficial use approval

CSG Coal seam gas

CSG waterWater produced from a CSG well to enable gas production. Also called associated water or produced water.

CSGWQMP Coal seam gas water quality monitoring program

CWMP Coal seam gas water management plan

DEHPQueensland Government Department of Environment and Heritage Protection

EA Environmental authority

EC Electrical conductivity

EP Act Environmental Protection Act 1994 (Qld)

General BUAGeneral Beneficial Use Approval – Associated Water (including coal seam gas water) (DEHP 2014)

Irrigation General BUAGeneral Beneficial Use Approval – Irrigation of Associated Water (including coal seam gas water) (DEHP 2014)

LPD Low Point Drain

OCIS Origin Collective Intelligence System

Point of Supply Location of monitoring point for monitoring covered by this CSGWQMP

POCWQMP Production Operations Compliance Water Quality Monitoring Plan

PTF Permeate treatment facility

SOP Standard operating procedure

TDS Total Dissolved Solids

Treated CSG waterWater produced from a CSG well which has undergone treatment prior to end use.

Untreated CSG waterWater produced from a CSG well which has not undergone treatment prior to end use.

WTF Water Treatment Facility




4. Document References

Reference Document

Q-8200-15-MP-0001 Spring Gully Coal Seam Gas Water Management Plan

3675641 Production Operations Environmental Management Plan

3675645 Production Operations Compliance Water Quality Monitoring Plan

Q-8200-15-MP-1086 Spring Gully Agriculture Resource Management Plan

Q-8200-15-MP-0002 Spring Gully Receiving Environment Monitoring Program: Eurombah Creek

3677458 Spring Gully Pond and Shallow Groundwater Monitoring Plan

Q-8200-95-MP-1008 Spring Gully Aquifer Injection Management Plan

3677461 Collect samples and complete routine analysis – Water Treatment Facility Spring Gully

3677519 Monitor the upstream and downstream temperature at the treated permeate release point, Eurombah Creek

3677371 Pongamia Plantation: Procedure for Annual Soil Sampling Monitoring Program

3675692 Low Point Drain Water Quality Sampling - LNG

Q-LNG01-15-MP-0354 Land Release Management Plan

3677469 Manage multiple discharge locations – Water Treatment Facility Spring Gully

3676266 Report a Non-Compliance

3675694 LNG Environmental Incident Procedure

5. Scheme Description

5.1 CSG Water

CSG water produced in the Spring Gully development area is gathered to the Spring Gully WTF where it is treated by disc filtration, membrane filtration, reverse osmosis and chemical dosing. Typically, a minority of the treated CSG water is used for project activities (such as construction activities, dust suppression and landscaping and revegetation), agricultural activities and release to surface waters. The majority of the treated CSG water undergoes further treatment at the Spring Gully PTF before being used for aquifer injection. The treatment processes at the Spring Gully PTF comprise ultra-violet disinfection, cartridge filtration and membrane degasification. A process flow diagram of the complete treatment system is shown in Figure 2.

Within the Spring Gully WTF and Spring Gully PTF, several water quality parameters are monitored continuously via inline sensors. No specific water quality limit levels from regulatory approvals apply to this monitoring however alarm levels are used by Australia Pacific LNG to warn operators of conditions outside the range of normal operations. Alarm levels also apply to aquifer injection and are described in the Spring Gully Aquifer Injection Management Plan (Q-8200-95-MP-1008).

Exceedances of alarm levels are managed in accordance with standard operating procedures (SOPs) and critical operating procedures.




Figure 2: the Spring Gully CSG Water Treatment Process Flow Diagram

5.2 CSG Water Use

The following subsections describe the uses of CSG water in the Spring Gully development area. Further assumptions and limitations are listed in Section 7.1.

5.2.1 Project Activities

Wherever practicable, water demands from Australia Pacific LNG project activities will be met by using CSG water or treated CSG water in accordance with the General BUA. Project activities include:

Construction activities (such as drilling, well completions and work-overs, hydraulic fracturing, facilities construction, hydro-testing of gathering networks)

Maintenance activities (such as road grading)

Dust suppression and

Landscaping and rehabilitation.

The General BUA imparts different requirements on each of these project activities, as described in the following subsections.

5.2.1.1 Construction Activities

The General BUA does not impart conditions on the producer of the CSG water related to the quality of any CSG water to be used for construction activities. However water quality monitoring associated with operation of the Spring Gully WTF, or the broader development area, may still be required.

The General BUA does impart the following requirements on the user of the CSG water for construction.

The use of the resource must not result in runoff from the construction site.

The use of the resource must not harm vegetation surrounding the construction site.

If there is an indication that one of the above impacts is occurring, the use must cease immediately, the administering authority must be notified within 48 hours, and the affected area must be remediated without delay.

5.2.1.2 Dust Suppression

The General BUA does not impart conditions on the producer of the CSG water related to the quality of any CSG water to be used for dust suppression. However water quality monitoring associated with operation of the Spring Gully WTF, or the broader development area, may still be required.

The General BUA does impart the following requirements on the user of the CSG water for dust suppression.




The amount of dust suppressant applied should not exceed what is required to effectively suppress dust.

The application of dust suppressant must:

not cause on-site ponding or runoff

be directly to the area being dust suppressed

not harm vegetation surrounding the area being dust suppressed and

not cause visible salting.

5.2.1.3 Landscaping and Revegetation

The General BUA imparts conditions on the producer of the CSG water related to the quality of any CSG water used for landscaping and revegetation. Compliance against the water quality limit levels is demonstrated by monitoring at the Permeate Tank Point of Supply, see Figure 3.

The General BUA also imparts the following requirements on the User of the CSG water for landscaping and revegetation.

The amount of CSG water applied should not exceed what is required to effectively undertake landscaping and revegetation activities.

The application of CSG water must:

Not cause on-site ponding or runoff

be directly to the area being landscaped or revegetated

not harm vegetation surrounding the area being landscaped or revegetated and

not cause visible salting.

If there is an indication that one of these impacts is occurring, the use must cease immediately, the administering authority must be notified within 48 hours, and the affected area must be remediated without delay.

5.2.2 Irrigation

In 2010, the Pongamia Plantation was commissioned as an agricultural beneficial use scheme for treated CSG water. Located 2.5 km northeast of the Spring Gully WTF, the plantation uses treated CSG water from the Spring Gully WTF to irrigate 300 ha of Pongamia pinnata. Irrigation at the Pongamia Plantation is conducted in accordance with the Irrigation General BUA.

Compliance against the water quality limit levels imparted on the producer of the CSG water and specified in the Irrigation General BUA is demonstrated by monitoring at the pump station of the Pongamia Plantation (the Agriculture Point of Supply), see Figure 3.

Information is provided in the Spring Gully Agriculture Resource Management Plan (Q-8200-15-MP-1086).

5.2.3 Stock Watering and Incidental Land Management

Australia Pacific LNG does not currently supply treated CSG water for stock watering and incidental land management. Available stock watering and incidental land management infrastructure is currently fed by the Precipice bore.

Australia Pacific LNG may supply treated CSG water for stock watering and incidental land management (eg. vehicle washdown and fire prevention) in the future in accordance with the General BUA. Compliance against relevant water quality limit levels will be monitored at the Agriculture Point ofSupply, see Figure 3.

5.2.4 Aquifer Injection

The Spring Gully Aquifer Injection Scheme will inject treated CSG water into the Precipice Sandstone aquifer at a maximum rate of 8.1 ML/d. The injection scheme is operated in accordance with the Spring Gully EA and as described in the Spring Gully Aquifer Injection Management Plan (Q-8200-95-MP-1008).

Water quality limit levels for water to be injected are specified in the Spring Gully EA and these parameters are sampled at the outlet of the Spring Gully PTF; the Aquifer Injection Point of Supply, see Figure 3.




5.2.5 Release to Land

Australia Pacific LNG is authorised by the Spring Gully EA to release untreated CSG water to land from Low Point Drains (LPDs) and for hydrostatic pressure testing.

A procedure for LPD water quality sampling has been prepared (3675692). Release limits are specified in the Spring Gully EA however the sample design requires random samples and quarterly sampling (both field and laboratory parameters).

For hydrostatic test water, releases to land must meet EA water quality limits which are consistent the LPD release limits.

Further requirements for LPD and hydrotest water releases are described in the Land Release Management Plan (Q-LNG01-15-MP-0354).

5.2.6 Release to Surface Waters

Australia Pacific LNG is authorised by the Spring Gully EA to release treated CSG water to EurombahCreek at a maximum rate of 10.2 ML/d (and 700 ML in any calendar year).

The Spring Gully EA includes water quality limit levels which are compared to monitoring at the outlet of the release pipe (the Release Point of Supply) and, for temperature difference only, at in-river locations upstream and downstream of the release pipe outlet, see Figure 3. Temperature is also monitored at the outlet of the release pipe.

6. CSG Water Quality Monitoring

6.1 Overview

Table 2 describes each monitoring component of this CSGWQMP. It identifies the locations of the monitoring points (termed Points of Supply), the relevant approval document and the SOP followed during sampling.

Sampling procedures accord with the Monitoring and Sampling Manual 2009 (DEHP 2013).

Responsibilities for sampling are defined in the Production Operations Compliance Water Quality Monitoring Plan (3675645).

Figure 3 illustrates the location of the Points of Supply in the CSG water management system.

Table 2: Spring Gully CSG Water Quality Monitoring Program Components

MonitoringComponent

Monitoring Point

LatitudeA

LongitudeA

Approval Sampling Procedure

Treated CSG Water - Project Activities: Landscaping and Revegetation

Permeate Tank Point of Supply

-25°59'59.01''

149°04'12.83''General BUA

Collect samples and complete routine analysis (3677461)

Treated CSG Water - Aquifer Injection

Aquifer Injection Point of Supply

-25°59'58.19''

149°04'14.37''Spring Gully EA

Treated CSG Water - Irrigation

Agriculture Point of Supply

-25°59'56.51''

149°04'15.04''General BUA – Irrigation

Treated CSG Water - Stock Watering and Incidental Land Management

Agriculture Point of Supply

-25°59'56.51''

149°04'15.04''

General Beneficial Use Approval – Associated Water (including coal seam gas water) (DEHP 2014a)

Untreated CSG Water – Release to land

LPD

Hydrotest water release point

NA Spring Gully EA

Low Point Drain Water Quality Sampling – LNG Procedure (3675692)

Land Release Management Plan (Q-LNG01-15-MP-0354)




MonitoringComponent

Monitoring Point

LatitudeA

LongitudeA

Approval Sampling Procedure

Treated CSG Water – Release to Surface Water

Release Point of Supply

-26°00'07.26''

149°04'56.51''

Spring Gully EA

Collect samples and complete routine analysis (3677461)

Upstream Temperature Logger

-26°00'19.21''

149°05'35.34''

Monitor the upstream and downstream temperature at the treated permeate release point, Eurombah Creek Procedure (3677519)

Downstream Temperature Logger

-26°00'14.42''

149°05'38.35''

Table Notes

A Coordinate System – GDA-MGA (UTM with GRS80 ellipsoid) Zone 55

Figure 3: Spring Gully CSG Water Quality Monitoring Points (Points of Supply)




7. Water Quality Parameters and Limit Levels

Table 3 outlines the water quality parameters to be sampled, their limit levels and their sampling frequencies for each of the monitoring components covered by this CSGWQMP.

7.1 Assumptions and Limitations

7.1.1 Irrigation

For all parameters other than pH, sodium adsorption ratio and electrical conductivity (EC), in the event that three (3) consecutive monthly samples record parameter concentrations less than 50% of the water quality limit level, subsequent sampling of that parameter will occur once every six (6) months. If future samples exceed 50% of the limit level, monthly sampling will be reinstated.

The water quality limit level for boron is dependent on the crop being irrigated and is defined in Table 9.2.18 of the Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC and ARMCANZ 2000) (the ANZECC Guideline).

Australia Pacific LNG adopts a conservative boron limit level of 2.0 mg/L, identified by the ANZECC Guideline as appropriate based on literature review and recent studies, and will monitor Pongamia pinnata for signs of boron toxicity in accordance with the Spring Gully Agriculture Resource Management Plan (Q-8200-15-MP-1086).

7.1.2 Stock Watering and Incidental Land Management

Water quality monitoring parameters for stock watering and incidental land management are based on Tables 4.3.1, 4.3.2 and 4.3.3 of the ANZECC Guideline, as required by the General BUA.

For all parameters other than total dissolved solids (TDS), in the event that three (3) consecutive monthly samples record parameter concentrations less than 50% of the water quality limit level, subsequent sampling of that parameter will occur once every six (6) months. If future samples exceed 50% of the limit level, monthly sampling will be reinstated.

The water quality limit levels for stock watering assume that water from the Agriculture Point of Supply is used to water beef cattle only and that cattle feed contains no heavy metals or metalloids.

7.1.3 Project Activities - Landscaping and Revegetation

In addition to the water quality limit levels for TDS and pH specified in Table 3, it is a requirement of the General BUA that water used for landscaping and revegetation must not contain any substances in concentrations that may be toxic to plant growth.




Table 3: Spring Gully Water Quality Monitoring Parameters

Parameter Unit

Irrigation AStock Watering and Incidental Land Management B

Aquifer Injection D Surface Water Release D Land Releases DProject Activities:

Landscaping & Revegetation B

Limit Level Frequency Limit Level C Frequency Limit Level Frequency Limit Level Frequency Limit Level Frequency Limit Level Frequency

Monitoring Procedure Collect samples and complete routine analysis – Water Treatment Facility – Spring Gully (3677461)

Sampling Point Agriculture Point of Supply Agriculture Point of SupplyAquifer Injection Point of Supply


Except Temperature Difference K

Minimum 5 LPDs normally drained

Hydrotest Water release point


Physical-Chemical

Dissolved oxygen mg/L 0.5 H * 2 I W

Electrical conductivity E µS/cm 950 F I & F * 460 H *370 J

D 2,900 N Q425

Hardness (as CaCO3) mg/L Monitor only Q

pH - 6.0 – 8.5 G I & F * 6.5 – 8.5 H * & Q 6.5 – 9.0 D 6.5 – 8.5 Q 6.0 – 9.5 I & F *

Temperature °C Monitor only H * & Q Monitor only D

Temperature difference °C +/- 2 K D

TDS E mg/L 4,000 H I & F *300 J H *

1,000 I & F *Monitor only Q

Turbidity NTU 50 W

Wellhead pressure kPa 3,700 H *

Nutrients

Ammonia mg/L 0.5 A

Nitrogen mg/L 35 Q

Phosphorus mg/L 10 Q

Major Cations and Anions

Alkalinity (Carbonate and Bicarbonate)

mg/L Monitor only Q Monitor only W

Bromide mg/L 7 A

Calcium mg/L 5 I D

Chloride mg/L 175 W 800 Q

Cyanide mg/L 0.08 A

Fluoride mg/L 2 M/S L 2 M/S L Monitor only Q 1.5 A 2 Q

Iodide mg/L Monitor only Q 0.1 A

Magnesium mg/L Monitor only Q

Potassium µg/L Monitor only Q

Sodium mg/L Monitor only Q 115 W

Sodium adsorption ratio - 6 F I & F Monitor only W




Parameter Unit












Sulphate mg/L Monitor only Q5 W

500 A

Metals and Metalloids (total and dissolved)

Aluminium µg/L 20,000 M/S L 5,000 M/S L Monitor only Q 200 A 20,000 Q

Antimony µg/L Monitor only Q

Arsenic µg/L 2,000 M/S L 500 M/S L Monitor only Q 10 A

Barium µg/L Monitor only Q 700 A

Beryllium µg/L Monitor only Q

Boron µg/L 2,000 M/S L 5,000 M/S L Monitor only Q800 W

500 Q4,000 A

Cadmium µg/L 50 M/S L 10 M/S L Monitor only Q 2 A 50 Q

Chromium µg/L 1,000 M/S L 1,000 M/S L Monitor only Q 50 A 1,000 Q

Cobalt µg/L 100 M/S L 1,000 M/S L

Copper µg/L 5,000 M/S L 1,000 M M/S L Monitor only Q 2,000 A 5,000 Q

Iron µg/L 10,000 M/S L Monitor only Q 300 A 10,000 Q

Lithium µg/L 2,500 M/S L

Lead µg/L 5,000 M/S L 100 M/S L Monitor only Q 10 A 5,000 Q

Manganese µg/L 10,000 M/S L

Monitor only Q 500 A 10,000 Q

Mercury µg/L 2 M/S L

2 M/S L

Monitor only Q 1 A 2 Q

Molybdenum µg/L 50 M/S L

150 M/S L

Monitor only Q 50 A

Nickel µg/L 2,000 M/S L 1,000 M/S L Monitor only Q 20 A 2,000 Q

Selenium µg/L 20 M/S L Monitor only Q 10 A 50 Q

Silver µg/L Monitor only Q 5,000 Q

Strontium µg/L 4,000 A

Tin µg/L Monitor only Q

Vanadium µg/L 50 A 500 Q

Uranium µg/L 200 M/S L

Zinc µg/L 5,000 M/S L 20,000 M/S L Monitor only Q 3,000 A 5,000 Q




Parameter Unit












Radiological

Alpha and Beta Emitters Bq/L 0.5 A

Gross alpha Bq/L 0.5 M/S L

Gross beta (excluding K-40)

Bq/L 0.5M/S L

Radium 226 Bq/L 5 M/S L

Radium 228 Bq/L 2 M/S L

Uranium 238 Bq/L 0.2 M/S L

BTEX

Benzene mg/L 0.001 A

Toluene mg/L 0.8 A

Ethylbenzene mg/L 0.3 A

Xylene (all isomers) mg/L 0.6 A

Other

Bromoform µg/L 100 A

Bisphenol A µg/L 200 A

Nonylphenol µg/L 500 A

PAH (as B(a)P TEF) µg/L

0.01 A

Species

Benz[a]anthracene

Benzo[b+j]fluoranthene

Benzo[k]fluoranthene

Benzo[a]pyrene

Chrysene

Dibenz[a,h]anthracene

Indeno[1,2,3 cd]pyrene

TEF

0.1

0.1

0.1

1.0

0.01

5.0

0.1

Total Coliforms Monitor only S

Sulfate Reducing Bacteria or Iron Fixing Bacteria

Monitor only S

Total Petroleum Hydrocarbons

µg/L 200 A 10,000 Q

Silica mg/L Monitor only Q




Parameter Unit












Sampling Frequency Legend:

I – Sample on commencement of activity, H – Hourly average, D – Daily, W – Weekly, F – Fortnightly, M – Monthly, Q – Quarterly, S – Six-monthly, A – On first release day of each calendar year (this monitoring relates to the protection of public health).

Table Notes

* In-line monitoring is appropriate for these parameters where equipment is installed, maintained and operated in proper and effective condition.

A Water quality limit levels for irrigation as stated in General Beneficial Use Approval – Irrigation of Associated Water (including coal seam gas water) (DEHP 2014).

B Water quality limit levels as stated in General Beneficial Use Approval – Associated Water (including coal seam gas water) (DEHP 2014).

C Water quality limit levels for stock watering assume that stock feed contains no heavy metals.

D Water quality limit levels as stated in the Spring Gully EA.

E Total dissolved solids may be estimated from electrical conductivity and vice versa using the conversion procedure outlined in the ANZECC Guideline (page 4.3-4).

F As a 95th percentile over a one-year period.

G Accounting for atmospheric equilibrium as a 95th percentile over a one-year period.

H For beef cattle. Other limits apply for dairy cattle and other livestock.

I Minimum.

J Maximum as twelve months daily average calculated each year by the EA anniversary date and reported in the annual CSG water evaluation.

K Maximum temperature difference between a near field downstream monitoring point and an upstream monitoring point.

L In the event that three (3) consecutive monthly samples record parameter concentrations less than 50% of the water quality limit level, subsequent sampling of that parameter will occur once every six (6) months. If future samples exceed 50% of the limit level, monthly sampling will be reinstated.

M For cattle. Other water quality limit levels apply for other livestock.

N For LPD releases, EC greater than 2,000 µS/cm is not authorised to be released to land.




8. Sample Analysis and Data Management

The SOP Collect Samples and Complete Routine Analysis (3677461) describes how sampled data will be analysed.

The Production Operations Compliance Water Quality Monitoring Plan (3675645) outlines responsibilities for these activities.

All data collected in support of this CSGWQMP is stored on SharePoint or in ESdat.

ESdat is Australia Pacific LNG’s environmental data management system, a centralised database used to plan, collect, import, validate, analyse and report field and laboratory environmental data. All monitoring results are stored for a minimum of five (5) years, and will be made available to the administering authority on request.

9. Reporting and Incident Response

Australia Pacific LNG will prepare routine reports describing the results of the monitoring outlined in this CSGWQMP, preferably in spreadsheet format on a monthly/quarterly basis as relevant.

Routine monitoring related to the Spring Gully EA will be summarised in the EA annual return.

No routine reporting is required under the General BUA or Irrigation General BUA however monitoring results will be referenced in annual compliance reviews.

This CSGWQMP defines an incident as a validated exceedance of a water quality limit level specified in Table 3.

All potential incidents are reviewed, validated, responded to and, where required, notified and reported to the administrating authority in accordance with the SOP Report a Non-Compliance (3676266) and the LNG Environmental Incident Procedure (3675694). All incident response processes are recorded and closed out through the Origin Collective Intelligence System (OCIS).






Title Name/s

IG-Operations-APLNG-HSE Stuart Fletcher, Andrew Beckman, Greg Wicks, Adrian Woehrle

DOCUMENT AUTHOR

Position Name

Water Analyst (original) Janelle Murray, Alex Lane

Senior Environmental Advisor –Water

Veronica Cavanough

STAKEHOLDERS AND OTHER CONTRIBUTORS

Position Name

Spring Gully Water Treatment Facility Lead

Brian Doyle, Charlie Suggate

DOCUMENT HISTORY

Rev Date Changes made in document Reviewer/s Consolidator Approver

0 29/06/11 Issued to DERM DC Janelle Murray

SM

1 28/08/14 Issued for use Kristy Presley

Alex Lane Mike Renfree

2 03/03/15 Issued for use Kristy Presley

Alex Lane Mike Renfree

3 10/10/16 Updated with low point drain release monitoring, injection monitoring requirements and discharge release volumes

Gavin Bryant Veronica Cavanough

Stuart Fletcher

4 07/09/2017 Document reviewed and updated

Veronica Cavanough

Veronica Cavanough

Stuart Fletcher




Appendix C Spring Gully Receiving Environment Monitoring Program – Eurombah Creek (CDN 8600568)

PlanQLD 8200 ENV PLN

CDN/ID 8600568

THE THREEWHATS

What can go wrong?What could cause it to go wrong?What can I do to prevent it?


Review frequency: 3 years

For internal Origin use and distribution only.Subject to employee confidentiality obligations.


Integrated Gas

SPRING GULLY RECEIVING ENVIRONMENT MONITORING PROGRAM: EUROMBAH CREEKThis Program has been prepared to comply with Receiving Environment Monitoring Program conditions of the Spring Gully Environmental Authority EPPG00885313.

Review record

Rev Date Reason for issue Reviewer/s Consolidator Approver

2 22-03-2013Amended to address recommendations DEHP and the annual report

FRC Environmental

JRM JL

3 8-08-2014Amended to address recommendations from the REMP 2013 Annual Report.

MCR KP JL

4 24/02/2017

Amended to include site specific WQOs, SGSW7 and address recommendations in the 2014-2016 annual reports and NRA review dated 13/7/15.

NRA

Veronica Cavanough

Veronica Cavanough

Stuart Fletcher

4A 10/11/2017 Issued for review NRAVeronica Cavanough

5 21/11/2017Amended to include monitoring of the White-Throated Snapping Turtle

- -Adrian Woehrle

Spring Gully Receiving Environment Monitoring Program - Eurombah Creek CDN/ID 8600568

Released on 21/11/2017 - Revision 5 - Status Issued for ruseDocument Custodian is IG-Operations-APLNG-HSE

Origin Energy Upstream Operator Pty Ltd ABN 67 105 423 532 Page 2 of 54Once printed, this is an uncontrolled document unless issuedand stamped Controlled Copy or issued under a transmittal.Based on template: AUS 1000 IMT TMP 4881989_Revision 2_IFU_03/03/2016_IG-SystemsInfo-DocRecordsMgt

Summary of Monitoring

This program has been prepared by Australia Pacific LNG and is an update of the previous Receiving Environment Monitoring Program (REMP) (i.e. Rev 3 dated 08/08.2014). It sets out the proposed design of the REMP for discharge of treated water into Eurombah Creek from Spring Gully Water Treatment Facility (WTF), andis based on results from past REMP monitoring for Spring Gully WTF and recommendations made in the REMP 2013 - 2015 Annual Reports. Revisions to the REMP design are based on the principle of continuous improvement. The aims of the REMP are to monitor and record the effects of the release of treated water on the receiving environment and identify and describe the extent of any potentially adverse environmental impacts to local environmental values.

Australia Pacific LNG Pty Limited (Australia Pacific LNG, formerly Origin) commenced continuous discharge of up to 12.7 ML/d of treated coal seam gas (CSG) water to the Eurombah Creek, via a 1.5 km natural drainage channel known as ‘Eastern Gully’, from the Spring Gully Water WTF in late December 2007. Authority to discharge occurs under Environmental Authority EPPG00885313 which was:

Amended in March 2014 to allow for discharge until 15 March 2015 (of up to 8.5 ML/d) and then

Amended in March 2015 to allow for discharge until 31 March 2020 (of up to 10.2 ML/d).

Table 1 provides a summary of the monitoring program.

Table 1 Summary of the proposed receiving environment monitoring program for the Spring Gully discharge to Eurombah Creek

Parameter Sampling Site Sampling Method Sampling Frequency

Surface Water Quality

Physico- chemical Temperature, pH, conductivity, dissolved oxygen, turbidity

Receiving Environment Sites:

5 sites downstream

Control Sites:

4 sites upstream

Hand-held water quality meter

Four times per year (notionally summer, spring, autumn and winter)

Nutrients total nitrogen and total phosphorus (unfiltered) and ammonia (as N), nitrate (as N), nitrite (as N), FRP (as P) (filtered)

One surface water sample at each site; collected from approximately 1 m from the bank edge, 30 cm below the water’s surface, by a sampling pole with clamp; analysed by a NATA-accredited laboratory

Major Cations and Anions Ca, K, Mg, Na, Cl, SO4, carbonate, bicarbonate, hydroxide

Contaminants total (unfiltered) and dissolved Al, As, Ba, B, Cd, Cr, Cu, Ga, Fe,, Mn, Mo, Ni, U, V, Zn, F and Si

Other TSS, TDS, hardness, SAR

Biological

Zooplankton Abundance of microcrustaceans –indicator of successful calcium augmentation


5 sites downstream

Control Sites:

4 sites upstream

Six samples collected at each site; 6 m depth-integrated haul with plankton net (30 cm diameter opening, 150 µm mesh) at each site


Aquatic Variety and abundance of aquatic Samples collected using modified Four times per year





macroinvertebrates macroinvertebrates AUSRIVAS sampling in bed (5 samples) and edge habitat (5 samples); 30 x 30 cm area of substrate disturbed and sampled using triangular-framed sampling net (250 µm mesh).

(notionally summer, spring, autumn and winter)

Phytoplankton biomass Chlorophyll-a One surface water sample at each site; collected from approximately 1 m from the bank edge, 30 cm below the water’s surface, by a sampling pole with clamp; analysed by a NATA-accredited laboratory.


White-throated Snapping Turtle (Elseya albagula)

White-throated Snapping Turtle Two hour visual observation period from bank. Turtle species, size and sex recordedwhere these attributes can be determined.


Stream Flows Flow rate All field monitoring locations Timed float In conjunction with field monitoring

Bed and Bank Stability Bed and Bank Stability All field monitoring locations The stability of beds and banks will be inspected during field sampling with a photographic record maintained.

In conjunction with field monitoring

Aquatic Habitat Aquatic habitat including (but not limited to) stream width, wetted width, flow, depth, substrate and proportion of habitat types in reach


5 sites downstream

Control Sites:

4 sites upstream

Data sheets based on AUSRIVAS and State of the Rivers protocols


Stream Sediment Quality

Physical particle size distribution, pH


5 sites downstream

Control Sites:

4 sites upstream

Stream sediment will be collected from the top 0.30 m of bed and bank sediment using a stainless steel trowel; analysed by a NATA-accredited laboratory


Cations and anions Ca, K, Mg, Na, Cl, SO4, carbonate, bicarbonate, hydroxide, SAR

Nutrients Total nitrogen, total phosphorus, ammonia (as N), nitrate (as N), nitrite (as N), TKN (as N)

Contaminants Total recoverable metals As, Ba, B, Cd, Cr, Cu, Ga, Mn, Mo, Ni, U, V, Znand F




Table of contents

Summary of Monitoring 2

1. Introduction 7

1.1 Scope 7

1.2 Technical Studies 9

1.2.1 Survey Reports 91.2.2 Existing Eurombah Creek REMP Monitoring Reports (at time of publication) 91.2.3 Additional Relevant Reports 10

1.3 Revision Summary 11

2. Receiving Environment 12

2.1 Location 12

2.2 Climate 13

2.3 General Description 13

2.4 Rainfall and Natural Flow 14

2.4.1 Hydraulic Capacity 16

2.5 Surface Water Quality 17

2.6 Geomorphology 17

2.7 Riparian Zone 18

2.8 Aquatic Habitat 18

2.9 Aquatic Fauna and Flora 18

2.9.1 Aquatic fauna 192.9.2 Terrestrial Fauna 222.9.3 Algae 242.9.4 Terrestrial Flora 24

3. Environmental Values 26

4. Water Quality Objectives 27

5. Monitoring Program 31

5.1 Location of Monitoring Points 31

5.2 Experimental Design 33

5.3 Aquatic Flora and Fauna 33

5.3.1 Aquatic Macroinvertebrates 335.3.2 Zooplankton and Calcium Augmentation 345.3.3 Phytoplankton 355.3.4 Fish 355.3.5 White-throated Snapping Turtle 35

5.4 Surface Water Quality 36

5.4.1 Quality Assurance and Quality Control 36

5.5 Stream Flow and Hydrology 38

5.5.1 Metering of Discharge 385.5.2 Stream Flow 385.5.3 Rainfall 38

5.6 Bank Stability and Erosion 38

5.7 Stream Sediment Quality 39

5.7.1 Quality Assurance and Quality Control 40

5.8 Aquatic Habitat 40

5.9 Field Observations 41

5.10 Monitoring of Unplanned Releases to the Watercourse 41

5.11 Data Analysis 42

5.11.1 Aquatic Macroinvertebrates and Zooplankton 425.11.2 Surface Water Quality 425.11.3 Stream Sediment Quality 43




5.11.4 White-throated Snapping Turtle 43

6. References 43


Table of figures

Figure 1 Spring Gully Development Area Tenements 12

Figure 2 Catchment areas 14

Figure 3 Estimated periods of significant flow (>1 m3/s) in Eurombah Creek at Spring Gully 16

Figure 4 REMP Monitoring Sites 32

Figure 5 Eurombah Creek spate 46

Figure 6 Eastern Gully: inflowing treated CSG water 46

Figure 7 Treated CSG water outlet: Eastern Gully 46

Figure 8 Flow & riffle ecosystem in Eastern Gully 46

Figure 9 Cattle damage & poor riparian zone 46

Figure 10 Discharge created connection downstream pools 46

Figure 11 Upstream pool: start of dry season 47

Figure 12 Same pool: shrinkage a few months later 47

Figure 13 Upstream pool: start of dry season 47

Figure 14 Same pool: dry 47

List of tables

Table 1 Summary of the proposed receiving environment monitoring program for the Spring Gully discharge to Eurombah Creek 2

Table 2 Sections of REMP Where EA Conditions are Addressed 7

Table 3 Summary of Revision Changes 11

Table 4 Estimated annual flows (ML) in Eurombah Creek at Spring Gully 14

Table 5 Estimated monthly flows (ML) in Eurombah Creek at Spring Gully 15

Table 6 Criteria for HEC-RAS modelling: Eastern Gully and Eurombah Creek 16

Table 7 Background water quality for Eurombah Creek (data from April 2003 to August 2009 excluding first discharge trial) 17

Table 8 Non-insect aquatic macroinvertebrates 19

Table 9 Insect aquatic macroinvertebrates 20

Table 10 Zooplankton 21

Table 11 Fish 22

Table 12 Amphibians, reptiles and mammals 22

Table 13 Water Birds 23

Table 14 Riparian Flora 24

Table 15 Water Quality Objectives 28

Table 16 Monitoring access locations: Eurombah Creek 31

Table 17 Receiving surface water quality monitoring for continuous discharge 37

Table 18 Bed and Bank Stability Monitoring Program 39




Table 19 Aquatic Habitat Monitoring Program 41

List of appendices

Appendix A Photos 46

Appendix B Summary of REMP Control Sites Surface Water Quality Results from August 2011 to 2015 (NRA, 2016) 48

Appendix C Introduction to the Proposed Data Analysis 52

C.1. Aquatic Macroinvertebrate Indices 52

C.2. Taxonomic Richness 52

C.3. PET Richness 52

C.4. SIGNAL 2 Scores 52

C.5. Multivariate Analyses 52

C.6. Non-Metric Multi-dimensional Scaling (nMDS) 53

C.7. Analysis of Similarities (ANOSIM) 53

C.8. Similarity Percentage – Species Contributions (SIMPER) 53

C.9. BIOENV 53

C.10. PERMANOVA, PCO and DSTLM 54

C.11. References 54




1. Introduction

Australia Pacific LNG Pty Limited (Australia Pacific LNG, formerly Origin) commenced continuous discharge of up to 12.7 ML/d of treated coal seam gas (CSG) water to Eurombah Creek, via a 1.5 km natural drainage channel known as ‘Eastern Gully’, from the Spring Gully Water Treatment Facility (WTF) in late December 2007. Authority to discharge occurs under Environmental AuthorityEPPG00885313 which allows for discharge until 31 March 2020 (of up to 10.2 ML/d).

It is a condition of the Spring Gully Environmental Authority (EA) (EPPG00885313 – B22) that a Receiving Environment Monitoring Program (REMP) be prepared and implemented. This program has been prepared by Australia Pacific LNG and is an update of the previous Receiving Environment Monitoring Program (REMP) (i.e. Rev 3 dated 08/08/2014). It sets out the proposed design of the REMP for discharge into Eurombah Creek from Spring Gully Water Treatment Facility (WTF), and is based on results from past REMP monitoring for Spring Gully WTF and recommendations made in the REMP 2013 - 2015 Annual Reports. Revisions to the REMP design are based on the principle of continuous improvement. The aims of the REMP are to monitor and record the effects of the release of treated water on the receiving environment and identify and describe the extent of any potentially adverse environmental impacts to local environmental values (EVs).

1.1 Scope

Condition (B24) of the EA specifies the requirements which this REMP must address. These are summarised in Table 2 and cross references to where each requirement is addressed in this program. It should be noted that this REMP does not address receiving environment monitoring for pond overflow, surface water run-off, seepage from storage ponds, and discharge of untreated CSG water or materiality testing. The sampling and analysis of surface water quality parameters for the protection of EVs (drinking water) in the Dawson River are not covered by this REMP as it relates only to local EVs.

Table 2 Sections of REMP Where EA Conditions are Addressed

Condition (B24) of EPPG00885313 Section of REMP Where Condition is Addressed

(a) A description of potentially affected receiving waters including key communities and background water quality characteristics based on accurate and reliable monitoring data that takes into consideration any temporal variation (e.g. seasonality);

Section 2 Receiving Environment

(b) A description of applicable environmental values, including but not limited to:

I. hydrology (flow, duration, periodicity, connectivity with groundwater systems;

II. physiochemical properties;

III. aquatic ecosystem parameters including flow and fauna habitat; and

IV. geomorphological features.

Section 3

Environmental Values

(c) A description of water quality objectives to be achieved (i.e. as scheduled pursuant to the Environmental Protection (Water) Policy 2009);

Section 4 Water Quality Objectives

(d) Any relevant reports prepared by other governmental or professional research organisations that relate to the receiving environment within which the REMP is proposed;

To the best of Australia Pacific LNG’s knowledge no studies of Eurombah Creek are currently available apart from those commissioned by Origin: listed in Section 1.2

(e) Water quality targets within the receiving environment to be achieved, and clarification of contaminant concentrations or levels indicating adverse environmental impacts during the REMP.

Section 4 Water Quality Objectives

(f) Monitoring for any potential adverse environmental impacts caused by the release including impacts to bank stability and erosion;

Section 5.6 Bank Stability and Erosion





(g) Monitoring of stream flow and hydrology; Section 5.5 Stream Flow and Hydrology

(h) Monitoring and assessment of the banks and beds of the receiving environment for SAR and an assessment of bank soil / bed sediment erosion;

Section 5.7 Stream Sediment Quality; Section 5.6 Bank Stability and Erosion

(i) Monitoring of contaminants should consider the limits specified in Schedule B, Table 2 (of the Spring Gully Environmental Authority EPPG00885313) to assess the extent of the compliance of water quality parameters and/or the ANZECC & ARMCANZ 2000 guidelines for slightly to moderately disturbed ecosystems;

Section 5.3.5 Fish

Section 5.4 Surface waterQuality

(j) Monitoring of physico-chemical parameters as a minimum those specified in Schedule B, Table 2 – Contaminant Release Limits for Release Point (in addition to dissolved oxygen saturation);

Section 5.3.5 Fish


(k) Maintain an aquatic invertebrate monitoring program in accordance with the AUSRIVAS methodology and a program to metals/metalloids in sediments (in accordance with ANZECC & ARMCANZ 2000, A Guide To The Application Of The ANZECC & ARMCANZ Water Quality Guidelines In The Minerals Industry (BATLEY et al) and/or the most recent version of AS5667.1 Guidance on Sampling of Bottom Sediments) for permanent, semi-permanent water holes and water storages;

Section 5.3 Aquatic Flora and Fauna

(l) Monitoring of a selection of phytoplankton abundance and diversity species to assess health (e.g. exoskeleton density) in respect to the availability of calcium of magnesium.

Section 5.3 Aquatic Flora and Fauna

(m) The methods for analysis and interpretation of all monitoring results;

Section 5.11 Data Analysis

(n) The locations of monitoring points (including the locations of proposed background and downstream impacted sites for each release point);

Section 5.1 Location of Monitoring Points

(o) The frequency or scheduling of sampling and analysis sufficient to determine water quality objectives and to derive site specific reference values within two (2) years (depending on wet season flows) in accordance with the Queensland Water Quality Guidelines 2009. For ephemeral streams, this should include periods of flow irrespective of mine or other discharges;

Existing background data (Section 2.6 Surface WaterQuality) will be supplemented by results obtained from monitoring (Section 5.4 Surface waterQuality)

(p) Specify sampling and analysis methods and quality assurance and control;

Section 5.4.1 Quality Assurance and Quality Control

(q) Any historical data sets to be relied upon; Section 2.5 Surface WaterQuality, Section 2.8 Aquatic Habitat, Section 2.9 Aquatic Fauna and Flora

(r) Description of the statistical basis on which conclusions are drawn;


(s) Any control or reference sites; and Section 5.1 Location of Monitoring Points





(t) Recording of planned and unplanned releases to watercourses, procedures for event monitoring, monitoring methodology used and procedure to establish background surface water quality.

Section 5.10 Monitoring of Unplanned Releases to the Watercourse.



Section 5 Monitoring Program

1.2 Technical Studies

The following subsections present relevant previous studies considered in the REMP design.

1.2.1 Survey Reports

1. Environmental Resources Management Australia, 2003c. Spring Aquatic Survey of Eurombah and Scott Creeks.

2. Environmental Resources Management Australia, 2004. Continuous Discharge Option for Spring Gully Coal Seam Gas Field Supplementary Report for Discharge Capacity.

3. EECO, 2007a. Spring Gully Coal Seam Gas Field Assessment of Discharging Reverse Osmosis Water Permeate to Eurombah Creek.

4. EECO, 2007b. Eurombah Creek RO Discharge: Pre-discharge Assessment of Macroinvertebrates.

5. EECO, 2008a. Eastern Gully River She-Oaks (Casuarina cunninghamiana).

6. Lewis Ecological Surveys, 2009. Spring Gully: Flora, Fauna & Aquatic Monitoring Program.

7. Boobook, 2017. Fauna Survey Report Survey for White-throated Snapping Turtle (Elseya albagula) at Eurombah Creek, Spring Gully Gas Field. Boobook Ecological Consulting.

1.2.2 Existing Eurombah Creek REMP Monitoring Reports (at time of publication)

1. EECO, 2007c. Eurombah Creek RO Discharge Assessment: Pre-discharge Monitoring of Macroinvertebrates.

2. EECO, 2008b. Eurombah Creek RO Discharge Assessment: Pre- and post-discharge Monitoring of Macroinvertebrates.

3. EECO, 2008c. Eurombah Creek RO Discharge Assessment: Macroinvertebrate assemblages after one year of discharge.

4. EECO, 2009a. Eurombah Creek RO Discharge Assessment: Macroinvertebrate assemblages after eighteen months of discharge.

5. EECO, 2009b. Eurombah Creek RO Discharge Assessment: supplementary assessment August 2009.

6. EECO, 2009c. Review of Water Quality Data – Spring Gully.

7. EECO, 2009d. Discharge of treated CSG water: assessment of macroinvertebrate assemblages in Eurombah Creek.

8. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report January 2012 prepared by frc environmental.

9. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report May 2012 prepared by frc environmental.

10. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report July 2012 prepared by frc environmental.

11. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report September 2012 prepared by frc environmental.

12. Eurombah Creek Aquatic Ecology Surveys: REMP Annual Report 2012 prepared by frc environmental.




13. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report January 2013 prepared by frc environmental.

14. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report March 2013 prepared by frc environmental.

15. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report May 2013 prepared by frc environmental.

16. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report July 2013 prepared by frc environmental.

17. Eurombah Creek Aquatic Ecology Surveys: REMP Interim Report September 2013 prepared by frc environmental.

18. Eurombah Creek Aquatic Ecology Surveys: REMP Annual Report 2013 prepared by frc environmental.

19. Spring Gully Receiving Environment Monitoring Program Annual Report 2014 prepared by NRA Environmental Consultants

20. Spring Gully Receiving Environment Monitoring Program Annual Report 2015 (CDN: 12556458) prepared by NRA Environmental Consultants.

21. Spring Gully Receiving Environment Monitoring Program – Eurombah Creek Interim Report Summer 2016 (CDN: 12684782).

22. Spring Gully Receiving Environment Monitoring Program – Eurombah Creek Interim Report Autumn 2016 (CDN: 12684368).

23. Spring Gully Receiving Environment Monitoring Program – Eurombah Creek Interim Report Winter 2016 (CDN: 12424624).

24. Spring Gully Receiving Environment Monitoring Program – Eurombah Creek Interim Report Spring 2016 (CDN: 12677132).

25. Spring Gully Receiving Environment Monitoring Program Annual Report 2016 (CDN: 13947082) prepared by NRA Environmental Consultants.

26. Spring Gully Receiving Environment Monitoring Program – Eurombah Creek Interim Report Summer 2017 (CDN: 13251667).

27. Spring Gully Receiving Environment Monitoring Program – Eurombah Creek Interim Report Autumn 2017 (CDN: 13958936).

28. Spring Gully Receiving Environment Monitoring Program – Eurombah Creek Interim Report Winter 2017 (CDN: 15188321).

1.2.3 Additional Relevant Reports

Environmental Resources Management Australia, 2003a. Continuous Discharge Capacity for Durham Ranch Gas Field Scoping Report.

Environmental Resources Management Australia, 2003b. Durham Coal Seam Gas Project –Creek Discharge Trial (Environmental Management Plan).

Environmental Resources Management Australia, 2004. Continuous Discharge Option for Spring Gully Coal Seam Gas Field Supplementary Report for Discharge Capacity.

Spring Gully Coal Seam Gas Field, Assessment of Discharging Reverse Osmosis Permeate to Eurombah Creek. Report No. POEN05-R01 Prepared for: Origin Energy Limited May 2007

EECO, 2009e. Discharge of treated CSG water: assessment of macroinvertebrate assemblages in Eurombah Creek.

EECO, 2010a. Zooplanktonic microcrustaceans and ambient calcium concentration in Eurombah Creek.

EECO, 2010b. Eurombah Creek: Summary of information obtained from studies and monitoring, 2003-2009.

Australia Pacific LNG, Spring Gully (PL 195, PL 200, PL 203 & PL 204) Reverse Osmosis (RO) Discharge Management Plan 2010.

Australia Pacific LNG Regional Monitoring Spring Gully Operational Area Groundwater and Eurombah Creek Monitoring FINAL Klohn Crippen Berger M09620A0 8 November 2010.




Australia Pacific LNG Pty Ltd (2010). Eurombah Creek: Summary of information obtained from studies and monitoring, 2003-2009 May 2010.

NRA, 2015. Review of the Spring Gully Receiving Environment Monitoring Program: Eurombah Creek. Letter report prepared by NRA Environmental Consultants for Australia Pacific LNG Pty Ltd, 13 July 2015.

Origin Energy, 2016. Technical Memo to respond to DEHP email dated 24/10/16 Re; Temperature. Prepared by Veronica Cavanough, 1 December 2016.

Acqua Della Vita Pty Ltd, 2016. Evaluation of boron protective concentrations for the Condamine and Dawson River release schemes and applicability to the Spring Gully CSG Water Management Scheme. Prepared by Dr Heather Chapman, 13 November 2016.

NRA, 2017, EPBC Self-Assessment Report Spring Gully Water Treatment Facility Receiving Environment Assessment of Potential Impacts, Natural Resources Assessments Pty Ltd.

NRA, 2017. EPBC Act Self Assessment Report Proposed Spring Gully CSG Water Release to Eurombah Creek Assessment of Potential Impacts, Natural Resources Assessments Pty Ltd.

NRA, 2017, Calculation of Site-specific Reference Values and Revision of the Water Quality Objectives for Eurombah Creek. Letter report prepared by NRA Environmental Consultants for Australia Pacific LNG Pty Ltd, 22 March 2017.

Acqua Della Vita Pty Ltd, 2017, Spring Gully CSG Water Management Strategy – Derivation of a protective boron concentration for Eurombah Creek CDN: 13957202. Prepared by Dr Heather Chapman, 20 October 2017.

NRA, 2017, Spring Gully REMP Autumn interim report 2017 – aquatic macroinvertebrates as a White Throated Snapping Turtle food source CDN: 13958926_01. Letter report prepared by NRA Environmental Consultants for Australia Pacific LNG Pty Ltd, 3 November 2017.

1.3 Revision Summary

A summary of changes for the latest revisions is provided in Table 3. Changes have been made by person(s) possessing appropriate qualifications and experience in the field of hydrology and surface water monitoring program design.

Table 3 Summary of Revision Changes

Revision Description of Changes

4 Collection of a single water sample and single bed and bank stream sediment samples per site as per the recommendations in the Spring Gully REMP review letter (NRA 2015).

Removal of antimony, beryllium, cobalt, lanthanum, lead, mercury, selenium and silver from the water quality parameter suite as per the recommendations in the Spring Gully REMP review letter (NRA 2015).

Removal of aluminium, antimony, beryllium, cobalt, iron, lanthanum, lead, mercury, selenium, silicon, silver, exchangeable cations, and exchangeable sodium percentage (ESP) from the stream sediment quality parameter suite as per the recommendations in the Spring Gully REMP review letter (NRA 2015).

Adoption of project-specific Water Quality Objectives (where appropriate) based on reference data from Eurombah Creek control sites and additional available data as per the Spring Gully EA.

Replacement of Control Point SGR2 with SGR2i (aka SGSW7) as a recommendation of the Spring Gully 2015 Annual REMP Report (12556458).

Identification of EVs not applicable to Eurombah Creek based on recent review.

Removal of background information not relevant to the current program for compliance purposes. Refer to previous revisions accordingly.

5 (this version)

Update to relevant Technical Studies

Addition of monitoring of the White-Throated Snapping Turtle (See Sections 2.9 and 3.5.2)




2. Receiving Environment

2.1 Location

Eurombah Creek is an ephemeral tributary of the Dawson River, the largest tributary of the Fitzroy River. The Dawson River catchment, 50,000 km2, is the largest sub-catchment (35%) of the Fitzroy River Catchment (142,000 km2). The Eurombah Creek catchment (3,000 km2) rises in the Great Dividing Ranges between Roma and Injune, reaching elevations of up to 620 m above the Australian Height Datum (AHD). The catchment drains in a generally north-easterly direction before discharging into the Dawson River approximately 80 km downstream of Spring Gully. The Spring Gully development area tenements are shown in Figure 1.

Figure 1 Spring Gully Development Area Tenements




2.2 Climate

The climate of the area is characterised by high summer daytime temperatures and summer dominant rainfall, with dry and relatively cool winters. The prevailing wind direction in the warmer months (November to March) is from the north-east and changes to a prevailing south-easterly direction during the cooler months (April to October). Average maximum temperatures for the region range from 32°C to 35°C during summer to 20°C to 23°C during winter. Average minimum temperatures range from 18°C to 21°C in summer to 3°C to 7°C during winter. Occasional frosts occur in winter months.

2.3 General Description

Eurombah Creek flows through the Spring Gully development area. It has a catchment area of about 1000 km2 at the western boundary, and about 2000 km2 at the eastern boundary (Figure 2). Durham Creek (catchment area about 160 km2) is the main tributary flowing into Eurombah Creek within the Spring Gully development area. Eurombah Creek is a semi-arid system draining cleared cattle grazing country. The region has been significantly affected by human activity for decades.

It should be noted that annual flow through the Spring Gully - Eurombah Creek system contributes about 0.1% to the average annual flow of the Dawson River (about 900 GL) and less than 0.02% (about 5,300 GL) to the annual flow in the Fitzroy River (Joo et al 2005). The median transported load of sediment from the Eurombah Creek catchment above Spring Gully is 0.99 tonnes per year (ERM, 2004). The average quantity of sediment exported from the Dawson River catchment is about 0.25 million tonnes a year: from the entire Fitzroy River catchment the average annual export of sediment is 3.09 million tonnes (Joo et al 2005). The contribution from the Eurombah Creek catchment is, in this context, minimal.

The Eurombah Creek catchment falls predominately within the Southernwood soil group. These are shallow soils (60 cm or less to bedrock) with slightly acid, sand to sandy clay loam surface horizons over acid to mildly alkaline, light to medium clay subsoils. They occur in undulating areas with average slopes of about 5% (up to 10%) under woodlands of silver-leaved or narrow-leaved ironbarks or softwood scrub. Parent materials are derived mainly from Permian sediments and acid volcanic rocks. Surface soils range from 15 to 40 cm in thickness and are greyish brown to dark greyish brown in colour. Conspicuously or sporadically bleached subsurface horizons 3-8 cm thick generally occur. Subsoils are brownish yellow, greyish brown, or reddish brown in colour and are commonly mottled. The surface soils are without structure and subsoils have a coarse subangular blocky structure. Drainage is poor. These soils are generally too shallow or steeply sloping for other than grazing use. There is a potential to form shallow water tables and allow the concentration of salts by evaporation.

Prior to European settlement the area was predominantly covered by semi-evergreen vine thickets, Brigalow and Belah shrubby open forests. There was also Ooline, Sandalwood and bottletrees present in the understorey. Most has been cleared and replaced with pastures for beef cattle and cultivated fields for grain and fodder crops.




Figure 2 Catchment areas

2.4 Rainfall and Natural Flow

Average annual rainfall is about 600 mm (maximum 1265 mm). Approximately 60% of the average annual rainfall falls during November to March. The area experiences around 6 to 8 wet days per month during summer, dropping to around 3 to 4 days during winter. Net average annual evaporation is 1380 mm.

There is one stream gauging station on Eurombah Creek (130376A Eurombah Creek at Brookfield) operated by the Department of Natural Resources and Mines (DNRM); however, flow data is not available from this station. Monthly and annual stream flows for Eurombah Creek were estimated using recorded stream flows from other gauged catchments in the area. Annual stream flows for Eurombah Creek at Spring Gully are summarised in Table 4, while monthly values are shown in Table 5.

Table 4 Estimated annual flows (ML) in Eurombah Creek at Spring Gully

Type of year Annual flow (ML)

10th percentile (very dry years) 2,200

25th percentile (dry years) 4,000

50th percentile (‘normal’ years) 10,000

75th percentile (wet years) 30,000

90th percentile (very wet years) 56,000




Table 5 Estimated monthly flows (ML) in Eurombah Creek at Spring Gully

Month 50th percentile year 75th percentile year 90th percentile year

January 620 1,400 21,400

February 900 2,670 6,190

March 25 180 1,880

April 0 23 930

May 0 130 2,160

June 0 8 1,020

July 0 0 62

August 0 0 97

September 0 0 89

October 0 81 460

November 0 270 2,860

December 17 1,630 6,320

Hydraulic conductivity was found to be approximately 10-9 m/s. Estimates suggest that between 400 and 700 ML could be lost, annually, from Eurombah Creek within the Spring Gully development areadue to seepage and evaporation.

Between flow events, the creek becomes a series of waterholes, not connected by surface flow. Anecdotal evidence suggests that a number of these are permanent; indicating that artesian springs may flow into the creek in places.

Daily stream flows were determined from daily rainfall records using the AWBM rainfall-runoff model. The model was calibrated against 35 years of records (1967 to 2001) for the Bungil Creek gauging station, and then used to generate 100 years of daily flows (1902 to 2001) for Eurombah Creek. In a 50th percentile rainfall year Eurombah Creek was predicted to carry a significant flow (>1 m3/s: ~86 ML/day) on only about 14 days (Figure 3).




Figure 3 Estimated periods of significant flow (>1 m3/s) in Eurombah Creek at Spring Gully

2.4.1 Hydraulic Capacity

Hydraulic analysis was used to assess the suitability of Eastern Gully and Eurombah Creek to receive a continuous discharge of treated water. HEC-RAS, a one-dimensional steady state hydraulic model developed by the United States Army Corp, was used for this assessment. The adopted hydraulic criteria for stream velocity, shear stress and stream power were conservative (Table 6). Manning’s coefficient for roughness of 0.035 (channels) and 0.05 (overbank areas) were used for Eastern Gully. The value 0.05 was used for Eurombah Creek.

Table 6 Criteria for HEC-RAS modelling: Eastern Gully and Eurombah Creek

Creek StabilityCriteria

Velocity (m/s) Shear stress (N/m2) Stream power N/(m

2s)

Eastern Gully Accretion <0.4 <4 <10

Stable 0.4 – 0.9 4 – 10 10 – 80

Erosion >0.9 >20 >80

Eurombah Creek Accretion <0.8 <4 <35

Stable 0.8 – 1.5 4 – 10 35 – 100

Erosion >1.5 >20 >100

In Eastern Gully, the anticipated discharge rate of 8.5 ML/day was estimated to produce a velocity about 0.8 m/s, shear stress about 20 N/m2 and stream power less than 20 N/(m2s). These values indicate that discharge was unlikely to cause erosion to rise above natural levels.

Model results for Eurombah Creek indicated that release of 35 ML/day was unlikely to cause erosion to exceed natural levels: velocity was <0.4 m/s; and both shear stress and stream power were very low (<2 & <0.5 respectively). Sediment transport loads at this discharge rate would be similar to a 50th

percentile rainfall year and about 5% of that in a 90th percentile rainfall year. The flow would cause a negligible rise in depth in Eurombah Creek.

Discharge of 8.5 ML/day would be even less likely to cause erosion. In periods of no natural flow, it was expected to: peter-out about 30 km downstream, be insignificant during spates, and provide a relatively small base-flow (downstream).




2.5 Surface Water Quality

Natural water in Eurombah Creek is dominated by four ions: calcium, sodium, bicarbonate and chloride (Table 7 and Appendix B). The relative proportions for the major ions (concentrations expressed as equivalent weights: meq/L) are: calcium 23%, sodium 17%, bicarbonate 39%, chloride 8%, magnesium 8%, potassium 3%, and sulphate about 1%.

Results from REMP surveys completed between August 2011 and November 2012 indicated that the surface water quality in Eurombah Creek was moderate (Appendix B). The concentrations of some metals (e.g. aluminium, cadmium, iron and zinc) were above the WQOs in some surveys, due to the local geology and surrounding land uses. Results from the 2013 Annual Report indicated that the discharge influenced water quality in the receiving environment on the following parameters: boron, electrical conductivity, water hardness, alkalinity, total dissolved solids, calcium, magnesium, potassium, barium and manganese. Despite the influence on these water quality parameters there was no evidence to suggest that negative impacts to aquatic fauna occurred in 2013. No discernible impacts have occurred to date based on available monitoring references.

Table 7 Background water quality for Eurombah Creek (data from April 2003 to August 2009 excluding first discharge trial)

Parameter Units Mean Std. Dev. Max. Min. n

Physico-chemical

Electrical conductivity µS/cm at 25oC 244 175 1302 103 45

pH standard 7.7 0.60 8.8 6.3 54

Dissolved oxygen mg/L 6.7 1.8 10.2 3.2 33

Temperature oC 24 6.5 33 10 28

Turbidity NTU 75 113 600 4.5 41

Major Ions

Sodium mg/L 19 11 63 11 21

Calcium mg/L 22 7.4 39 7.2 29

Magnesium mg/L 4.4 1.5 8 1.5 29

Potassium mg/L 6.3 1.6 11 3.1 16

Chloride mg/L 13 23 120 3.3 24

*Bicarbonate mg/L 113 53 350 52 30

Sulphate mg/L 2.8 2.2 8 0.5 19

Major plant nutrients

Total Nitrogen mg/L 1.3 0.9 4.7 0.7 24

**Phosphorus mg/L 0.09 0.02 0.13 0.06 9

Other Ions

Aluminium mg/L 0.9 1.0 3.7 0.02 18

Barium mg/L 0.11 0.04 0.18 0.01 23

Boron mg/L 0.039 0.008 0.049 0.025 9

Iron mg/L 0.80 0.9 3.3 0.01 18

Zinc mg/L 0.01 0.002 0.012 0.006 5

* total alkalinity (as calcium carbonate)

**Form of phosphorus not specified

2.6 Geomorphology

The main flow channel of Eurombah Creek is well incised, with typical bank heights of approximately 10 m (refer Appendix A for photographs). The low flow channel width is about 8 m. Bed sediments include layers of cracking blanket clay, a mobile sand bed with occasional mobile clay blankets and




bank mud drapes (near vertical or undercut structures) over silty sand banks. The channel bed is generally clayey and silty, with some sand bars, clear of vegetation, and may contain numerous rock outcrops and/or embedded boulders.

The channel banks are sandy and rocky, are relatively steep, contain significant stands of vegetation and, in the upper horizon, present cracking clays. Overall, it appears that there is little active bank erosion. The Eurombah Creek meander sinuosity currently appears in dynamic equilibrium for much of its length within the lease. In some places floods have created multiple, non-continuous, parallel channels, and in other places the creek bed is severely disturbed by cattle.

2.7 Riparian Zone

The dominant trees are Eucalyptus tereticornis (Queensland Blue Gum) and Angophora floribunda(Rough Barked Apple). Closer to the water Casuarina cunninghamiana (River She-Oak) is common. Canopy and sub-canopy cover ranges from mid-dense (65%) through to very sparse (15%). Median canopy height is between 18 and 26 m. The shrub layer is also sparse to very sparse. The groundcover is highly variable. Commonly, most trees are old, damaged, and in poor health. Species of riparian zone flora are listed in Table 14.

In places the riparian zone shows significant damage by cattle and is consequently in poor to very poor condition. In other places (generally steep bank areas) such damage is absent. Young trees are lacking and cattle tracks are prominent and abundant. Soil erosion in pastures and bank erosion from overland flow is evident. Weeds, such as Xanthium pungens (noogoora burr), are present in high-density patches along the riverbank.

2.8 Aquatic Habitat

Flows are infrequent, short-lived and carry high sediment loads. Soil erosion in the catchment creates a highly turbid creek. Between flows the system consists of a chain of pools (unconnected by surface flow) that progressively shrink, to dryness in some cases. In such cases the dry riverbed can be littered with dead fish and other animals. Some pools are substantial: hundreds of metres long, about 20 m wide, more than 2 m deep with rectangular cross-sectional profiles. Other, more temporary, pools are much smaller: tens of metres long, with shallow (<2 m) concave cross-sectional profiles. Immediately after spates, pools remain connected by flows in shallow, narrow, channels. Those with rock/gravel substrate constitute riffles. These connections are normally temporary. There is little overhanging or trailing terrestrial vegetation. No beds of macrophytes are present. Partially and fully submerged dead trees and branches are present in places.

During the REMP surveys in 2011 and 2012, aquatic habitat in Eurombah Creek was generally in moderate condition, with small amounts of woody debris and trailing vegetation. Monitoring sites consisted of deep, wide pools that were connected. Filamentous algae was common along the creek bed, particularly in drier months when the water level and flow rate were low.

2.9 Aquatic Fauna and Flora

A variety of surveys and monitoring programs (Section 2) have generated a partial inventory of taxa. These are listed (Table 8 to Table 14, inclusive). The lists are not intended to, and do not, indicate relative importance. The level of taxonomic detail required differed between studies; consequently some taxa are listed at high levels (phylum/class) only, whereas others are listed at the lowest levels: genus and species.

The listing is for information only. There has never been an intention (or requirement) to generate a full, or even a partial, inventory of species for Eurombah Creek. Absence of a taxon in the lists should not be interpreted as ‘not present’.

Aquatic macroinvertebrate and zooplankton communities were monitored in 2011, 2012 and 2013 as part of the REMP. During the REMP, aquatic macroinvertebrate and zooplankton communities were spatially and temporally variable, with temporal variation likely to be caused by natural seasonal fluctuations in the abundance of different taxa, and spatial variation likely to be caused by differences in habitat type and availability within each site.

Fish were not monitored for the REMP in 2011, 2012 or 2013, however a number of fish species are known to occur in Eurombah Creek, including gudgeons (Hypseleotris spp.) and saratoga (Scleropages leichardti) amongst others (Table 10).

The presence of a population of White-throated Snapping Turtle (Elseya albagula) was confirmed in Eurombah Creek, upstream and downstream of the Spring Gully WTF release point, in mid-2017 (Boobook 2017). This species is listed as critically endangered under the Environment Protection and Biodiversity Conservation Act 1999 and the Eurombah Creek population is considered to be of ‘regional and national significance’ to the species (Boobook 2017).




2.9.1 Aquatic fauna

Table 8 Non-insect aquatic macroinvertebrates

Phylum Class Order Family Genus & species

Cnidaria Hydrozoa Hydroidea Hydra

Rotifera

Platyhelminthes so Temnocephalida

Mollusca Gastropoda Ancylidae

Bithynidae

Hydrobiidae

Physidae

Thiaridae

Bivalvia Corbiculidae

Hyriidae Alathyria

Velesunio

Sphaeriidae

Annelida sc Oligochaeta

Bryozoa (Statoblasts)

Arthropoda Arachnida Acarina

(excl. insects) Crustacea

sc Ostracoda

sc Copepoda Calanoida Boeckella

Calamoecia

Cyclopoida Macrocyclops

Mesocyclops

Microcyclops

sc Branchiopoda

Cladocera Chydoridae Chydorus

Pleuroxus

Daphniidae Ceriodaphnia

Daphnia carinata

Daphnia lumholtzi

Moina

Scapholeberis kingi

Simocephalus

Macrothricidae Ilyocryptus

Macrothrix

Sididae Diaphanosoma unguiculatum

sc Malacostraca

Decapoda Atyidae Paratya australiensis

Palaemonidae Macrobrachium




Phylum Class Order Family Genus & species

Parastacidae Cherax

Isopoda Corallanidae

Nematoda

Table 9 Insect aquatic macroinvertebrates

Order Family Order Family Sub-family

Collembola Coleoptera Carabidae

Ephemeroptera

Baetidae Chrysomelidae

Caenidae Curculionidae

Leptophlebiidae Dytiscidae

Odonata Austrocorduliidae Elmidae

Coenagrionidae Gyrinidae

Cordulephyidae Haliplidae

Corduliidae Heteroceridae

Gomphidae Hydraenidae

Libellulidae Hydrochidae

Lindeniidae Hydrophilidae

Platycnemididae Limnichidae

Hemiptera Belostomatidae Microsporidae

Corixidae Nanophyidae

Dispocoridae Noteridae

Gelastocoridae Psephenidae

Gerridae Scirtidae

Hebridae Staphylinidae

Hydrometridae Diptera Ceratopogonidae

Naucoridae Chironomidae Chironominae

Nepidae Orthocladiinae

Notonectidae Tanypodinae

Ochteridae Chaoboridae

Pleidae Culicidae

Mesoveliidae Dolichopodidae

Veliidae Empididae

Neuroptera Sisyridae Ephydridae

Trichoptera Calamoceratidae Psychodidae




Order Family Order Family Sub-family

Ecnomidae Simuliidae

Hydropsychidae Stratiomyidae

Hydroptilidae Tabanidae

Leptoceridae Tipulidae

Odontoceridae Lepidoptera Crambidae

Philopotamidae

Polycentropodidae

Table 10 Zooplankton

Order Family Genus Species

Cnidaria: Hydrozoa Hydridae Hydra sp.

Rotifera: Ploimida Asplanchnidae Asplanchna sp.

Copepoda

Calanoida: Boeckella fluvialis

Boeckella triarticulata

Calamoecia lucasi

Cyclopoida: Apocyclops dengizus

Eucyclops cf. australiensis

Ectocyclops cf rubescens

Halicyclops cf. spinifer

Macrocyclops albidis

Mesocyclops sp.

Paracyclops cf. affinis

Paracyclops cf. intermedius

Thermocyclops cf. decipiens

Tropocyclops sp.

Bosminidae Bosmina meridionalis

Harpacticoida (Cladocera) Daphniidae Ceriodaphnia sp.

Daphnia lumholtzi

Daphnia carinata

Simocephalus sp.

Simocephalus gibossa

Simocephalus elizabethae

Scapholebris kingi

Chydoridae Chydorus spp.

Alona sp.

Alonella sp.




Order Family Genus Species

Leydigia cf australis

Leydigia cf. leydigia

Pleuroxus sp.

Macrothricidae Macrothrix sp.

Moinidae Moina cf. tenuicornis

Podocopida (Ostracoda) Ilyocryptidae Ilyocryptus sp.

Sidiidae Diaphanosoma cf. volzi

Candonidae Candonocypris sp.

Cyprididae Cypridopsis funebris

Cypretta bayli

Sarcypridopsis sp.

Ilyocyprididae Ilyocyprus australiensis.

Ilyocryptidae Ilyocryptus cf spinifer

Limnocytheridae Limnocythere porphyretica

Notodromadidae Newnhamia fenestrata

Sididae Diaphanosoma cf excisum

Diacypris sp.

Table 11 Fish

Family Species Common name

Ambassidae Ambassis agassizii Agassiz’s glassfish

Atherinidae Craterocephalus sterusmuscarum Fly-specked hardyhead

Clupeidae Nematolosa erebri Bony bream

*Cyprinidae Carassius auratus Goldfish

Eleotridae Hypseleotris spp.a

Common carp gudgeon

Melanotaeniidae Melanotaenia spendida Eastern rainbow fish

Osteoglossidae Sleropages leichardti Saratoga

Percithyidae Macquaria ambigua Golden perch

Plotosidae Neosilurus hyrtlii Hyrtl’s tandan

Tetrapontidae Leiopotherapon unicolor Spangled perch

* Introduced, non-native species: a pest

aIncludes undescribed Hypseleotris species that readily hybridise, together with the firetail gudgeon (which is

known to hybridise with the undescribed taxa) and the western carp gudgeon (which can only be identified with a microscope, which is not practical in field surveys)

2.9.2 Terrestrial Fauna

Table 12 Amphibians, reptiles and mammals

Class Family Species Common name

Amphibia Bufonidae Bufo marinus Cane toad

Hylidae Litoria alboguttata Striped burrowing frog

Hylidae Litoria alboguttata Striped burrowing frog




Class Family Species Common name

Litoria caerulea Green tree frog

Litoria latopalmata Broad palmed rocket frog

Litoria peronii Peron’s tree frog

Litoria rubella Desert tree frog

Myobatrachidae Pseudophryne bibroni Brown toadlet

Reptilia (o. Testudines)

Chelidae Chelodina expansa Broad-shelled river turtle

Chelodina longicollis Long-necked turtle

Elseya latisternum Saw-shelled turtle

Emydura krefftii Krefft’s river turtle

Mammalia Rodentia Hydromys chrysogaster Water rat

Table 13 Water Birds

Scientific Name Common Name

Actitus hypoleucos Common sandpiper

Anas castanea Chestnut teal

Anas gracilis Grey teal

Anas platyrhynchos Mallard

Anas rhynchotis Australasian shoveller

Anas superciliosa Pacific black duck

Ardea alba Great egret

Ardea intermedia Intermediate egret

Ardea pacifica White-necked heron

Aythya australis White-eyed duck/Hardhead

Calidris acuminata Sharp-tailed sandpiper

Calidris ferruginea Curlew sandpiper

Chenonetta jubata Australian wood duck

Chlidonias hybridus Whiskered tern

Cygnus atratus Black swan

Dendrocygna eytoni Plumed whistling duck

Egretta noveahollandiae White-faced heron

Elseyornis melanops Black-fronted dotterel

Erythrogonys cinctus Red-kneed dotterel

Fulica atra Eurasian coot

Himantopus himantopus Black-winged stilt

Larus novaehollandiae Silver gull

Limosa limosa Black-tailed godwit

Nycticorax caledonicus Nankeen night heron




Scientific Name Common Name

Malacorhynchus membranaceus Pink eared duck

Pelecanus conspicillatus Australian pelican

Phalacrocorax carbo Great cormorant

Phalacrocorax melanoleucos Little pied cormorant

Phalacrocorax sulcirostris Little black cormorant

Podiceps cristatus Great crested grebe

Poliocephalus poliocephalus Hoary-headed grebe

Recurvirostra novaehollandiae Red-necked avocet

Tachybaptus novaehollandiae Australasian grebe

Threskiornis spinicollis Straw-necked ibis

Todiramphus sanctus Sacred kingfisher

Tringa glareola Wood sandpiper

Tringa stagnatilis Marsh sandpiper

2.9.3 Algae

Occasional samples in REMP monitoring have shown the presence of: Bacillariophytes, Cyanophytes, Chlorophytes, Cryptophytes, Dinophytes, and Euglenophytes.

2.9.4 Terrestrial Flora

Table 14 Riparian Flora

Stratum Species

Canopy & sub-canopy Angophora floribunda

Eucalyptus tereticornis

Casuarina cunninghamiana

Tall shrub Juveniles of the above plus:

Acacia glaucocarpa

Acacia salicina

Alectryon diversifolius

Geijera parviflora

Grevillea striata

Low shrub Some of the above plus:

Acacia decora

Hovea longipes

Ventilago viminalis

Xanthium pungens

Groundcover Austrostipa verticillata

Aristida spp.

Bothriochloa decipiens var. Decipiens

Cenchrus ciliaris

Chloris spp.

Digitaria spp.




Stratum Species

Einadia hastate

Heteropogon contortus

Malvastrum americanum

Megathyrsus maximus var. Maximus

Paspalidium constrictum

Sporobolus creber

Sida subspicata

Themeda avenacea

Verbena aristiga

Vittadinia dissceta

Water’s Edge Alternanthera denticulate

Carex appressa

Centipedea minima

Cyperus difformis

Cyperus gymnocaulos

Juncus spp.

Ludwigia peploides ssp montevidensis

Phragmites australis




3. Environmental Values

EVs have been prescribed for Eurombah Creek in the Queensland Environmental Protection (Water) Policy 2009 (EPP Water) for the Dawson River Sub-Basin. Under the EPP Water, Eurombah Creek is included in the southern tributaries of the Upper Dawson – Taroom area. The EVs assigned to the southern tributaries, including Eurombah Creek, are:

aquatic ecosystems

irrigation

farm supply / use

stock water

human consumers

primary, secondary and visual recreation

drinking water

industrial use, and

cultural and spiritual values.

Under the EPP Water, the intrinsic biological value of aquatic ecosystems may be defined as:

unmodified or highly valued (high ecological value waters)

unmodified in terms of biological indicators, but slightly modified with respect to other indicators such as water quality (slightly disturbed waters)

adversely affected by human activity to a relatively small but measurable degree (moderately disturbed waters), or

measurably degraded and of lower ecological value than those waters described in points A – C above (highly disturbed waters).

Surrounding land-uses have impacted the waterways of the receiving environment in Eurombah Creek, however these waterways are not considered to be of lower ecological value to similar streams in the region. They should therefore be considered slightly – moderately disturbed based on the classifications in the EPP Water.

A review of the site specific EVs has been undertaken (Origin, 2016). For Eurombah Creek, the following EVs are not applicable:

Irrigation

Human consumers.




4. Water Quality Objectives

It is important to reflect on the management intent for waters, as defined in the EPP (Water), for the moderately disturbed receiving environment waters when setting site-specific Water Quality Objectives (WQOs). Section 14 of the EPP (Water) relates to waters subject to an activity that involves the release of waste water or contaminants to the waters. It states that: It is the management intent for the waters that the decision to release the waste water or contaminant must ensure the following for moderately disturbed waters

if the measures for indicators of the environmental values achieve the water quality objectives for the water—the measures for the indicators are maintained at levels that achieve the water quality objectives for the water; or

if the measures for indicators of the environmental values do not achieve the water quality objectives for the water—the measures for indicators of the environmental values are improved to achieve the water quality objectives for the water.

In summary, for parameters that already meet the WQO (ie where the waters that receive discharge have some assimilation capacity), some change in receiving water quality may be acceptable as long as the nominated environmental value is protected (ie that it does not result in a WQO being exceeded), but for parameters that do not meet the WQO, water quality should be improved and not further degraded.

The EVs applicable to Eurombah Creek were taken into account in setting the WQOs. The most conservative EV for the project relates to the protection of aquatic ecosystems, and therefore published GVs and the approach to calculating project specific reference values were applicable for the protection of aquatic ecosystem EV.

When REMP monitoring commenced in 2011, there were no local WQOs assigned to Eurombah Creek; subsequently, the Australian and New Zealand Guidelines for Fresh and Marine Water Quality Guidelines ANZECC & ARMCANZ (2000), were used as default guidelines. Project-specific reference values for Eurombah Creek have since been developed using reference data from control sites monitored in the REMP. Project-specific reference values were calculated by NRA Environmental Consultants (NRA 2017) in accordance with methods outlined in Section 4.4 of the Queensland Water Quality Guidelines (QWQGs) (DEHP 2009) and ANZECC & ARMCANZ (2000).

Once the project-specific reference values were calculated, they were compared to published GVsfrom ANZECC & ARMCANZ (2000) and DEHP (2011) to determine the most appropriate value to be adopted as the WQO for Eurombah Creek. The following decision rules were applied:

Project-specific reference values were selected in preference to Upper Dawson River Sub-basin regional GVs (DEHP 2011) based on the rationale that if both values were calculated from reference data then it is preferable to use the data most relevant to Eurombah Creek.

Where the published default GV was based on biological effects data (e.g. from laboratory based ecotoxicity tests) and was higher than the project-specific reference value the published default GV was selected over the project-specific reference value.

A project-specific reference value that is higher than a published default GV is indicative that the parameter naturally occurs at higher concentrations in Eurombah Creek. In this case, project-specific reference values were selected as WQOs to allow APLNG to manage discharge to prevent a decline in water quality in accordance with the EPP (Water). Published default GVs can be adopted as aspirational targets where water quality improvement is the management aim.

The WQOs for Eurombah Creek are presented in Table 15.

A review of the physical, hydrological and physico-chemical characteristics of Spring Gully REMP receiving sites was undertaken to determine which receiving sites should be compared to the project-specific reference values for ‘permanent’ pools and which should be compared to the values derived for ‘temporary’ pools (NRA, 2017). This review determined that water quality data from sites SGR3, SGSW20, SGSW21 and SGSW34 should be compared to site-specific RVs for ‘permanent’ pools (calculated from reference data from control sites SGSW14 and SGSW15) and data for receiving site SGSW22 should be compared to the site-specific RVs for temporary pools (calculated using reference data from SGR1).




Table 15 Water Quality Objectives

Parameter UnitsPublished Water Quality Objective/ Guideline Value1

Project-specific Reference Value (February 2017)

2 Eurombah Creek Water Quality Objective

Permanent pools Temporary pools Permanent pools Temporary pools

Physical and Chemical

dissolved oxygen % saturation 85 – 110a 54 – 85 63 – 133 54 – 110 63 – 133h

pH 6.5 – 8.5a 7.0 – 7.9 7.6 – 8.6 6.5 – 8.5 6.5 – 8.6

turbidity NTU 50a 31 58 31 58

electrical conductivity (base flow)

µS/cm 370a 669 685 669 685

electrical conductivity (high flow)

µS/cm 210a N/A N/A 210 210

suspended solids mg/L 30a 13 56 13 56

chlorophyll a µg/L 5a 6.0 6.2 6.0 6.2

Temperature °C – 15.5 – 27.7 17.5 – 26.0 ±4i ±4i

Nutrients

ammonia (as N) µg/L 20a

44 48 44 48

nitrate (as N) µg/L 60a 24 20 60 60

total nitrogen µg/L 620a 950 1380 950 1380

filterable reactive phosphorus

µg/L20a 15

515

5

total phosphorus µg/L 70a 60 148 60 148




Parameter UnitsPublished Water Quality Objective/ Guideline Value1

Project-specific Reference Value (February 2017)2 Eurombah Creek Water Quality Objective

Permanent pools Temporary pools Permanent pools Temporary pools

Major Ions

Calcium3 mg/L – >24 >21 >5 >5

sulfate mg/L 545b 3.0 3.6 545 545

Metals and Metalloids

aluminium µg/L 55c,e 40 112 55 112

arsenic µg/L 13c,f 1.7 1.4 13 13

boron µg/L 370c 41 25 1000g 1000g

cadmium µg/L 0.2c <0.2 <0.1 0.2 0.2

chromium µg/L 1.0c,f <1 <1 1.0 1.0

copper µg/L 1.4c 1.3 3.6 1.4 3.6

gallium µg/L 18d

iron µg/L 300d 85 78 300 300

manganese µg/L 1900c 32 15 1900 1900

molybdenum µg/L 34d 1.5 1.3 34 34

nickel µg/L 11c 1.0 1.3 11 11

uranium µg/L 0.5d <1 <1 0.5 0.5

vanadium µg/L 6d <10 <10 6 6

zinc µg/L 8c

25 9 25 91 Published water quality objectives are for the Upper Dawson River Sub-basin (DEHP 2011). Where no regional water quality objective was available for the Upper Dawson

River Sub-basin (eg for toxicants), DEHP 2011 defers to the ANZECC & ARMCANZ 2000 default guideline values. No default or regional guideline values are available




for temperature. Temperature varies seasonally and daily and is depth dependent, therefore, DEHP 2011 and ANZECC & ARMCANZ 2000 recommend the derivation of

local water quality objectives for temperature.2 Project-specific reference values from NRA 2017. Note that project-specific reference values are to be updated annually as new REMP data becomes available. Less than

values (ie ‘<’) indicate that the project-specific reference value was below laboratory limits of reporting.3 Values presented for calcium are minimum values (ie calcium concentrations below these values trigger a management response). Project-specific reference values for

calcium are based on the 20th

percentile of reference range data as the concern with this parameter is related to a calcium deficiency in Eurombah Creek and

subsequent effects on aquatic biota. Note that the REMP-specific WQO of 5 mg/L has been retained as per Section 5.3.2.

– No relevant WQO or source not applicable.

N/A Not applicable

NTU Nephelometric Turbidity Unitsa Water quality objective from DEHP(2011).b

Published guideline value for sulfate for the Fitzroy River Basin from Dunlop et al. (2016).c Published default moderate to high reliability guideline values from ANZECC & ARMCANZ (2000), Table 3.4.1.d Published default low reliability guideline vale or indicative working level value from ANZECC & ARMCANZ (2000), Section 8.3.7.e Published default guideline value for aluminium is for waters with pH > 6.5 (ANZECC & ARMCANZ 2000).f Published default guideline values for arsenic (V) and chromium (VI) were used as these are the most toxic forms of these parameters and thereby provide the most

conservative approach in the absence of metal speciation data.g WQO for boron is the project-specific guideline value for the Condamine and Dawson River’s derived from site-specific direct toxicity assessments (Acqua Della Vita Pty

Ltd, 2013 and Halcrow Pacific Pty Limited, 2016 respectively) that was assessed as applicable to Eurombah Creek (Acqua Della Vita Pty Ltd, 2016).h Note that DEHP (2009) recognises that dissolved oxygen concentrations naturally drop below water quality guideline values in drying pools.

i WQO for temperature is a project specific guideline value derived from Eurombah Creek temperature monitoring data (Origin, 2016) and accepted as an EA discharge

limit.




5. Monitoring Program

The Spring Gully REMP has been designed to monitor and record the effects of the release of contaminants on the receiving environment and identify and describe the extent of any potentially adverse environmental impacts to local EVs. The main objectives for monitoring are to assess changes in:

Aquatic flora and fauna;

Surface water quality;

Stream flow and hydrology;

Phytoplankton biomass;

Bank stability and erosion; and

Stream sediment quality.

5.1 Location of Monitoring Points

For the purposes of the REMP, the receiving environment is defined by EA Condition (B20) as “the waters of Eurombah Creek and includes monitoring points SGSW7 and SGSW34”.

Nine sites are monitored in the Spring Gully REMP: four control sites upstream of the confluence with Eastern Creek (where the treated CSG waters enter Eurombah Creek) and five receiving sites downstream of Eastern Creek. The locations of the REMP monitoring sites are shown in Figure 4 with co-ordinates presented in Table 16.

The replacement of control site SGR2 with control site SGR2i (aka SGSW7) was recommended by NRA as water quality data indicated that site SGR2 may be influenced by releases of treated CSG waters (NRA 2016). This recommendation has been formally adopted for REMP surveys from 2017 onwards.

Table 16 Monitoring access locations: Eurombah Creek

Site: SGSW Access Location EastingA NorthingA

SGSW14 Upstream (control) 705 243 7 121 359

SGSW15 Upstream (control) 705 709 7 121 063

SGR1 Upstream (control) 707 436 7 120 479

SGR2i (SGSW7)

Upstream (control) 708 756 7 121 333

SGR3 Downstream 709 638 7 122 232

SGSW20 Downstream 710 689 7 123 268



SGSW34 Downstream 713 537 7 123 227A

Coordinates in MGA 94, Zone 55J




Figure 4 REMP Monitoring Sites




5.2 Experimental Design

To reliably detect impacts associated with the discharges, a quantitative sampling design is required that is statistically robust, and spatially and temporally replicated. Replicated sampling enables a rigorous analysis of the variability between sites and over time, essential to determine whether discharge is impacting on the aquatic ecosystem EV of the receiving environment. Therefore, to accurately detect potential impacts from the discharge from the Spring Gully WTF throughout the REMP, a replicated sampling design will be undertaken.

Aquatic habitat surveys and sampling for physico-chemical properties, chemical composition of surface water and stream sediment, phytoplankton biomass, aquatic macroinvertebrates and zooplankton will occur four times a year (in summer, autumn, winter and spring). Precise times will depend on weather (i.e. flow) conditions.

5.3 Aquatic Flora and Fauna

Australia Pacific LNG intends to monitor the stretch of Eurombah Creek between sites SGSW14 (just upstream of the Wybara Road crossing) and SGSW34 (just downstream of the Nugget Hills road crossing). This covers about 14 km of creek: 7 km upstream and 7 km downstream of the inflow of treated water (Eastern Gully).

For most of the year Eurombah Creek does not flow. Permanent pools constitute the baseline habitat for aquatic biota. Released treated CSG water creates a chain of additional permanent pools downstream. It has been identified that once base-flow ceases, released treated CSG water progressively changes the chemical composition of water in downstream pools. Their chemical composition (eventually) differs significantly from upstream pools. Australia Pacific LNG’s main objective for monitoring is to assess whether the permanent pools created by treated CSG water have any adverse impact on resident biota.

Several upstream pools are temporary. Such habitats are hazardous systems for aquatic species: normal interactions and processes intensify and the probability of death increases as the pools shrink. Although some species are capable of surviving dry periods by migrating into the wet sediments or by creating resistant stages, not all individuals would be at an appropriate stage of development to achieve this. Survival by this strategy is not guaranteed: dry conditions might be too extended. Although adult insects could escape by flight, pre-adult stages would not have this capability. Where upstream pools have dried out it has been a common experience to find the riverbed littered with dead fish and other aquatic biota. WQOs for temporary pools have been included in this REMP based on the SGSW22 monitoring location.

5.3.1 Aquatic Macroinvertebrates

All biological monitoring programs whose focus is change in biodiversity use a surrogate indicator for assessment: it is not possible to monitor all species present in a system (ANZECC & ARMCANZ 2000). Aquatic macroinvertebrates are generally regarded as the most suitable surrogate, and sub-sets of these are universally used for routine monitoring.

Origin employed artificial substrate samplers (ASS) to monitor aquatic macroinvertebrates in Eurombah Creek between 2007 and 2013. This section provides an overview on the use of ASS at Eurombah Creek. Compared with other sampling methods use of ASS removes several sources of variance, for example: operator technique, type of substrate, area sampled, and previous history of sampled point. Normally these sources of variance are uncontrolled and render application of statistical methods invalid and confound interpretation.

Samplers previously employed by Origin were cylindrical containers 25 cm long and 12 cm diameter. The walls were constructed of stainless steel mesh (1 cm square) with an inner plastic mesh of the same dimensions. A steel base provided ballast to ensure that the sampler sat on the creek bed and had a hinged flap providing access to the interior. The other end consisted of a perforated plastic sheet and attachment points for rope. The artificial substrate consisted of 0.25 m2 of ‘knitted’ artificial fibre (mesh size 1 cm by 0.5 cm), which was inserted into the sampler. The artificial substrate samplers constructed for the REMP were slightly different to the ones previously used during monitoring in Eurombah Creek; however, they have the same surface area so the results were considered to be comparable.

Samplers were placed in position in the creek and left for 6-8 weeks before retrieval. On retrieval the contents of the sampler (substrate and animals) were removed, placed into a container, and preserved with alcohol. Animals were removed by gentle scrubbing using a soft-bristle brush and the whole sample searched under a stereomicroscope. Animals were identified and counted. Identification was to Family level for most taxa, the exceptions being: annelids, cnidarians, nematodes and mites. Quality assurance dictates that sample searching has to be conducted by a professionally qualified biologist who has extensive experience with identification and recognition of invertebrates. Most individuals




caught by this method are small, early life-history stages (some are fragmented) and not readily identified using taxonomic keys.

As per the recommendations of the REMP 2013 Annual Report, ASS’s will no longer be used to sample aquatic macroinvertebrates.

Currently in effect is AUSRIVAS-style sampling (involving collection of one sample from each habitat, at each site), designed to provide a broad description of aquatic macroinvertebrate communities. As noted in the Monitoring and Sampling Manual 2009 (DERM 2009), the sampling protocol used should be based on the objectives of the monitoring program, and may need to include replication in the sampling design. To reliably detect impacts associated with the discharges, a quantitative sampling design is required that is statistically robust, and spatially and temporally replicated. Replicated sampling enables a more rigorous analysis of the variability within and between sites, essential to determine whether the mine discharge is impacting aquatic macroinvertebrate communities downstream.

Collection of modified AUSRIVAS aquatic macroinvertebrate samples will therefore broadly follow the standard AUSRIVAS methodology (DNRM 2001; DERM 2009), with respect to habitat selection and sampling technique. However, rather than a single sample being collected from a 10 m sweep in each habitat, five aquatic macroinvertebrate samples will be collected from each habitat (expected to be bed (pool) and edge habitat) at each site, based on the number of samples recently collected for other studies in the region (e.g. the Smartrivers Project, EM 2005).

When collecting modified AUSRIVAS samples, the substrate will be disturbed within a 30 x 30 cm area for a period of five seconds, and each sample will then be collected by sweeping a standard triangular-framed aquatic macroinvertebrate sampling net (250 µm mesh) through the disturbed area five times. The samples will be transferred to zip-lock bags or screw-cap jars, preserved in methylated spirits and transported to the laboratory. Samples will be sorted, counted and identified to the lowest practical taxonomic level (in most instances family), to comply with AUSRIVAS standards and those described in Chessman (2003).

5.3.2 Zooplankton and Calcium Augmentation

Origin discovered (August 2009) that lack of calcium in treated CSG water reduced normal population growth of zooplanktonic microcrustacea in downstream pools. The concentration of calcium in treated CSG water was raised to at least 5 mg/L prior to discharge in an attempt to rectify the issue.

Lack of calcium inhibits moulting in zooplankton and affected species fail to reach adulthood and reproduce. Consequently, to assess re-establishment of reproductive populations (over a period of 4 months, September to December 2009), sampling targeted larger individuals: mainly adults of the common copepods and cladocerans. Samples were collected using plankton nets with a relatively large pore size (250 µm – Note: usual net size is 150 µm). Such nets (~30 cm diameter) were trawled 6m horizontally, just below the surface, to collect each sample. Animals were preserved in alcohol, in the field. Samples were searched using a stereomicroscope; animals identified and counted, and where necessary, random sub-samples searched and counts converted to estimates of abundance in the whole sample.

This method was designed to provide an indicator of recovery only. The main parameter of interest was catch size (total number of individuals caught for a constant effort). Species composition was determined but only as an aide for interpretation, if required. Sampling was not designed to provide estimates of population densities or complement of species in the zooplankton.

Sampling by this method was used again in July and September 2010, as part of routine monitoring to assess the effectiveness of calcium augmentation, and permit valid comparison with existing (baseline) data, and no adverse impact was detected.

When REMP monitoring began in August 2011, a similar sampling method was used, except that multiple samples were collected at each site, so that data could be analysed statistically. At each site, six depth-integrated (i.e. taken from the whole water column) samples were collected using a 150 µm net. For each sample, the net was lowered to the bottom of the creek then dragged through the water column, diagonally towards the surface, for a 6 m long tow. Samples were collected from each of the available habitats at a site (e.g. near woody debris, in edge habitat and in open water). The samples were preserved in methylated spirits in the field, and transported to the laboratory for sorting and identification. In most surveys, three samples were processed and the remaining three samples were held for further analysis.

When using this improved method, a difference between zooplankton communities in control and receiving environments was detected in several REMP surveys. The magnitude of this impact was not fully understood, because only three of the six samples collected at each site were processed (and statistical power of the analyses was not high); there were also several tributaries entering Eurombah




Creek between the furthest downstream control site (SGSW15) and the first receiving environment site (SGSW20), which meant that there may have been several other factors contributing to this difference that were not related to the discharge. In order to accurately determine whether or not the discharge was influencing zooplankton communities, it was recommended that all six samples from each site be processed (instead of three), and three new sites be added to the monitoring program.

These recommendations have been adopted by Australia Pacific LNG and are currently used in the REMP surveys.

5.3.3 Phytoplankton

Previously Origin has confined assessment of phytoplankton to visual observation. No blooms have been reported. There are no beds of macrophytes in the monitored system. In places small collections of Characeae (large green algae, attached to the substrate) are found at the water’s margin. Occasionally, filamentous algae (commonly Spirogyra sp.) have been found in plankton hauls and attached to artificial substrate sampler ropes. High turbidity and damage from cattle restrict establishment of fixed primary producers (macrophytes and algae present in periphyton).

Phytoplankton (as indicated by chlorophyll a content) will be monitored as a parameter during surface water quality sampling (see Section 5.4). If unusually large concentrations are encounteredconsistently then samples will be collected, preserved with Lugol’s iodine and sent to a NATA registered laboratory for identification and enumeration of species. Depending on results of that analysis appropriate management action will be instigated.

5.3.4 Fish

When natural flow ceases fish become trapped in pools. Between entrapment and the next flow event, each trapped population will decrease (there would be no population growth from immigration or reproduction). Decrease in population sizes may cause the relative abundance of trapped species to change from that present initially.

Pools that had similar assemblages of trapped fish, initially, might by the next flow have different assemblages. Conversely, pools that had different assemblages of fish, initially, might by the next flow have similar assemblages. This would be true for both upstream and downstream pools. For short-term monitoring, composition of trapped fish assemblages is an inappropriate indicator of potential impact. Any interpretation of data obtained is likely to be misleading.

Comparison of mortality rates would be valid for monitoring but given the conditions at Spring Gully, this is not a practicable option. Estimation would require intensive, and frequent, quantitative sampling of most (if not all) pools. The pools are inaccessible for electrofishing from boats. The pools are too large, and too dangerous (e.g. steep banks and submerged woody debris), for backpack electrofishing. Active methods for fish capture are impracticable and passive methods, apart from being non-quantitative, are too destructive both of targeted fish and non-target species (e.g. turtles).

Australia Pacific LNG has elected not to sample fish populations. Surrogates as described in Section 6.3 will be employed for monitoring and detection of impact. Australia Pacific LNG believes that the decision not to sample fish protects resident species such as Saratoga from the risk of harm caused by sampling, whilst not diminishing its ability to detect impact if it occurs.

5.3.5 White-throated Snapping Turtle

Australia Pacific LNG has elected to monitor the presence of White-throated Snapping Turtle in Eurombah Creek as part of the REMP. A ‘visual survey’ method consistent with Eyre et al. (2014) will be used. A visual survey was conducted by Boobook (2017) and it was shown to provide a reliable indication of White-throated Snapping Turtle presence in Eurombah Creek.

Turtle observations will be conducted at each REMP site before all other indicators are monitored, to avoid disturbing the turtles. This approach will increase the likelihood of individuals surfacing or basking. The visual survey method will involve two observers watching the pool using binoculars for a period of two hours. All turtle sightings will be recorded. Species names will be recorded when individuals can be positively identified. Individuals will be photographed where possible. The frequencyof White-throated Snapping Turtle sightings (as a function of the number of individual observed within the standardised time period) will provide a semi-quantitative estimate of population size. Population demographic information (i.e. size and sex1 of individuals) will be recorded, where possible, to provide information on population recruitment.

1White-throated Snapping Turtles display distinct sexual dimorphism (Thomson et al. 2006).




A walk-through survey of the stream banks over the 100 m reach at each REMP site will be undertakento search for turtle nests. The White-throated Snapping Turtle have been reported to produce eggs between the months of March and September (Hamann et al. 2007), therefore nests are more likely to be encountered during the autumn and winter surveys. Where encountered, nests will be photographed; their GPS location recorded and notes will be made regarding the nest location, whether the nest is intact or disturbed and any evidence to confirm that the nest belongs to a turtle (e.g. tracks, remains of eggs).

5.4 Surface Water Quality

Surface water quality changes in the receiving environment will be monitored in accordance with Schedule 1 Table 2 of the EA and ANZECC & ARMCANZ (2000) guidelines for slightly to moderately disturbed ecosystems. For discharges that are predominantly continuous (i.e. with regular daily discharges of similar volume), the minimum monitoring requirements are presented in Table 17.

Note: Several water quality parameters have been removed from the current REMP sampling program, as they were either routinely below the laboratory limits of reporting at all sites, and/or not associated with CSG discharge water, including:

water colour

antimony

beryllium

bismuth

cobalt

lanthanum

lead

mercury

selenium

silver

thallium

faecal coliforms

e-coli

organophosphate and organochloride pesticides

hydrocarbons (TPH, BTEX and polyaromatic hydrocarbons), and

cyanide.

5.4.1 Quality Assurance and Quality Control

Field sampling will be done by a suitably trained and competent person in accordance with Australian Standard (AS) AS5667 Water Quality Sampling, and in accordance with the Monitoring and Sampling Guidelines 2009 (DERM 2009). In summary:

hand-held water quality meters will be calibrated before the commencement of sampling, and checked while in the field (and recalibrated if necessary). A calibration record will be kept

hand-held water quality meters will be cleaned at the end of each field day

surface water samples will be collected straight into the sample bottle wherever possible, and the bottles will not be rinsed prior to sample collection

if the sample cannot be collected straight into the sample bottle, the container it is collected in (such as a bucket or other form of sampler) will be thoroughly rinsed with ambient site water to ensure is not contaminated

powderless gloves will be used when collecting all water samples, and care will be taken not to touch the inside of any sampling containers, or to place open bottles / jars or their lids onto the ground or other contaminated surfaces

a field blank will be collected from one site during each sampling event, to assess sample handling procedures. Laboratory obtained deionised water must be used for the field blank




a duplicate sample will be taken at one site to confirm analytical reliability of laboratory analysis

filtering of water samples for nutrients and metals will be done on site in the field

samples will be stored under the appropriate holding conditions for each parameter and delivered to the laboratory within the appropriate holding times (as specified by the laboratory), in accordance with the security and transport protocols outlined in the Monitoring and Sampling Manual (DERM 2009)

a chain of custody form will be completed for all samples sent to the laboratory for analysis, and

samples will be analysed by a NATA-accredited laboratory, and laboratory duplicates and blanks will be analysed in accordance with NATA-accredited protocols.

Table 17 Receiving surface water quality monitoring for continuous discharge2


Surface Water Quality

Physico-chemical

Temperature, pH, conductivity, DO, turbidity


5 sites downstream

Control Sites:

4 sites upstream

Hand-held water quality meter


Nutrients total nitrogen and total phosphorus (unfiltered) and ammonia (as N), nitrate (as N), nitrite (as N), FRP (as P) (filtered)

One surface watersample at each site; collected from approximately 1 m from the bank edge, 30 cm below the water’s surface, by a sampling pole with clamp; analysed by a NATA-accredited laboratory

Major Cations and Anions

Ca, K, Mg, Na, Cl, SO4, carbonate, bicarbonate, hydroxide

Contaminants total (unfiltered) and dissolved Al, As, Ba, B, Cd, Cr, Cu, Ga, Fe, Mn, Mo, Ni, U, V, Zn, fluoride, silicon

Other TSS, TDS, hardness, SAR

Biological

Zooplankton Abundance of large microcrustaceans –indicator of successful calcium augmentation


5 sites downstream

Control Sites:

4 sites upstream

Six zooplankton samples collected at each site; 6 m haul with plankton net (30 cm diameter opening, 150 µm mesh)


Aquatic macroinvertebrates

Variety and abundance of aquatic macroinvertebrates

Samples collected using modified AUSRIVAS sampling in bed (5 samples) and edge habitat (5 samples); 30 x 30 cm area of substrate disturbed and sampled using triangular-framed sampling net (250 µm mesh).


Phytoplankton biomass

Chlorophyll-a Two surface watersamples at each site; collected from

Four times per year (notionally summer, spring, autumn and

2 Should the nature and frequency of discharge change then the monitoring requirements may need to be adapted accordingly.





approximately 1 m from the bank edge, 30 cm below the water’s surface, by a sampling pole with clamp; analysed by a NATA-accredited laboratory

winter)

White-throated Snapping Turtle (Elseya albagula)

White-throated Snapping Turtle

Two hour visual observation period from bank. Turtle species, size and sex recorded where these attributes can be determined.


5.5 Stream Flow and Hydrology

5.5.1 Metering of Discharge

The volume of treated CSG water released to Eastern Gully will be measured using a metering device, with a record of daily discharge volumes maintained. This record will detail the daily volume released.

In the event of an unplanned release, event specific monitoring requirements will be determined, based on the nature of the event.

5.5.2 Stream Flow

Stream flow will be estimated at each monitoring site using a velocity-area method in accordance with the Monitoring and Sampling Manual 2009 (DERM 2009), either by using a portable velocity meter, or where a meter is not available at the time of sampling, by timing a float travelling over a known distance. Estimates of flow, using this method, will also be made at each sampling site during REMP monitoring events.

This data, along with rainfall data, will be obtained to aid data analysis and interpretation, and will also be compared to the volume of water released daily from the discharge location to determine if the discharge is altering flows in the receiving environment.

5.5.3 Rainfall

A record of rainfall will be established using the Bureau of Meteorology Taroom Post Office station (Station ID: 035070, Lat: -25.64, Lon: 149.80). This record will be augmented by onsite weather observations, where available.

5.6 Bank Stability and Erosion

Experience gained since discharge began in December 2007 (up to 12.7 ML/d) has identified no significant increase in erosion or bank/bed instability as a result of the discharge. The EA approveddischarge of up to 10.2 ML/d can be considered as having even less probability of causing erosion.

Given the history of discharge a comprehensive bank stability and erosion monitoring program is considered unnecessary. The stability of beds and banks will continue to be inspected as part of aquatic habitat assessments made during field sampling (see Section 5.8), and will be monitored using the Sustainable Rivers Audit physical habitat methods (MDBC, 2004). The following parameters will beassessed at each site:

bank shape

bank stability

bed stability

artificial bank protection measures

factors affecting bank stability

valley shape

channel shape, and

channel and stream width.




Results of stream sediment quality sampling for the concentration of cations and anions, and the sodium absorption ratio (SAR) will also be used to assess the likelihood of dispersion at each site (refer to Section 5.7).

In the unlikely event that evidence of bed or bank instability is detected, the bed and bank stability monitoring program, presented in Table 18, will be implemented in conjunction with management actions.

Table 18 Bed and Bank Stability Monitoring Program

Sampling Site Sampling Method Sampling Frequency

Bed and Bank Stability


5 sites downstream

Control Sites:

4 sites upstream

Detailed profiles established by surveying, sites examined for changes with photographic record & resurveying where appropriate

In conjunction with field monitoring.


5.7 Stream Sediment Quality

Stream sediment quality will be monitored up to four times per year (notionally summer, spring, autumn and winter). Monitoring of stream sediments will be done at four upstream and five downstream locations (refer to Section 5.1). Stream sediment samples will be analysed for the following parameters:

particle size distribution (sieve and hydrometer)

pH

major cations (Ca, K, Mg, Na) and anions (Cl, SO4, alkalinity) (mg/kg)

sodium absorption ratio (SAR)

fluoride (mg/kg)

nutrients (total nitrogen, total phosphorus, ammonia (as N), nitrate (as N) nitrite (as N), total Kjeldahl nitrogen (TKN)) (mg/kg)

total metals and metalloids (As, Ba, B, Cd, Cr, Cu, Ga, Mn, Mo, Ni, U, V, Zn (mg/kg),

Field sampling will be done by a suitably trained and competent person in accordance with Australian Standard (AS) AS5667.1 Guidance on Sampling of Bottom Sediments, and in accordance with the Handbook for Sediment Quality Assessment (Simpson et al. 2005).

Several stream sediment quality parameters were removed from the REMP sampling program, as they were routinely below the laboratory limits of reporting at all sites, and not associated with treated CSG water discharge, including:

bismuth

thallium

cyanide

hydrocarbons (TPH, BTEX and polyaromatic hydrocarbons), and

organochloride pesticides, and

organophosphate pesticides.

Several other parameters were removed from the REMP stream sediment parameter suite because water quality results showed that they were not associated with the treated CSG water (see NRA 2015, NRA 2016), including:

antimony

beryllium

cobalt

lanthanum

lead

mercury




selenium

Aluminium, iron and silicon were removed from the stream sediment parameter list because naturally high background concentrations of these elements in stream sediments would mask any change in concentration potentially brought about by APLNG activities (NRA 2015).

Exchangeable cationsand exchangeable sodium percentage were removed because these parameters do not provide a useful indicator of bed and bank stability. Parameters from the water quality suite (i.e. SAR, turbidity and suspended solids) are considered more useful at determining potential for stream sediment dispersion and for monitoring erosion (NRA 2015 and pers. comm. Dr Andrew Butler, Principal Environmental Scientist, NRA Environmental Consultants, email dated 16 February 2017).

5.7.1 Quality Assurance and Quality Control

Field sampling will be done by a suitably trained and competent person in accordance with Australian Standard (AS) AS5667.1 Guidance on Sampling of Bottom Sediments, and in accordance with the Handbook for Sediment Quality Assessment (Simpson et al. 2005). In summary:

stream sediment samples will be collected straight into the sample jar / bag wherever possible, and the jar / bag will not be rinsed prior to sample collection

powderless gloves will be used when collecting all sediment samples, and care will be taken not to touch the inside of any sampling containers, or to place open jars / bags or their lids onto the ground or other contaminated surfaces

if the sample cannot be collected straight into the sample jar / bag, the container it is collected in (such as a bucket or other form of sampler) will be thoroughly rinsed with ambient site water to ensure is not contaminated

samples will be placed in an esky and will be kept under the appropriate holding conditions for each parameter until delivered to the laboratory within the appropriate holding time (as advised by the analytical laboratory), in accordance with the security and transport protocols outlined in the Monitoring and Sampling Manual (DERM 2009)

a chain of custody form will be completed for all samples sent to the laboratory for analysis, and

samples will be analysed by a NATA-accredited laboratory, and laboratory duplicates and blanks will be analysed in accordance with NATA-accredited protocols.

5.8 Aquatic Habitat

In order to assist with the interpretation of results, habitat at each site will be described using datasheets based on the AUSRIVAS protocols (DNRM 2001) and State of the Rivers protocols (Anderson 1993b). Site information will be collected from each site based on AUSRIVAS protocols including:

stream order

distance from source

bank full height and width

stream width

rain history of the site and where possible the water level history of the site

the proportion of each habitat type in the reach

the water depth and velocity

the width and cover of the riparian zone

shading

point source pollution

non point source pollution

the presence and distance to barriers and the type of barrier

adjacent land use

description of substrate, and

the percent coverage and type of aquatic vegetation.




Each site will also be given a habitat assessment score using the River Bioassessment Program datasheet (DNRM 2001). Visual conditions at each site at the time of sampling will be recorded using photographs.

Table 19 Aquatic Habitat Monitoring Program

Sampling Site Sampling Method Sampling Frequency

Aquatic Habitat Receiving Environment Sites:

5 sites downstream

Control Sites:

4 sites upstream

Data sheets based on AUSRIVAS and State of the Rivers protocols


5.9 Field Observations

Visual conditions at the time of sampling will be recorded at each site using photographs. In conjunction with photographs field observations will also be recorded, to provide an ‘early warning’ of potential adverse impacts. This might include looking for evidence of the following (for example):

unusual deposits of sediment

signs of chemical precipitation

signs of bed or bank instability (i.e. sediment build up or erosion)

odours

water colour or clarity (such as greenish, muddy, pale brown and cloudy)

heavy algal or plant growths

surface scum

dead or dying fauna (i.e. fish) or flora (i.e. vegetation in waterways or on banks)

nearby earthworks or construction activity, and

wind speed and direction.

5.10 Monitoring of Unplanned Releases to the Watercourse

Various monitoring programs which occur at the Spring Gully WTF during normal operations areoutlined below.

Water Quality Monitoring Program (WQMP) (CDN: 8600569) – which involved the initial characterisation study (report Q-8200-95-TR-0006 Spring Gully CSG Water Characterisation Study submitted to the Office of the Water Supply Regulator (OWSR) 01/04/11) and current ongoing monitoring of the quality of treated CSG water being discharged from Spring Gully WTF.

Operations staff daily monitoring of process and environmental parameters – which involves on-site water quality analysis of the treated CSG water for multiple parameters.

This REMP – which details the surface water quality and aquatic ecology monitoring for Eurombah Creek to monitor the environmental health of the creek within the defined receiving environment.

Plant control system at the Spring Gully Water Treatment Facility – which provides real-time monitoring and control of the treatment process at Spring Gully WTF as described in Section 2.2 of Report Q-8200-95-TR-0006 Spring Gully CSG Water Characterisation Study (submitted to OWSR, 01/04/11). Data from the control system is recorded and retained as part of WTF records

Routine pond inspections by operations staff at the Spring Gully WTF in accordance with the LNG Dams Inspection Schedule (CND: 8333963). The observations involve recording:

An annual inspection and report is conducted by a Registered Professional Engineer Queensland (RPEQ) for each of the regulated dams to assess the condition and adequacy of each pond against the necessary structural, geotechnical and hydraulic performance criteria.

These programs are deemed appropriate to measure and monitor minor unplanned releases to watercourse, such as minor quality exceedances which may occur in relation to the discharge of treated CSG water to Eurombah Creek. The monitoring of more significant unplanned releases to watercourse is described below.




The extent of additional monitoring in the receiving environment will be determined based on the nature, severity and duration of the unplanned release event. Severe weather conditions such as flooding could be a potential cause of an unplanned release, particularly from ponds and due consideration of safety and accessibility of Eurombah Creek and surrounding area will be considered whilst scheduling additional monitoring.

5.11 Data Analysis

5.11.1 Aquatic Macroinvertebrates and Zooplankton

Permutational multivariate analysis of variance (PERMANOVA) will be used to determine if there aredifferences in the community composition of aquatic macroinvertebrates and zooplankton between control and receiving environment sites over time. PERMANOVA is comparable to multivariate analysis of variance (MANOVA); however, rather than using F-tables to derive statistical significance, PERMANOVA uses permutational methods, which require fewer assumptions to be met (Anderson et al. 2008). PERMANOVA can be used to examine single variables, similar to analysis of variance (ANOVA) but without the restrictive assumptions that ANOVA has (Anderson et al. 2008).

To determine whether there is a difference in the community composition between sites over time (survey periods), analyses will be conducted using a three factor PERMANOVA with the following factors:

Survey

Location (control and receiving environment), and

Site (nested in location).

In the analysis, location and survey are fixed factors and site (nested in location) is a random factor. Data will be fourth root transformed to reduce the influence of very abundant taxa, and give more weight to the less abundant (mid-range) taxa. Data will then be converted to a Bray Curtis similarity matrix and tested for significance using 9999 permutations, where possible. Differences in the composition of aquatic macroinvertebrate communities between sites, over time will be visualised using non-metric multidimensional scaling (nMDS) ordination. Similarity percentages (SIMPER) analysis will determine the key taxonomic groups that contribute to the differences between sites and between surveys.

The mean concentrations of water and sediment quality parameters will be compared with aquatic macroinvertebrate and plankton community structure between control and receiving environment locations (sites grouped within location) for each survey, using the BIOENV routine. Only parameters that show differences in concentrations between sites will be included in the BIOENV analysis.

Abundance, taxonomic richness, Plecoptera / Ephemeroptera / Trichoptera (PET) richness and stream invertebrate grade number – average level (SIGNAL) scores will also be calculated for each sampleand are described in Appendix C. These indices will be compared between the control environment location and the receiving environment location, between sites, and between surveys, using separate univariate PERMANOVAs.

Results from the REMP will be interpreted by persons with expert knowledge. Based on these assessments the REMP will be regularly reviewed and amended as necessary. Monitoring data collected as part of the REMP will be appropriately recorded, maintained and made available to DEHPupon request.

5.11.2 Surface Water Quality

Summary statistics, including the mean, median, minimum and maximum values and the 95th

percentile, will be compiled and tabulated for each water quality parameter based on data pooled across all REMP surveys. As the surface water quality results from REMP surveys to date were consistent between sites upstream of the discharge and between sites downstream of the discharge, data will be pooled depending on whether they were from the control sites (upstream) or the receiving environment sites (downstream), and medians will be calculated and compared with the WQOs identified in Section 4. As per the ANZECC & ARMCANZ (2000) guidelines, the median values at receiving environment sites will be compared to the:

Background data (i.e. mean data from the control sites)

WQOs identified in Section 4.

In accordance with the methods outlined in the national guidelines (ANZECC & ARMCANZ 2000), the 95th percentile of data for the control and receiving environment sites for toxicants (i.e. ammonia, nitrate, metals and metalloids, total petroleum hydrocarbons and fluoride) will be compared with the WQOs identified in Section 4.




For results that show a significant spatial pattern between control and receiving environment sites, the mean and standard error (SE) will be graphed and compared between sites and between surveys, and to the WQOs. For results below the laboratory limit of reporting, the value of the limit of reporting will behalved for graphical purposes, as recommended in the Australian Guidelines for Water Quality Monitoring and Reporting (ANZECC & ARMCANZ 2000b). Where required, graphs will be presented using a logarithmic scale so that the range of concentrations recorded is clearly visible on the graph.

5.11.3 Stream Sediment Quality

Summary statistics, including the mean, median, minimum, maximum and 95th percentile values, will be compiled and tabulated for each sediment parameter, based on data pooled across surveys. Where relevant, the 95th percentiles will be compared to the sediment quality guidelines defined in the CSIRO (2010) guidelines.

Graphs will be produced for each parameter of interest to enable a comparison of stream sediment at control sites (upstream of the discharge) to stream sediment at receiving environment sites (downstream of the discharge), and a comparison of stream sediment quality across all surveys. Only results above the laboratory limit of reporting, or that show a significant spatial pattern between control and receiving sites, will be presented.

5.11.4 White-throated Snapping Turtle

The number of White-throated Snapping Turtles observed at each REMP site within the two hour observation period will be plotted on a bar chart or summarised in a table. Demographic information (i.e. size and sex) may be presented as proportions of the overall number of individuals sighted,depending on the quantity of data collected. Qualitative statements may be made regarding any evidence of White-throated Snapping Turtle breeding (e.g. observation of hatchlings). Details of nests encountered during the surveys will be summarised in a table.

6. References

1. EPA, 2005, Guideline: Establishing Draft Environmental Values and Water Quality Objectives, Environmental Protection Agency, Brisbane.

2. DERM, 2009, Monitoring and Sampling Manual 2009, Environmental Protection (Water) Policy 2009, Version 1, Department of Environment and Resource Management.

3. DEHP, 2009. Queensland Water Quality Guidelines Version 3 September 2009. Department of Environment and Heritage Protection, Brisbane

4. ANZECC & ARMCANZ, 2000, Australian and New Zealand Guidelines for Fresh and Marine Water Quality, National Water Quality Management Strategy, Australian and New Zealand Environment and Conservation Council & Agriculture and Resource Management Council of Australia and New Zealand.

5. Joo, M., Yu, B., Carroll C., Fentie, B. (2005) Estimating and modelling suspended sediment loads using rating curves in the Fitzroy River catchment Australia. International Congress on Modelling and Simulation. Modelling and Simulation Society of Australia and New Zealand.

6. Simpson, S.L., Batley, G.E., Chariton, A.A., Stauber, J.L., King, C.K., Chapman, J.C., Hyne, R.V., Gale, S.A., Roach, A.C. & Maher, W.A., 2005, Handbook for Sediment Quality Assessment, CSIRO, Lucas Heights, NSW.

7. DEHP 2011. Environmental Protection (Water) Policy 2009 Dawson River Sub-basin Environmental Values and Water Quality Objectives Basin No. 130 (part), including all waters of the Dawson River Sub-basin except the Callide Creek Catchment. Department of Environmental and Heritage Protection, September 2011.

8. Dunlop, J.E., Mann R.M., Hobbs, D., Smith R.E.W., Nanjappa, V., Vardy S. and Vink, S. 2016. ‘Considering background ionic proportions in the development of sulfate guidelines for the Fitzroy River Basin’. Australasian Bulletin of Ecotoxicology and Environmental Chemistry, 3: 1-10.

9. Halcrow Pacific Pty Limited, 2012, Dawson River Release Scheme Direct Toxicity Assessment prepared for Santos GLNG Project, Halcrow Pacific Pty Limited, 13 November 2012

10. Acqua Della Vita Pty Ltd, 2013, Condamine River DTA of boron and treated CSG water, prepared by Heather Chapman, 28 November 2013




11. Acqua Della Vita Pty Ltd, 2016, Evaluation of boron protective concentrations for the Condamine and Dawson River release schemes and applicability to the Spring Gully CSG Water Management Scheme, prepared by Dr Heather Chapman, 13 November 2016

12. Boobook, 2017, Fauna Survey Report – survey for White-throated Snapping Turtle (Elseya albagula) at Eurombah Creek, Spring Gully Gas Field. Prepared by Boobook Ecological Consulting for Origin, 2 June 2017.

13. Eyre T.J., Ferguson D.J., Hourigan C.L., Smith G.C., Mathieson M.T., Kelly A.L., Venz M.F., Hogan L.D., and Rowland J. 2014. Terrestrial Vertebrate Fauna Survey Guidelines for Queensland, version 2.0. Department of Science, Information Technology, Innovation and the Arts, Queensland Government, Brisbane.

14. Thomson S, Georges A and Limpus CJ, 2006, A new species of freshwater turtle in the Genus Elseya (Testudines: Chelidae) from Central Coastal Queensland, Australia. Chelonian Conservation and Biology 5: 74-86.

15. Hamann M, Schäuble CS, Limpus DJ, Emerick SP and Limpus CJ, 2007, Management plan for the conservation of Elseya sp. [Burnett River] in the Burnett River Catchment. Report prepared by the Queensland Environmental Protection Agency.






Title Name/s

IG-Operations-APLNG-HSE Stuart Fletcher, Adrian Woehrle

DOCUMENT HISTORY

Rev Date Changes made in document Reviewer/s Consolidator Approver

0 20/04/2011 Issued for use JRM DC SM

1 24/06/2011 Updated: Table 2 formatting error corrected, addition of section 6.11 – Deviation of Surface Water Quality Background Values. Information regarding unplanned release to watercourse removed and provided under separate cover

JRM DC SM

2 22/03/2013 Amended to address recommendations DEHP and the annual report

FRC

Environmental

JRM JL

3 08/08/2014 Amended to address recommendations from the REMP 2013 Annual Report.

MCR KP JL

4 24/02/2017 Amended to include site specific WQOs, SGSW7 and address recommendations in the 2014-2016 annual reports and NRA review dated 13/7/15

NRA

Veronica Cavanough

Veronica Cavanough

Stuart Fetcher

5 21/11/2017 White-Throated Snapping Turtle monitoring inclusion

NRA

Veronica Cavanough

Veronica Cavanough

Adrian Woehrle




Appendix A Photos

Figure 5 Eurombah Creek spate Figure 6 Eastern Gully: inflowing treated CSG water

Figure 7 Treated CSG water outlet: Eastern Gully Figure 8 Flow & riffle ecosystem in Eastern Gully

Figure 9 Cattle damage & poor riparian zone Figure 10 Discharge created connection downstream pools




Figure 11 Upstream pool: start of dry season Figure 12 Same pool: shrinkage a few months later

Figure 13 Upstream pool: start of dry season Figure 14 Same pool: dry




Appendix B Summary of REMP Control Sites Surface Water Quality Results from August 2011 to 2015 (NRA, 2016)













Appendix C Introduction to the Proposed Data Analysis

C.1. Aquatic Macroinvertebrate Indices

A number of indices are effective indicators of ecosystem health (EHMP 2004). Use of multiple indices contributes to the robustness and reliability of any assessment. The following indices have all been found to be effective indicators of ecological health (EHMP 2004) and will be used as indicators in the REMP.

C.2. Taxonomic Richness

Taxonomic richness is the number of taxa (typically families) in a sample. Taxonomic richness is the most basic and unambiguous diversity measure, and is considered to be among the most effective diversity measures. It is however, affected by arbitrary choice of sample size. Where all samples are considered to be of equal size, taxonomic richness is considered to be a useful tool when used in conjunction with other indices. Richness does not take into account the relative abundance of each taxa, so rare taxa have as much ‘weight’ as common ones.

C.3. PET Richness

While some groups of aquatic macroinvertebrates are tolerant of pollution and environmental degradation, others are sensitive to these stressors (Chessman 2003). The Plecoptera (stoneflies), Ephemoptera (mayflies), and Trichoptera (caddisflies) are referred to as PET taxa, and they are particularly sensitive to disturbance. There are typically more PET families in sites with good habitat and water quality than in degraded sites, and PET taxa are often the first to disappear when water quality or environmental degradation occurs (EHMP 2007). The lower the PET score, the greater the inferred degradation.

C.4. SIGNAL 2 Scores

SIGNAL (Stream Invertebrate Grade Number — Average Level) scores are also based on the sensitivity of each aquatic macroinvertebrate family to pollution or habitat degradation. The SIGNAL system has been under continual development for over 10 years, with the current version known as SIGNAL 2. Each aquatic macroinvertebrate family has been assigned a grade number between 1 and 10 based on their sensitivity to various pollutants. A low number means that the aquatic macroinvertebrate is tolerant of a range of environmental conditions, including common forms of water pollution (e.g. suspended sediments and nutrient enrichment).

SIGNAL 2 scores are an index of aquatic macroinvertebrate communities that gives an indication of the types of pollutants and other physical and chemical factors affecting a site, that is also weighted for abundance, so that the relative abundance of tolerant or sensitive taxa can be taken into account (instead of only the presence / absence of these taxa). The overall SIGNAL 2 score for a site is based on the total of the SIGNAL grade (multiplied by the weight factor) for each taxa present at the site, divided by the total of the weight factors for each taxa at the site.

Low SIGNAL 2 scores indicate low abundance of moderately sensitive taxa and a high abundance of tolerant taxa, which in turn is indicative of poor habitat quality. In contrast, a high SIGNAL 2 score indicates moderate to high abundance of sensitive taxa, which is indicative of good habitat quality (Chessman 2003).

C.5. Multivariate Analyses

Multivariate statistical techniques are widely used in ecology to assess the similarities / relationships between communities. Whereas univariate analyses can only compare one variable at a time (e.g. an index of community structure such as a diversity index, or a single indicator species), multivariate analyses can compare samples based on the extent that communities share particular taxa and the relative abundances of each taxa (Clarke & Warwick 2001).

Ordinations are particularly useful tools for analysing, and visually presenting, differences among communities. Ordinations are maps of samples, in which the placement of samples on the map reflects the similarly of the community to the communities in other samples (Clarke & Warwick 2001). Distances between samples on an ordination attempt to match the similarities in community structure:




nearby points represent communities with very few differences; points far apart have very few attributes in common (Clarke & Warwick 2001).

The first step of multivariate analysis usually involves the creation of a similarity or dissimilarity matrix, which incorporates the creation of a triangular matrix of similarity coefficients, computed between every pair of samples. The coefficient is usually a measure of how close the abundance levels are for each species (defined so that 100% = total similarity and 0% = complete dissimilarity). While there are a number of metrics used, the Bray-Curtis coefficient is commonly to convert biological data (i.e. abundances of different taxonomic groups) into a similarity matrix (Clarke & Warwick 2001).

C.6. Non-Metric Multi-dimensional Scaling (nMDS)

Non-metric multi-dimensional scaling (nMDS) attempts to place samples on a ‘map’, such that the rank order of the distances among samples matches the rank order of the matching similarities from the similarity matrix (Clarke & Warwick 2001). This provides a visual representation of the similarities among communities within each sample. Note that each of the axes is not related to any particular value; in fact axes can be rotated to provide the best visual representation of the data.

A stress coefficient is calculated to reflect the extent to which the nMDS ordination and the similarity matrix agree (Clarke & Warwick 2001) (i.e. how well the nMDS ordination accurately reflects the relationship between samples). Stress values of <0.15 are generally acceptable for interpretation.

C.7. Analysis of Similarities (ANOSIM)

ANOSIM is analogous to analysis of variance (ANOVA) in univariate statistics (Clarke 1993; Smith 2003). A global R statistic is calculated to determine whether there is a significant difference among all samples. If there are differences, then pairwise comparisons are conducted to test for differences between pairs of samples (analogous to post-hoc tests in ANOVA).

The ‘R’ value lies between +1 (all similarities within groups are less than any similarity between groups) and -1 (similarities among groups are less than within groups), with a value of zero representing the null hypothesis (no difference among a set of samples) (Clarke & Warwick 2001). Comparison of pair-wise R values can give an indication of how different communities are: R values close to 0 indicate little difference, values around 0.5 indicate some overlap and values close to 1 to indicate many or substantial differences. In many instances however, researches are primarily interested in whether the R value is statistically different from zero (usually at a confidence level of 0.05) (Clarke & Warwick 2001), i.e. whether they can reject the null hypothesis.

ANOSIM can provide information on whether the (visual) differences between assemblages in the nMDS ordination are significantly different based on an independent permutation test that is separate from the nMDS ordination. It is based on testing the differences between the rank similarities in the similarity matrix, not on the distances between samples in the nMDS ordination (Clarke & Warwick 2001).

C.8. Similarity Percentage – Species Contributions (SIMPER)

SIMPER analysis was done to identify the species / taxa that contributed to the dissimilarity between the communities at each site (i.e. it identifies which species are contributing the most to the differences among and within sites). SIMPER analysis may help to identify potential ‘indicator’ species. For example, if a particular species consistently contributes substantially to the differences between impacted and un-impacted assemblages, it may be a useful indicator of environmental harm. The abundance of this indicator species can then be compared among sites using univariate techniques such as ANOVA.

C.9. BIOENV

The BIOENV procedure is part of the RELATE function in the PRIMER 6 software, and can be used to examine the extent to which observed community patterns in biological data, such as the composition and abundance of aquatic macroinvertebrates among different sites, can be related to a combination of observed physical or chemical variables collected from the same sites (Clarke & Warwick 2001). The combinations of physical or chemical variables are compared against biological variables, using increasing levels of complexity. The combination of environmental variables that best describe the biological community pattern are ranked and analysed using a rank correlation coefficient test (Spearman’s coefficient – Rho ()). Values of lie between -1 and 1, which corresponds to cases that are in complete opposition or in complete agreement, -values around zero occur when there is no




match between the two patterns (Clarke & Warwick 2001). The combination of environmental variables that best describes any biological pattern will typically be closer to 1 than 0.

Scaling or normalisation of environmental data is usually required, so that each of the variables have comparable, dimensionless scales (Clarke & Warwick 2001). This helps to eliminate differences that may be caused by arbitrary scaling of the variable (e.g. the results will be different using mg/kg or µg/kg for stream sediment metal concentrations).

C.10. PERMANOVA, PCO and DSTLM

PERMANOVA is used to test simultaneous responses of one or more variables to one or more factors in an ANOVA design, using permutation methods (Anderson 2004). PERMANOVA generates an F-statistic similar to traditional ANOVAs, but p-values are calculated with permutations, which assume normality. PERMANOVA can provide information on whether the (visual) differences between communities in the multi-dimensional scaling ordination (e.g. PCO) are significant; it is an independent test from the multi-dimensional scaling ordination.

To determine whether the development has a significant impact on the receiving environment, the changes in the community composition among sites over time (surveys) will be conducted using a three factor PEMANOVA with the following factors:

treatment (upstream and downstream)

site (nested in treatment), and

survey.

Where significant differences are found between sites, a post-hoc pairwise comparison to test for differences between pairs of samples (analogous to post-hoc tests in ANOVA) will be conducted.

The level of dispersion among sites within each of the test groups will be examined using the permutational analysis of multivariate dispersions (PERMDISP) routine. In traditional impact assessment, a change in the dispersion of data can indicate an impact (Anderson 2004). The PERMDISP will examine the amount of dispersion.

DISTLM analysis will also be done to investigate linear correlations between a multivariate data set (e.g. aquatic macroinvertebrate communities) and factors such as distance downstream of the discharge and the concentration of key water quality parameters.

C.11. References

Anderson, M.J., 2004. PERMDISP: a FORTRAN computer program for permutational analysis of multivariate dispersions (for any two-factor ANOVA design) using permutation tests. Department of Statistics, University of Auckland, New Zealand.

ANZECC & ARMCANZ, 2000, Australian and New Zealand Guidelines for Fresh and Marine Water Quality, National Water Quality Management Strategy, Australian and New Zealand Environment and Conservation Council & Agriculture and Resource Management Council of Australia and New Zealand.

Chessman, B., 2003. Signal 2 A Scoring System for Macro-Invertebrates ('water-bugs') in Australian Rivers. Monitoring River Health Initiative Technical Report Number 31. Commonwealth of Australia, Canberra.

Clarke, K.R., 1993, 'Non-parametric multivariate analyses of changes in community structure', Australian Journal of Ecology 18: 117-143.

Clarke, K.R. & Warwick, R.M., 2001, Change in Marine Communities: an Approach to Statistical Analysis and Interpretation, PRIMER-E, Plymouth.

DERM, 2009. Queensland Water Quality Guidlines Version 3 September 2009. Department of Environment and Resource Management, Brisbane

EHMP, 2004. Ecosystem Health Monitoring Program 2002-2003, Annual Techniqual Report. Moreton Bay Waterways and Catchment Partnership, Brisbane.

EHMP, 2007. Ecosystem Health Monitoring Program 2005-2006, Annual Technical Report. South East Queensland Healthy Waterways Partnership, Brisbane.

Smith, K.A., 2003, 'A simple multivariate technique to improve the design of a sampling strategy for age-based fishery monitoring', Fisheries Research 64: 79-85.

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