Australia Pacific LNG

Transcription

1 Spring Gully North-West and North-East Project Preliminary Documentation Q RP-1399 Australia Pacific LNG Preliminary documentation for the Spring Gully North-West and North-East Project. Revision Date Description Originator Checked QA/Eng Approved 1 8/12/2017 Issued for Use A. Skelly 0 23/8/2017 Issued for Use A. Skelly V. Cavanough T. Smith R. Morris V. Cavanough C. Gamage L. Helm J. Schortinghuis S. Dale S. Dale S. Dale S. Dale

2 Release Notice This document is available through the Australia Pacific LNG Upstream Project controlled document system TeamBinder. 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. Third-party issue can be requested via the Australia Pacific Upstream Project Document Control Group. 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 Communities and Access Environmental Approvals Manager. 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 Communities and Access Environmental Approvals Manager. Doc Ref: Q RP-1399 Revision: 1 Page 2

3 Table of Contents 1. Introduction Proposed Action and Location Proponent and Environmental History Regulatory Assessment Process Purpose of this Report Terms and Abbreviations Project Description Overview Project Footprint Operation and Timing Field Planning Wells Well Design and Construction Drilling Muds, Cement and Completion/Workover Fluids Gas and Water Gathering Flowlines Supporting Infrastructure Landspray While Drilling Trial Details and Outcomes EA Conditions LWD Operations Changes to Project Description CSG Water and Brine Management CSG Water Production Profile CSG Water Quality CSG Water Management Strategy Water Balance Model CSG Water Treatment Brine Ponds CSG Water Use Project Activities Irrigation and Stock Watering Injection Flow-Paced Biological Control Disinfection Doc Ref: Q RP-1399 Revision: 1 Page 3

4 Cartridge Filtration Degasification Oxygen Scavenger and Corrosion Inhibitor Injectate Monitoring Brine Management Social and Economic Matters Listed Threatened Species and Communities White-throated Snapping Turtle Introduction Suitably Qualified Experts Survey Area Species Ecology and Distribution in Relation to the Survey Area Methodology Desktop Assessments Field Assessments Results and Discussion Survey Conditions Survey Site Characteristics Presence of White-throated Snapping Turtle White-throated Snapping Turtle Habitat Potential Impacts Terrestrial Threatened Species and Ecological Community Survey Effort Fauna Surveys Ecology Surveys Pre-clearance Surveys Habitat Mapping Brigalow TEC MNES Flora and Fauna Potential Impacts Significant Impact Assessment Management Measures Groundwater Introduction Hydrogeological Conceptualisation Doc Ref: Q RP-1399 Revision: 1 Page 4

5 6.3. Groundwater Levels Groundwater Quality Third party Groundwater Users Groundwater Dependent Ecosystems Groundwater Modelling Potential Hydrological Impacts of the Project Scenario A Scenario B Significant Impact Assessment Potential Groundwater Quality Impacts Construction, Operation and Decommissioning of CSG Wells Production Injection Significant Impact Assessment Cumulative Impacts Management Measures Surface Water Existing Environment Potential Impacts and Management Measures CSG Water Management Landspray While Drilling Avoidance, Safeguards and Mitigation Measures Environmental Offsets Environmental Outcomes Conclusions Ecologically Sustainable Development Consideration of Project Compliance with the Principles of ESD References Doc Ref: Q RP-1399 Revision: 1 Page 5

6 List of Appendices Appendix 1: Maps Appendix 2: Cross Reference with Request for Information Appendix 3: Cross Reference with the IESC Advice Appendix 4: Spring Gully Environmental Authority Appendix 5: List of Persons Appendix 6: IESC Checklist Appendix 7: Spring Gully Environmental Constraints Planning and Field Development Protocol (Q MP-1157) Appendix 8: Landspraying While Drilling Trial Interpretative Report and Recommendations (URS, 2014) Appendix 9: Landspraying While Drilling Procedure (Q-LNG01-35-AP-0048) Appendix 10: Spring Gully Coal Seam Gas Water Management Plan (Spring Gully CWMP) (CDN/ID ) Appendix 11: Spring Gully Aquifer Injection Management Plan Precipice Sandstone (CDN/ID ) Appendix 12: Survey for White-Throated Snapping Turtle (Elseya albagula) at Eurombah Creek, Spring Gully Gas Field (Boobook, 2017) Appendix 13: Refinement of Spring Gully North-West and North-East Development Areas MNES Habitat Mapping (Boobook, 2017) Appendix 14: Spring Gully Development EPBC Referral IESC Advice Response North West and North East Development Areas (KCB, 2017) Appendix 15: Threatened Species and Ecological Community Management Plan (Q MP- 1158) Appendix 16: Groundwater Monitoring Plan (Q-LNG MP-0005) Appendix 17: Spring Gully North-West and North-East Drilling Mud and Cement Additive Chemical Risk Assessment (ERM, 2017) Appendix 18: Spring Gully (North-West and North-East Development) Environmental Offset Package Report (AMEC, 2017) Doc Ref: Q RP-1399 Revision: 1 Page 6

7 List of Tables Table 1: Terms Table 2: Abbreviations Table 3: Untreated CSG Water Quality Table 4: Treated CSG Water Quality Table 5: CSG Water Use Approvals Table 6: Refinement of Habitat Mapping Table 7: Potential Impacts to Threatened Flora and Fauna Table 8: Assessment of Impacts to Terrestrial Threatened Species Table 9: Management Practices for Threatened Species and Ecological Communities Table 10: Constraints Category Table 11: Summary of Hutton Sandstone, Bandanna Formation and Precipice Sandstone Water Quality78 Table 12: Springs within Proximity to the Project Area Table 13: Significant Impact Criteria (Section 5.3 Changes to Hydrological Characteristics) Groundwater Table 14: Summary of Risks Table 15: Significant Impact Criteria (Section 5.4 Changes to Water Quality) Groundwater Table 16: Predicted Cumulative Impact Assessment Groundwater Bores Table 17: Predicted Cumulative Impact Assessment - Springs Table 18: Environmental Outcomes List of Figures Figure 1: Typical Construction RoW Layout Figure 2: Summit Earth Navigator System Figure 3: LWD Spray Field Example Figure 4: CSG Water Production for the Project Figure 5: CSG Water Treatment Simplified Process Flow Diagram Figure 6: PRP Process Flow Diagram Figure 7: Brine and Salt Production Figure 8: Regional Hydrostratigraphy (sourced from OGIA, 2016a) Figure 9: Geological Cross Section through NEDA and NWDA (Data source OGIA Geological Model, 2016a) Figure 10: Schematic Stratigraphy with Associated Physicochemical Parameters Figure 11: Precipice Sandstone Groundwater Users (KCB, 2017) Doc Ref: Q RP-1399 Revision: 1 Page 7

8 Figure 12: Location of Springs within Proximity to the Project (KCB, 2017) Figure 13: Scenario A Head Change at Precipice Sandstone Groundwater Bore Receptors Figure 14: Scenario A - Head Change at Precipice Sandstone Sourced Springs Figure 15: Scenario A - Head Change at Hutton Sandstone Sourced Springs Figure 16: Scenario A - Head Change at Boxvale Sanstone Member Sourced Springs Figure 17: Scenario B - Head Change at Precipice Sandstone Groundwater Bore Receptors Figure 18: Scenario B - Head Change at Precipice Sandstone Sourced Springs Figure 19: Scenario B - Head Change at Hutton Sandstone Sourced Springs Figure 20: Scenario B - Head Change at Boxvale Member Sourced Springs Figure 21: Groundwater Exceedance Response Process Doc Ref: Q RP-1399 Revision: 1 Page 8

9 1. Introduction 1.1. Proposed Action and Location In 2004, the Spring Gully coal seam gas (CSG) Project was referred to the Minister pursuant to the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) (EPBC 2004/1644 and 2004/1924) and subsequently determined not to be a controlled action. The Spring Gully CSG Project, located on petroleum leases (PL) 195, 200, 203, 204 and 268 (currently in application to replace PL203), commenced CSG production during 2005 and supplies the domestic market and the Australia Pacific LNG Pty Limited (Australia Pacific LNG) liquefied natural gas (LNG) plant at Gladstone for export. More recently, and as contemplated by the 2004 referrals, the Spring Gully CSG Project incorporated a number of adjoining petroleum tenures. Limited development has occurred within these adjoining tenures to date. Origin Energy Upstream Operator Pty Ltd (Origin Energy), on behalf of Australia Pacific LNG now propose to develop CSG resources located in: PL 414, 415, 416 and part of 418, known as the Spring Gully North-West Development Area (NWDA). PL 417, known as the North-East Development Area (NEDA). The Spring Gully North-West and North-East Development (referred to as the Project ) will involve approximately 114 wells and associated gathering infrastructure within the NWDA and NEDA (Appendix 1 Figure 1), which will connect into the operating gas processing facilities (GPF) and water treatment facility (WTF) located on PLs 195 and 204, which form part of the existing Spring Gully CSG Project. The Project is located approximately 70km north-east of Roma in southern central Queensland. The following terms are used in this report to describe spatial extents: Development footprint area which will be disturbed by the Project. Comprises approximately 601ha. NWDA approximately 16,289ha (total area of the PLs). NEDA approximately 23,135ha (total area of PL417). Project area approximately 39,424ha encompassing NWDA and NEDA. Spring Gully CSG Project the existing Spring Gully development located on PLs 195, 200, 203, 204 and 268 (currently in application to replace PL203). Spring Gully Regional Area (SGRA) - describes the area encompassed by PLs 195, 200, 203, , 414 to 419 and Authority to Prospect (ATP) Proponent and Environmental History Australia Pacific LNG is committed to responsible environmental management. Origin Energy (upstream operator for Australia Pacific LNG) has a Health, Safety and Environmental Management System which helps govern all activities and ensures continual improvement in managing environmental risks. Origin sets objectives and targets that promote the efficient use of resources, minimisation of wastes and emissions and the prevention of pollution. Origin Energy aims to comply with all environmental regulations and conditions attached to approvals to operate, and promptly report any non-compliance to relevant authorities. Employees and contractors to Origin Energy are encouraged to report on environmental performance associated with activities. To Doc Ref: Q RP-1399 Revision: 1 Page 9

10 increase an understanding and improve in a company-wide performance, a register of all environmental incidents, observations and good practices is maintained. Australia Pacific LNG and Origin Energy have not been subject to court proceedings under a Commonwealth, State or Territory law for the protection of the environment or the conservation and sustainable use of natural resources. As the upstream operator for Australia Pacific LNG, Origin Energy is committed to protecting the environment and consequently manages Health Safety and Environment (HSE) matters as critical business activities. Origin Energy has developed corporate environmental policies that provide a public statement of the corporate commitment to protecting the environment during operations. In addition, Origin Energy, as an operator of gas production activities, uses a structured approach to the management of HSE issues through a documented HSE Management System. This management system ensures that environmental risks associated with Origin s operations are either avoided or kept to as low as reasonably practicable. In addition the HSE Management System drives continuous improvement in the company s environmental performance and assists in providing confidence to regulators, commercial partners and stakeholders that Origin is managing its operations in an environmentally responsible way Regulatory Assessment Process The Project is currently authorised under the Queensland Environmental Protection Act 1994 Qld (EP Act) by the Spring Gully Environmental Authority (EA) (EPPG ) (refer to Appendix 4). An EA amendment application was submitted to the State administering authority in August 2012 to include PL417 in the EA. The amendment did not trigger the requirement for an environmental impact statement (EIS) or public notification and the amendment to the EA was approved in October Another EA amendment application was submitted to the administering authority in March 2013 to include PLs 414, 415, 416 and 418 in the EA. The amendment did not trigger the requirement for an EIS or public notification and the amendment to the EA was approved in May The need for amendments to the EA may arise as the Project progresses and may include amendments to ensure compliance with spatial rules for siting infrastructure defined in the EA. The Project (EPBC 2017/7881) was referred to the Minister for the Department of Environment and Energy (DoEE) in February 2017, deemed a controlled action on 6 April 2017 and requires assessment and approval under the EPBC Act. The controlling provisions are: Sections 18 and 18A: Listed threatened species and communities. Sections 24D and 24E: A water resource, in relation to coal seam gas development and large coal mining development. The Project will be assessed by preliminary documentation Purpose of this Report The purpose of this report is to provide additional information as requested by the Department and the Independent Expert Scientific Committee (IESC). On 13 April 2017, the Department issued a request for further information in order to assess the relevant impacts of the proposed action. This Preliminary Documentation was prepared in order to address this request and provided to the Department on the 24 August The Project subsequently was referred to the IESC for assessment in accordance with Section 505D of the EPBC Act. Advice was received from the IESC on 20 October 2017 which has been addressed in this revised Preliminary Documentation. Doc Ref: Q RP-1399 Revision: 1 Page 10

11 A cross reference table to both the additional information requested by the Department and a response to the IESC advice is provided in Appendix 2 and Appendix 3 respectively. The preliminary documentation is comprised of the following: This report Appendix 1: Maps Appendix 2: Cross Reference with Request for Information Appendix 3: Cross Reference with the IESC Advice Appendix 4: Spring Gully Environmental Authority Appendix 5: List of Persons Appendix 6: IESC Checklist Appendix 7: Spring Gully Environmental Constraints Planning and Field Development Protocol (Q MP-1157) Appendix 8: Landspraying While Drilling Trial Interpretative Report and Recommendations (URS, 2014) Appendix 9: Landspraying While Drilling Procedure (Q-LNG01-35-AP-0048) Appendix 10: Spring Gully Coal Seam Gas Water Management Plan (Spring Gully CWMP) (CDN/ID ) Appendix 11: Spring Gully Aquifer Injection Management Plan Precipice Sandstone (CDN/ID ) Appendix 12: Survey for White-Throated Snapping Turtle (Elseya albagula) at Eurombah Creek, Spring Gully Gas Field (Boobook, 2017) Appendix 13: Refinement of Spring Gully North-West and North-East Development Areas MNES Habitat Mapping (Boobook, 2017) Appendix 14: Spring Gully Development EPBC Referral IESC Advice Response North West and North East Development Areas (KCB, 2017) Appendix 15: Threatened Species and Ecological Community Management Plan (Q MP- 1158) Appendix 16: Groundwater Monitoring Plan (Q-LNG MP-0005) Appendix 17: Spring Gully North-West and North-East Drilling Mud and Cement Additive Chemical Risk Assessment (ERM, 2017) Appendix 18: Spring Gully (North-West and North-East Development) Environmental Offset Package Report (AMEC, 2017) 1.5. Terms and Abbreviations Term Spring Gully CSG Project Definition Table 1: Terms The existing Spring Gully development located on PLs 195, 200, 203, 204 and 268 (currently in application to replace PL203) Project The Spring Gully North-West and North-East Development located in PL 414, 415, 416, 417 and part of 418 Doc Ref: Q RP-1399 Revision: 1 Page 11

12 Term Definition NWDA PL 414, 415, 416 and part of 418 NEDA PL 417 SGRA PLs 195, 200, 203, , 414 to 419 and Authority to Prospect (ATP) 592. Table 2: Abbreviations Abbreviation Description ATP Authority to Prospect Australia Pacific LNG Australia Pacific LNG Pty Limited BUA Beneficial use approval CMA Cumulative Management Area CSG Coal seam gas CWMP Coal Seam Gas Water Management Plan DoEE Department of Environment and Energy DNRM Department of Natural Resources and Mines DSITI Department of Science, Information Technology and Innovation EA Environmental Authority EIS Environmental impact statement EHP Environment and Heritage Protection EP Act Environmental Protection Act 1994 EPBC Act Environment Protection and Biodiversity Conservation Act 1999 ESA Environmentally sensitive areas ESD Ecologically Sustainable Development EV Environmental value FEL Front end loading GAB Great Artesian Basin GH General habitat GIS Geographic information system GPF Gas processing facility HSE Health Safety and Environment HQ High quality KCB Klohn Crippen Berger Ltd LNG Liquefied natural gas LQ Low quality LWD Landspray while drilling MBC Mix bury cover Doc Ref: Q RP-1399 Revision: 1 Page 12

13 Abbreviation MNES MSES NEDA NEPM NWDA OGIA PL PRP QWC RE RO RoW RWF SGRA SIA SPR TEC UWIR WDA WTF Description Matters of national environmental significance Matters of State Environmental Significance North-East Development Area National Environment Protection Measures North-West Development Area Office of Groundwater Impact Assessment Petroleum Lease Permeate Reinjection Plant Queensland Water Commission Regional Ecosystems Reverse osmosis Right of way Regulated Waste Facility Spring Gully Regional Area Social Impact Assessment Source-pathway-receptor Threatened ecological communities Underground Water Impact Report Well disposal area Water treatment facility Doc Ref: Q RP-1399 Revision: 1 Page 13

14 2. Project Description 2.1. Overview The Project will involve the progressive development of CSG infrastructure within the NWDA (PLs 414, 415, 416 and 418 (part)) and NEDA (PL417) and will include the following activities: The drilling, installation, operation and maintenance of CSG production wells. The Project is expected to involve approximately 114 production wells. This includes eight (8) wells and associated infrastructure for which some preparatory works have been undertaken to date (e.g. clearing of lease area, access tracks etc.). These preparatory works are excluded from this referral, but have been considered in the cumulative impacts. Installation, operation and maintenance of gas and water gathering flowlines. Installation, operation and maintenance of associated supporting infrastructure (e.g. access roads, power and communication systems, temporary accommodation camps, laydowns, stockpiles etc.). Decommissioning and rehabilitation of infrastructure and disturbed areas. Management of CSG water produced by the Project. The Project will not require development of gas processing facilities or water treatment infrastructure as gas and CSG water will be directed to existing infrastructure located on PLs 195 and 204 and operated pursuant to approvals for the existing Spring Gully CSG Project Project Footprint The proposed location of wells and flowlines for the Project is presented in Appendix 1 Figure 1 and identifies the eight wells which have had some preparatory works completed. During construction of the Project, it is estimated that approximately 601ha of land (approximately 1.5% of the Project area) will be disturbed for wells, flowlines and associated infrastructure. The majority of this disturbance will take place on previously cleared land generally used for cattle grazing with approximately 271ha of remnant/regrowth vegetation to be impacted on the balance area. Additional disturbance areas may be required for associated infrastructure (e.g. laydowns, drill camps, office etc.) where detailed design is yet to be completed. These will be sited to avoid TEC and listed species habitat where practicable Operation and Timing Petroleum activities are currently scheduled to commence in Q or as soon as relevant approvals are obtained, with gas production likely to commence soon after in Q The Project will operate for approximately 30 years Field Planning The final location of wells, flowlines, access tracks and ancillary infrastructure gives consideration to a range of matters including environmentally sensitive areas (ESAs), threatened ecological communities (TEC), significant vegetation, habitat for listed species, topography, cultural heritage, impact on landholders, engineering constraints and construction costs. Wherever practicable, previously disturbed areas are utilised and gathering network and access tracks are co-located. Selected locations are progressively refined in consultation with landholders and other stakeholders to minimise adverse environmental and landholder impacts whilst balancing cost and constructability. Doc Ref: Q RP-1399 Revision: 1 Page 14

15 A robust internal disturbance approval process ensures the project execution aligns with conditions of approval and management commitments, particularly avoidance of key environmental impacts where there are reasonable and practicable design alternatives. The disturbance approval process occurs over a number of stages (FEL front end loading): FEL 0: Preliminary concept developed (well spacing, number, type) based on reservoir modelling. FEL 1: Conceptual layout of infrastructure developed giving consideration to the results of an ecology assessment, landholder and engineering constraints. FEL 2: Environmental specialists, construction personnel, engineers and landholders undertake site assessment to assess the proposed infrastructure locations and the layout is finalised. FEL 3: Required approvals are obtained. Execute: Detailed design is completed and construction commences. The environmental constraints assessment is based on the following principles: Minimising adverse environmental impacts and enhancing environmental benefits associated with project activities, products or services; conserving and protecting the biodiversity values and water resources in its operational areas. Avoiding direct and indirect adverse impacts on environmental values including Matters of National Environmental Significance (MNES) where practicable. Mitigating and managing direct and indirect adverse impacts to minimise cumulative adverse impacts on environmental values including MNES. Active site remediation and rehabilitation of impacted areas to promote and maintain long term recovery of affected environments including MNES. The wells and flowlines shown in Appendix 1 Figure 1 for the NWDA has been developed through the application of this process. The majority of the infrastructure in the NEDA is preliminary concept only (FEL 0) and will be further refined as it progresses through the stages. The requirement for additional supporting infrastructure in the NEDA will also be identified and sited through this process. Spring Gully Environmental Constraints Planning and Field Development Protocol (Q MP-1157) has been developed to ensure a robust strategy is implemented for the identification of environmental values and measures to avoid and minimise potential adverse impacts to these values, both Commonwealth and State values. The Protocol provides a framework for the following: The methodologies that are to be implemented in conducting desktop assessments and field ecological assessments to determine the likelihood of occurrence of MNES and Matters of State Environmental Significance (MSES). The decision making process for siting CSG infrastructure within the Project area. The roles and responsibilities in infrastructure planning, from ecological assessment to post construction reporting. The process for calculating and tracking adverse environmental impacts. Data collection and maintenance processes. Compliance and corrective actions. Protocol review requirements. The Protocol is provided in Appendix 7 and is discussed further in Section 5.3. Doc Ref: Q RP-1399 Revision: 1 Page 15

16 2.5. Wells Well Design and Construction For the Project, approximately 114 wells vertical and horizontal wells are proposed as the base case. However non-intercept horizontal and standard vertical wells could potentially be used in the future. The Bandanna Formation is the target coal seams. The wells will be designed to comply with all requirements of the Department of Natural Resources and Mines (DNRM) Code of Practice for constructing and abandoning coal seam gas wells and associated bores in Queensland ( Code of Practice ) (DNRM 2017) and Origin s Drilling and Completions Standards (Barriers INT TS-002, Casing & Tubing INT TS-003, Cementing INT TS-004 and Well Integrity INT TS-013). This includes ensuring the well design isolates all discrete permeable zones and prevents cross flow. In particular, the well design focuses on protecting potable aquifers and preventing hydrocarbons escaping to the environment. The Code of Practice relates to well design, installation and operational monitoring requirements. The vertical well is drilled to the total depth through the coal seams (~850m deep on average). The horizontal well is then drilled from a location some distance away (around 1,000m) which is directionally drilled to land above the target coal seam at a near horizontal trajectory, with the well's azimuth aimed at the vertical well. A horizontal lateral is then drilled in one (or more, depending on coal thickness) seams and, using active ranging tools to aim, intersects the vertical well previously drilled. The point of this construction method is to connect more reservoir surface area with the vertical well to improve production, while still maintaining a vertical well to run a pump in to produce water from the coal seam. Both the horizontal and the vertical wells use cemented surface and production casing strings to isolate the overburden formations, including aquifers, from the targeted gas reservoir. Casing is a major structural component of a well. In general casing strings are needed to: Isolate previously drilled rock formations to maintain their stability. Act as a barrier to produced fluids (gas and water) contaminating other permeable zones drilled through. Allow the installation of a wellhead and blowout preventer and provide a safe conduit through which to circulate gas in the event of a well kick. Cement is used in well construction to provide isolation behind the steel casing strings and to support the casing through the life of the well. The impermeable nature of the cement used means that it is effective at isolating permeable zones from each other and the surface. Therefore it is used to prevent aquifer contamination, hydrocarbons leaking to the environment and, in general, any unintended flow of fluid between differently pressured formations. Cement is pumped down the casing strings and back up the outside in a similar fashion to drilling mud but displacement stops when the cement is placed around the casing. The completion phase of the well construction is done after the well has been drilled and cemented to isolate aquifers. A completion rig will move to location and a completion pump with metal tubing is run downhole across the coal seams and used to remove excess water (non-aquifer fluid) from the coal seams, to allow gas to flow back to surface. While the rig is on location and conducting operations, fluids compatible with the coal seams are pumped downhole to keep control of the well and ensure it is overbalanced. To ensure compatibility of fluids, produced water that was previously taken from the coal formations is pumped. The produced fluid is taken back out of the well when the well pump begins to operate. Doc Ref: Q RP-1399 Revision: 1 Page 16

17 During the life of the well, the completion design may be removed and replaced if it breaks or requires a smaller sized pump. The process for the workover is similar to the completion, with coal formation water pumped downhole to control the well and a new pump run in hole to replace the old one. The well will be abandoned in accordance with the DNRM code of practice for abandonment of coal seam gas wells (DNRM, 2017) or later version that is relevant at time of abandonment. During the process, the completion tubing is pulled out of hole to surface, and cement is placed across the inside of the casing, to ensure that a minimum of 2 barriers of cement are in existence between any aquifers and gas producing formations Drilling Muds, Cement and Completion/Workover Fluids Drilling muds are used during the construction of CSG wells for many reasons but primarily: Maintaining primary well control. Cleaning the hole as it is drilled. Maintaining the wellbore integrity as it is drilled. The drilling muds used are water based with products added to provide and maintain the required chemical and rheological properties. As the well is drilled, the drilling mud lifts the rock to surface. The drilled rock is stripped out of the mud at surface with solids control equipment, although some of the drilled material accumulates in the mud. The quantity and make-up of the drilling mud is well specific but is approximately 256m 3 (vertical) to 328m 3 (horizontal) and generally comprised of the following: ~92% water. 7.5% additives (in the form of viscosifiers, acidity control, ph modifier, detergents, weighting agent etc.). ~0.5% lost circulation material. Similar to drilling muds, the cement slurry utilises additives to modify the properties for specific purposes. For example, some additives help to prevent gas from migrating through the cement as it sets. Some additives are pre-blended into the dry cement, while others are added to the cement slurry as it is mixed on the fly. The quantity and make-up of the cement is well specific but ranges from approximately 6m 3 (surface casing) to 23m 3 (for production casing and generally comprised of the following: 60-78% cement % water. 2-10% additives. During completion/workover operations, CSG water will be used to clean out and control the well. Small quantities of biocide will be added to this fluid to control bacterial activity. Other products used for well maintenance include products applied directly to the drill rods and connections (e.g. Threadlock and pipe dope). These products are not mixed into the fluids but are applied in small quantities to threaded connections. As part of the abandonment process, the same fluid products utilised during the completion/workover phase of works, in addition to cement and cement additives used during cementing are used. A full list of additives used in the drilling process including the CAS registry number, quantities and concentrations are detailed in Appendix 17. Doc Ref: Q RP-1399 Revision: 1 Page 17

18 2.6. Gas and Water Gathering Flowlines After separation occurs at the wellhead, the low pressure CSG flows into a network of buried pipelines constructed from high density polyethylene. These interconnect all wells operating in a specific area to form the gas gathering network. The gas flows through several subsystems which direct the gas to the GPF. CSG that is produced within the Project will be processed at one of the existing Spring Gully GPFs on PLs 195 and 204. After separation at the wellhead, the CSG water flows into a similarly buried high density polyethylene pipeline network. This forms the water gathering network which channels the water to the Spring Gully WTF on PL195. Some gas will be entrained in the water flowlines and some water will be present in the gas flowlines. This is managed by high point vents and low point drains which are installed along the right of way (RoW). Construction of the flowlines involves the following activities: Clear and grade of the RoW. Pipe stringing and bending. Pipe welding, non-destructive testing and joint coating. Trenching. Padding. Pipe placement in the trench (lowering in and laying). Backfilling and compaction. Pneumatic or hydrostatic testing. Rehabilitation. The RoW width is dependent on several factors including the number of pipes and topographical constraints. The construction RoW width for the Project ranges from 12m to 32m wide with an average of 18m. For RoWs that also include extra work space, widths may be up to 50m. During operations, the RoW is generally reduced to 8m to allow access along the pipe for maintenance activities. A typical construction RoW layout is provided in Figure 1. For the purposes of the impact assessment, 25m construction RoW width has been assumed. Figure 1: Typical Construction RoW Layout Doc Ref: Q RP-1399 Revision: 1 Page 18

19 2.7. Supporting Infrastructure Dependent on distance, the construction workforce will be accommodated in a combination of temporary workers accommodation camps close to work sites, the existing Spring Gully accommodation facilities and/or within local temporary accommodation in nearby regional townships. The Operational workforce will be housed in the existing Spring Gully workers camp accommodation facilities. Access to wells and associated above-ground facilities will require construction of unsealed access roads, though grading and sealing of some roads may be necessary. Access tracks will predominantly be colocated with the gathering RoW. For standalone access, utilisation and minor upgrades of existing access tracks is preferred. Laydowns, stockpiles, temporary drilling camps, extra work spaces, mobile offices, substation kiosks and telecommunication towers are some of the additional supporting infrastructure that may be required. These will be sited in accordance with Section Landspray While Drilling There are three main options that are used for the disposal of drilling fluids and muds, Landspray while drilling (LWD), trucking to a suitable licensed waste facility or Mix Bury Cover (MBC); or a combination of all three. LWD is the preferred option, depending on the suitability of the land, and acceptance from the landholder. Where the land is not suitable and/or the landholder does not agree, trucking to a licensed facility or MBC will be used. During drilling, the drilling fluids are returned to surface and cuttings are removed via the shaker and then reclyced back into the system to be used again. Once drilling is complete, the drilling fluids which are suitable for LWD are transferred to tanks on the well site. A purpose-built vacuum truck then draws up the drilling fluids and are transported to the nominated location for LWD application. LWD is the spraying of pre-assessed drilling by products at controlled application rates to top soil in vegetated areas. Benefits of the LWD method include: The safer method of waste management as it reduces heavy vehicle movements on public roads by 8-12 round trips per well. Reduction in required civil earthworks to construct a well pad as opposed to the sump/mbc disposal method. It is intended to LWD all wells provided suitable land can be identified and approval from landowners are obtained. Suitable locations of LWD will be determined in consultation with landowners. Typically from wells in the Project area, disposal volumes are approximatley 120m 3. This volume is applied across approximately 4ha of land for a well that is able to utilise the LWD disposal method Trial Details and Outcomes A trial study was undertaken by an independent third party, URS, to validate the Canadian LWD methodologies applicability in Queensland between September 2013 and September 2014 (refer Appendix 8). The trial examined the potential effects of LWD on vegetation composition and soil properties. The trial plots were established on four geographically diverse trial plots owned by Origin Energy. The trial plots were delineated and soils and vegetation sampled pre and post landspray application. Drilling by-products applied were risk assessed prior to the application, then sampled at four stages on eight different drilling locations. Post application sampling was conducted over a six month period with biweekly monitoring undertaken to gather information required for the final report. In total, 1,638 surface and sub-soil samples, and 192 vegetation samples were obtained and analysed during the trial period. The URS study conclusion stated: From an environmental risk perspective, the trial has generally Doc Ref: Q RP-1399 Revision: 1 Page 19

20 validated the content of the Canadian LWD guidelines, with no measured adverse impact on soil chemistry or vegetation cover or density. (URS, 2014) (Appendix 8). The trial report was submitted to Department of Environment and Heritage Protection (EHP) and the proposed monitoring program was translated into EA conditions for the full scale application of LWD. Queensland Government s Department of Science, Information Technology, Innovation and the Arts also reviewed the URS report and 3rd party audit and did not submit any requests for further information. LWD was approved under State approvals for implementation in August 2015 within the existing Spring Gully CSG Project and the Project area EA Conditions LWD will be undertaken in accordance with the conditions of the Spring Gully EA, which currently are: (H7) Residual drilling material or drilling by-product can only be disposed of on-site: - (a) by mix-bury-cover method if the residual drilling material meets the approved quality criteria, or - (b) by land spraying while drilling method if: (i) the receiving soil where the land spraying while drilling will occur meets the receiving soil criteria (ii) the land spraying while drilling is not conducted within 50m of a downslope water bore, and (iii) the drilling by-product is released in a way that does not result in visible scouring or erosion or pooling or run-off or vegetation die-off. (H8) Prior to the undertaking of land spraying while drilling in the project area, a monitoring program that is able to identify and describe any potential adverse impacts to receiving soils must be developed and certified by a suitably qualified third party. (H9) The land spraying while drilling monitoring program required by condition (H8) must included: - (a) a drilling by-product assessment prior to land spraying while drilling - (b) a receiving soil assessment where drilling by-product is to be disposed - (c) a sampling frequency that is able to reliably assess any changes to receiving soil resulting from land spraying while drilling, and - (d) a soil end point assessment within 60 days of land spraying while drilling. (H10) The median concentration determined from any soil end point assessment must not exceed the 80th percentile concentration determined from the equivalent receiving soil assessment for any parameters sampled. (H11) If an exceedance has been identified in accordance with condition (H10), the EA holder must - (a) engage a suitably qualified third party to conduct further investigations into the potential impacts of that exceedance, and - (b) notify the administering authority as soon as reasonably practicable after the exceedance is identified. (H12) Records must be kept to demonstrate compliance with condition (H6) to (H11). Doc Ref: Q RP-1399 Revision: 1 Page 20

21 LWD Operations LWD is undertaken in accordance with the Landspray While Drilling Procedure (Q-LNG01-35-AP-0048) (Appendix 9). Prior to the implementation of LWD, a suitably qualified and experienced environmental person verifies that the receiving environment complies with operating requirements. Prior to any proposed LWD activity a desktop (geographic information system (GIS)) assessment will be carried out, with subsequent field verification to ensure the receiving environment complies prior to LWD operations. This includes ensuring that the receiving environment within the proposed Well Disposal Areas (WDAs): Has a slope of less than 5%. Is not within 10m of a property track or road drainage. Is not within 50m of a property boundary. Is not within 100m of a downslope water body. Is not within native woody vegetation. Is not within 50m of a water well, bore or livestock water point. Excludes cattle access for a one month period or rainfall event (if sooner) following application. Receiving environment soils will also be tested prior to LWD activities commencing to ensure they comply with the EA receiving soil parameters outlined in the EA. Prior to land spraying commencing, every mud system is tested in the field to ensure the mud and additives are within chemical and toxicity parameters (including validation laboratory analysis at required rates) to ensure consistent best practice minimal disturbance drilling. Origin Energy has been working with Canadian-based companies to develop the fit for purpose technology required to ensure the success of LWD operations in Australia. The purpose-built vacuum trucks are designed for on and off-road conditions with tri-drive 10 by 4 chassis to effectively spread the weight of the drilling by-product across the front and rear of the truck during transport from the rig to the spray field or to facility. Summit earth Navigator (refer to Figure 2) is a GPS-based tracking system that ensures accurate recording of spray field data. The system is programed to open and close autonomously when entering and exiting a mapped spray field. The system records spray swath location, width and length and also calculates the total area sprayed for each well. The Summit Earth system has been installed in each LWD truck and is programmed for each disposal by an onsite environmental advisor to ensure the following parameters are met: Application rate is reflective of the drilling by-product analysis, with a maximum application rate not exceeding 40m 3 /ha. Spray swath programed to maximum potential width based on drilling by product weight, usually set at 11m width in field. Programmed to allow 2m width between spray swaths mapped to ensure that no overlapping or spray drift occurs in field. The programmed criteria must be met before the spray system will engage, opening the pneumatic values within the mapped spray field once at the correct speed, pressure and in line with the AB guidance. While spray drift was one of the initial concerns and monitored during the trial, onsite monitoring concluded spray drift was not an issue due to the density of the drilling by-product. On site mitigation measures to any unlikely spray drift in cross winds have been considered and spray swath witdth maximums measured for each unit. Additionally, a 2m gap is programmed into the Summit Earth Navigator System to ensure the drilling by-product stays within the approved spray fields. Doc Ref: Q RP-1399 Revision: 1 Page 21

22 An example of a site undergoing LWD and five months after spraying is presented in Figure 3. In truck Summit Earth Navigator tablet Report output from GPS tracking of LWD spray swaths Figure 2: Summit Earth Navigator System Vac Truck during operations in field Spray field 5 months after spraying Figure 3: LWD Spray Field Example Doc Ref: Q RP-1399 Revision: 1 Page 22

23 2.9. Changes to Project Description The CSG water management strategy, as described in the Spring Gully Coal Seam Gas Water Management Plan (Spring Gully CWMP) (CDN/ID ) (Appendix 10), maximises beneficial uses in order to deliver sustainable outcomes that protect environmental values (EVs) whilst balancing social and economic considerations. In the original Spring Gully North-West and North-East Referral, it was proposed to manage CSG water via the following: Beneficial use of 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). Irrigation and stock watering in accordance with the General Beneficial Use Approval Irrigation of Associated Water (including coal seam gas water) (General BUA for Irrigation of Associated Water) (DEHP 2014b). Aquifer injection of treated water into the Precipice sandstone. Intermittent contingency release of treated water to Eurombah Creek when the inherent variability of irrigation demand means that a proportion of the treated water cannot be beneficially used. Re-evaluation of the CSG water management strategy has been recently undertaken to remove the reliance on contingency release to Eurombah Creek. As a result, the management of both treated and untreated CSG water from the Project will be via the following: Beneficial use of water for Project activities (including construction, dust suppression and landscaping and revegetation) in accordance with the General BUA (DEHP 2014a). Irrigation in accordance with the General BUA for Irrigation of Associated Water (DEHP 2014b). Aquifer injection of treated water into the Precipice sandstone. Further details on the CSG water management strategy is provided in Section 3.3. The information presented in this preliminary documentation reflects this change and as a result, the assessment of potential impacts to surface water or the White-throated Snapping Turtle has not been included for the release of treated CSG water associated with this Project. The assessment of potential impacts associated with the other management options has not changed as a result of the conservatism that was applied in the referral. Groundwater modelling was undertaken assuming all of the water produced by the Project is injected and the potential impacts are summarised in Sections 6.8 (hydrological), 6.9 (groundwater quality) and 6.10 (cumulative). Potential surface water impacts associated with irrigation and Project activities are discussed in Section 7.2. Doc Ref: Q RP-1399 Revision: 1 Page 23

24 3. CSG Water and Brine Management 3.1. CSG Water Production Profile The Project is expected to produce approximately 7,800ML of CSG water peaking in August 2021 (refer to Figure 4). CSG Water Production Water Production (ML/d) /07/ /04/ /01/ /10/ /07/ /04/ /01/ /10/ /07/ /04/ /01/ /10/ /07/ /04/ /01/ /10/ /07/ /04/ /01/ /10/ /07/ /04/ /01/ /10/ /07/ /04/ /01/ /10/2065 Axis Title 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0 Cumulative Water Production (ML) Water Production Cumulative Water Production 3.2. CSG Water Quality Figure 4: CSG Water Production for the Project 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. Change in temperature to approach ambient values. Doc Ref: Q RP-1399 Revision: 1 Page 24

25 Table 3 summarises the quality of CSG water produced in the SGRA. This is based on pond water that has been pumped from the pond to the WTF and undergone coarse filtration to remove particulates. Water produced by the Project is expected to be a similar quality. Table 4 presents a summary of the quality of CSG water after it has been treated at the WTF based on sampling of the combined permeate stream at the WTF. Table 3: Untreated CSG Water Quality Parameter Unit Limit of reporting No. of Samples No. of Detects 20th %ile detected concentration Median detected concentration 80th %ile detected concentration Inorganics Alkalinity (Bicarbonate) as CaCO3 Alkalinity (Carbonate) as CaCO3 Alkalinity (Total) as CaCO3 mg/l mg/l mg/l Ammonia as N mg/l Bicarbonate mg/l Bromide mg/l Calcium mg/l Carbonate mg/l Chloride mg/l Electrical Conductivity (Lab) µs/cm Fluoride mg/l Iodide mg/l Magnesium mg/l Nitrate (as N) mg/l Nitrite (as N) mg/l Nitrite + Nitrate (as N) mg/l Nitrogen (Total) mg/l Ortho Phosphorus (as P) (Filtered) mg/l Doc Ref: Q RP-1399 Revision: 1 Page 25

26 Parameter Unit Limit of reporting No. of Samples No. of Detects 20th %ile detected concentration Median detected concentration ph (Lab) ph Units Phosphorus mg/l Potassium mg/l Saturation Index Silicon as SiO2 mg/l Sodium mg/l Sulphur as SO4 mg/l th %ile detected concentration Suspended Solids Total Dissolved Salts Total Dissolved Solids Total Dissolved Solids (Calc) Total Hardness as CaCO3 mg/l mg/l mg/l mg/l mg/l Turbidity NTU Metals Aluminium mg/l Arsenic mg/l Barium mg/l Boron mg/l Cadmium mg/l Chromium (III+VI) mg/l Cobalt mg/l Copper mg/l Iron mg/l Lead mg/l Lithium mg/l Doc Ref: Q RP-1399 Revision: 1 Page 26

27 Parameter Unit Limit of reporting No. of Samples No. of Detects 20th %ile detected concentration Median detected concentration Manganese mg/l Molybdenum mg/l Nickel mg/l Selenium mg/l ND ND ND Silver mg/l Strontium mg/l Tin mg/l th %ile detected concentration Zinc mg/l Organic Total Organic Carbon as C mg/l ND not detected Parameter Inorganics Alkalinity (Bicarbonate) as CaCO3 Alkalinity (Carbonate) as CaCO3 Alkalinity (Total) as CaCO3 Unit Limit of reporting Table 4: Treated CSG Water Quality No. of samples No. of detects 20th %ile detected concentratio n Median detected concentratio n mg/l mg/l mg/l Ammonia as N mg/l Bicarbonate mg/l Bromide mg/l Calcium mg/l Carbonate mg/l Chloride mg/l th %ile detected concentratio n Doc Ref: Q RP-1399 Revision: 1 Page 27

28 Parameter Electrical Conductivity (Lab) Unit Limit of reporting No. of samples No. of detects 20th %ile detected concentratio n Median detected concentratio n µs/cm Fluoride mg/l Iodide mg/l Magnesium mg/l Nitrate (as N) mg/l Nitrite (as N) mg/l Nitrite + Nitrate (as N) 80th %ile detected concentratio n mg/l Nitrogen (Total) mg/l Ortho Phosphorus (as P) (Filtered) ph (Lab) mg/l ph Units Phosphorus mg/l Potassium mg/l Residual Alkali as Na2CO3 Saturation Index meq/l Silicon as SiO2 mg/l Sodium mg/l Sodium Absorption Ratio Sulphur as SO4 mg/l Suspended Solids Total Dissolved Salts Total Dissolved Solids Total Dissolved Solids (Calc) Total Hardness as CaCO3 mg/l mg/l mg/l mg/l mg/l Turbidity NTU Metals Doc Ref: Q RP-1399 Revision: 1 Page 28

29 Parameter Unit Limit of reporting No. of samples No. of detects 20th %ile detected concentratio n Median detected concentratio n Aluminium mg/l Arsenic mg/l ND ND ND Barium mg/l Boron mg/l Cadmium mg/l Chromium (III+VI) mg/l ND ND ND Cobalt mg/l ND ND ND Copper mg/l Iron mg/l Lead mg/l Lithium mg/l th %ile detected concentratio n Manganese mg/l Molybdenum mg/l Nickel mg/l ND ND ND Selenium mg/l ND ND ND Silver mg/l ND ND ND Strontium mg/l Tin mg/l Zinc mg/l Organic Total Organic Carbon as C ND- not detected mg/l CSG Water Management Strategy As described in Section 3.1, the Project is expected to produce approximately 7,800ML of CSG water and will be managed in accordance with the Spring Gully CWMP (refer Appendix 10). The plan has been developed in accordance with the Spring Gully EA (EPPG ) and section 126 of the EP Act and has been updated to include the Project s water and brine production profiles. A review of the CSG water management strategy for the existing Spring Gully Project and this Project has been recently undertaken to remove the reliance on contingency release of treated CSG water to Eurombah Creek. The assessment identified the following as the preferred options: Increase the irrigation demand by constructing a centre-pivot irrigation scheme (third party operated) in addition to operating the existing Pongamia plantation. Increase the current performance on the injection scheme whilst maintaining compliance with the Spring Gully EA. Doc Ref: Q RP-1399 Revision: 1 Page 29

30 These options remove the need for the Project s CSG water management strategy to include contingent release to Eurombah Creek. Separate to this referral, it is proposed that contingent release to Eurombah Creek of CSG water generated from existing operations at Spring Gully will also cease. This is planned to approximately coincide with the commissioning of the first well from the Project. In the interim, release to Eurombah Creek as part of the existing Spring Gully operations will continue to support the existing beneficial use schemes. For the Project, both treated and untreated CSG water produced by the Project will be managed via the following: Beneficial use of water for Project activities (including construction, dust suppression and landscaping and revegetation) in accordance with the General BUA (DEHP 2014a). Irrigation and stock watering in accordance with the General BUA for Irrigation of Associated Water (DEHP 2014b). Aquifer injection of treated water into the Precipice sandstone. No treated water from the Project is proposed to be released to Eurombah Creek as part of this referral. This has been confirmed as unnecessary based on the current water production profile, performance on the injection scheme and the proposed expanded irrigation scheme. The CSG water management strategy will continue to be reviewed and changes made where necessary to maximise beneficial use whilst ensuring the protection of environmental values and balancing social and economic factors Water Balance Model A water balance model has been developed to simulate the performance of CSG water and brine management infrastructure and is used to optimise the 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 evaluate 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. 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. The water balance model for the SGRA has been updated to include the Projects CSG water (refer to Spring Gully CWMP in Appendix 10). The water produced by the Project and the existing Spring Gully CSG Project (after the transition period as described in Section 3.3) will be beneficially used as follows: Irrigation average annual irrigation rate of approximately 5.6ML/d (including the proposed expansion) with a 350ML buffer storage dam. Maximum irrigation rate of up to 16ML/d. Injection - average annual capacity of 3.5ML/d with a maximum injection rate of 5ML/d. For conservatism, the use of CSG water for Project activities was not included in the water balance model as the demand is not continuous or long term. Refer to Section and 3.4 of the CWMP for details on the irrigation modelling and water balance model respectively. Doc Ref: Q RP-1399 Revision: 1 Page 30

31 To ensure that the methodology and assumptions of the water balance model remain appropriate to any changes in the CSG water management strategy, the model undergoes monthly recalibration and validation. For the assessment of impacts to water resources as a result of the management of CSG water produced by the Project, the following activities have been assessed: All of the water produced by the Project injected into the Precipice. This is a conservative approach to ensure the maximum potential impacts have been assessed. There are no potential impacts to surface water as a result of injection into the Precipice. Potential groundwater impacts are detailed in Section 6.8 and 6.9. Irrigation and stock watering potential surface water impacts are detailed in Section 7.2. Project related activities - potential surface water impacts are detailed in Section CSG Water Treatment The CSG water will be transferred via the water gathering flowlines to the existing approved facilities on PL195 where it will be stored and treated at the Spring Gully WTF via reverse osmosis (RO) desalination. Where practical and where it can be conducted in accordance with the BUA and the CWMP, CSG water will be beneficially used without treatment at the WTF. The treatment process is presented in Figure 5 and comprises: Temporary storage in the feed pond to provide buffer storage, aeration and removal of coarse sediment and to allow for a reduction in the temperature of CSG water prior to entering the facility. Pre-treatment technologies to remove larger particles and adjust ph to improve the desalination process. Desalination using RO. Conditioning of treated CSG water to ensure suitability for end use. The process of RO generates two (2) products, treated CSG water and brine. Doc Ref: Q RP-1399 Revision: 1 Page 31

32 3.6. Brine Ponds Note: Figure does not show recycle lines used to recirculate off-specification water Figure 5: CSG Water Treatment Simplified Process Flow Diagram Brine produced during the RO desalination of CSG water at the WTF are stored in ponds designed, constructed and operated in accordance with the Manual for Assessing Consequence Categories and Hydraulic Performance of Structures (DEHP 2016) and regulatory approval requirements. Brine management is further discussed in Section CSG Water Use As described in Section 3.3, the CSG water management strategy maximises the beneficial use of CSG water by implementing a portfolio of CSG water uses. Use of CSG water in the SGRA is authorised under one of the following approvals and agreements, as listed in Table 5. CSG Water Use Activity Use of untreated CSG water and/or treated CSG water for Project activities Table 5: CSG Water Use Approvals Approval General BUA (DEHP 2014a) Use of treated CSG water for irrigation Irrigation General BUA (DEHP 2014b) Use of treated CSG water for stock watering and incidental land management General BUA (DEHP 2014a) Doc Ref: Q RP-1399 Revision: 1 Page 32

33 CSG Water Use Activity Use of treated CSG water for aquifer injection Approval Spring Gully EA EPPG Spring Gully Aquifer Injection Management Plan (Appendix 11) Project Activities Both untreated and treated CSG water will be used to support Project activities such as drilling, workover and completions, hydrotesting of gathering network, dust suppression and landscaping and revegetation. 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. Any use of untreated and treated CSG water to support Project activities will be conducted in accordance with the General BUA Irrigation and Stock Watering The irrigation of 285ha of Pongamia (Pongamia pinnata) has been operational since 2010 in SGRA using CSG water in accordance with the General BUA for Irrigation of Associated Water (DEHP 2014b). CSG water produced by the Project will also be used to support the irrigation scheme. A third party operated centre pivot irrigation scheme with a 350ML dam is proposed to increase the beneficial use demand and CSG water produced by the Project will be used to support the scheme. In total, irrigation is expected to deliver an average annual capacity of approximately 5.6ML/d with a maximum rate of up to 16ML/d. Treated CSG water has also been used historically for stock watering in accordance with the General BUA (EHP 2014a) in the SGRA. CSG water produced by the Project may also be used to support this beneficial use in the future Injection An aquifer injection scheme is currently operating in PL195 which injects treated CSG water in the Precipice Sandstone as authorised under the Spring Gully EA. The system includes three injection bores with a capacity to inject up to 8.1ML/d but currently operates at an annual average of 1.5ML/d as a result of operational reliability. As described in Section 3.3, an increase to the current performance on the injection scheme is proposed to achieve an instantaneous capacity of 5ML/d and an annual average capacity of 3.5ML/d. Treated CSG water produced by the Project will also be injected in accordance with the EA and the Spring Gully Aquifer Injection Management Plan (Appendix 11). For the purposes of the assessment of impacts from aquifer injection, it is assumed that all water produced by the Project will be injected. CSG water is treated at the WTF as described in Section 3.5 and the water from the permeate tank is then transferred to the Spring Gully Permeate Reinjection Plant (PRP). The water is treated by the following processes as described below and shown in Figure 6 prior to being injected into the Precipice Sandstone. The proposed injection of treated CSG water is required as a result of the management of CSG water. The use of injection as a mitigation measure for CSG water extraction is not required due to the minor drawdown predicted as a result of the Project which is within the natural daily variations from barometric pressure changes. Doc Ref: Q RP-1399 Revision: 1 Page 33

34 Flow-Paced Biological Control In the first stage in the PRP treatment process, monochloramine is added to the water to control biological fouling on the degasification membranes Disinfection Downstream of the feed pumps, the PRP has the capacity for disinfection of the CSG water by ultraviolet. The purpose of this treatment step is to remove any biological risk associated with the CSG water being temporarily stored in the permeate tank which is partially open to the atmosphere. Ultra-violet intensity monitoring (two sensors) ensures that the required dose rate is achieved, otherwise water is flushed to the feed pond for reprocessing. This step is only required if six-monthly testing of the water shows levels of bacteria which have potential to cause adverse impacts on the groundwater in the target formation Cartridge Filtration Although the RO process removes all particulate matter, the potential exists for limited amounts of particulate matter to enter the CSG water while it is stored in the permeate tanks. The cartridge filter will remove this particulate matter, but also serves to protect the degasification membranes should the ultra-violet lamp shatter and enter the water stream 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 water and across the membrane. This step is optional as identified in the geochemical modelling detailed in Section Oxygen Scavenger and Corrosion Inhibitor Sodium erythorbate (C 6 H 7 NaO 6 ) is an anti-oxidant used in various foods and as a corrosion inhibitor in boiler feedwater. It has approval for use in foods in the European Union and is increasingly used in Australia (Versari et al. 2004). Sodium erythorbate (food grade, 99% purity) is added to the CSG water at a concentration entering the injection bore of approximately 3mg/L. The purpose of this additive is to inhibit the corrosion of the carbon steel bore casing Injectate Monitoring The degassed CSG water is continuously analysed for ph, dissolved oxygen (two sensors), and conductivity at the outlet of the PRP, prior to conveyance to the injection bores. Should the observed parameters deviate from engineer specified control points, automated isolation valves redirect the water back to either the PRP permeate tank via the recirculation line, or to the feed pond, depending on the operational mode of the water treatment plant at that time. Taps are installed downstream of all treatment processes to allow collection of injectate samples for laboratory analysis. Doc Ref: Q RP-1399 Revision: 1 Page 34

35 Figure 6: PRP Process Flow Diagram 3.8. Brine Management Up to 1.5ML/d of brine and 45,500 tonnes of salt will be produced as a result of the Project (refer to Figure 7) which will also be managed in accordance with the Spring Gully CWMP. Currently it is proposed that brine will be stored within existing brine ponds in the Spring Gully CSG Project area. Four options for brine management have been identified and assessed in a two gated process. The four options were selective salt recovery, brine injection, ocean outfall and encapsulation. The first gate was a fatal flaw analysis of the option requiring it to be compatible with the following requirements: 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. 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. Doc Ref: Q RP-1399 Revision: 1 Page 35

36 As discussed in the CWMP in Appendix 10, the current preferred long term brine and salt management option is encapsulation as it has the lowest environmental impacts and cost of the options considered. The encapsulation 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 Regulated Waste Facility (RWF). The scheme s key processes incorporates the following: Storage and solar evaporation of brine in brine ponds brine produced by the WTF (total dissolved solids circa 30g/L) 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 250g/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 RWF. Brine crystallisation to solid salt two regional crystallisers and RWFs are proposed for Australia Pacific LNG tenures. 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 outside the SGRA. 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. Further details on brine and salt management including the long term management strategy is provided in Sections 4 and 5.3 of the Spring Gully CWMP (Appendix 10). Doc Ref: Q RP-1399 Revision: 1 Page 36

37 Brine and Salt Produced by the Project ML/d /04/ /02/ /12/ /10/ /08/ /06/ /04/ /02/ /12/ /10/ /08/ /06/ /04/ /02/ /12/ /10/ /08/ /06/ /04/ /02/ /12/ /10/ /08/ /06/ /04/ /02/ /12/ ,000 45,000 40,000 35,000 30,000 25,000 20,000 15,000 10,000 5,000 0 Tonnes Brine Salt Mass Figure 7: Brine and Salt Production Doc Ref: Q RP-1399 Revision: 1 Page 37

38 4. Social and Economic Matters Australia Pacific LNG undertook a voluntary Social Impact Assessment (SIA) in 2014 in anticipation of the transition from the construction phase to the operational phase of the Australia Pacific LNG Project. Findings from the SIA (although not specifically investigating change incurred by this project), are largely applicable to this Project 1. The findings and management actions from the voluntary SIA have been incorporated into ongoing social management plans and procedures which apply both this Project and the Australia Pacific LNG Project. Australia Pacific LNG is committed to ongoing consultation and engagement with stakeholders across the region, including landholders, indigenous communities, general community members and community groups. Australia Pacific LNG has a dedicated team of community and landholder engagement specialists deployed across the region to implement this engagement. Construction costs, duration and employee numbers for this Project will depend on a range of factors which are not know at the time of submission 2. Typically however, construction projects of this magnitude last for approximately 12 to 18 months (assuming all wells are drilled sequentially), and the number of field based employees fluctuate between approximately 30 and 100 during this time. Construction contractors typically source their labour force from the local and regional area as well as state wide. The construction employees are likely to be located in various forms of local accommodation, which may include motels, rented accommodation or temporary accommodation facilities, dependent on availability and impacts to the local housing market. Where relevant, Australia Pacific LNG will require contractors to complete Regional Participation Plans and Indigenous Participation plans, aiming to maximise local and indigenous content. The ongoing operation of the project will be carried out as an extension of the current Australia Pacific LNG operations, which currently employ approximately 440 field based employees. Australia Pacific LNG encourages its permanent operational employees to relocate to and reside in the Surat region by providing regional and local living allowances. Further, Origin who is the upstream operator of Australia Pacific LNG, has made commitments to improve indigenous participation in its workforce and supply chain through its Reconciliation Action Plan. Australia Pacific LNG Project provides economic benefits to local, regional and state economies. For example, Origin as the upstream operator of the Australia Pacific LNG project: Has spent approximately $23 million on community investment projects since project inception in Directly employed 531 people based in the Surat basin region by the end of June 2017, and paid $89 million in regional wages during the financial year. 157 of these employees were regional residents. In addition, 91 employees on fly in and fly out arrangements were based in rental accommodation in regional towns. Spent $87.5 million with 190 businesses in the Surat basin region during the FY16/17 financial year. In addition, Origin s contractors spent a minimum of $55.2 million across 349 regional businesses. Negotiated and committed an additional $70 million in compensation payments for landholders for our development wells during the 2016/2017 financial year. 1 Findings from the SIA can be summarised as regional economic impact from construction ramp down, ongoing business and employment opportunities, property and landholder level impact from negotiations and construction activities and lack of project information at a regional scale 2 These are subject to, among others, detailed design, engineering and procurement considerations. Construction costs, operation costs and project revenue are difficult to determine in advance and are of a commercial in confidence nature. Doc Ref: Q RP-1399 Revision: 1 Page 38

39 Australia Pacific LNG provides six monthly reports on its environmental and social performance. These reports are available to the public on the Australia Pacific LNG website. Doc Ref: Q RP-1399 Revision: 1 Page 39

40 5. Listed Threatened Species and Communities Five TECs, 10 listed threatened fauna and three listed threatened flora have been confirmed, are likely to or have the potential to occur within the Project area. Further assessment has been undertaken on the following species including further refinement of potential habitat and a targeted field survey (Appendix 12 and Appendix 13): White-throated Snapping Turtle (Elseya albagula) critically endangered. Koala (Phascolarctos cinereus) (combined populations of Queensland, NSW and the ACT) vulnerable. Greater Glider (Petauroides volans) vulnerable. Squatter Pigeon (Geophaps scripta scripta) vulnerable. Brigalow (Acacia harpophylla dominant and co-dominant) endangered. Northern Quoll (Dasyurus hallucatus) endangered. Bertya opponens (a shrub) vulnerable. Large-eared Pied Bat (Chalinolobus dwyeri) vulnerable. Yakka Skink (Egernia rugosa) vulnerable. Dunmall s Snake (Furina dunmalli) vulnerable. South-eastern Long-eared Bat (Nyctophilus corbeni) vulnerable. Collared Delma (Delma torquata) vulnerable White-throated Snapping Turtle Introduction Boobook Ecological Consulting (Boobook) has completed a survey for White-throated Snapping Turtle (Elseya albagula) in May 2017 at Eurombah Creek (refer to Appendix 12 for the full report). The objectives of the survey included: Survey of the White-throated Snapping Turtle in Eurombah Creek within and adjacent to the Project area, to be undertaken by a suitably qualified expert and with reference to current best practice survey approaches. Detailed mapping of the known and potential suitable habitat for the White-throated Snapping Turtle within and adjacent to the Project area. A habitat assessment, including but not limited to the area (in hectares), quality, location and use specifications, of known and potential suitable habitat for the species in Eurombah Creek in relation to the Project disturbance area, both within and downstream of the Project area Suitably Qualified Experts White-throated Snapping Turtle is listed as Critically Endangered under the EPBC Act. Boobook was therefore commissioned to undertake this survey as they are considered to be suitably qualified experts in undertaking ecological surveys within the Brigalow Belt bioregion. Collectively, the ecologists who were engaged to undertake the surveys have over 40 years of ecological survey experience within the Surat Basin. This experience includes the working knowledge of the identification, distribution and ecology of freshwater turtles, including the surveying for and handling of White-throated Snapping Turtle. Doc Ref: Q RP-1399 Revision: 1 Page 40

41 The key personnel from Boobook have conducted a combined total of over 650 surveys for threatened species, threatened ecological communities, regional ecosystems and wetlands throughout the Brigalow Belt bioregion and are expert panel members for the EHP Back on Track II species prioritisation framework and are members for the World Wildlife Fund Brigalow Belt Reptiles Recovery Team. Of additional importance, they have conducted several environmental impact assessments of threatened species listed under the EPBC Act and include: Craig Eddie (Principal Ecologist) who has more than 20 year s field ecology survey experience within the Brigalow Belt bioregion. Specifically relating to experience of species of turtle, Craig has undertaken the following surveys for freshwater turtles in southern inland Queensland: - Survey of turtles at Carnarvon Gorge and Lonesome Holding (including White-throated Snapping Turtle) in the Fitzroy-Dawson catchment, and at Mount Moffatt and Murra Murra (Warrego River, Nebine Creek, Murray-Darling catchment). - Turtle survey and trapping (including White-throated Snapping Turtle) as part of a general fauna survey within Eurombah Creek. Richard Johnson (Senior Ecologist) who has more than 20 years field ecology survey experience within the Brigalow Belt, including specific experience relating to surveys of freshwater turtles in southern inland Queensland and the Dawson River catchment, including: - Survey of turtle (including White-throated Snapping Turtle) mortalities associated with water releases at Glebe Weir, Dawson River. - Trapping and tagging of turtles (including White-throated Snapping Turtle) at Glebe Weir and Robinson Creek. - Surveys of turtle drought mortalities, Currawinya National Park. - Turtle survey and trapping (including White-throated Snapping Turtle) as part of a general fauna survey within Eurombah Creek. Collectively, Craig and Richard, with the support of Botanist Rosamund Aisthorpe (assistance required in defining vegetative components of habitat), formed a suitably qualified expert team to survey for the White-throated Snapping Turtle Survey Area The survey extent covered Eurombah Creek within and adjacent to the Project area. As the Whitethroated Snapping Turtle relies on permanent riverine pools, flowing or non-flowing (DoEE 2014), aerial imagery interpretation combined with local knowledge (Boobook 2017c) was used to define potential waterbodies within Eurombah Creek. Potential habitat for aquatic fauna species during non-flow periods was contained in a number of large waterholes within the course of Eurombah Creek between an upstream limit of approximately ºS, ºE, and a downstream limit of approximately ºS, ºE (refer to Appendix 1, Figure 2) Species Ecology and Distribution in Relation to the Survey Area 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). It is the largest species of freshwater turtle in Australia, with a carapace length exceeding 40cm in mature females. Adult turtles are herbivores, feeding on aquatic plants and fallen fruit and leaves from riparian vegetation (Cann 1998, DoEE 2014). The turtle is reliant on the presence of permanent riverine pools, preferably with flowing water though non-flowing waters are also used: the latter may include isolated waterholes during the dry season (DoEE 2014, Limpus et al. 2011). Aquatic macrophytes are important in the diet of adult turtles (Limpus et al. 2011). Doc Ref: Q RP-1399 Revision: 1 Page 41

42 The greatest threat to the species is predation of eggs and nest destruction. Research has shown (Hamann et al. 2004, Limpus et al. 2011) that even though nesting is still commonly occurring in these catchments, approaching 100% of eggs are lost due to predation of the nests by both native and feral predators or by trampling by cattle and other domestic livestock. As a result, the population now consist of aging adults (DoEE 2014). Publicly accessible databases (ALA 2017) show records of the species in the Dawson River as far upstream as Taroom. However, the turtle is known to occur further upstream, being recorded from permanent, spring-fed pools at Korcha (Limpus et al. 2011) and Lonesome Holding (C. Eddie pers. obs.) on the Dawson River and from Warndoo on Hutton Creek (Limpus et al. 2011), a tributary stream rising near Injune. Additionally, the species has been recorded in Eurombah Creek during Origin ecological surveys (Boobook 2017; A. Skelly, Origin, pers. comm.) and has been recorded in pools on the property Nugget Hills during a private fauna survey (Boobook 2014). Eurombah Creek enters the Dawson River approximately 85km east, north-east from the WTF Methodology In the absence of species specific published methodologies, current best practice survey methodologies were utilised. Methodologies included a combination of both desktop and field assessments. Database searches, literature review and aerial imagery interrogation were conducted to inform suitable survey site selection and identify the potential presence of the target species and other potential aquatic fauna, whilst field survey assessments were used to confirm desktop results Desktop Assessments The following desktop assessments were conducted: Database and literature reviews including: - Atlas of Living Australia (incorporating Birdata, museum and herbarium data). - Bureau of Meteorology online climate data (for nearest weather station). - DoEE EPBC Act Protected Matters Search Tool. - DoEE Species Profile and Threats Database. - EHP Wildlife Online Database. - EHP WetlandInfo maps. - DNRM Biodiversity Status of Pre-clearing and Remnant Regional Ecosystems Version DNRM Australia Geological Mapping, 1:250,000 Geological series. - Department of Science, Information Technology and Innovation (DSITI) Regional Ecosystem Description Database. - Origin Energy spatial data (ground-truthing regional ecosystem mapping) and pre-existing ecology reports. Aerial imagery interrogation. Origin Energy issued aerial imagery (recent 2016, and historical 2013), along with Queensland Globe and Google Earth imagery was utilised to identify suitable survey sites where waterholes were present Field Assessments Field surveys consisted of two distinct field survey components, the first being; waterhole watches, which aimed to identify the presence of the target species (White-throated Snapping Turtle), along with any other incidental observations of aquatic fauna species (other turtles, aquatic mammals etc.) within Doc Ref: Q RP-1399 Revision: 1 Page 42

43 the waterholes. The second component included habitat assessments of both riparian and aquatic habitat. Both field survey components are summarised below. Waterhole watches Waterhole watches were conducted to search for the White-throated Snapping Turtles presence within the survey area. This was undertaken in general accordance with recommendations for visual survey of turtles as described in Eyre et al. (2014). Waterhole watches were conducted at 44 survey sites, where deep pools and suitable habitat was likely to be present across Eurombah Creek. Each site was surveyed for a duration of 60 minutes, and was conducted by two observers, watching the same waterhole at different vantage points to effectively visually cover different portions of water surface of each site. Each trained observer would continually scan the water surface using 10x40 binoculars, looking for the presence of turtles. Turtle identification was conducted through visual observation and by distinguishing the five potential species of freshwater turtles (Eastern Long-necked Turtle Chelodina longicollis; Broad-shelled River Turtle Chelodina expansa; White-throated Snapping Turtle Elseya albagula; Krefft s River Turtle Emydura macquarii krefftii; and Saw-shelled Turtle Wollumbinia latisternum) by their differences in features such as head shape, colouration, head scalation, iris colour and where visible, relative neck length and shell shape when viewed dorsally and laterally. Once a turtle (or incidental aquatic fauna) was detected, the species scientific name, common name and the number of individuals were recorded. Visual surveillance of the presence of the species was considered to be an effective survey technique as the species is distinctive (to trained observers) and surfaces to breath relatively frequently. However, survey constraints relating to the seasonal detectability of the species were noted. The survey was conducted in May (autumn) and therefore both air and water temperatures are lower in comparison to summer temperatures. As a result in lower ambient temperatures, turtles lower their metabolic activity as water temperature drops, resulting in less frequent surfacing to the water surface to breath. This may have limited the frequency of turtles breathing at the water surfaces and therefore reduced the likelihood of detection. Additionally, turbidity of waterhole water was also considered a constraint in identifying species presence. Habitat assessments Habitat assessments for the White-throated Snapping Turtle included an assessment of vegetation along the banks of each waterhole and instream characteristics of each site. These assessments were conducted concurrently with waterhole watches. An assessment of adjacent vegetation was carried out at each site, using a quaternary-level assessment as described in Neldner et al. (2012) to identify the regional ecosystem present. Parameters assessed included: Height (median and maximum/minimum) and % cover of each stratum of vegetation (i.e. ground, shrub, tree and emergent layers). Dominant flora in each stratum of vegetation. Regional ecosystem type observed. Soil descriptions (as per McDonald et al. (1990)). An assessment of instream characteristics was carried out at each site and included the following parameters: Width of waterhole. Approximate length of waterhole (interpreted from imagery). Apparent presence and extent of deep water (i.e. >1m depth). Doc Ref: Q RP-1399 Revision: 1 Page 43

44 Water turbidity. Temperature (measured at a depth of m below surface and adjacent to the bank); Presence of aquatic macrophyte beds. In-stream timber and rock. Any special topographic features (e.g. bank configuration). Classification of habitat (waterholes) was defined as: Confirmed where the White-throated Snapping Turtle was detected. Suitable where physical attributes were similar to confirmed sites +/- presence of obligate aquatic vertebrates. Unlikely where physical attributes similar to confirmed sites +/- presence of obligate aquatic vertebrates were absent Results and Discussion Survey Conditions The survey was conducted over two 5-day periods in weeks 1-5 May and May 2017 and were generally undertaken between 0630 and 1730 hours. The first survey period featured mild, fine weather except for 4 May when light rain fell (preventing access to survey sites). The second survey period was cooler, with cool to cold mornings for the duration of the survey and a rain event that prevented surveying on 19 May. Water temperatures in survey period two, were 2ºC lower than that of the first survey period which had a mean temperature of 19.7ºC. Prior to the first survey period, Eurombah Creek had experienced a minor flood following heavy rain associated with Cyclone Debbie in March (BOM 2017). Since that time, the water level had dropped m, as evident by silt staining on bankside vegetation Survey Site Characteristics Forty-four (44) survey sites were surveyed. Water in Eurombah Creek was turbid, with visibility restricted to a few centimetres depth. This affected the visibility of turtles and the ability to assess instream habitat features such as macrophytes, logs and rocks. Waterholes on Eurombah Creek from site TS15 upstream were found to be generally long (several hundred metres) with relatively short intervening stretches of dry bed which would form riffle areas during flow periods. Waterhole length, as measured on imagery (dated 28 Nov 2013) ranged from 125m to 1640m. The summed length of waterholes present at that date for the stream reach from TS15 to the upstream limit of waterholes was approximately 32.8km. Width generally ranged from 15m to 25m (exceptionally to 30m). These data will vary with seasonal conditions but are in general accordance with findings reported previously by Lewis and Hansen (2009). The crest of the low bank was usually m but up to 3.0m above the water level. Riparian woodland of Eucalyptus tereticornis and Casuarina cunninghamiana, with Angophora floribunda occasionally present as an associated species, was present on the margins of all waterholes, extending varying distances landward on bank slopes and alluvial terraces. This vegetation community corresponds with the description of regional ecosystem (RE) (Eucalyptus tereticornis or E. camaldulensis woodland fringing drainage lines) (DSITI 2017). Soils were mostly sandy to silty loams, with clay enrichment at some sites. No inter-channel sandbanks were seen. The presence of riparian vegetation on alluvium was considered to indicate the presence of alluvial soils suitable as turtle nesting habitat (Limpus et al. 2011). Doc Ref: Q RP-1399 Revision: 1 Page 44

45 The grassy ground layer at the majority of sites was dominated by non-native pasture grasses, particularly Green Panic (Megathyrsus maximus). Cattle grazing was evident throughout the survey area; impacts such as bank trampling and eroded tracks were commonly seen. There is some evidence that waterholes within the creek are fed by spring discharge. A spring (W59) is reported to be present on Eurombah Creek, discharging from the Upper Hutton sandstone aquifer (DNRM 2016). A flowing spring was seen near the given location for W59 during the survey, discharging into the creek via a gully. A smaller spring was seen on the banks of the creek approximately 450m upstream. Seepage of water from outcropping sandstone was seen at site TS Presence of White-throated Snapping Turtle One or more White-throated Snapping Turtles were observed at seventeen (17) sites, or 38.6% of sites (refer to Appendix 1, Figure 2). Of the other sites (27 sites), all but two were assessed as suitable habitat for the species. The remaining two sites were found to be narrow, shallow pools with no evidence of turtles or other aquatic vertebrates. Sightings of the turtle were generally brief, with one or sometimes two animals seen to surface briefly before diving again. During the first week of surveys the turtle was encountered throughout the day. During the second week, which featured cool to cold mornings, little turtle activity was apparent during the morning and early afternoon, with sightings being made later in the afternoon. An exception to this was on the last day of survey (18 May 2017), which was a mild overcast day with some showers developing. White-throated Snapping Turtles were seen from late morning to late afternoon at three of the four sites surveyed in that period. At one of these sites (TS43) an aggregation of two adult female and four adult males was seen in the pool, as well as a single animal with an estimated carapace length of mm. Animals of this size are juveniles (Cann 1998; C. Limpus, DEHP, pers. comm.) but as data on growth rates is not available an age estimate cannot be made. Two of the adult males spent much time floating on the surface. This may have been part of courtship and mating behaviour but mating could not be confirmed. The turtle was recorded at site TS33, approximately 6km downstream from the apparent upper limit of waterholes. Four more sites were surveyed upstream of TS33 and all were found to be suitable habitat, based on an assessment of the physical and biotic features of the waterholes. The furthest downstream the species was found was at site TS15. Only one other site was surveyed downstream of TS15 and this site was assessed as unlikely habitat. TS15 may represent the downstream extent of suitable habitat. Hence it appears that the White-throated Snapping Turtle may be present in Eurombah Creek from the upstream limits of permanent water downstream to site TS15, a distance of approximately 45.1km. This extent appears to largely coincide with that of the creek s intersection with the Hutton Sandstone, supporting the possibility that turtle habitat is provided by spring-fed pools that withstand drought. That is, currently undocumented springs may maintain the pools along this reach. For example, anecdotal advice from one landholder was that the pool surveyed at site TS28 has never dried in his 70 years of experience. This survey aimed to detect the presence of the target species, such that survey methodology was directed to rapid presence only survey of multiple sites. Though the number seen of the species was recorded there was no attempt to develop an estimate of the population of the species within the survey area. Despite this limitation it was apparent that the White-throated Snapping Turtle is reasonably common within the stream reach examined. In total, 25 animals were recorded during the survey. The great majority of waterholes examined were deep with little or no flow at the time of the survey. Though evidence of aquatic macrophytes was seen at only one site, there is evidence to suggest that these are more extensive in more favourable conditions. These waterholes appear to conform to the description of preferred feeding habitat given by Micheli-Campbell et al. (2017). The record of a juvenile animal is an indication that breeding may occur within the reach. Soils apparently suitable for nesting are present within the survey area. Doc Ref: Q RP-1399 Revision: 1 Page 45

46 White-throated Snapping Turtle Habitat Aquatic and terrestrial (nesting) habitat was confirmed within the survey area. Aquatic habitat Examination of the waterholes at 42 of 44 sites showed them to be deep pools with fringing riparian woodland. The pools contained variable amounts of emergent large timber (snags) and rock. Beds of aquatic macrophytes were only seen at one site. Because the water was turbid it was not possible to say whether this turbidity masked the presence of such beds or whether they were absent. Examination of waterholes in Eurombah Creek during periods of nil flow and relatively clear water has shown extensive beds of macrophytes such as Nitella sp. and Myriophyllum sp. (Boobook 2014). This suggests that macrophyte beds may be more widespread than was evident during this survey: many beds may have been swept away during the recent flood event. The two remaining waterholes surveyed were considered unsuitable habitat because they were found to be narrow and mostly or entirely shallow, and lacked evidence of the presence of obligate aquatic vertebrates. Published accounts of the biology and conservation management of this turtle (e.g. DoEE 2014, Limpus et al. 2011) have stressed the importance of flowing water for the species. A more recent study (Micheli- Campbell et al. 2017) has challenged this. That study, conducted in the Mary River, South-east Queensland, examined dietary niche separation between this turtle and Elusor macrurus. The authors found that White-throated Snapping Turtles fed on filamentous algae and crustaceans obtained from the shallow margins of deep water pools, rather than foraging in shallow inter-pool riffles with higher flow rates. The waterholes on the surveyed reach of Eurombah Creek conform to that description of foraging habitat. Riffle habitat would be available, albeit for a short period following flood flows, but this does not seem essential to the turtle. High flows would provide an opportunity for migration into and out of the survey area. It is difficult to define precisely how much aquatic habitat is available to the turtle because of contraction and expansion of water levels according to seasonal conditions, as shown by imagery captured at various dates. A precautionary approach to this would be to consider the entirety of the reach described above to be habitat, acknowledging that patterns of usage will vary with water levels. This would capture both the value of deep pools as foraging habitat and as refugia in dry conditions; and the role of temporary shallow riffles in maintaining inter-pool and catchment connectivity. It is possible that the population of turtles in upper Eurombah Creek is isolated from that in the Dawson River for extended periods as it is separated from the river by many kilometres of unsuitable habitat. Terrestrial habitat Published accounts of nesting sites in the Mary, Burnett and Fitzroy Rivers (Hamann et al. 2004, Limpus et al. 2011) indicate that a variety of locations may be used. These include in-stream and on-bank flooddeposited sandbanks as well as sandy to loamy soils on riverbanks, generally above bank slopes. These sites included bare sand/soil and heavily grassed sites (Hamann et al. 2004). Nests were located at a wide range of distances from the water s edge (5-60m), possibly reflecting variability in terrain. Limpus et al. (2011) state that on sandbanks in the Fitzroy River the average distance from the water s edge of nests is 16.6m. While Limpus et al. (2011) concluded that in the Fitzroy River the species may migrate to preferred breeding locations, Micheli-Campbell et al. (2017) found that those turtles that bred within their study area nested locally. Both scattered nests and localised nesting in preferred sites have been reported in the Mary, Burnett and Fitzroy Rivers by Hamann et al. (2004). It seems safe to assume that where adult turtles and apparently suitable nesting habitat are present, breeding may occur. Doc Ref: Q RP-1399 Revision: 1 Page 46

47 Flood-deposited sand- or loam banks were not seen during the survey. However the stream banks at most sites comprised friable sandy to silty loams with a mid-dense cover of grass (usually non-native species dominated) below a tree canopy of Eucalyptus tereticornis and Casuarina cunninghamiana. Such areas were consistent with classification as RE Bank slopes above the low bank crest were generally moderate and extended landward to the high bank crest with or without the presence of benches. Exceptions to this occurred where the creek ran against outcropping sandstone on hill slopes: in this situation the riparian community was present as a narrow fringe on the low bank crest. Sites with friable sandy or silty soil (alluvium) on bank slopes and benches appear to provide potential nesting habitat. The width of these features was variable. In general the extent of alluvial deposits was constrained by the valley width, this being most pronounced where the creek ran between rocky hillsides. A juvenile Snapping Turtle, as well as several juvenile and immature Krefft s River Turtles, were recorded during the survey and this is possible evidence of local nesting activity, though these animals may have migrated into the survey area. Extent of habitat Confirmed or suitable aquatic habitat extended from the upper limit of waterholes downstream to survey site TS15, a distance of 45.1km. Given that within this reach waterholes are long and separated only by short distances, and that during flows turtles may forage in riffle areas between pools as well as migrate between waterholes or further, it is assumed that the entirety of the reach constitutes suitable habitat. Field survey showed that for most waterholes, width ranged from 15-25m. This suggests an average width of about 20m, an estimate confirmed by a series of GIS-based measurements of visible pool width. A useable measure of the extent of aquatic habitat is to assume a stream width at low flow of 20m along the entire reach. This method provides an estimated extent of aquatic habitat of approximately 90.3ha. In determining terrestrial (nesting) habitat, field findings on the extent of RE (suitable habitat due to suitable nesting habitat (soil types) and microhabitat features) and published information on the distance from water that turtles may nest was used to determine a distance of 25m to be used to calculate the potential of along Eurombah Creek. However, there are limitations to this approach as available literature indicates that the turtle mostly nests relatively close to the water s edge and the entirety of the riparian vegetation along Eurombah Creek hasn t been ground-truthed. None the less, a precautionary approach in that it over-estimates the true extent landward of the RE in those parts of the creek closely bounded by rocky hillsides, a common situation in this part of the creek. This method provides an estimated extent of terrestrial nesting habitat of approximately 225.9ha Potential Impacts The Project will not include the release of treated CSG water to Eurombah Creek. As a result the potential impacts to White-throated Snapping Turtle and its habitat are limited to the construction of linear infrastructure across Eurombah creek. Approximately 50m of Eurombah Creek will be disturbed by gathering and access track crossings. Construction of the crossings on Eurombah Creek will be undertaken between January and April (inclusive) so as to avoid the nesting, incubation and hatching period unless surveys by a suitable qualified person determine that the construction area will not intersect active nesting sites Terrestrial Threatened Species and Ecological Community Survey Effort A total of 18 ecology surveys and 10 pre-clearance surveys have been undertaken within the Project area to date and are summarised in Appendix 13. Note that some of the surveys were broader projects that Doc Ref: Q RP-1399 Revision: 1 Page 47

48 included surveys outside the Project area (e.g. GHD 2012, 2013) hence only a proportion of the survey effort for some surveys is applicable to the Project. To date, ecology and preclearance survey effort has been concentrated within NWDA. A summary of the methodologies performed within these surveys undertaken within the Project area is described below Fauna Surveys One fauna survey undertaken within the Project area (GHD 2013) was part of a broader study identifying ecological values occurring within the SGRA. Fauna survey methods employed included active searching (5 sites), Anabat call detection (3 sites), spotlighting (2 sites) and funnel trapping (1 site). Survey effort within Project area to date has been minimal. Fauna survey sites applicable to the Project area are shown in Appendix 1 Figure 3. One additional whole-of-property survey (GHD 2012) incorporated the same fauna survey techniques as GHD (2013) however the fauna survey sites were located just outside the NWDA. In summary, no fauna surveys have been completed within the Project area that have been conducted in accordance with commonwealth threatened fauna survey guidelines (DEWHA 2010a, 2010b; DSEWPaC 2011a, 2011b) or best practice state government vertebrate fauna survey guidelines (Eyre et al. 2014). However, as part of the ecology surveys, incidental threatened fauna searches were carried out as described in Section Based on this survey limitation, all potential habitat for MNES fauna species is based on REs and refined in accordance with section Ecology Surveys TEC assessments The potential occurrence of TECs within the Project area has been informed by multiple desktop assessments (e.g. database searches). Typically, TEC ground truthing was undertaken within the Project area by obtaining detailed descriptions of vegetation structure and species composition at representative assessment locations. Vegetation assessments were undertaken within 50m x 10m plots for the purpose of typifying the vegetation community under assessment. Origin-specific field survey protocols required these assessments to be consistent with the quaternary level of detail as per Neldner et al. (2012). At each vegetation assessment site the following is recorded (in line with Neldner et al. 2012): Height (median and maximum/minimum) and % cover of each stratum of vegetation (i.e. ground, shrub, tree and emergent layers). Dominant flora in each stratum of vegetation. RE type mapped. RE type observed. Geology, landform and soil descriptions. Presence and abundance of weeds (declared and non-declared species) as well as estimated % coverage of the site. Data from vegetation survey sites was used to map vegetation community polygons (i.e. REs). Appendix 1 Figure 3 shows the locations of each vegetation assessment site (i.e. quaternary assessment) within the Project area. Where quaternary assessment data has been applied to whole vegetation polygons (rather than just the survey site) these have been mapped within Appendix 1 Figure 3 as Vegetation Assessment Areas. Doc Ref: Q RP-1399 Revision: 1 Page 48

49 The status and type of RE applicable to each vegetation community polygon was verified by referring to the Regional Ecosystem Description Database (DSITI 2017). Information obtained from the quaternary vegetation assessments allows identification of TEC by comparison of results with TEC technical descriptions which include floristic, structural and condition criteria, as well as component REs (TSSC 2013, DoEE 2017a). Once a TEC is confirmed as present delineation of the boundaries of the TEC was undertaken using GPS devices and/or imagery. Notes regarding the quality of TEC were generally made within survey points which capture the types and level of severity of disturbances present. Disturbances relevant to TEC that may be recorded include clearing (including time since clearing which is applicable to Brigalow TEC), thinning/logging, fire and weed invasion. Appendix 1 Figure 3 shows the location of disturbance survey sites throughout the Project area. Habitat and likelihood of occurrence assessments On-ground habitat assessments for threatened species were completed in accordance with Origin s ecology survey methodology (Australia Pacific LNG 2011). In summary, habitat assessments were generally undertaken within a 50m x 10m plot. Within each plot, the presence, % cover or abundance of a range of habitat/microhabitat features was recorded on electronic data capture devices. Such features may be of relevance to threatened fauna and/or flora. Habitat features routinely recorded include: Abundance of logs in various size classes. Abundance of hollow-bearing trees (including various hollow-size categories). Abundance of rocks/stones. Presence of caves/rocky outcrops. Abundance of logs/trees with decorticating (loose) bark. Presence/absence of mistletoe. Presence/absence of food trees. Density of leaflitter. Density of shrub layer. Density of ground layer. Abundance and characteristics of gilgais. Appendix 1 Figure 3 shows the location of habitat assessments which have been completed at over 200 sites within the Project area. The presence/absence or abundance/density of particular habitat features allowed for predictions to be made as to which threatened fauna/flora may potentially be present within an area i.e. likelihood of occurrence assessments. The results of habitat assessments directly informed the likelihood of occurrence assessments performed by ecologists for 10 of the 18 ecology surveys. Likelihood of occurrence assessments for some species were constrained by lack of distribution data or habitat preferences; in these cases likelihood of occurrence assessments were conservative (i.e. where suitable habitat features are present and the species is broadly within its known range that species was assumed to occur until proven otherwise). Threatened flora searches Searches for threatened flora were routinely undertaken within ecology surveys in accordance with Origin s ecology survey methodology (Australia Pacific LNG 2011) for species highlighted by the results of pre-field desktop analysis (i.e. database and literature review). Searches were undertaken at or within the vicinity of vegetation community and/or habitat assessment plots. Additional searches were Doc Ref: Q RP-1399 Revision: 1 Page 49

50 undertaken wherever ecologists deemed any given area to be of sufficient potential value to a threatened species to warrant such a search (e.g. field observations of high quality habitat or identification of distinct ecological features). Threatened fauna searches Active searches for threatened fauna were routinely undertaken during ecology surveys within the Project area. Active searches included direct observations which could have detected diurnal species such as Koala and Squatter Pigeon, indirect observations (e.g. tracks, scats) which could have detected Koala, Northern Quoll and Yakka Skink and physical searches of shelter sites (e.g. logs, rock piles, loose bark) could have detected Dunmall s Snake, Collared Delma and Yakka Skink. Due to time and other logistical constraints, fauna survey methods such as spotlighting, camera trapping, other trapping, call playback and bat call detection were not generally undertaken within the scope of standard ecology surveys. Disturbance surveys Evidence of disturbance was routinely recorded during ecology surveys within the Project area. The type, severity and estimated time of most recent occurrence were recorded. This occurred either at the site where disturbance was noted (i.e. a disturbance site ) or where disturbance was more extensive, it was recorded within a disturbance area (Appendix 1 Figure 3). Typical disturbances recorded during ecology surveys included fire, broad-scale clearing (e.g. mechanical pulling), thinning (e.g. ringbarking/tordoning), logging, grazing, erosion and storm damage. The results of disturbance surveys were used to inform habitat and likelihood of occurrence assessments Pre-clearance Surveys Fauna breeding and shelter places Individual habitat features which may provide potential breeding and/or shelter sites for threatened fauna were recorded within disturbance footprints during pre-clearance surveys. Pre-clearance surveys follow a standard methodology for Origin-specific projects (Australia Pacific LNG 2014). Typically, the following features were recorded and described individually within the disturbance footprint (and nominated buffer) during pre-clearance surveys: Hollow-bearing trees (potential shelter/breeding site). Hollow-bearing logs (potential shelter site). Log piles (potential shelter/breeding site). Gilgais/melonholes (potential breeding site). Swamps/depressions (potential breeding site/foraging habitat). Important food trees (potential foraging site). Aerial and terrestrial termite mounds (potential shelter/breeding site). Rock piles/boulders (potential shelter/breeding site). Caves/deep crevices (potential shelter/breeding site). Ten pre-clearance surveys have been undertaken to date within the Project area. Collectively, these surveys have recorded over 2,200 individual habitat features - primarily logs/log piles and hollow-bearing trees but also including caves, gilgais, termitaria, trees/logs with decorticating bark and stags. Information from pre-clearance surveys is used to manage potential impacts on threatened fauna such as flagging off important habitat features (e.g. hollow-bearing trees, nests, habitat logs) prior to clearing Doc Ref: Q RP-1399 Revision: 1 Page 50

51 and flagging the need for fauna spotter catchers to be present when clearing of such features is unavoidable. Threatened flora searches Pre-clearance surveys typically included searches for threatened flora. Such searches were confined to the proposed project disturbance footprint. Target threatened species were identified using the results of desktop review and likelihood of occurrence assessments undertaken during preceding ecology surveys. To date, no threatened flora (commonwealth or state-listed threatened species) have been detected during any pre-clearance surveys undertaken within the Project area. Pre-clearance surveys have also included detailed descriptions of the component flora within each vegetation type present within the infrastructure disturbance footprint. Vegetation descriptions are based on the results of 100m x 5m transects. Although the primary purpose of the vegetation transects was to estimate the numbers and/or extent of plants protected under state legislation, searches for MNES flora have also been conducted within each transect Habitat Mapping Brigalow TEC Brigalow (Acacia harpophylla dominant and co-dominant) TEC is known to occur in the Project area covering 734ha, of which 326ha has been ground-truthed (Appendix 1 Figure 4). Brigalow TEC was identified and delineated within 10 of the 18 ecological surveys. The remaining 408ha was identified using state government mapped RE at a scale of 1: A conservative approach was taken to assess the extent of TEC i.e. where state-mapped REs indicated the presence of TEC-listed Brigalow communities the areas concerned were assumed to be TEC. No additional information concerning the extent of Brigalow TEC is available therefore no changes have been made to the extent of Brigalow TEC from the Referral. Patches of Brigalow that have been ground-truthed have been assessed against TEC condition criteria using the results of habitat quality assessments and disturbance surveys. Disturbances which may affect TEC status were recorded at vegetation assessment and disturbance sites/areas including fire, historical clearing, weed invasion and erosion. The presence of exotic grasses, particularly Buffel Grass Cenchrus ciliaris and Green Panic Megathyrsus maximus, was noted at several ground-truthed patches of TEC. As these pasture grasses have flourished within the highly disturbed Brigalow Belt, patches of Brigalow that do not have these grasses as a component within the ground layer are now rare. Assessment criteria (DoEE 2017a) concerning the presence and % cover of exotic grasses within Brigalow communities are not definitive; until further clarity is available patches of Brigalow with exotic grasses in the ground layer have been assessed on a case-by-case basis and where there is any doubt about TEC status the patch has been conservatively assessed as Brigalow TEC MNES Flora and Fauna Habitat for MNES flora and fauna has been updated based on the refinement of habitat definition and disturbance area calculations performed by ERM (2017) as well as review of all background data (Appendix 13). As originally compiled by ERM (2017), a list of all REs occurring in the Project area was derived from GIS intersection of Origin IRE (a combination of ground-truthed REs and DSITI (2017a) remnant and mature regrowth mapping) within the Project area. Habitat mapping rules for each species applied by ERM (2017) were reviewed and further modified (where possible). All RE associations for each species were checked and modified within habitat mapping rules as necessary. The findings of the ecology and preclearance surveys (e.g. likelihood of occurrence assessments and presence/absence of habitat features) were considered to derive the habitat mapping categories. Doc Ref: Q RP-1399 Revision: 1 Page 51

52 Refinement of species habitat mapping categories has resulted in definition of three broad categories: High Quality (HQ) Habitat, General Habitat (GH) and Low Quality (LQ) Habitat. The definitions for each habitat mapping category may vary according to individual species but in general terms the following broad definitions apply to their use in this assessment: HQ Habitat: - REs and/or areas that contain resources that are known or have high potential to be important for the maintenance of populations of the species. Such areas include roosting sites, shelter habitat and high quality foraging habitat. - Definition of high quality habitat is defined from known records (considering records which are both within and outside of tenement), expert advice/opinion, available literature/species profiles and field records. GH: - REs and/or areas that are considered to potentially support populations of the species but where there is insufficient knowledge to assess the areas as HQ or LQ Habitat. - Includes areas defined from known records or habitat that is considered to potentially support a species according to expert knowledge of habitat relationships. - This category also tends to be used for species which are habitat generalists or for species where little is known about specific habitat requirements. LQ Habitat: - These include remnant/regrowth REs or identified areas (e.g. clearings) that may contain some habitat resources for species that have been subject to previous disturbance or are REs that may contain some resources (e.g. food trees, hollow-bearing trees) but these are generally limited. - LQ Habitat may include REs for which there are no known association records or according to expert opinion/literature/known records they are less utilised than other REs. - Regrowth areas allocated to this category frequently contain no or fewer habitat resources (e.g. hollow-bearing trees and logs, mature trees) than their remnant counterparts. - Such areas e.g. regrowth may become future GH or HQ Habitat with appropriate management. Habitat for each MNES has been updated and is presented in Table 6 and shown in Appendix 1 Figures 5 to 14). Further details on distribution, survey guidelines/effort, known habitat use and habitat mapping rules for each species is presented in Appendix 13. Doc Ref: Q RP-1399 Revision: 1 Page 52

53 Table 6: Refinement of Habitat Mapping MNES Habitat Mapping Rule HQ Habitat GH LQ Habitat Bertya opponens Nil Remnant and regrowth , : Mapped habitat conforms to descriptions of RE associations for populations recorded within 20km of the Project area The species has not yet been detected within the Project area despite the presence of apparently suitable habitat REs Populations of the species are naturally patchy Nil Koala Remnant and mature regrowth of , , , , , , c, , : ERM (2017) identified REs on land zone 3 (i.e. alluvium) as the most likely to contain high quality food resources for Koala in the Project area. Both remnant and mature regrowth are included as Koala is known to feed on regrowth trees , , , , c, d, , , , a, : Other REs which may contain potential food trees are mapped as GH. Within the Project area typically these REs occur on sandstone ridges, plateaux and undulating low hills : RE is dominated by White Cypress Pine (Callitris glaucophylla); although this RE may contain eucalypts (e.g. E. populnea, E. melanophloia) these are typically associated species rather than being dominant or subdominant within the canopy. Typically RE occurs in coarse sand plains and low undulating hills with infertile soils. Northern Quoll Remnant , c, d, , , , a, : The identified REs occur on well-forested sandstone uplands and have the highest Remnant , , , , , , c, , , a, , , a, , , : Regrowth , , , , , , c, , , a, , , a, , , , Doc Ref: Q RP-1399 Revision: 1 Page 53

54 MNES Habitat Mapping Rule HQ Habitat GH LQ Habitat potential for presence of rock outcrops (i.e. potential denning sites). The identified REs may occur on low hills, valleys and alluvial flats surrounding the sandstone uplands and are considered to provide GH (i.e. foraging and dispersal habitat) for Northern Quoll c, d, , , , a, , : Regrowth vegetation has less likelihood of containing potential denning sites (rock outcrops, large logs) though it may represent foraging habitat. Greater Glider Remnant , , c, , c, d, , , , a: HQ Habitat typically includes taller and more dense eucalypt open forest and woodlands on sandstone uplands and riparian zones. These forest types typically contain large tree hollows (density varies according to past management) and preferred tree species (e.g. Corymbia citriodora, E. crebra, E. tereticornis, Angophora floribunda). Remnant , , , , , , , , , , : GH consists of drier and more open woodland REs that may adjoin higher quality habitat. Regrowth and <5 ha remnant , , , , , , c, , , , , , , c, d, , , , a, , : LQ Habitat includes regrowth of all RE types as regrowth is unlikely to support nest sites (tree hollows). Squatter Pigeon Remnant and regrowth , , , , , , c, , : The nominated REs are generally open woodland types containing suitable food and water resources. Remnant and regrowth a, , , , , c, d, , , , a, , : The nominated REs occur in drier landscapes where water (other than artificial sources) is typically less readily accessible Any mapped non-remnant vegetation: Clearings are mapped as LQ Habitat due to potential grazing pressures (loss of foraging and nesting resources) and frequent dominance of pasture by Buffel Grass (Cenchrus ciliaris) Doc Ref: Q RP-1399 Revision: 1 Page 54

55 MNES Habitat Mapping Rule HQ Habitat GH LQ Habitat Large-eared Pied Bat Remnant , c, d, , , a, , : Mapped HQ Habitat includes all areas of remnant vegetation likely to either contain or be within close proximity to suitable roost sites/habitat (e.g. caves, fissures, deep crevices). Remnant , c, , , , , a, , : Mapped GH includes all remnant vegetation of the nominated REs. Regrowth , c, , , , , a, , , , c, d, , , a, , : Regrowth may represent potential foraging habitat but is unlikely to contain suitable shelter sites. Southeastern Long-eared Bat Nil , c, , , , , a, , , , c, d, , , , a, , : All remnant and regrowth of the nominated REs are nominated as GH for the species. Regrowth is less likely to contain suitable shelter sites for the species however does provide foraging habitat for this species; regrowth is retained conservatively within GH until further research is undertaken on habitat preferences. Nil Doc Ref: Q RP-1399 Revision: 1 Page 55

56 MNES Habitat Mapping Rule HQ Habitat GH LQ Habitat Dunmall s Snake Nil , , , , , , c, , , a, , , , a, , a, , , , c, d, , , , a, , : All remnant and regrowth of the nominated REs are nominated as GH for the species. Regrowth is less likely to contain suitable shelter sites for the species however does provide foraging habitat for this species; regrowth is retained conservatively within GH until further research is undertaken on habitat preferences. Nil Collared Delma Remnant , , , , c, d, , , , a, , : HQ Habitat REs within the Project area are considered to include the nominated REs on land zones 3, 9 and 10. Remnant , , , c, , , a, , , , a, : REs on land zone 3 and 9 (other than those nominated as HQ Habitat) are conservatively mapped as GH. Information is currently lacking concerning use of these REs by the species. Regrowth , , , c, , , , , a, , , , a, , , , c, d, , , , a, , : LQ habitat is considered to be regrowth of all RE types in which the species may potentially be found. Doc Ref: Q RP-1399 Revision: 1 Page 56

57 MNES Habitat Mapping Rule HQ Habitat GH LQ Habitat Yakka Skink Remnant , , , : REs that contain/may contain suitable microhabitat features on Land Zones 3, 9 and 10 and Yakka Skink is known to have a strong association (Boobook 2017b). Remnant , , , , , , , , , c, d, , , , a: REs that contain/may contain suitable microhabitat features on Land Zones 3, 7, 9 and 10 but within REs which Yakka Skink is not known to have a strong association. Remnant & Regrowth , , a; Regrowth , , , , , , , , , , , c, d, , , , a, , : REs that generally lack suitable microhabitat features (e.g. lack of logs or suitable burrowing substrate), have unsuitable structural characteristics (e.g. tall forests, closed forests) or are floodprone REs. Doc Ref: Q RP-1399 Revision: 1 Page 57

58 Potential Impacts Potential impacts to threatened flora and fauna was originally provided in Attachment E of the original EPBC referral Spring Gully Matters of National Environmental Significance North-West and North-East Development Areas (ERM, 2017). The potential impacts has been updated based on the refined habitat mapping and is presented in Table 7. Due to the small area of habitat disturbed relative to available habitat and the mitigation measures outlined in Section 5.3, it is concluded that no significant impact is likely to occur for any EPBC Actlisted threatened species with the exception of the koala based on the EPBC Koala referral guidelines (DoE, 2014). Approximately 8ha of Brigalow TEC will be cleared to accommodate Project infrastructure which represents 1.1% of Brigalow TEC within the Project area. This is comprised of 2ha of ground-truthed Brigalow TEC and 6ha of potential TEC based on state mapped RE within the development footprint. The patches of TEC that will be impacted are no larger than 1.4ha with the majority being less than 0.1ha. Given the small percentage of community being cleared and the very small area of impact at each location, it is unlikely to be considered a significant impact. Further details on potential impacts is provided in Appendix 13. Table 7: Potential Impacts to Threatened Flora and Fauna Threatened Flora and Fauna Habitat within Project area (ha) Habitat within Proposed Disturbance Footprint (ha) HQ GH LQ Total HQ GH LQ Total Bertya opponens - 15,021-15, (1.5%) Koala 1,995 15, , (0.9%) 235 (1.5%) 9 (1.4%) 263 Northern Quoll 15,271 2, , (1.5%) 27 (1 %) 4 (0.8%) 263 Greater Glider 15,385 2, , (1.5%) 27 (1.3%) 11 (1.5%) 263 Squatter Pigeon 1,995 16,149 19,915 38, (0.9%) 245 (1.5%) 329 (1.6%) 593 Large-eared Pied Bat 15,890 1, , (1.5%) 8 (0.7%) 6 (1.3%) 256 Southeastern Long-eared Bat - 17,499-17, (1.5%) Dunmall s Snake - 19,041-19, (1.4%) Doc Ref: Q RP-1399 Revision: 1 Page 58

59 Threatened Flora and Fauna Habitat within Project area (ha) Habitat within Proposed Disturbance Footprint (ha) HQ GH LQ Total HQ GH LQ Total Collared Delma 17, , (1.4%) 15 (1.5%) 8 (1.2%) 271 Yakka Skink 1,724 15, , (1.1%) 238 (1.5%) 9 (0.9%) Significant Impact Assessment The Matters of National Environmental Significance Significant Impact Guidelines 1.1 (DoEE 2013a) has been used to guide the assessment of the Project s impact significance on terrestrial threatened species and ecological community. Assessments of significance against the guideline criteria for each threatened species is provided in Appendix 13 with a summary of the results provided in Table 8. Doc Ref: Q RP-1399 Revision: 1 Page 59

60 Table 8: Assessment of Impacts to Terrestrial Threatened Species MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines Bertya opponens Koala Direct Impacts: Although the Project area provides potential habitat for the species, B. opponens has not been detected. All mapped potential habitat (15,0121ha) is regarded as GH. No further refinement to mapping can be made unless populations are detected. Populations of this species are naturally patchy and given that the species has not yet been detected despite multiple surveys in apparently suitable habitat the development footprint is unlikely to support an important population of the species. Area of GH within the development footprint represents about 1.5% of available habitat within the Project area. As such it is unlikely that there will be a significant impact on the species from the proposed development. Indirect Impacts: none known. If populations are detected, dust during construction or from traffic could potentially impact upon populations beside or close to roads or other linear corridors. There is also some potential for further spread of weeds which may invade habitat along linear clearings. Introduction of disease through construction is unlikely to be of relevance to this species. Direct Impacts: The proposed development will remove approximately 19ha of HQ Habitat, 235ha of GH and 9ha of LQ Habitat. For the proposed development, the disturbance area represents 0.9% of HQ Habitat, 1.5% of GH and 1.4% of LQ Habitat. Overall, this equates to removal of 1.4% of all available habitat within the Project area. There are no significant impact guidelines available for B. opponens. The EPBC Act significant impact guidelines (DoE 2013) for vulnerable species refer to impacts to important populations of the species. Important population is defined as a population that is necessary for a species longterm survival and recovery. This may include populations identified as such in recovery plans, and/or that are key source populations either for breeding or dispersal; populations that are necessary for maintaining genetic diversity; and/or populations that are near the limit of the species range. It is difficult to confidently determine if there is an important population occurring within the Project area due to a lack of data; however the species has not yet been detected during any of the ecology and preclearance surveys. Considerable areas of known habitat occur outside of the Project area in the rugged sandstone uplands to the north and northeast of NWDA and NEDA. No significant impact Based on the Koala referral guidelines (DoE 2014), the loss of 20ha or more of high quality habitat critical to the survival of Koala (i.e. habitat score of 8) is likely to have a significant impact on Koalas for the purposes of the EPBC Act. Habitat within the Project area received a habitat score of 8. Clearing will largely avoid important riparian vegetation, and incorporate a suite of management measures to minimise potential impacts. Although Doc Ref: Q RP-1399 Revision: 1 Page 60

61 MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines Indirect Impacts: The level of fragmentation caused by the development is minor and the general linear nature of the vegetation removal, avoidance of important riparian vegetation communities, implementation of management measures and limited potential for increasing threatening processes (such as increased traffic), the long-term impact to koalas is reduced. these measures will assist in managing impacts the area of disturbance to habitat critical to the survival of the Koala is substantial and as such a significant impact may occur (although residual significant impact is likely to be restricted to the 19ha of preferred habitat (= HQ Habitat). Within the regional context, clearing within the Project area and surrounding landscape has targeted areas with the most fertile soils including HQ Koala Habitat (e.g. REs , , , ). Major watercourses such as Eurombah and Scott Creeks are likely to be used as dispersal corridors within the region. Considerable areas of GH are available and will remain intact within the sandstone uplands that are extensive and contiguous with areas to the north and east of NWDA and west and north of NEDA. Significant impact likely Northern Quoll Direct Impacts: The proposed development will remove approximately 232ha of HQ Habitat, 27ha GH and 4ha of LQ Habitat. The proposed development is unlikely to have a significant impact given the amount of HQ habitat likely to be disturbed is 1.5% relative to available HQ habitat in the Project area. Clearing will preferentially avoid potential denning sites such as rocky areas. Indirect Impacts: Risk of vehicle strike with Northern Quoll is considered low due to low levels of traffic, traffic operational periods and low vehicle speeds. There is potential for individuals to be at greater risk of predation by cats and wild dogs if they are required to move through cleared areas (e.g. new roads). Northern Quolls are highly mobile and it is The Impact Assessment Guidelines for Northern Quoll (DoE, 2016) define a high risk of significant impact as actions which remove known foraging and dispersal habitat in toad invaded areas and a significant population as presumed to occur in any area with recent evidence of a single northern quoll. The Project area contains Cane Toads. Evidence of a Northern Quoll is considered recent if it is post 1980 and may include, but is not limited to, a database record, scat/ latrine site, hair sample, remote camera detection or a trapped or sighted animal by a qualified practitioner (DSEWPAC 2011). No confirmed Northern Quoll sightings are known from the Project area. Therefore there is uncertainty as to whether the development footprint contains foraging and/or dispersal habitat for the species (i.e. it is uncertain whether the species exists in the Project area). For the purposes of this assessment It has been conservatively assumed that a Northern Quoll population is likely to occur in the Project area. However, the proposed development is unlikely to have a significant impact given the small amount Doc Ref: Q RP-1399 Revision: 1 Page 61

62 MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines unlikely that clearing (i.e. linear strips and up to 100m x 150m wells) will fragment any existing populations. of habitat disturbed relative to available habitat in the surrounding landscape. Other available habitat in the regional context includes extensive areas of rugged sandstone uplands (e.g. Expedition Range) that are contiguous with the northern end of NEDA. No significant impact Greater Glider Direct Impacts: The proposed development will remove approximately 225ha of HQ Habitat, 27ha of GH and 11ha of LQ Habitat. This is approximately 1.5% of available HQ habitat for this species within the Project area. Based on currently available information on the distribution and abundance of the species in the Project area, and given that the disturbance is linear in nature, and constitutes only 1.5% of available habitat, the Project is unlikely to lead to a significant impact on the species. Indirect Impacts: Risk of vehicle strikes are considered low due to low levels of traffic, traffic operational periods and low vehicle speeds. The scale of clearing proposed (1.5% of available HQ Habitat) is unlikely to further fragment and reduce the size of any important population. Noise disturbance from construction is likely to be of short duration. Increased risk of harm from predators such as cats and wild dogs is unlikely to be further increased. Some increased risk of entanglement may occur where disturbed areas (e.g. wells) are fenced with barbed-wire. There are no significant impact guidelines available for Greater Glider. The EPBC Act significant impact guidelines (DoE 2013) for vulnerable species refer to impacts to important populations of the species. Important population is defined as a population that is necessary for a species longterm survival and recovery. This may include populations identified as such in recovery plans, and/or that are key source populations either for breeding or dispersal; populations that are necessary for maintaining genetic diversity; and/or populations that are near the limit of the species range. It is difficult to confidently determine if there is an important population occurring within the Project area due to a lack of data, but in consideration of the precautionary principal, it is assumed that an important population does occur. The mostly cleared, grazing land within the Project area (constituting approximately half of the Project area) is not suitable habitat for this species. Almost of all of the sandstone uplands and some riparian corridors represent HQ habitat for the species. Other available habitat in the regional context includes extensive areas of rugged sandstone uplands (e.g. Expedition Range) that are contiguous with the northern end of NEDA. No significant impact Doc Ref: Q RP-1399 Revision: 1 Page 62

63 MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines Squatter Pigeon Large-eared Pied Bat Direct Impacts: The proposed development will remove approximately 19ha of HQ Habitat, 245ha of GH and 329ha of LQ Habitat. This is approximately 0.9% of available HQ habitat for this species within the Project Area and is not of an extent that is likely to lead to a decline in the species, or negatively impact an important population and therefore the proposed development is unlikely to lead to a significant impact on the squatter pigeon. Indirect Impacts: Risk of vehicle strikes are considered low due to low levels of traffic and low vehicle speeds. The scale of clearing proposed (0.9% of available HQ Habitat) is unlikely to further fragment and reduce the size of any important population most records are from existing cleared areas. Noise disturbance from construction is likely to be of short duration. Increased risk of harm from predators such as cats and wild dogs is unlikely to be further increased. There is some potential for further spread of weeds along linear clearings. Direct Impacts: The proposed development will remove approximately 242ha of HQ Habitat, 8ha of GH and 6ha of LQ Habitat. This is approximately 1.5% of potentially available HQ habitat within the Project area. The development footprint avoids cliff lines which have the highest chance of potential roost sites. Habitat outside the development footprint will not be modified and therefore it is unlikely that There are no significant impact guidelines available for Squatter Pigeon. The EPBC Act significant impact guidelines (DoE 2013) for vulnerable species refer to impacts to important populations of the species. Important population is defined as a population that is necessary for a species longterm survival and recovery. This may include populations identified as such in recovery plans, and/or that are key source populations either for breeding or dispersal; populations that are necessary for maintaining genetic diversity; and/or populations that are near the limit of the species range. It is difficult to confidently determine if there is an important population occurring within the Project area due to a lack of data, but in consideration of the precautionary principal, it is assumed that an important population does occur. Squatter Pigeon occurs throughout the broader SGRA and the scale of development is unlikely to significantly impact upon the species. Although populations have declined and are rare to the south of NEDA/NWDA, extensive areas of habitat containing significant populations occur within the sandstone belt to the immediate north of the Project area. No significant impact There are no significant impact guidelines available for Large-eared Pied Bat. The EPBC Act significant impact guidelines (DoE 2013) for vulnerable species refer to impacts to important populations of the species. Important population is defined as a population that is necessary for a species long-term survival and recovery. This may include populations identified as such in recovery plans, and/or that are key source populations either for breeding or dispersal; populations that are necessary for Doc Ref: Q RP-1399 Revision: 1 Page 63

64 MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines the proposed development will lead to a significant impact on the species. Indirect Impacts: Given that this species is highly mobile the proposed clearing is not considered to represent a barrier to movement. Noise disturbance from construction is likely to be of short duration. Increased risk of harm from predators such as cats and wild dogs is unlikely to be further increased. Some increased risk of entanglement may occur where disturbance areas are fenced with barbed-wire. maintaining genetic diversity; and/or populations that are near the limit of the species range. It is difficult to confidently determine if there is an important population occurring within the Project area due to a lack of data, but in consideration of the precautionary principal, it is assumed that an important population does occur. Large-eared Pied Bat is likely to occur throughout the broader SGRA and the scale of development is unlikely to significantly impact upon the species. Potential roost sites are likely to be avoided. Extensive areas of habitat containing known populations of the species occur within the sandstone belt to the immediate north and northeast of the Project area (e.g. Expedition Range). No significant impact South-eastern Long-eared Bat Direct Impacts: The proposed development will remove approximately 256ha of GH. This is less than 1.5% of available habitat for the species within the Project area and is not of an extent that is likely to lead to a decline in the species (ERM 2017). Some loss of potential roost sites (e.g. hollowbearing trees) is likely to occur however some of these can be preferentially avoided. Habitat outside the development footprint will not be modified and therefore it is unlikely that the proposed development will lead to a significant impact on the species. Indirect Impacts: Given that this species is highly mobile the proposed clearing is not considered to represent a barrier to movement. Noise disturbance from construction is likely to be of short duration. Increased risk of harm from predators such There are no significant impact guidelines available for South-eastern Longeared Bat. The EPBC Act significant impact guidelines (DoE 2013) for vulnerable species refer to impacts to important populations of the species. Important population is defined as a population that is necessary for a species long-term survival and recovery. This may include populations identified as such in recovery plans, and/or that are key source populations either for breeding or dispersal; populations that are necessary for maintaining genetic diversity; and/or populations that are near the limit of the species range. It is difficult to confidently determine if there is an important population occurring within the Project area due to a lack of data, but in consideration of the precautionary principal, it is assumed that an important population does occur. Doc Ref: Q RP-1399 Revision: 1 Page 64

65 MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines as cats and wild dogs is unlikely to be further increased. Some increased risk of entanglement may occur where disturbance areas are fenced with barbed-wire. South-eastern Long-eared Bat is likely to occur throughout the broader SGRA and the scale of development is unlikely to significantly impact upon the species. Extensive areas of potential habitat occur within the sandstone belt to the immediate north and northeast of the Project area (e.g. Expedition Range). No significant impact Dunmall s Snake Direct Impacts: The proposed development will remove approximately 271ha of GH. While large patches of contiguous, suitable habitat do occur within the Project area, approximately 1.4% of available habitat will be cleared from within the development footprint. While no records of the species are known within the Project area, the intensity of the survey is considered insufficient to confirm absence of any colonies or important populations. Indirect Impacts: The proposed development does not represent a barrier to dispersal throughout the landscape. Vegetation clearing is generally confined to linear corridors, providing minimal fragmentation or barriers to the movement/dispersal of this species and is therefore unlikely to lead to a significant impact on Dunmall's Snake. It is difficult to confidently determine if there is an important population of this species occurring within the Project area due to a lack of data, but in consideration of the precautionary principal, it is assumed that an important population does occur. DSEWPaC (2011b) states that clearing of four or more hectares of important habitat has a high risk of causing a significant impact. Although GH has been mapped for this species within the Project area its presence within these areas has not been established and due to the patchiness of populations it is unlikely that all GH would be occupied. The eastern and north-eastern parts of NWDA and the northern half of NEDA have good connectivity with large vegetated tracts in the surrounding landscape. In particular, vegetation within NEDA is linked to a vast area of rugged sandstone uplands vegetated by potentially suitable eucalypt woodlands and open forests. Much of this contiguous habitat is protected within Expedition (Limited Depth) National Park and several state forests. No significant impact Collared Delma Direct Impacts: The proposed development will remove approximately 248ha of HQ Habitat, 15ha of GH and 8ha of LQ Habitat. While no records of the species are known within the Project area, the intensity of the survey is considered It is difficult to confidently determine if there is an important population of this species occurring within the Project area due to a lack of data, but in Doc Ref: Q RP-1399 Revision: 1 Page 65

66 MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines Yakka Skink insufficient to confirm absence of any colonies or important populations. While large patches of contiguous, suitable habitat do occur within the Project area, less than 1.4% of HQ habitat will be cleared from within the development footprint. Indirect Impacts: Vegetation clearing is generally confined to linear corridors; given that this species has high site fidelity there is some potential for linear clearings to cause fragmentation of populations and form barriers to the movement/dispersal of this species. It appears that this species is sensitive to grazing (DSEWPaC 2011c) clearings for the Project may promote easier access to some sites by livestock. Disturbances from clearing may also potentially lead to an increase in the spread of exotic grasses which may change habitat suitability, promote further grazing and change fire regimes. Direct Impacts: The proposed development will remove approximately 19ha of HQ Habitat, 238ha of GH and 9ha of LQ Habitat. While no records of the species are known within the Project area, the intensity of the survey is considered insufficient to confirm absence of any colonies or important populations. The proposed development is unlikely to represent a barrier to dispersal throughout the landscape (ERM 2017). While large patches of contiguous, suitable habitat do occur within the Project area, less than 1.1% of HQ habitat will be cleared from within the development footprint. consideration of the precautionary principal, it is assumed that an important population does occur. DSEWPaC (2011b) states that clearing of two or more hectares of important habitat has a high-risk causing a significant impact. Although GH and HQ Habitat have been mapped for this species within the Project area its presence within these areas has not been established; it is unlikely that all GH and HQ Habitat would be occupied by the species. The eastern and north-eastern parts of NWDA and the northern half of NEDA have good connectivity with large vegetated tracts in the surrounding landscape. In particular, vegetation within NEDA is linked to a vast area of rugged sandstone uplands vegetated by potentially suitable eucalypt woodlands and open forests. Much of this contiguous habitat is protected within Expedition (Limited Depth) National Park and several state forests. No significant impact It is difficult to confidently determine if there is an important population of this species occurring within the Project area due to a lack of data, but in consideration of the precautionary principal, it is assumed that an important population does occur. DSEWPaC (2011b) states that removal of any microhabitat features within 200m of a colony has a high-risk of causing significant impact on the species. Although HQ Habitat has been mapped for this species within the Project area its presence within these areas has not been established; due to the patchiness of populations it is unlikely that all HQ Habitat would be occupied by the species. Doc Ref: Q RP-1399 Revision: 1 Page 66

67 MNES Potential Impact Summary Impacts within Regional Context/Assessment Against DoEE Guidelines Indirect Impacts: Vegetation clearing is generally confined to linear corridors, providing minimal fragmentation or barriers to the movement/dispersal of this species and is therefore unlikely to lead to a significant impact on Yakka Skink. No information is available concerning other populations within SGRA and few other populations are known surrounding the Project area. Use of the extensive sandstone uplands to the north of the Project area is probably unlikely. Hence, significant habitat for the species in the broader landscape is not currently known and impacts cannot be assessed within the regional context. No significant impact Doc Ref: Q RP-1399 Revision: 1 Page 67

68 5.3. Management Measures The management of threatened species and ecological community will be undertaken in accordance with the Spring Gully Field Environmental Constraints Planning and Field Development Protocol (Q MP-1157) (Appendix 7) and the Threatened Species and Ecological Community Management Plan (Q MP-1158) (Appendix 15). Table 9 provides a summary of the management measures as detailed in the Threatened Species and Ecological Community Management Plan that will be implemented to avoid, minimise and mitigate potential impacts to MNES during the various phases of the Project. Constraints mapping has been developed by Biodiversity Assessment and Management Pty Ltd Ecological Consultants to categorise environmental sensitivity in the Project area (refer to Appendix 1 Figure 15). Table 10 describes the category, description of the category and the category constraint which will influence infrastructure design and placement. The percentages in Table 10 have been derived from the ecology data captured to date and state data to assist in describing the categories. These percentages may change in future as further ecology surveys are conducted. The constraints mapping methodology is discussed in detail in the Spring Gully Field Environmental Constraints Planning and Field Development Protocol (Q MP-1157) (Appendix 7). Table 9: Management Practices for Threatened Species and Ecological Communities Project phase Activity Management Practices Development Infrastructure planning All infrastructure planning will be conducted in accordance with the Spring Gully Constraint and Field Planning Protocol. However, the following provides a summary of management practices that will be implemented to manage potential impacts to MNES identified within this plan: The Australia Pacific LNG GIS will be consulted during the desktop stage of infrastructure planning to determine the presence of environment values (such as remnant and regrowth REs, TECs, threatened species habitat, watercourses and wetlands). Field assessment verification (through ecological surveys) will be conducted to verify the presence of threatened species, determine species habitat and ecological communities. Ecology surveys will be undertaken in accordance with the Spring Gully Constraint and Field Planning Protocol. The likelihood of occurrence of threatened species will also be assessed. Results from the field assessment will inform infrastructure planning. Infrastructure will be sited to avoid and/or minimise impacts to environmental values, with priority to avoid adverse impacts to threatened species and ecological communities, wherever possible. As such, infrastructure will be sited to avoid areas of higher ecological value (i.e. high or general species habitat or TEC) and in cleared land and adjacent to existing disturbance, where possible. No surface infrastructure will be sited within 100m of the Scott Creek spring Clearing A pre-clearing inspection will be undertaken by a qualified fauna spotter catcher (holds a valid rehabilitation permit (spotter/catcher endorsed)). A qualified fauna spotter catcher will also be made available during clearing activities. Clearing will be carried out in a sequential manner and in a way that directs escaping wildlife away from clearing and into adjacent native vegetation or natural areas and not cross roads or into other areas of threat. Doc Ref: Q RP-1399 Revision: 1 Page 68

69 Project phase Activity Management Practices Where White-throated Snapping Turtle habitat has been identified along Eurombah Creek and crossing are required, clearing will only be undertaken between January and April (inclusive) so as to avoid the nesting, incubation and hatching period unless surveys by a suitably qualified person determine that the construction area will not intersect active nesting sites. As soon as practicable after capturing, fauna is assessed for signs of illness or injuries and determination is made by the fauna spotter catcher if the animal is fit for relocation or should be taken to a veterinarian clinic, wildlife carer or should be put down by emergency euthanasia. Fauna handling and relocation procedures will be undertaken by the Fauna Spotter Catcher in accordance with the conditions of the permit issued under the Nature Conservation Act Any animal captured under the permit will be returned to the nearest appropriate habitat (or in accordance with the relevant permit holders conditions), unless the animal is sick, injured or orphaned. This process will be undertaken in accordance with the Code of Practice Care of Sick, Injured of Orphaned Protected Animals in Queensland (EHP 2013). Habitat features for threatened species, as identified by a suitably qualified person will be salvaged and relocated outside the clearing area, prior to clearing, where possible to minimise habitat loss. Where possible, when erecting any Project related fencing the use of barb wire particularly on the top strand, is to be avoided to prevent threatened species (particularly Greater Glider and Micro-bats) from becoming entangled. Fauna friendly fencing must be used, whilst being in accordance with landowner and/or structural requirements. Construction impacts will be managed in accordance with the Construction Environmental Management Plan or equivalent contractor environment management plan/system Clearing will not be undertaken by burning of woody debris, in order to limit loss of microhabitat. Progressive rehabilitation will be conducted in accordance with the Spring Gully EA conditions. Fire management Collision Management The following controls will be implemented to minimise the risk of fire: No burning of cleared vegetation will be undertaken. Fire extinguishers will be present at the location of hot works (primarily welding). Hot works permits will be followed at all times where applicable. Site vehicles will be equipped with fire extinguishers. Flammable material will not be stockpiled or stored near hot work activities (including vegetation stockpiles). Smoking areas will be designated with provision for containers for safe disposal of cigarette butts. A speed limit of 40km/hr will be enforced in construction sites to minimise risks of mortality to fauna by vehicle collision. The implementation of speed limits is a recommendation mitigation measure for mitigating impacts of direct injury or Doc Ref: Q RP-1399 Revision: 1 Page 69

70 Project phase Activity Management Practices death of Koala (NRMMC 2009). Implementing this mitigation throughout construction sites will likely reduce the risk to other threatened species, which may potentially bask on access tracks (Dunmall s Snake and Yakka Skink) or forage along access tracks (Squatter Pigeon). Weed Management Weed management will be conducted in accordance with the Biosecurity Act Weed species will be managed in accordance with the Biosecurity Management Plan for the Project to minimise degradation from weeds to vegetation values. Dust suppression Dust suppression activities should be undertaken in accordance with the Project s Construction Environmental Management Plan or equivalent contractor environment management plan/system. Operation Pest Management Weed and pest species will be managed in accordance with the Biosecurity Management Plan for the Project to minimise degradation from weeds to vegetation values. Fire management The following controls will be implemented to minimise the risk of fire: No burning of cleared vegetation will be undertaken. Fire extinguishers will be present at the location of hot works (primarily welding). Hot works permits will be followed at all times where applicable. Site vehicles will be equipped with fire extinguishers. Flammable material will not be stockpiled or stored near hot work activities (including vegetation stockpiles). Smoking areas will be designated with provision for containers for safe disposal of cigarette butts. Dust suppression Dust suppression activities should be undertaken in accordance with contractor environment management plan/system. Decommissioning Rehabilitation Rehabilitation will be conducted in accordance with the relevant conditions of the Spring Gully EA and/or the approved Remediation, Rehabilitation, Recovery Monitoring Program. Pest management Implement Biosecurity Management Plan through the Decommissioning Environmental Management Plan for the Project. Table 10: Constraints Category Category Constraint Factors Constraint Category 1 98% of the habitat patches within this category possess biodiversity characteristics that are unique and threatened at a National level (i.e. they either represent or may support threatened ecological communities) and all are threatened (i.e. have a biodiversity status of endangered or of concern ) at the bioregional level. 46% of these patches contain very high habitat values for EPBC Act listed threatened flora and fauna (achieving a score of out of a possible 20). All patches in this category are over 5 ha in area, with 80% having very high Siting of infrastructure within Category 1 will be avoided where practical. Where wells and linear infrastructure cannot avoid Category 1 as a result of other constraints, the siting of infrastructure will take into Doc Ref: Q RP-1399 Revision: 1 Page 70

71 Category Constraint Factors Constraint Category values for tract size, and are likely to be in good condition due to minimal intrusion of edge effects. The habitat model indicates that the biodiversity values of these patches are likely to be extremely sensitive to the impacts of clearing and fragmentation, subject to confirmation through ground-truthing. account the written advice of a suitably qualified ecologist. All other infrastructure will be sited to avoid Category % of habitat patches within this category possess biodiversity characteristics that are unique and threatened at a National level (i.e. they either represent or may support threatened ecological communities) and 62% are threatened (i.e. have a biodiversity status of endangered or of concern ) at the bioregional level. 54% of these patches contain very high (score of 18-20) or high (score of 15-17) habitat values for EPBC Act listed threatened flora and fauna and 64% have very high or high values for tract size. The habitat model indicates that the biodiversity values of these patches are likely to be highly sensitive to the impacts of clearing and fragmentation, subject to confirmation through ground-truthing. 3 None of the patches within this category represent or may support threatened ecological communities and 17% are threatened (i.e. have a biodiversity status of endangered or of concern ) at the bioregional level. 83% of these patches are not threatened at the bioregional level (i.e. have a not of concern biodiversity status) and 47% have very high (score of 18-20) or high (score of 15-17) habitat values for EPBC Act listed threatened flora and fauna. 37% have very high or high values for tract size, therefore the majority of patches (63%) are likely to be smaller in size, with some level of intrusion by edge effects. Biodiversity characteristics of these habitat patches are mostly well-represented within the bioregion and are mostly unique at a sub-regional level. The habitat model indicates that the biodiversity values of these patches are likely to be sensitive to the impacts of clearing and fragmentation, subject to confirmation through ground-truthing. 4 None of the patches within this category represent or may support threatened ecological communities or have high (score of 18-20) or very high (score of 15-17) habitat values for EPBC Act listed flora and fauna. The majority of these patches are regrowth vegetation of types that are threatened in the bioregion. 29% have very high or high values for tract size, therefore the majority of patches (71%) are likely to be smaller in size, with some level of intrusion by edge effects. The habitat model indicates that the biodiversity values of these patches are less likely to be sensitive to the impacts of clearing and fragmentation due to their regrowth status and condition, subject to confirmation through ground-truthing. Siting of infrastructure within Category 2 will be avoided where practical. Where the location cannot be avoided as a result of other constraints, infrastructure will be sited near cleared areas or areas of lower ecological condition. Where this cannot be achieved, the siting of infrastructure will take into account the written advice of a suitably qualified ecologist. Siting of infrastructure within Category 3 will be avoided where practical. Where the location cannot be avoided as a result of other constraints, infrastructure will be sited near cleared areas or areas of lower ecological condition. Where this cannot be achieved, the siting of infrastructure will take into account the written advice of a suitably qualified ecologist. Siting of infrastructure within Category 4 will be avoided where practical. Where the location cannot be avoided as a result of other constraints, infrastructure will be sited near cleared areas or areas of lower ecological condition. Where this cannot be achieved, the siting of infrastructure will take into account the written advice of a suitably qualified ecologist. Doc Ref: Q RP-1399 Revision: 1 Page 71

72 Category Constraint Factors Constraint Category 5 None of the patches within this category represent or may support threatened ecological communities or have high (score of 18-20) or very high (score of 15-17) habitat values for EPBC Act listed flora and fauna. Biodiversity values within this category are generally common within the bioregion. Patches are isolated from other remnant vegetation or likely to be in poor condition due to edge effects. Most species within these patches are either increaser species that proliferate in agroecosystems or unable to persist in the long-term as resources in the patch degrade. The habitat model indicates that the biodiversity values of these patches are not sensitive to the impacts of clearing and fragmentation. Infrastructure will be preferentially sited in this Category 6 Cleared areas Infrastructure will be preferentially sited in this Category Doc Ref: Q RP-1399 Revision: 1 Page 72

73 6. Groundwater 6.1. Introduction The Project is located within the Surat Cumulative Management Area (CMA). Potential impacts associated with petroleum activities in a CMA are assessed and managed by the Queensland Office of Groundwater Impact Assessment (OGIA formerly the Queensland Water Commission (QWC)), which is required to develop an Underground Water Impact Report (UWIR) for the CMA. The UWIR includes the preparation of a regional scale numerical flow model to assess impacts to bores and springs. Based on the risks to those receptors, monitoring and mitigation (e.g. make good) requirements are assigned to responsible tenure holders. The initial UWIR for the Surat CMA was first published in 2012 (QWC, 2012) and recently revised in The conceptual hydrogeological model and numerical modelling undertaken for the Surat CMA is described in detail therein (OGIA, 2016a, 2016b, 2016c). The 2016 report did not include the Project, but did include existing CSG production, contiguous to the Project. A groundwater impact assessment was prepared for the original Referral which was provided to the IESC for their assessment. To address the IESC advice, a revised impact assessment has been completed and is provided in Appendix 14. A summary of the assessment is provided below Hydrogeological Conceptualisation The Project is situated within geographical extent of the Surat Basin which forms part of the Great Artesian Basin (GAB). The GAB comprises of a number of regional-scale aquifers and confining aquitards with the aquifers being a significant source of water used for stock, public, and domestic supply. The Bowen Basin underlies the Surat Basin in the Project area and the Bandanna Formation within the Bowen Basin is the target gas bearing formation for the Project. The formations of importance to this assessment are the Hutton Sandstone, the Boxvale Sandstone Member, the Precipice Sandstone and Bandanna Formation. The Triassic-aged Moolayember and Clematis Sandstone are not present across the Project. The Hutton Sandstone along with deeper members of the Injune Creek Group (i.e. Eurombah Formation, Walloon Coal Measures, Springbok Sandstone, Westbourne Formation) is the upper most unit present within the Project area. The Precipice Sandstone is the oldest unit within the Surat Basin and unconformably overlies Permian units of the Bowen Basin in the Project area. The Precipice Sandstone is overlain by the Evergreen Formation, an aquitard which separates the Precipice Sandstone from the Hutton Sandstone and other major aquifers of the GAB. The Boxvale Sandstone member, a sub unit of the Evergreen Formation is not laterally continuous, but is present in the Project area. Sequences within the Bowen Basin that unconformably underlie the Precipice Sandstone in the Project area include the Rewan Group and Bandanna Formation. Generally, the Bandanna Formation is isolated from the overlying Precipice Sandstone aquifer by the Rewan Formation, an aquitard. However, located to the east of Injune along the western extent of the NWDA, a north-south trending zone exists where the Rewan Formation has been eroded away. As a result, the Precipice Sandstone unconformably overlies the Bandanna Formation across this zone, increasing the potential for interaction between the two formations in this area. The contact area between the Precipice Sandstone and the Bandanna Formation is referred to as the Bandanna Formation sub-crop. To the east of the sub-crop, underlying the remainder of the NWDA and the NEDA, the Bandanna Formation is stratigraphically separated from the overlying Precipice Sandstone by the very low permeability mudstones of the Rewan Formation. The next major aquifer above the Precipice Sandstone is the Hutton Sandstone, however, these aquifers are separated by the thick Evergreen Formation aquitard, which is known to be an effective seal (QWC, 2012). This is confirmed by Australia Pacific LNG monitoring data, which shows multiple lines of evidence of limited potential for Doc Ref: Q RP-1399 Revision: 1 Page 73

74 hydraulic connection between the formations, including: significant vertical head gradients, differing water level trends and significantly different groundwater chemistries between the aquifers across the Project area (APLNG, 2017). Pressure reduction due to Bandanna Formation depressurisation is therefore unlikely to propagate through the Precipice Sandstone and affect the Hutton Sandstone (QWC, 2012). Figure 8 presents the regional hydrostratigraphy as presented in the 2016 UWIR (OGIA, 2016a) and a regional cross section (west-east) has been produced from OGIA (2016a) geological model surfaces and is presented in Figure 9. Doc Ref: Q RP-1399 Revision: 1 Page 74

75 Figure 8: Regional Hydrostratigraphy (sourced from OGIA, 2016a) Doc Ref: Q RP-1399 Revision: 1 Page 75

76 Figure 9: Geological Cross Section through NEDA and NWDA (Data source OGIA Geological Model, 2016a) 6.3. Groundwater Levels CSG production in the Bandanna Formation commenced in 1996 with the development of Fairview by Santos, expanding in 2005 with the commencement of the Australia Pacific Spring Gully CSG Project. Groundwater levels have been monitored by Australia Pacific LNG in the Precipice Sandstone since 2007, the Hutton Sandstone and the Bandanna Formation since approximately The results indicate: Pressures in the Bandanna Formation are generally declining due to existing production from the existing Spring Gully CSG Project. Pressure reductions of over 300m have been experienced in the Spring Gully area. Groundwater elevations are approximately 150mAHD in the vicinity of the NWDA and 260mAHD in the NEDA. Water levels in the Precipice Sandstone are all increasing following the commence of injection at Reedy Creek in early Prior to this time, water levels were either declining or stable. Groundwater levels were likely to be declining as a result of groundwater abstraction from third party groundwater bore sourcing groundwater from the Precipice Sandstone The groundwater elevation in the Precipice Sandstone is between 270mAHD and 290mAHD across the Spring Gully area. Only one hydrograph is available for the Evergreen Formation, with the bore located in outcrop and near a creek. This bore has a relatively flat water level at approximately 254mAHD, with peaks and recessions that can be strongly correlated with rainfall events. The Hutton Sandstone groundwater elevations range from approximately 230mAHD to 300mAHD. Hydrographs indicate declining trends across most of the Hutton Sandstone bores. This declining groundwater level trend is likely a function of CSG production from the Walloon Coal Measures impacting on the underlying Hutton Sandstone Groundwater Quality Groundwater quality is monitored by Australia Pacific LNG from dedicated monitoring bores and landholder bores in the Hutton Sandstone, Precipice Sandstone and CSG production wells from the Doc Ref: Q RP-1399 Revision: 1 Page 76

77 Bandanna Formation. A statistical summary of the monitoring results for the Spring Gully area are presented in Table 11. Groundwater in the Hutton Sandstone and Precipice Sandstone are predominantly sodium-bicarbonate type waters and groundwater extracted from the Bandanna Formation is more dominated by sodium chloride type waters. There is order of magnitude differences in salinity between the Hutton Sandstone (more saline) and Precipice Sandstone, and Precipice Sandstone and Bandanna Formation (more saline). Figure 10 provides a schematic comparison of physiochemical parameters in a stratigraphic sense. Doc Ref: Q RP-1399 Revision: 1 Page 77

78 Table 11: Summary of Hutton Sandstone, Bandanna Formation and Precipice Sandstone Water Quality Hutton Sandstone Precipice Sandstone Bandanna Formation Parameter Units Count Min Max Average Count Min Max Average Count Min Max Average General Water Quality Indicators Electrical Conductivity (Field) µs/cm , , , ,000 9, Total Dissolved Solids mg/l , ,700 5, ph (Field) ph_units , Major Cations and Anions Calcium mg/l Magnesium mg/l Sodium mg/l , , Potassium mg/l Chloride mg/l , , Alkalinity (Total) as CaCO3 mg/l , Sulphate as SO4 mg/l Fluoride mg/l Metals and Other Parameters Aluminium mg/l Antimony mg/l Arsenic mg/l Barium mg/l Boron mg/l Doc Ref: Q RP-1399 Revision: 1 Page 78

79 Hutton Sandstone Precipice Sandstone Bandanna Formation Parameter Units Count Min Max Average Count Min Max Average Count Min Max Average Cadmium mg/l Chromium (III+VI) mg/l Cobalt mg/l Copper mg/l Iron mg/l Lead mg/l Lithium mg/l Manganese mg/l Molybdenum mg/l Nickel mg/l Selenium mg/l Silver mg/l Strontium mg/l Zinc mg/l Total Organic Carbon mg/l Methane mg/l Note: concentrations report <LOR, were assumed to be =LOR for calculating statistics Doc Ref: Q RP-1399 Revision: 1 Page 79

80 Hutton Sandstone EC (us/cm) 1,264 ph 9.03 Evergreen Formation Precipice Sandstone EC (us/cm) 234 ph 8.00 Rewan Formation Bandanna Formation EC (us/cm) 11,902 ph 8.43 Figure 10: Schematic Stratigraphy with Associated Physicochemical Parameters 6.5. Third party Groundwater Users Groundwater abstraction for non-petroleum and gas purposes in the Surat CMA includes agricultural use; industrial use; town water supply; and, stock and domestic use. The following third party groundwater users have been identified within the vicinity of the Project area: No third-party groundwater users abstracting water directly from the Bandana Formation were identified through dataset a search of the Queensland government groundwater database and the UWIR (2016), within the vicinity of the Project. The potential future use of Bandanna formation is limited due to the presence of more suitable targets at shallower depths. The Precipice Sandstone is accessed by a number of groundwater users in the vicinity of the Project area. A total of 32 groundwater bores installed for stock and domestic water supply purposes and screened within the Precipice Sandstone have been identified (refer to Figure 11). The 2016 UWIR (OGIA, 2016a) estimates the average groundwater abstraction from the Precipice Sandstone bores is 2.3ML/year/bore, however actual abstraction rates from bores within the vicinity of the Project area is unknown. 251 third-party groundwater bores sourcing groundwater from the Hutton Sandstone are located within the vicinity of the Project area. The average groundwater abstraction for stock and domestic purposes is 1.4 ML/year/bore. These bores have not been mapped in Figure 11 due to the number of bores within the vicinity of the Project area and have not been presented as part of this assessment due to the predicted limited potential impacts associated with the Project. This is further discussed in Section 6.8. A total of 62 bores sourcing groundwater from the Evergreen Formation (including the Boxvale Sandstone Member) are located within the vicinity of the Project area with an average abstraction rate of 2.3/ML/year/bore. These bores have not been mapped in Figure 11 due to the number of bores within the vicinity of the Project area and have not been presented as part of this assessment due to the predicted limited potential impacts associated with the Project. This is further discussed in Section 6.8. Doc Ref: Q RP-1399 Revision: 1 Page 80

81 Figure 11: Precipice Sandstone Groundwater Users (KCB, 2017) 6.6. Groundwater Dependent Ecosystems Springs, including those which are classified as the TEC The community of native species dependent on natural discharge of groundwater from the Great Artesian Basin' (EPBC groundwater community) are known to occur in the vicinity of the Project area. There are seven spring complexes within proximity to the Project (Lucky Last, Abyss, Ponies, Scott Creek, Springrock Creek, 311 and Yebna 2 (591)) and six watercourse springs (W39, W40, W59, W80, W81 and W82) (refer to Figure 12). A summary of each spring is provided in Table 12 (OGIA 2016a). Doc Ref: Q RP-1399 Revision: 1 Page 81

82 Lucky Last Table 12: Springs within Proximity to the Project Area Name Source aquifer Geological control Wetland Type 1 Boxvale Sandstone Member of the Evergreen Formation EPBC Act listed species present Fault 1a Eriocaulon carsonii Abyss Hutton Sandstone Outcrop 2 Eriocaulon carsonii Ponies Precipice Sandstone Outcrop 4b Scott Creek Hutton Sandstone Fault 1a and 1b Eriocaulon carsonii Springrock Creek Precipice Sandstone Outcrop 3 Nil 311 Precipice Sandstone Outcrop 3 Nil Yebna 2 (591) Precipice Sandstone Outcrop 1a Nil W39 on Dawson River Upper Hutton Sandstone Outcrop 3 Nil W40 on Dawson River Precipice Sandstone Outcrop 3 Nil W59 on Eurombah Creek W80 on Hutton Creek W81 on Hutton Creek W82 on Injune Creek Upper Hutton Sandstone Upper Hutton Sandstone Upper Hutton Sandstone Upper Hutton Sandstone Note 1 (sourced from OGIA 2016a): Outcrop 3 Nil Outcrop 3 Nil Outcrop 3 Nil Outcrop 3 Nil Type 1 - Permanent fresh-to-brackish wetlands located outside drainage lines with well-developed peat wetland soils and dense vegetation cover. These wetlands are mainly fed by regional groundwater systems with some local groundwater system contributions. There are two subtypes: - Type 1a is located on the floodplain or within a palustrine landscape setting. - Type 1b is located at the interface between the floodplain and riverine environments and is influenced by surface-water flows. This wetland type is associated with artesian conditions and hydraulic mechanisms Type 2 - Semi-permanent brackish wetlands located outside drainage lines with minor wetland soils and minor vegetation cover. These wetlands are mainly fed by regional groundwater systems and are associated with hydraulic mechanism Type 3 Permanent to semi-permanent riverine wetlands, with minor wetland soil development and moderate vegetation cover. These wetlands are mainly fed by local and regional groundwater systems with significant influence of surface-water flows. These wetlands are associated with hydraulic mechanism. Doc Ref: Q RP-1399 Revision: 1 Page 82

83 Type 4 Semi-permanent fresh riverine to palustrine wetlands, with minor wetland soil development and moderate vegetation cover. These wetlands are mainly fed by local groundwater systems. There are two subtypes: - Type 4a is located within a riverine environment with deep, sandy alluvial deposits (non-gab). - Type 4b is located within a riverine-to-palustrine environment with shallow or no consolidated material. These wetlands can form in areas of significant topography in the northern Surat Basin 700, ,000 CARNAR VON HIGHWAY ARCADIA VALLE Y ROA D DAWSON RIVER RO BINSON CREEK BAFFLE CREEK 7,100,000 7,150,000 FORFAR IN JUNE ROAD INJUNE INJUNE C REE K TAROOM W80 Lucky Last / Abyss Spring Rock Creek INJUNE ROAD C ARNARVON W82 EUROMBAH C REEK HUTTON ROM A CREEK TAROOM ROAD W40 W Yebna 2 Ponies W59 W39 Scotts Creek YULEBA ROAD TAROOM HORSECREEK DEVELOPMENTAL ROAD YULEBA CREEK km PROJECTION 1. Horizontal Datum: GDA94 2. Grid Zone: Vertical Datum: Mean Sea Level 4. Scale: 1:750,000 Vent Spring (Precipice) Watercourse Spring (Precipice) Vent Spring (Other) Watercourse Spring (Other) Town River / Creek Principal Road Minor Road Precipice / Bandanna Sub- Crop (OGIA, 2016) North-West Development Area North-East Development Area Spring Gully Development Area Approved Spring Gully Development Area Petroleum Leases (DNRM) NOTES: 1. Lease locations sourced from DNRM, Roads, Rivers, Towns, Railway: Geodata Topo 250K Series 3 Geoscience Australia May Third-party bores and springs sourced from APLNG, 2016 and OGIA, 2016 Figure 12: Location of Springs within Proximity to the Project (KCB, 2017) Doc Ref: Q RP-1399 Revision: 1 Page 83

84 6.7. Groundwater Modelling Klohn Crippen Berger Ltd (KCB) (2017) undertook a hydrogeological assessment for the Project to assess the potential impact on groundwater resources, ecological communities and threatened species listed under the EPBC Act as a result of CSG water extraction and injection (refer to Appendix 14). Groundwater modelling using MLU for Windows was carried out to identify the potential hydrogeological impacts of the proposed CSG production within the Project area and injection of treated CSG water on the Hutton Sandstone, Boxvale Sandstone Member, Precipice Sandstone and the Bandanna Formation. The following modelling scenarios were considered to assess Project impacts: Scenario A: CSG water extraction which was based on the P50 (median) predicted production rate from the Australia Pacific LNG stochastic reservoir model within the NEDA and NWDA. Scenario B: CSG water extraction and the injection of treated CSG water injection produced by the Project. To be conservative, it is assumed all water produced by the Project will be injected and not utilised in alternative means of water management. Water injection targets into the Precipice Sandstone in accordance with the existing operational scheme. The regional cumulative impact modelling undertaken by OGIA (2016a) provides an estimate of the predicted drawdown associated with CSG from multiple developments, however the model does not include proposed water extraction from the Project. Furthermore, the model does not include CSG production wells from two other approved development areas within the vicinity of the Project, as well as the two, already existing, Australia Pacific LNG aquifer injection operations. The cumulative impact assessment undertaken for this Project considered the Projects CSG water extraction and injection, the regional cumulative impact modelling undertaken by OGIA (2016a) and the following not captured in the 2016 UWIR model: 29 existing wells within the NEDA. 11 wells within the southern portion of PL418 (EPBC referral 2016/7720). Full scale injection (5ML/d operational capacity) at Spring Gully into the Precipice Sandstone. Injection into the Precipice Sandstone at Reedy Creek within the Australia Pacific LNG EIS Project 2009/4974. The following modelling scenarios were undertaken to assess cumulative impacts: Scenario C: CSG water production from existing wells in PL417 and PL418, injection from Spring Gully injection scheme (to a maximum of 5ML/d) and predicted drawdown impacts from the UWIR. Scenario D: Scenario C including the Reedy Creek Aquifer Injection Scheme Potential Hydrological Impacts of the Project Scenario A As described above, Scenario A assessed the potential impacts associated with the extraction of CSG water from the Project. The range of net groundwater level displacement predicted at the Precipice groundwater bores are presented in Figure 13. As discussed in Section 6.5, Hutton Sandstone and Boxvale Sandstone Member third party bores have not been specifically identified as part of this assessment due to the predicted limited drawdown impacts on these aquifers as a result the Project, as identified through the modelling sensitivity analysis (KCB, 2017). This is highlighted in the results provided below. The range of net displacement for the Precipice Sandstone, Hutton Sandstone and Boxvale Sandstone Member sourced springs are presented in Figure 14, Figure 15 and Figure 16, respectively. A summary of the results are as follows: Doc Ref: Q RP-1399 Revision: 1 Page 84

85 The maximum drawdown in the Bandanna Formation is 1,028m. There are however no registered bores or springs sourcing water from the Bandanna Formation. All 32 Precipice Sandstone bores showed less than m of groundwater level drawdown impact as a result Scenario A (Figure 13). The head response in the Precipice Sandstone springs to Scenario A is negligible, with a maximum predicted drawdown near the end of CSG operations of less than m (Figure 14). This predicted maximum drawdown is within the natural diurnal variation of groundwater levels within the Precipice Sandstone. Drawdown in the Hutton Sandstone in Scenario A is predicted to be negligible (<1mm) due to the attenuating effect of the Evergreen Formation aquitard. The head response in the Hutton Sandstone springs due to Scenario A is negligible, with a maximum predicted drawdown near the end of CSG operations of around m (Figure 15). The maximum predicted drawdown in the Hutton Sandstone highlights the limited hydraulic connectivity across the Evergreen Formation, which is further supported by the monitoring results. Head response at the Lucky Last spring (Boxvale Sandstone Member sourced spring), as a result of Scenario A is presented in Figure 16, with three head responses provided. These head responses represent the positioning of the Boxvale Sandstone Member within the Evergreen Formation, as the thickness of the Evergreen Formation above and below the Boxvale Sandstone Member will influence the hydraulic connection and associated drawdown response from the Project. Based on the three simulation results, the largest predicted drawdown impact is 0.002m which is predicted for the lower Evergreen Formation simulation. The results indicate that the Queensland Water Act 2000 trigger threshold for groundwater bores (-5m) and springs (-0.2m) are not predicted to be exceeded for Scenario A. 0 Head Displacemnt (m) Simulation Time (Years) RN58623 RN16752 RN58428 RN8471 RN58283 RN58709 RN16785 RN OE00346 RN14837 RN16851 RN17172 RN24809 RN33433 RN58177 RN58191 RN58472 RN58580 RN58726 RN58878 RN RN RN RN RN RN RN RN RN RN RN RN RN RN RN RN Figure 13: Scenario A Head Change at Precipice Sandstone Groundwater Bore Receptors Doc Ref: Q RP-1399 Revision: 1 Page 85

86 Head Displacement (m) Simulation Time (Years) SPR 311 Prec SPR W40 Prec SPR Yebna2 SPR SPR Spring Rock Ck. Figure 14: Scenario A - Head Change at Precipice Sandstone Sourced Springs 0 Head Displacement (m) Simulation Time (Years) SPR Ponies Hutton SPR Scotts Ck Hutton SPR Lucky Last SPR W14 Hutton SPR W15 Hutton SPR W39 Hutton SPR W59 Hutton SPR W80 Hutton SPR W81 Hutton SPR W82 Hutton SPR Abyss Hutton Figure 15: Scenario A - Head Change at Hutton Sandstone Sourced Springs Doc Ref: Q RP-1399 Revision: 1 Page 86

87 0 Head Displacement (m) NWDA & NEDA CSG, No Inj, upper Evergreen sequence NWDA & NEDA CSG, No Inj, central Evergreen sequence NWDA & NEDA CSG, No Inj, lower Evergreen sequence Simulation Time (Years) Figure 16: Scenario A - Head Change at Boxvale Sanstone Member Sourced Springs Scenario B Scenario B assessed the potential impacts associated with the extraction of CSG water from the Project and injection of treated CSG water produced from the Project into the Precipice. The range of net groundwater level displacement predicted at the Precipice Sandstone groundwater bores are presented in Figure 17. As discussed in Section 6.5, Hutton Sandstone and Boxvale Sandstone Member third party bores have not been specifically identified as part of this assessment due to the predicted limited drawdown impacts on these aquifers as a result the Project. This is discussed in the results provided below. The range of net displacement for the Precipice Sandstone, Hutton Sandstone and Boxvale Sandstone Member sourced springs are presented in Figure 18, Figure 19 and Figure 20, respectively. A summary of the results are as follows: There is little difference in the response to the Bandanna Formation between Scenario A and Scenario B, with a maximum drawdown of 1,028m for Scenario B. There are however, no registered bores or springs sourcing water from the Bandanna Formation. A head rise is predicted in all Precipice Sandstone bores as a result of the injection, with bores observing between 0.35m and 0.60m head rise over the first ten years of the operational period (Figure 17), with injection continuing but at reduced rates to approximately 55 years after injection commencement. Levels recover to within 0.03m of starting condition approximately 100 years after the commencement of injection. A head rise is also simulated in the Precipice Sandstone springs, peaking at just over 0.42m (Figure 18Figure 14) at approximately 10 years of operation. The head rise in the Precipice Sandstone is predicted to translate through the overlying Evergreen Formation and into the Hutton Sandstone, although the head rise is predicted to be small, peaking at approximately 0.013m (Figure 19). The simulation also predicts a residual injection effect, although very small, at less than 0.01m. Therefore, no discernible impacts on the Hutton Sandstone aquifer and associated springs are predicted as a result of Scenario B. Response to injection in the Precipice Sandstone is predicted in all three simulation variations of the Boxvale Sandstone member at Lucky Last Spring (Figure 20), with the greatest influence modelled for the lower Evergreen Formation scenario, producing a maximum operational head rise of approximately 0.3m. The vertical proximity of the Boxvale Sandstone member to the Doc Ref: Q RP-1399 Revision: 1 Page 87

88 Precipice Sandstone is the main driver for the generation of injection related head rise and recovery post-injection. The closer the two units are together, the better the hydrogeological interconnectivity, and the more dominant the Precipice Sandstone response is in the Boxvale Sandstone member. The results indicate that neither the spring trigger (-0.2m) or groundwater bore trigger (-5.0m) thresholds are exceeded as a result of Scenario B Head Displacement (m) Simulation Time (Years) RN58623 RN16752 RN58428 RN8471 RN58283 RN58709 RN16785 RN OE00346 RN14837 RN16851 RN17172 RN24809 RN33433 RN58177 RN58191 RN58472 RN58580 RN58726 RN58878 RN RN RN RN RN RN RN RN RN RN RN RN RN RN RN RN Figure 17: Scenario B - Head Change at Precipice Sandstone Groundwater Bore Receptors Doc Ref: Q RP-1399 Revision: 1 Page 88

89 Head Displacement (m) Simulation Time (Years) SPR 311 Prec SPR W40 Prec SPR Yebna2 SPR SPR Spring Rock Ck. Figure 18: Scenario B - Head Change at Precipice Sandstone Sourced Springs Head Displacement (m) Simulation Time (Years) SPR Ponies Hutton SPR Scotts Ck Hutton SPR Lucky Last SPR W14 Hutton SPR W15 Hutton SPR W39 Hutton SPR W59 Hutton SPR W80 Hutton SPR W81 Hutton SPR W82 Hutton SPR Abyss Hutton Figure 19: Scenario B - Head Change at Hutton Sandstone Sourced Springs Doc Ref: Q RP-1399 Revision: 1 Page 89

90 Head Displacement (m) NWDA & NEDA CSG, Spring Gully Inj, upper Evergreen sequence NWDA & NEDA CSG, Spring Gully Inj, central Evergreen sequence NWDA & NEDA CSG, Spring Gully Inj, lower Evergreen sequence Simulation Time (Years) Figure 20: Scenario B - Head Change at Boxvale Member Sourced Springs Significant Impact Assessment The minor changes in hydrology ( m for Scenario A to 0.65m for Scenario B) as a result of the Project is of insufficient scale or intensity to reduce the current or future use of the resource for third party users (both groundwater waters and springs) and does not create a material risk of such a reduction in use occurring. As a result, no significant impact is likely to occur. The use of injection as a mitigation measure for CSG water extraction is not required due to the maximum drawdown of only m which is within the measured natural daily variation within existing monitoring records as a result of barometric pressure changes. The existing and proposed continued use of injection of treated CSG water is utilised for the management of CSG water A summary of the assessment of potential impacts against the DoEE (2013b) significant impact criteria (Section 5.3, Changes to Hydrological Characteristics) is provided in Table 13. The potential impacts to springs has also been assessed against Significant Impact Guidelines 1.1 (DoEE 2013a). Based on the results of the Project-specific modelling, and supported by the Precipice and Hutton Sandstone groundwater monitoring records which show there has not been a drawdown of groundwater levels in these hydrostratigraphic units to date as a result of depressurisation of the Bandanna Formation (since 2005) (Section 6.3), a net drawdown of groundwater pressure, or reduction in discharge at the spring complexes as a result of the Project is not predicted. Given the minor changes to hydrology at the springs, it will not result in the following: Reduce the extent of an ecological community. Fragment or increase fragmentation of an ecological community. Adversely affect habitat critical to the survival of an ecological community. Modify or destroy abiotic (non-living) factors (such as water, nutrients, or soil) necessary for an ecological community s survival, including reduction of groundwater levels, or substantial alteration of surface water drainage patterns. Cause a substantial change in the species composition of an occurrence of an ecological community, including causing a decline or loss of functionally important species. Cause a substantial reduction in the quality or integrity of an occurrence of an ecological community, including, but not limited to: Doc Ref: Q RP-1399 Revision: 1 Page 90

91 - Assisting invasive species, that are harmful to the listed ecological community, to become established, or - Causing regular mobilisation of fertilisers, herbicides or other chemicals or pollutants into the ecological community which kill or inhibit the growth of species in the ecological community, or Interfere with the recovery of an ecological community. Stygofauna are aquatic invertebrates which are found in aquifers, and have been identified across Australia. Key factors in determining suitability of an aquifer for stygofauna include; pore space; depth below ground level; and water quality (Hose et al 2015). The abundance and diversity of stygofauna decreases with depth and are rarely found below 100m. The Precipice Sandstone in the vicinity of the Project ranges from approximately 200m to 700m below ground level, does not outcrop in the Project area, and is therefore unlikely to support stygofauna. In addition, while the water salinity is generally very fresh (<250µS/cm), and the water is reducing (average redox potential -62mV) and methane rich (up to 12.6mg/L), the nearest outcrop area from where recharge could flow to the Project area is over 20km away (to the north-west). Based on the factors identified in Hose et al (2015), the likelihood of stygofauna presence in the Precipice Sandstone within the Project area is considered low. Accordingly, surveys for stygofauna are not considered necessary. Potential impacts to the Hutton Sandstone for both Scenario A and B are limited to <1mm drawdown in Scenario A and 0.013m headrise in Scenario B. These head changes are within the natural daily variation as a result of barometric pressure changes (commonly around 0.05m/day, but up to 0.1m/day). If stygofauna are assumed to be present within the Hutton Sandstone, the risk to stygofauna as a result of the Project is considered insignificant. Table 13: Significant Impact Criteria (Section 5.3 Changes to Hydrological Characteristics) Groundwater Significant Impact Criteria Section 5.3 Flow Regime Recharge rates to groundwater Aquifer pressure or pressure relationship between aquifers and groundwater table and potentiometric surface levels Comment The Project does not include abstraction from surface watercourses and groundwater extracted as part of the Project will be treated/contained within the existing SGRA infrastructure. Watercourse springs in the vicinity of the Project area predominantly source water from the Hutton Sandstone aquifer, with the exception of the W40 watercourse spring (Precipice Sandstone source) within the Dawson River. Based on the results of the Project-specific modelling, no drawdown is predicted at these spring locations (refer to Sections and 6.8.2), therefore any baseflow provided to the Dawson River by W40 is unlikely to be impacted. No other baseflow mechanisms from the Precipice Sandstone have been identified within proximity to the Project. Therefore, the Project is unlikely to result in any changes to surface water flow regime. Recharge to the Surat Basin aquifers occur where the formation outcrops (OGIA, 2016a). The Precipice Sandstone outcrops to the north and northwest, approximately 20km from the Project area. Recharge to the Precipice Sandstone at the outcrop occurs as a result of direct rainfall infiltration. This assessment has indicated that there will be no drawdown impacts at the outcrop area as a result of the Project, and therefore no impacts to the recharge rates to groundwater are predicted. Monitoring data shows that there are generally significant differences in pressure heads between nested monitoring bores. The results of the modelling indicate that there will be negligible change to water levels in the Precipice and Hutton Sandstones and will therefore not change the relationships between the pressures in the aquifers Doc Ref: Q RP-1399 Revision: 1 Page 91

92 Significant Impact Criteria Section 5.3 Comment CSG water extraction is limited to the coal seams within the Bandanna Formation and by necessity for CSG production, the potentiometric surface will be reduced within that formation. Evidence from monitoring bores in the vicinity of the existing CSG fields at Spring Gully and Fairview indicate that despite the significant existing/historical depressurisation of the Bandanna Formation of up to 300m, there is no discernible impact to the Precipice Sandstone (UWIR, 2016a). Groundwater/surface water interactions and river/floodplain connectivity Inter-aquifer connectivity Coastal processes Watercourse springs in the vicinity of the Project area predominantly source water from the Hutton Sandstone aquifer, with the exception of the W40 watercourse spring (Precipice Sandstone source) within the Dawson River. Based on the results of the Project-specific modelling, no drawdown is predicted at these spring locations, therefore any baseflow provided to the Dawson River by W40 is unlikely to be impacted. No other baseflow mechanisms from the Precipice Sandstone have been identified within proximity to the Project. Other registered spring complexes (Yebna 2, 311, Springrock Creek) within the assessment area are listed as having the Precipice Sandstone as their source aquifer. A Project-specific groundwater model of the Project was undertaken to assess potential localised aquifer impacts while also incorporating the influence of injecting the Project water at Spring Gully. The results indicate that the spring trigger (>0.2m drawdown) will not be exceeded. The Project-specific modelling also identified limited influence of the Project extraction and aquifer injection on the groundwater levels in the Boxvale Sandstone Member and the Hutton Sandstone. Therefore, no impacts to the springs sourcing groundwater from the Boxvale Sandstone Member and Hutton Sandstone are expected. Potential impacts to groundwater and surface water interactions as a result of the Project are unlikely and will not result in any changes to river/floodplain connectivity. A project-specific groundwater model of the Project was developed to assess potential inter-aquifer connectivity. Through testing of multiple conceptualisations, the modelling identified limited potential for hydraulic connection between the Bandanna Formation and the overlying Precipice Sandstone and more so, the limited hydraulic connection between the Precipice Sandstone and the Hutton Sandstone, through the Evergreen Formation. These model predictions are further supported by groundwater level monitoring records from adjacent monitoring bores installed within the Precipice and Hutton Sandstone. Limited hydraulic connection between the Bandanna Formation and the Boxvale Sandstone Member has also been predicted. The Project area is located in south central Queensland. Given the distance to the coast and no significant impacts to surface water from the proposed development, changes to coastal processes will not occur Potential Groundwater Quality Impacts Construction, Operation and Decommissioning of CSG Wells A chemical risk assessment has been undertaken by ERM (Appendix 17) to assess the potential impacts to water resources as a result of the fluids used during the construction, operation and decommissioning of CSG wells (as described in Section 2.5.2). The assessment included: An inventory of the chemical additives to be used, including typical mass and concentration, general purpose and function. Additionally, a compilation of the chemical properties of each of the additives to assess the chemical hazard properties. Doc Ref: Q RP-1399 Revision: 1 Page 92

93 An assessment of potential exposure pathways within the Project area for identified water resources, environmental and human receptors at both the surface and subsurface. Potential exposure pathways that are not considered to represent a viable connection to receptors were also identified. A qualitative assessment of potential hazards to identified receptors with consideration of the chemical dose and the chemical life-cycle under specific site conditions at both the surface and subsurface. Characterisation of the risk and evaluation of the management framework in place. The risk assessment included a qualitative risk assessment as part of a tiered approach to identify potential pathways that warranted further quantitative assessment. The quantitative assessment was completed using groundwater modelling to assess the impact of a potential loss of drilling mud into an aquifer. A Conceptual Site Model was developed which is the description of all plausible mechanisms by which receptors may be exposed to contamination. For an exposure to be considered possible, a mechanism ( pathway ) must exist by which contamination from a given source can reach a given receptor. The following were evaluated to determine if there was a complete source-pathway-receptor (SPR) linkage: A source of chemical contamination (additives used in drilling mud, cement and completion/workover fluids). A mechanism for release of contaminants from identified sources (e.g. spill, volatilisation into air or dissolution into groundwater). A contaminant retention or transport medium (e.g. soil, air, groundwater etc.). Potential receptors of contamination (e.g. aquatic species, surface water, people). A mechanism for chemical intake by the receptors at the point of exposure (ingestion, dermal contact, inhalation or a combination thereof). Whenever one or more of these elements are missing, the SPR linkage is incomplete and the potential risk to the identified receptor is considered unlikely. Based on the sources, migration pathways and receptors, the following SPR linkages were identified and further assessed: On-site workers may have direct contact with drilling mud, cement and completion/workover fluid chemicals by: - Handling of chemicals (drilling additives, cement additives, completion/workover and abandonment additives) at surface prior to use (health of workers). - Handling of drilling mud, cement, completion/workover and abandonment additives at the surface from return product (health of workers). - Accidental release (spills and leaks) of chemicals used in drilling mud, cement, completion/workover and abandonment additives to soils at the well site. Off-site receptors (people and ecological receptors) may have potential for limited exposures with chemicals through: - Accidental release (spills and leaks) or loss of containment of chemicals used in drilling mud, cement and completion/workover fluids to soils or surface waters; Migration of drilling muds from losses into the aquifers (lost circulation). The toxicity of the additives were assessed and all were considered to not pose a risk to human health if handled in accordance with the Origin s management plans and guidance included in the SDS. All of the Doc Ref: Q RP-1399 Revision: 1 Page 93

94 additives are potentially environmentally harmful in their undiluted forms if spilled directly onto soils or surface water bodies. On dilution, including the mixing of drilling/completion fluids, the hazardous properties of the additives are reduced. With the implementation of the appropriate controls, the risk to human health and the environment is considered low. The migration of drilling muds into aquifers was further assessed using an analytical transport and fate groundwater model. The method simulates how a conservative tracer (in this case chloride) would move in a Darcy flow column in the direction of flow after being injected into the aquifer. The groundwater modelling undertaken provides a worst case prediction of how far a contaminant could move in the groundwater system over time for the following reasons: Chloride is a conservative tracer (i.e. no retardation or decay). The input concentration of 34,000mg/L of potassium chloride was based on the maximum concentration that would be present in a vertical drilling mud mixture. The finite input volume of 55m³ (350bbl) of drilling mud assumes a full mud system loss. A number of existing Precipice Sandstone and Hutton Sandstone groundwater users have been identified within the vicinity of the Project area. Water from the Precipice Sandstone is typically used for potable water and stock use while water from the Hutton is only used for stock due to elevated salinity. There are currently no identified third party groundwater users abstracting water directly from the Bandanna Formation within the vicinity of the Project area. As described in Section 6.6, a number of EPBC groundwater communities access water from the Hutton Sandstone and Precipice Sandstone. Three hydrogeological formations were modelled, the Hutton Sandstone, Precipice Sandstone and the Bandanna Formation. To assess the risk to current and/or potential groundwater users the modelling results were compared with the Australian Drinking Water Guideline aesthetic value for chloride of 250mg/L (NHMRC, 2016). This guideline value is relevant for the Precipice Sandstone aquifer only. For the Hutton Sandstone and Bandanna Formation, the relevant guideline is the ANZECC stock drinking water guidelines, for which there is no guideline value for chloride (ANZECC, 2000). To assess potential risk of groundwater dependent ecosystems a screening of 96 mg/l for chloride was used, based on the effect on salinity changes to freshwater ecosystems from the ANZECC (2000; trigger levels range from 150 to 250µS/cm salinity equivalent to 96 to 160mg/L). The analytical modelling showed that the maximum expected concentration of chloride within the Precipice Sandstone at 50m from the source will be 91mg/L, which is below the Australian Drinking Water Guideline value for chloride of 250mg/L (NHMRC, 2016) and the freshwater ecosystems screening value of 96mg/L. In the Hutton Sandstone and Bandanna Formation, the analytical modelling showed that the maximum expected concentration of chloride at 50m and 100m from the source will be 2,867mg/L and 1,014mg/L respectively. At 500m from the source, the maximum expected concentration of chloride will be 91mg/L, which is below the freshwater ecosystems screening value of 96mg/L. The above concentrations assume the lower estimate of hydraulic conductivity in a low dispersive system. Running the model with a higher hydraulic conductivity, low porosity and a high hydraulic gradient, the groundwater velocities are high and hence the plume will move fast, but will also disperse. Under this scenario, the maximum observed concentration in the Hutton Sandstone and Bandanna Formation will be 91mg/L at 50m from the source. The modelling results for chloride are readily scalable for other additives, based on their concentration relative to the concentration of chloride. Key additives evaluated against the chloride modelling were tetrakis (hydroxymethyl) phosphonium sulfate (Wildcat 555; based on its water solubility and moderate toxicity to human health) and polyether amine (KLA-STOP; based on it s low to moderate human health toxicity and its low potential biodegradability and corresponding potential for persistence in the environment). Doc Ref: Q RP-1399 Revision: 1 Page 94

95 Tetrakis (hydroxymethyl) phosphonium sulfate would be expected to be low risk, based on its ability to readily degrade. This is particularly relevant for the low hydraulic conductivity scenarios in which the migration to maximum concentrations may take hundreds to thousands of years. Over this time scale, the use of chloride as a surrogate for tetrakis(hydroxymethyl)phosphonium sulfate is overly conservative. Given the ability of tetrakis(hydroxymethyl)phosphonium sulfate to readily degrade, it would not be expected to reach a potential groundwater users or spring Polyether amine would have the same risk potential as chloride, as it is not expected to degrade over time. It does however have the potential to attenuate more than chloride over time. Overall, the risk assessment concluded the additives present a Low risk for all SPR linkages as summarised in Table 14. Table 14: Summary of Risks Source Pathway Receptor Risk 1 Control Pre-mixed additives and additives within the drilling mud mixture Pre-mixed additives and additives within the drilling mud mixture Direct contact at surface Spillage to ground or surface water at surface Workers at wellhead Ecological Low Low Drilling and Completion Governance Framework (Q RP-010), for example; Materials handling training for staff and contractors should include both health and safety and environmental protection training, with particular emphasis on avoiding and reporting spills. Selection of handling equipment reducing manual handling/mixing. Handling chemicals following guidance included in the SDS to reduce direct contact and inhalation exposures. Additives within the drilling mud mixture in the subsurface Migration of remnant additives within the drilling mud mixture via subsurface Overlying aquifers which may in turn provide base flow to surface waters. Human health (groundwater users, surface water users), ecological (livestock and irrigation, and surface water ecology Low (Groundwater modelling resulted in limited migration and low potential for risk) Lost circulation material added to the drilling mud as a proactive measure prior to encountering losses. Loss zones are typically cased off to isolate further losses as soon as possible. Switch to fresh water with no drilling mud additives Migration of remnant additives within the drilling mud mixture via well casing failure Overlying aquifers which may in turn provide base flow to surface waters. Human health (groundwater users, surface water users), Ecological (livestock and irrigation, and Low (Groundwater modelling resulted in limited migration and low potential for risk) Doc Ref: Q RP-1399 Revision: 1 Page 95

96 Source Pathway Receptor Risk 1 Control surface water ecology) 1 - A determination of Low indicates the level of potential exposures are significantly lower (over an order magnitude lower) than levels that would be considered to pose a risk (DoE, 2016). The conclusions are based on the conclusion that potentially SPR linkages either do not exist or are highly unlikely to be complete as well as the over low toxicity of the additives and drilling mud and cement mixtures Production Changes in water quality during the production phase are not anticipated. As the Precipice Sandstone aquifer overlies the Bandanna Formation, any water extracted from the CSG production wells is drawn down within the Bandanna Formation and therefore, due to the head differential between the formations any interaction or flow of water would be from the Precipice Sandstone to the Bandanna Formation. Therefore, a change in the water quality of the Precipice Sandstone water is not likely to occur at the Precipice Sandstone groundwater receptors for the duration of the Project. The Precipice Sandstone comprises a better water quality than the Bandanna Formation, therefore, the transfer of groundwater from the Precipice Sandstone to the Bandanna Formation will not result in an impact to the Bandanna Formation. No measurable drawdown in the Hutton Sandstone groundwater level was predicted as a result of Scenario A. However, with the inclusion of the Spring Gully injection scheme Scenario B, a minor head rise (0.013m) in the Hutton Sandstone groundwater level is predicted. Water quality impacts associated with the transfer of Precipice Sandstone water into the Hutton Sandstone is not predicted as the water quality of the Precipice Sandstone is better than the Hutton Sandstone (Section 6.4) Injection A risk assessment has been undertaken as part of the Spring Gully Aquifer Injection Management Plan (Appendix 11) to determine the potential risks of injection into the Precipice Sandstone. The following have been identified as potential risks: Pathogens introduced through the injectate stream, degrading the environmental values of in-situ groundwater. Inorganic chemicals introduced through the injectate stream, or dissolution of metals from aquifer minerals, degrading the environmental value of in-situ groundwater. Increased salinity or sodicity introduced through the injectate stream degrading the environmental value of in-situ groundwater. Nutrients (organic carbon, nitrogen, phosphorus) introduced through the injectate stream degrading the environmental value of in-situ groundwater. Organic chemicals, including disinfection by- products, degrading the environmental value of insitu groundwater. Turbidity and particulates introduced through the injectate stream degrading the environmental value of in-situ groundwater and/or well performance. Radionuclides introduced through the injectate stream, or released from aquifer matrix, degrading the environmental value of in-situ groundwater. Over-pressurisation of injection well, causing rupture of aquitard. Contaminant migration in fractured rock and karstic aquifers. Aquifer dissolution and aquitard and well stability. Doc Ref: Q RP-1399 Revision: 1 Page 96

97 Impacts on groundwater dependant ecosystems. Bore failure causes injectate to enter non- target aquifer. In-situ groundwater of non- target aquifer has differing water quality to that of injectate. Clogging (including deposition of suspended solids from CSG water, air entrainment and gas binding, biological growth, and geochemical reactions). With the following appropriate controls in place, the residual risk to the Precipice Sandstone and the third party groundwater users and EPBC community springs is low (Appendix 11): Appropriate design and construction of bores. Treatment of CSG water through the WTF and PRP. Online monitoring of EA limits, with off specification water directed back to WTF feed pond. Adaptive management 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 aquifer injection, the adequacy of monitoring can be reviewed to assist management of that risk. Hydrogeochemical modelling was undertaken to assess the technical feasibility of injection into the Precipice Sandstone at the Spring Gully site (Origin, 2015) and, the assessment of potential water quality impacts associated with possible changes in the water treatment process on the injection bore infrastructure and the Precipice Sandstone water quality (KCB, 2017b). Although both of these assessments were undertaken for specific objectives (i.e. injection technical feasibility and impacts on injection bore infrastructure and the aquifer), the results from each model can be used to support the assessment of potential impacts to groundwater users as part of this groundwater assessment. Key results from the hydrogeochemical modelling of the Spring Gully injection scheme include: Changes in the water treatment process (e.g. removal of the deoxygenation plant) is not predicted to result in the worsening of the injectate/precipice Sandstone aquifer water quality for contaminants of potential concern. A change in the water treatment process (e.g. removal of deoxygenation plant, coating of steel bore casing with Fe-oxides/Fe-oxy-hydroxides) is required to mitigate potential clogging or corrosion of the injection bore infrastructure. Evidence of injected water rising to the surface has not been observed and the potential of injectate water to rise to the surface through the injection bore annulus has been mitigated through appropriate bore construction, which comprises a pressure cemented annulus from above the injection bore screens (approximately 420m below ground surface) to the surface. Monitoring of the Hutton Sandstone at the injection site to date shows no measurable influence of injection on the water level, and therefore no impact on the Hutton Sandstone water quality is predicted. In the event a connection to the surface does occur, the assessment identified that the changing ph/redox conditions promote the attenuation of the water quality parameters. This is highlighted by the model output concentrations for this scenario (key modelled parameters include iron, sulphate, zinc, arsenic), where concentrations are predicted to be below ANZECC (2000) 95% Species Protection Fresh Water guidelines for parameters of concern within 250m of the injection bore. The closest springs are more than 10km from the injection site. Results from the hydrogeochemical modelling indicate that the geochemical changes associated with injection are limited to within ~500m of the injection point within the Precipice Sandstone (KCB, 2017). Resultant concentrations from the injection are predicted to be within Doc Ref: Q RP-1399 Revision: 1 Page 97

98 ANZECC/ARMCANZ (2000) and Australian Drinking Water guidelines for key modelled parameters identified above. In addition to this, the Project-specific groundwater modelling completed as part of this assessment identifies negligible hydraulic connection between the Precipice Sandstone and the Hutton Sandstone, through the Evergreen Formation. Therefore, groundwater receptors associated with the Hutton Sandstone are not anticipated to be impacted by the Spring Gully injection scheme. As a result, additional mass transport numerical modelling is not considered to be required. The limited radius of extent of the geochemical impacts from the injection bore, and the limited connectivity between the Precipice Sandstone and the Hutton Sandstone across the Evergreen Formation highlights that the potential risk to landholder bores sourcing water from the Precipice Sandstone and Hutton Sandstone due to the Spring Gully injection is low Significant Impact Assessment A summary of the assessment of potential impacts against the DoEE (2013a) significant impact criteria (Section 5.4, Changes to Water Quality) is provided in Table 15 (refer to Appendix 14 for further details). Water quality changes as a result of the Project is of insufficient scale or intensity to reduce the current or future use of the resource for third party users (both groundwater waters and EPBC groundwater communities) and does not create a material risk of such a reduction in use occurring. As a result, no significant impact is likely to occur. Table 15: Significant Impact Criteria (Section 5.4 Changes to Water Quality) Groundwater Significant Impact Criteria Section 5.4 Create risks to human or animal health or to the condition of the natural environment as a result of the change in water quality Comment Impacts associated with changes to water quality as a result of the Project are not anticipated. As the Precipice Sandstone overlies the Bandanna Formation, any water extracted from the CSG production wells is drawn down within the Bandanna Formation and therefore, due to the head differential between the formations any interaction or flow of water would be from the Precipice Sandstone to the Bandanna Formation. The Precipice Sandstone comprises a better water quality than the Bandanna Formation, therefore, the transfer of groundwater from the Precipice Sandstone to the Bandanna Formation will not result in an impact to the Bandanna Formation. Additionally, limited hydraulic connection between the Precipice Sandstone and the Hutton Sandstone, across the Evergreen Formation, is predicted and supported by groundwater monitoring records. Therefore, impacts to the Hutton Sandstone groundwater quality from the Precipice Sandstone is not anticipated. The quality of the water being injected at Spring Gully will be similar to the water quality of the receiving Precipice Sandstone aquifer. Water quality monitoring has been established to ensure compliance with the EA conditions for both the surrounding aquifer and within the treatment system. Aquifer injection automatically ceases before the water quality limits specified in the EA are reached. EA conditions are based on background water qualities and investigations undertaken prior to the commencement of injection, including comprehensive water quality sampling during injection trials. Hydrogeochemical modelling of the aquifer injection scheme at Spring Gully predicts that no impacts to the water quality of the Precipice Sandstone aquifer is anticipated, with potential changes to the aquifer water quality limited to within a ~500m radius of the Spring Gully injection bore with resultant concentrations from the injection predicted to be within ANZECC/ARMCANZ (2000) and Australian Drinking Water guidelines. The chemical risk assessment of the additives used in the drilling process concluded the potential risk to human health and the environment was low. The potential migration of diluted drilling mud additives to an aquifer is not likely to Doc Ref: Q RP-1399 Revision: 1 Page 98

99 Significant Impact Criteria Section 5.4 Substantially reduces the amount of water available for human consumptive uses or for other uses, including environmental uses which are dependent on water of the appropriate quality Causes persistent organic chemicals, heavy metals, salt or other potentially harmful substances to accumulate in the environment Seriously affects the habitat or lifecycle of a native species dependent on a water resource Comment result in an unacceptable risk to groundwater users or ecological receptors. Quantitative groundwater modelling was conducted based on the highest concentration soluble additive (potassium chloride). The results indicate that in the event of a release of drilling muds into underlying aquifers, it is unlikely to result in risk to human health and the environment as a result of the low toxicity of the chemicals. Regardless, mitigation measures during well construction to reduce loss of circulation minimise this potential pathway. The Project is unlikely to result in a risk to human or animal health, or to the condition of the environment. As described above, impacts associated with changes to water quality are not anticipated as a result of the extraction and injection of CSG water. Project-specific groundwater model was developed to assess potential localised aquifer impacts. Results from this modelling indicate that impacts to groundwater levels are limited to the producing coal seam (Bandanna Formation), with no discernible Project impacts predicted for the overlying aquifers (Precipice Sandstone, Boxvale Sandstone Member, Hutton Sandstone). As a result, no changes to the amount of available water available for human consumptive uses or other uses are anticipated. The chemical risk assessment of the additives used in the drilling process concluded the potential risk to human health and the environment was low. As a result, no changes to the amount of available water available for human consumptive uses or other uses are anticipated. No hydraulic stimulation will be undertaken as part of the Project. The quality of the water being injected at Spring Gully will be similar to the water quality of the receiving Precipice Sandstone aquifer. Water quality monitoring has been established to ensure compliance with the EA conditions for both the surrounding aquifer and within the treatment system. Aquifer injection automatically ceases before the water quality limits specified in the EA are reached. EA conditions are based on background water qualities and investigations undertaken prior to the commencement of injection, including comprehensive water quality sampling during injection trials. Hydrogeochemical modelling of the aquifer injection scheme at Spring Gully predicts that no impacts to the water quality of the Precipice Sandstone aquifer is anticipated, with potential changes to the aquifer water quality limited to within a ~500m radius of the Spring Gully injection bore with the resultant concentrations from the injection predicted to be within ANZECC/ARMCANZ (2000) and Australian Drinking Water guidelines. Therefore, no changes to habitat or lifecycle of a native species dependent on a water resource are expected. The chemical risk assessment of the additives used in the drilling, cementing, completion/workover and abandonment process concluded the potential risk to human health and the environment was low. Of the chemical additives assessed, none met the criteria for bioaccumulation. No oil based mud and benzene, toluene, ethyl benzene, and xylene containing chemicals are used. The quality of the water being injected at Spring Gully will be similar to the water quality of the receiving Precipice Sandstone aquifer. Water quality monitoring has been established to ensure compliance with the EA conditions for both the surrounding aquifer and within the treatment system. Aquifer injection automatically ceases before the water quality limits specified in the EA are reached. EA conditions are based on background water qualities and investigations undertaken prior to the commencement of injection, including comprehensive water quality sampling during injection trials. Hydrogeochemical modelling of the aquifer injection scheme at Spring Gully predicts that no impacts to the water quality of the Precipice Sandstone aquifer is anticipated, with potential changes to the aquifer water quality limited to Doc Ref: Q RP-1399 Revision: 1 Page 99

100 Significant Impact Criteria Section 5.4 Causes the establishment of an invasive species (or the spread of an existing invasive species) that is harmful to the ecosystem function of the water resource There is a significant worsening of local water quality (where current local water quality is superior to local or regional water quality objectives) High quality water is released into an ecosystem which is adapted to a lower quality of water Comment within a ~500m radius of the Spring Gully injection bore with the resultant concentrations from the injection predicted to be within ANZECC/ARMCANZ (2000) and Australian Drinking Water guidelines. Therefore, no changes to habitat or lifecycle of a native species dependent on a water resource are expected. Therefore, no changes to habitat or lifecycle of a native species dependent on a water resource are expected. There are no known invasive species which could be introduced to groundwater as a result of CSG well construction and production. No changes to water quality have been identified as a result of the Project. Therefore, no changes to the water resource which may cause the establishment of an invasive species (or the spread of an existing invasive species) are expected. Impacts associated with the changes in water quality as a result of the Project are not anticipated. As the Precipice Sandstone overlies the Bandanna Formation, any water extracted from the CSG production wells is drawn down within the Bandanna Formation and therefore, due to the head differential between the formations any interaction or flow of water would be from the Precipice Sandstone to the Bandanna Formation. The quality of the water being injected at Spring Gully will be similar to the water quality of the receiving Precipice Sandstone aquifer. Water quality monitoring has been established to ensure compliance with the EA conditions for both the surrounding aquifer and within the treatment system. Aquifer injection automatically ceases before the water quality limits specified in the EA are reached. No impacts to water quality within the Precipice Sandstone are anticipated as a result of the Project. EA conditions are based on background water qualities and investigations undertaken prior to the commencement of injection, including comprehensive water quality sampling during injection trials. Hydrogeochemical modelling of the aquifer injection scheme at Spring Gully predicts that no impacts to the water quality of the Precipice Sandstone aquifer is anticipated, with potential changes to the aquifer water quality limited to within a ~500m radius of the Spring Gully injection bore with the resultant concentrations from the injection predicted to be within ANZECC/ARMCANZ (2000) and Australian Drinking Water guidelines. The chemical risk assessment of the additives used in the drilling process concluded the potential risk to human health and the environment was low. The potential migration of diluted drilling mud additives to an aquifer is not likely to result in an unacceptable risk to groundwater users or ecological receptors. Quantitative groundwater modelling was conducted based on the highest concentration soluble additive (potassium chloride). The results indicate that in the event of a release of drilling muds into underlying aquifers, it is unlikely to result in risk to human health and the environment as a result of the low toxicity of the chemicals. Regardless, mitigation measures during well construction to reduce loss of circulation minimise this potential pathway. The quality of the water being injected at Spring Gully will be similar to the water quality of the receiving Precipice Sandstone aquifer. Water quality monitoring has been established to ensure compliance with the EA conditions for both the surrounding aquifer and within the treatment system. Aquifer injection automatically ceases before the water quality limits specified in the EA are reached. EA conditions are based on background water qualities and investigations undertaken prior to the commencement of injection, including comprehensive water quality sampling during injection trials. Therefore, no changes to ecosystem water qualities are anticipated. Doc Ref: Q RP-1399 Revision: 1 Page 100

101 6.10. Cumulative Impacts As described in Section 6.7, an assessment of cumulative impacts was undertaken taking into account the Projects CSG water extraction and injection, the regional cumulative impact modelling undertaken by OGIA (2016a) and the following which are not captured in the 2016 UWIR model: 29 existing wells within the NEDA. Development within Spring Gully South-West Development Area (SWDA) (EPBC 2016/7720). Full scale injection (5ML/d operational capacity) at Spring Gully into the Precipice Sandstone. Injection into the Precipice Sandstone at Reedy Creek within the Australia Pacific LNG EIS Project (EPBC 2009/4974). Two scenarios were considered for the cumulative impact assessment: Scenario C: CSG water production from existing wells in PL417 and PL418, injection from Spring Gully injection scheme (to a maximum of 5ML/d) and predicted drawdown impacts from the UWIR; and, Scenario D: Scenario C including the Reedy Creek Aquifer Injection Scheme. The maximum drawdown from the 2016 UWIR model (OGIA, 2016a) at each of the receptor sites has been assessed against the maximum groundwater level displacement from the MLU modelling, including the proposed Project development and both aquifer injection schemes and CSG water production not included in the UWIR model. Modelling results for the potential cumulative impacts to Precipice Sandstone registered bores are provided in Table 16. Results for the Project impacts are provided with the cumulative drawdown impacts for comparative purposes. Table 16 also presents the proportional contribution of head displacement from Scenario B to the predicted cumulative head displacement. Cumulative drawdown impact results for the Hutton Sandstone third-party bores have not been provided as the potential for Project impacts to groundwater from this unit are interpreted to be negligible due to the attenuating effects of the Evergreen Formation aquitard. Cumulative impacts to the Hutton Sandstone are considered more likely to be influenced by CSG proponents producing from the Walloon Coal Measures overlying the Hutton Sandstone. The cumulative scenario modelling results indicate that two bores are predicted to exceed the groundwater trigger of -5m in Scenario D. However, this exceedance is a result of the existing CSG production as simulated in the UWIR model predictions as no drawdown was predicted in Scenario A and for Scenario B, a headrise up to 0.42m was predicted. Modelling results for the potential cumulative impacts to Precipice Sandstone, Hutton Sandstone and Boxvale Sandstone Member sourced springs are provided in Table 17. Results for the Project impacts are provided with the cumulative drawdown impacts for comparative purposes. Table 17 also presents the proportional contribution of head displacement from Scenario B to the predicted cumulative head displacement. The results indicate that two springs exceed the -0.2m spring trigger in Scenario D. However, this exceedance is a result of the existing CSG production as simulated in the UWIR model predictions as no drawdown was predicted in Scenario A and for Scenario B, a headrise up to 0.36m was predicted. The modelling assumptions should be considered to establish the potential physical change to springsource aquifer head relationships. It is noted that a single hydraulic parameter has been used that best fits all Precipice Sandstone water level responses to the injection response (refer Section of Appendix 14). The optimised model is predicting over 2m of headrise in monitoring bore Spring Gully MB11-P (located in the vicinity of the Yebna 2 and 311 Precipice Sandstone sourced springs), as compared with less than 1m of actual headrise after 2 years of Injection. APLNG (2016) identifies that Doc Ref: Q RP-1399 Revision: 1 Page 101

102 this part of the Precipice Sandstone exhibits higher transmissivities than other areas of the formation. It is considered likely that the model is overpredicting the head rise at Yebna 2, 311 springs and W40 watercourse spring due to simplification of the variability of transmissivities in the modelling. Doc Ref: Q RP-1399 Revision: 1 Page 102

103 Table 16: Predicted Cumulative Impact Assessment Groundwater Bores Scenario A Scenario B Scenario C Scenario D Simulation Details Project Only (NWDA + NEDA) Project + Spring Gully Injection (Project only) Project + Spring Gully Injection (Project + SGRA capped to 5ML/d) + existing NEDA + SWDA Project + Spring Gully Injection (Project + SGRA capped to 5 ML/d) + Reedy Creek Injection + existing NEDA + SWDA Project Yes Yes Yes Yes Spring Gully Injection Yes Yes Yes Existing NEDA, SWDA plus injection of SGRA water to max. 5ML/d Yes Yes Reedy Creek Injection Yes Receptor UWIR (2016) Max DDN (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Percentage Contribution to Cumulative Drawdown / Headrise OE % RN % RN % RN N/A RN N/A RN % RN N/A RN N/A RN % RN % Doc Ref: Q RP-1399 Revision: 1 Page 103

104 Scenario A Scenario B Scenario C Scenario D Simulation Details Project Only (NWDA + NEDA) Project + Spring Gully Injection (Project only) Project + Spring Gully Injection (Project + SGRA capped to 5ML/d) + existing NEDA + SWDA Project + Spring Gully Injection (Project + SGRA capped to 5 ML/d) + Reedy Creek Injection + existing NEDA + SWDA RN % RN % RN % RN % RN % RN % RN % RN N/A RN % RN % RN % RN % RN % RN % RN % RN % RN % RN % RN % Doc Ref: Q RP-1399 Revision: 1 Page 104

105 Scenario A Scenario B Scenario C Scenario D Simulation Details Project Only (NWDA + NEDA) Project + Spring Gully Injection (Project only) Project + Spring Gully Injection (Project + SGRA capped to 5ML/d) + existing NEDA + SWDA Project + Spring Gully Injection (Project + SGRA capped to 5 ML/d) + Reedy Creek Injection + existing NEDA + SWDA RN N/A RN % RN % Note: Cumulative impacts simulation may overestimate the predicted head rise at the groundwater receptors due to: (1) the incorporation of the UWIR maximum drawdown as part of the cumulative head change calculation, which is not linked to a timing for when the maximum drawdown is predicted to occur, therefore, the drawdown may not correlate with the timing of the maximum head changes from the Project specific modelling; and, (2) the transmissivity applied to the Precipice Sandstone is applied as a constant value across the entire model extent, however, higher transmissivity values are observed to the north of the Project area, which would result in a lower predicted head rise at the groundwater receptors. Predictions are rounded to the nearest 0.01 m; negative is drawdown, positive is head rise. Orange shading is exceedance of trigger (5m drawdown). Doc Ref: Q RP-1399 Revision: 1 Page 105

106 Table 17: Predicted Cumulative Impact Assessment - Springs Scenario A Scenario B Scenario C Scenario D Simulation Details Project Only (NWDA + NEDA) Project + Spring Gully Injection (Project only) Project + Spring Gully Injection (Project + SGRA capped to 5 ML/d) + existing NEDA + SWDA Project + Spring Gully Injection (Project + SGRA capped to 5 ML/d) + Reedy Creek Injection + existing NEDA + SWDA NWDA & NEDA Yes Yes Yes Yes Spring Gully Injection Yes Yes Yes Existing NEDA, SWDA plus injection of SGRA water to max. 5ML/d Yes Yes Reedy Creek Injection Yes Receptor UWIR (2016) Max DDN (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Specific Model Predicted Peak Head Change (m) Predicted Maximum Cumulative Head Change (m) Project Percentage Contribution to Cumulative Drawdown / Headrise Precipice Sandstone Springs Yebna 2 (591) -1 to % Springrock Ck -5 to N/A Spring % W to % Hutton Sandstone Springs Ponies n/a 0.00 n/a 0.01 n/a 0.09 n/a 0.32 n/a Nil Scotts Creek -0.5 to N/A Abyss < < % Doc Ref: Q RP-1399 Revision: 1 Page 106

107 Scenario A Scenario B Scenario C Scenario D Simulation Details Project Only (NWDA + NEDA) Project + Spring Gully Injection (Project only) Project + Spring Gully Injection (Project + SGRA capped to 5 ML/d) + existing NEDA + SWDA Project + Spring Gully Injection (Project + SGRA capped to 5 ML/d) + Reedy Creek Injection + existing NEDA + SWDA W to N/A W59 < < % W80 n/a 0.00 n/a 0.01 n/a 0.08 n/a 0.32 n/a Nil W81 < < % W82 < < % Boxvale Sandstone member Lucky Last < < % Note: Cumulative impacts simulation may overestimate the predicted head rise at the groundwater receptors due to: (1) the incorporation of the UWIR maximum drawdown as part of the cumulative head change calculation, which is not linked to a timing for when the maximum drawdown is predicted to occur, therefore, the drawdown may not correlate with the timing of the maximum head changes from the Project specific modelling; and, (2) the transmissivity applied to the Precipice Sandstone is applied as a constant value across the entire model extent, however, higher transmissivity values are observed to the north of the Project area, which would result in a lower predicted head rise at the groundwater receptors. Predictions are rounded to the nearest 0.01 m; negative is drawdown, positive is head rise. Orange shading is exceedance of trigger (0.20 m drawdown). Cumulative impacts are estimated based on the maximum range data provided by OGIA. n/a denote springs without a predicted drawdown from the UWIR model, and a low to very low spring risk criterion. Doc Ref: Q RP-1399 Revision: 1 Page 107

108 6.11. Management Measures Groundwater and potential impacts to third party users and springs will be managed under the Groundwater Monitoring Plan (Q-LNG-0110-MP-0005) (Appendix 16) and the Spring Gully Aquifer Injection Plan (CDN/ID ) (Appendix 11). The Groundwater Monitoring Plan has been recently updated (Groundwater Management Plan CDN/ID ) for the Australia Pacific LNG Project and submitted to DoEE for approval. Once approved, it will be implemented for the Australia Pacific LNG project and this Project, superseding the current Groundwater Monitoring Plan. Early detection of any potential impacts resulting from CSG extraction will be monitored through the implementation of a groundwater monitoring network as described in the Groundwater Monitoring Plan. The Australia Pacific LNG monitoring network incorporates nearly 200 bores. In addition to this network, data is available from other CSG operators via the Queensland Groundwater Database and the CSG Online program. CSG Online provides public access to near-real time data to over twenty thousand bores across the Surat Basin via the internet. It includes a nest of monitoring bores (Precipice Sandstone, Boxvale Sandstone Member, Hutton Sandstone) installed by OGIA in the vicinity of the Lucky Last, Abyss and Springrock Creek springs as part of the OGIA spring conceptualisation studies (RN , RN , RN , RN123470). The monitoring program is intended to provide an early warning of potential impacts to receptors (both bores and EPBC groundwater communities) to allow sufficient time to undertake further assessment and implement management and mitigation options prior to the occurrence of any significant impacts (as shown in Figure 21). Doc Ref: Q RP-1399 Revision: 1 Page 108

109 Figure 21: Groundwater Exceedance Response Process A Joint Industry Plan has been developed by the CSG operators in the southern Bowen and Surat Basins for a groundwater monitoring and management system to ensure EPBC groundwater communities protected by the EPBC Act are not impacted by CSG production. The principles of the plan are: To ensure a consistent approach to springs monitoring and management between the CSG operators. To monitor groundwater so that meaningful responses can be implemented before there is any impact on EPBC groundwater communities. To use modelling and monitoring to provide an early warning of drawdown approaching EPBC groundwater communities limits to manage increasing levels of risk to MNES. To use of the Surat CMA UWIR model to assess potential pressure changes at the EPBC groundwater communities. Doc Ref: Q RP-1399 Revision: 1 Page 109